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Sample records for public key cryptographic

  1. Quantum walks public key cryptographic system

    OpenAIRE

    Vlachou, C; Rodrigues, J.; Mateus, P.; Paunković, N.; Souto, A.

    2016-01-01

    Quantum Cryptography is a rapidly developing field of research that benefits from the properties of Quantum Mechanics in performing cryptographic tasks. Quantum walks are a powerful model for quantum computation and very promising for quantum information processing. In this paper, we present a quantum public-key cryptographic system based on quantum walks. In particular, in the proposed protocol the public key is given by a quantum state generated by performing a quantum walk. We show that th...

  2. Quantum walk public-key cryptographic system

    Science.gov (United States)

    Vlachou, C.; Rodrigues, J.; Mateus, P.; Paunković, N.; Souto, A.

    2015-12-01

    Quantum Cryptography is a rapidly developing field of research that benefits from the properties of Quantum Mechanics in performing cryptographic tasks. Quantum walks are a powerful model for quantum computation and very promising for quantum information processing. In this paper, we present a quantum public-key cryptographic system based on quantum walks. In particular, in the proposed protocol the public-key is given by a quantum state generated by performing a quantum walk. We show that the protocol is secure and analyze the complexity of public key generation and encryption/decryption procedures.

  3. Cryptographic Key Management System

    Energy Technology Data Exchange (ETDEWEB)

    No, author

    2014-02-21

    This report summarizes the outcome of U.S. Department of Energy (DOE) contract DE-OE0000543, requesting the design of a Cryptographic Key Management System (CKMS) for the secure management of cryptographic keys for the energy sector infrastructure. Prime contractor Sypris Electronics, in collaboration with Oak Ridge National Laboratories (ORNL), Electric Power Research Institute (EPRI), Valicore Technologies, and Purdue University's Center for Education and Research in Information Assurance and Security (CERIAS) and Smart Meter Integration Laboratory (SMIL), has designed, developed and evaluated the CKMS solution. We provide an overview of the project in Section 3, review the core contributions of all contractors in Section 4, and discuss bene ts to the DOE in Section 5. In Section 6 we describe the technical construction of the CKMS solution, and review its key contributions in Section 6.9. Section 7 describes the evaluation and demonstration of the CKMS solution in different environments. We summarize the key project objectives in Section 8, list publications resulting from the project in Section 9, and conclude with a discussion on commercialization in Section 10 and future work in Section 11.

  4. Novel Authentication of Monitoring Data Through the use of Secret and Public Cryptographic Keys

    Energy Technology Data Exchange (ETDEWEB)

    Benz, Jacob M.; Tolk, Keith; Tanner, Jennifer E.

    2014-07-21

    The Office of Nuclear Verification (ONV) is supporting the development of a piece of equipment to provide data authentication and protection for a suite of monitoring sensors as part of a larger effort to create an arms control technology toolkit. This device, currently called the Red Box, leverages the strengths of both secret and public cryptographic keys to authenticate, digitally sign, and pass along monitoring data to allow for host review, and redaction if necessary, without the loss of confidence in the authenticity of the data by the monitoring party. The design of the Red Box will allow for the addition and removal of monitoring equipment and can also verify that the data was collected by authentic monitoring equipment prior to signing the data and sending it to the host and for review. The host will then forward the data to the monitor for review and inspection. This paper will highlight the progress to date of the Red Box development, and will explain the novel method of leveraging both symmetric and asymmetric (secret and public key) cryptography to authenticate data within a warhead monitoring regime.

  5. Cryptographic Key Management and Critical Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Abercrombie, Robert K [ORNL

    2014-05-01

    The Department of Energy Office of Electricity Delivery and Energy Reliability (DOE-OE) CyberSecurity for Energy Delivery Systems (CSEDS) industry led program (DE-FOA-0000359) entitled "Innovation for Increasing CyberSecurity for Energy Delivery Systems (12CSEDS)," awarded a contract to Sypris Electronics LLC to develop a Cryptographic Key Management System for the smart grid (Scalable Key Management Solutions for Critical Infrastructure Protection). Oak Ridge National Laboratory (ORNL) and Sypris Electronics, LLC as a result of that award entered into a CRADA (NFE-11-03562) between ORNL and Sypris Electronics, LLC. ORNL provided its Cyber Security Econometrics System (CSES) as a tool to be modified and used as a metric to address risks and vulnerabilities in the management of cryptographic keys within the Advanced Metering Infrastructure (AMI) domain of the electric sector. ORNL concentrated our analysis on the AMI domain of which the National Electric Sector Cyber security Organization Resource (NESCOR) Working Group 1 (WG1) has documented 29 failure scenarios. The computational infrastructure of this metric involves system stakeholders, security requirements, system components and security threats. To compute this metric, we estimated the stakes that each stakeholder associates with each security requirement, as well as stochastic matrices that represent the probability of a threat to cause a component failure and the probability of a component failure to cause a security requirement violation. We applied this model to estimate the security of the AMI, by leveraging the recently established National Institute of Standards and Technology Interagency Report (NISTIR) 7628 guidelines for smart grid security and the International Electrotechnical Commission (IEC) 63351, Part 9 to identify the life cycle for cryptographic key management, resulting in a vector that assigned to each stakeholder an estimate of their average loss in terms of dollars per day of system

  6. SIMPL Systems, or: Can We Design Cryptographic Hardware without Secret Key Information?

    Science.gov (United States)

    Rührmair, Ulrich

    This paper discusses a new cryptographic primitive termed SIMPL system. Roughly speaking, a SIMPL system is a special type of Physical Unclonable Function (PUF) which possesses a binary description that allows its (slow) public simulation and prediction. Besides this public key like functionality, SIMPL systems have another advantage: No secret information is, or needs to be, contained in SIMPL systems in order to enable cryptographic protocols - neither in the form of a standard binary key, nor as secret information hidden in random, analog features, as it is the case for PUFs. The cryptographic security of SIMPLs instead rests on (i) a physical assumption on their unclonability, and (ii) a computational assumption regarding the complexity of simulating their output. This novel property makes SIMPL systems potentially immune against many known hardware and software attacks, including malware, side channel, invasive, or modeling attacks.

  7. Cryptographer

    Science.gov (United States)

    Sullivan, Megan

    2005-01-01

    For the general public, the field of cryptography has recently become famous as the method used to uncover secrets in Dan Brown's fictional bestseller, The Da Vinci Code. But the science of cryptography has been popular for centuries--secret hieroglyphics discovered in Egypt suggest that code-making dates back almost 4,000 years. In today's…

  8. Secured Cryptographic Key Generation From Multimodal Biometrics Feature Level Fusion Of Fingerprint And Iris

    CERN Document Server

    Jagadeesan, A

    2010-01-01

    Human users have a tough time remembering long cryptographic keys. Hence, researchers, for so long, have been examining ways to utilize biometric features of the user instead of a memorable password or passphrase, in an effort to generate strong and repeatable cryptographic keys. Our objective is to incorporate the volatility of the users biometric features into the generated key, so as to make the key unguessable to an attacker lacking significant knowledge of the users biometrics. We go one step further trying to incorporate multiple biometric modalities into cryptographic key generation so as to provide better security. In this article, we propose an efficient approach based on multimodal biometrics (Iris and fingerprint) for generation of secure cryptographic key. The proposed approach is composed of three modules namely, 1) Feature extraction, 2) Multimodal biometric template generation and 3) Cryptographic key generation. Initially, the features, minutiae points and texture properties are extracted from...

  9. Secured Cryptographic Key Generation From Multimodal Biometrics: Feature Level Fusion of Fingerprint and Iris

    CERN Document Server

    Jagadeesan, A

    2010-01-01

    Human users have a tough time remembering long cryptographic keys. Hence, researchers, for so long, have been examining ways to utilize biometric features of the user instead of a memorable password or passphrase, in an effort to generate strong and repeatable cryptographic keys. Our objective is to incorporate the volatility of the user's biometric features into the generated key, so as to make the key unguessable to an attacker lacking significant knowledge of the user's biometrics. We go one step further trying to incorporate multiple biometric modalities into cryptographic key generation so as to provide better security. In this article, we propose an efficient approach based on multimodal biometrics (Iris and fingerprint) for generation of secure cryptographic key. The proposed approach is composed of three modules namely, 1) Feature extraction, 2) Multimodal biometric template generation and 3) Cryptographic key generation. Initially, the features, minutiae points and texture properties are extracted fr...

  10. Deciding security properties for cryptographic protocols. Application to key cycles

    CERN Document Server

    Comon-Lundh, Hubert; Zalinescu, Eugen

    2007-01-01

    There has been a growing interest in applying formal methods for validating cryptographic protocols and many results have been obtained. In this paper, we re-investigate and extend the NP-complete decision procedure for a bounded number of sessions of Rusinowitch and Turuani. In this setting, constraint systems are now a standard for modeling security protocols. We provide a generic approach to decide general security properties by showing that any constraint system can be transformed in (possibly several) much simpler constraint systems that are called \\emph{solved forms}. As a consequence, we prove that deciding the existence of key cycles is NP-complete for a bounded number of sessions. Indeed, many recent results are concerned with interpreting proofs of security done in symbolic models in the more detailed models of computational cryptography. In the case of symmetric encryption, these results stringently demand that no key cycle (e.g. $\\{k\\}_k$) can be produced during the execution of protocols. We show...

  11. Public key cryptography from weaker assumptions

    DEFF Research Database (Denmark)

    Zottarel, Angela

    This dissertation is focused on the construction of public key cryptographic primitives and on the relative security analysis in a meaningful theoretic model. This work takes two orthogonal directions. In the first part, we study cryptographic constructions preserving their security properties also...

  12. Mathematical Background of Public Key Cryptography

    DEFF Research Database (Denmark)

    Frey, Gerhard; Lange, Tanja

    2005-01-01

    The two main systems used for public key cryptography are RSA and protocols based on the discrete logarithm problem in some cyclic group. We focus on the latter problem and state cryptographic protocols and mathematical background material.......The two main systems used for public key cryptography are RSA and protocols based on the discrete logarithm problem in some cyclic group. We focus on the latter problem and state cryptographic protocols and mathematical background material....

  13. Quantum Key Distribution Protocol with Private-Public Key

    OpenAIRE

    Serna, Eduin H.

    2009-01-01

    A quantum cryptographic protocol based in public key cryptography combinations and private key cryptography is presented. Unlike the BB84 protocol [1] and its many variants [2,3] two quantum channels are used. The present research does not make reconciliation mechanisms of information to derive the key. A three related system of key distribution are described.

  14. K-Medoids-Based Random Biometric Pattern for Cryptographic Key Generation

    Science.gov (United States)

    Garcia-Baleon, H. A.; Alarcon-Aquino, V.; Starostenko, O.

    In this paper we report an approach for cryptographic key generation based on keystroke dynamics and the k-medoids algorithm. The stages that comprise the approach are training-enrollment and user verification. The proposed approach is able to verify the identity of individuals off-line avoiding the use of a centralized database. The performance of the proposed approach is assessed using 20 samples of keystroke dynamics from 20 different users. Simulation results show a false acceptance rate (FAR) of 5.26% and a false rejection rate (FRR) of 10%. The cryptographic key released by the proposed approach may be used in several encryption algorithms.

  15. Revoke and Let Live: A Secure Key Revocation API for Cryptographic Devices

    OpenAIRE

    Cortier, Véronique; Steel,Graham; Wiedling, Cyrille

    2012-01-01

    While extensive research addresses the problem of establishing session keys through cryptographic protocols, relatively little work has appeared addressing the problem of revocation and update of long term keys. We present an API for symmetric key management on embedded devices that supports revocation and prove security properties design in the symbolic model of cryptography. Our API supports two modes of revocation: a passive mode where keys have an expiration time, and an active mode where...

  16. The generation of shared cryptographic keys through channel impulse response estimation at 60 GHz.

    Energy Technology Data Exchange (ETDEWEB)

    Young, Derek P.; Forman, Michael A.; Dowdle, Donald Ryan

    2010-09-01

    Methods to generate private keys based on wireless channel characteristics have been proposed as an alternative to standard key-management schemes. In this work, we discuss past work in the field and offer a generalized scheme for the generation of private keys using uncorrelated channels in multiple domains. Proposed cognitive enhancements measure channel characteristics, to dynamically change transmission and reception parameters as well as estimate private key randomness and expiration times. Finally, results are presented on the implementation of a system for the generation of private keys for cryptographic communications using channel impulse-response estimation at 60 GHz. The testbed is composed of commercial millimeter-wave VubIQ transceivers, laboratory equipment, and software implemented in MATLAB. Novel cognitive enhancements are demonstrated, using channel estimation to dynamically change system parameters and estimate cryptographic key strength. We show for a complex channel that secret key generation can be accomplished on the order of 100 kb/s.

  17. Quality of Service Enhancement of Wireless Sensor Network Using Symmetric Key Cryptographic Schemes

    Directory of Open Access Journals (Sweden)

    Er. Gurjot Singh

    2014-07-01

    Full Text Available A Wireless Sensor Network is a combination of spatially distributed independent nodes deployed in dense environment, communicating wirelessly over limited bandwidth and frequency. Security and Qos is the major concern in wireless sensor network due to its wireless communication nature and constraints like low computation capability, less memory, bounded energy resources, susceptibility to physical capture or damages and the use of insecure wireless communication channels. These constraints make security along with the QoS, a challenge in wireless sensor network. The cryptographic schemes increases the level of security and make it secure against critical attacks but also has a significant impact on the QoS of wireless sensor network. In this paper, the different cryptographic schemes based on asymmetric key and symmetric key cryptography are evaluated. The symmetric key cryptography schemes require less time for processing, less power and also require less storage space as compared to asymmetric key cryptographic schemes, results in less impact on the QoS of wireless sensor network. In this paper, the QoS of wireless sensor network along with cryptographic schemes will be evaluated on the basis of metrics like throughput, jitter, end-to-end delay, total packet received and energy consumption.

  18. Cryptographic Hash Functions

    DEFF Research Database (Denmark)

    Thomsen, Søren Steffen

    2009-01-01

    Cryptographic hash functions are commonly used in many different areas of cryptography: in digital signatures and in public-key cryptography, for password protection and message authentication, in key derivation functions, in pseudo-random number generators, etc. Recently, cryptographic hash...... well-known designs, and also some design and cryptanalysis in which the author took part. The latter includes a construction method for hash functions and four designs, of which one was submitted to the SHA-3 hash function competition, initiated by the U.S. standardisation body NIST. It also includes...

  19. Public-key cryptography based on bounded quantum reference frames

    OpenAIRE

    Ioannou, Lawrence M.; Mosca, Michele

    2009-01-01

    We demonstrate that the framework of bounded quantum reference frames has application to building quantum-public-key cryptographic protocols and proving their security. Thus, the framework we introduce can be seen as a public-key analogue of the framework of Bartlett et al. (Phys. Rev. A 70, 032307), where a private shared reference frame is shown to have cryptographic application. The protocol we present in this paper is an identification scheme, which, like a digital signature scheme, is a ...

  20. Number Theory and Public-Key Cryptography.

    Science.gov (United States)

    Lefton, Phyllis

    1991-01-01

    Described are activities in the study of techniques used to conceal the meanings of messages and data. Some background information and two BASIC programs that illustrate the algorithms used in a new cryptographic system called "public-key cryptography" are included. (CW)

  1. Secure Cryptographic Key Management System (CKMS) Considerations for Smart Grid Devices

    Energy Technology Data Exchange (ETDEWEB)

    Abercrombie, Robert K [ORNL; Sheldon, Frederick T [ORNL; Aldridge, Hal [ORNL; Duren, Mike [Sypris Electronics, LLC; Ricci, Tracy [Sypris Electronics, LLC; Bertino, Elisa [ORNL; Kulatunga, Athula [Purdue University; Navaratne, Uditha Sudheera [Purdue University

    2011-01-01

    In this paper, we examine some unique challenges associated with key management in the Smart Grid and concomitant research initiatives: 1) effectively model security requirements and their implementations, and 2) manage keys and key distribution for very large scale deployments such as Smart Meters over a long period of performance. This will set the stage to: 3) develop innovative, low cost methods to protect keying material, and 4) provide high assurance authentication services. We will present our perspective on key management and will discuss some key issues within the life cycle of a cryptographic key designed to achieve the following: 1) control systems designed, installed, operated, and maintained to survive an intentional cyber assault with no loss of critical function, and 2) widespread implementation of methods for secure communication between remote access devices and control centers that are scalable and cost-effective to deploy.

  2. Apparatus, system and method for providing cryptographic key information with physically unclonable function circuitry

    Energy Technology Data Exchange (ETDEWEB)

    Areno, Matthew

    2015-12-08

    Techniques and mechanisms for providing a value from physically unclonable function (PUF) circuitry for a cryptographic operation of a security module. In an embodiment, a cryptographic engine receives a value from PUF circuitry and based on the value, outputs a result of a cryptographic operation to a bus of the security module. The bus couples the cryptographic engine to control logic or interface logic of the security module. In another embodiment, the value is provided to the cryptographic engine from the PUF circuitry via a signal line which is distinct from the bus, where any exchange of the value by either of the cryptographic engine and the PUF circuitry is for communication of the first value independent of the bus.

  3. 基于公开密钥算法的移动位置隐私保护%Protecting mobile location privacy based on public-key cryptographic algorithm

    Institute of Scientific and Technical Information of China (English)

    陈渝文; 李晓宇

    2016-01-01

    为保证位置信息查询服务的安全性和保密性,提出基于公开密钥算法的移动位置隐私保护方法.引入混淆服务器,用地理位置信息服务器的公有密钥加密用户发出的查询,经过混淆服务器转发给地理位置信息服务器.由于查询经过加密,所以混淆服务器不知道用户查询的内容和当前的位置信息,地理位置信息服务器知道有用户查询,但不知道用户的实体信息.实验结果表明,该方法能够以很小代价更好地保护用户的位置隐私.%To ensure the security and confidentiality of location based services,a mobile location privacy protection method based on public-key cryptography was presented.A confusion server was introduced.Queries issued by the users were encrypted with the public key of location information server,which were forwarded by the confusion server to location information server.The method can protect user's location privacy,because the query is encrypted,the confusion server does not know the contents of the user's query and the current location information.Location information server only knows the query,but does not know user's entity information.The experimental results show that the method can protect the user's location privacy better with marginal cost.

  4. A Cryptographic SoC for Robust Protection of Secret Keys in IPTV DRM Systems

    Science.gov (United States)

    Lee, Sanghan; Yang, Hae-Yong; Yeom, Yongjin; Park, Jongsik

    The security level of an internet protocol television (IPTV) digital right management (DRM) system ultimately relies on protection of secret keys. Well known devices for the key protection include smartcards and battery backup SRAMs (BB-SRAMs); however, these devices could be vulnerable to various physical attacks. In this paper, we propose a secure and cost-effective design of a cryptographic system on chip (SoC) that integrates the BB-SRAM with a cell-based design technique. The proposed SoC provides robust safeguard against the physical attacks, and satisfies high-speed and low-price requirements of IPTV set-top boxes. Our implementation results show that the maximum encryption rate of the SoC is 633Mb/s. In order to verify the data retention capabilities, we made a prototype chip using 0.18µm standard cell technology. The experimental results show that the integrated BB-SRAM can reliably retain data with a 1.4µA leakage current.

  5. Security Notions for Quantum Public-Key Cryptography

    OpenAIRE

    Koshiba, Takeshi

    2007-01-01

    It is well known that Shor's quantum algorithm for integer factorization can break down the RSA public-key cryptosystem, which is widely used in many cryptographic applications. Thus, public-key cryptosystems in the quantum computational setting are longed for cryptology. In order to define the security notions of public-key cryptosystems, we have to model the power of the sender, receiver, adversary and channel. While we may consider a setting where quantum computers are available only to ad...

  6. Protocol based on compressed sensing for high-speed authentication and cryptographic key distribution over a multiparty optical network

    CERN Document Server

    Yu, Wen-Kai; Yao, Xu-Ri; Liu, Xue-Feng; Wu, Ling-An; Zhai, Guang-Jie

    2013-01-01

    We present a protocol for the amplification and distribution of a one-time-pad cryptographic key over a point-to-multipoint optical network based on computational ghost imaging (GI) and compressed sensing (CS). It is shown experimentally that CS imaging can perform faster authentication and increase the key generation rate by an order of magnitude compared with the scheme using computational GI alone. The protocol is applicable for any number of legitimate user, thus, the scheme could be used in real intercity networks where high speed and high security are crucial.

  7. Public Key Cryptography.

    Science.gov (United States)

    Tapson, Frank

    1996-01-01

    Describes public key cryptography, also known as RSA, which is a system using two keys, one used to put a message into cipher and another used to decipher the message. Presents examples using small prime numbers. (MKR)

  8. New Cryptosystem Using Multiple Cryptographic Assumptions

    Directory of Open Access Journals (Sweden)

    E. S. Ismail

    2011-01-01

    Full Text Available Problem statement: A cryptosystem is a way for a sender and a receiver to communicate digitally by which the sender can send receiver any confidential or private message by first encrypting it using the receiver’s public key. Upon receiving the encrypted message, the receiver can confirm the originality of the message’s contents using his own secret key. Up to now, most of the existing cryptosystems were developed based on a single cryptographic assumption like factoring, discrete logarithms, quadratic residue or elliptic curve discrete logarithm. Although these schemes remain secure today, one day in a near future they may be broken if one finds a polynomial algorithm that can efficiently solve the underlying cryptographic assumption. Approach: By this motivation, we designed a new cryptosystem based on two cryptographic assumptions; quadratic residue and discrete logarithms. We integrated these two assumptions in our encrypting and decrypting equations so that the former depends on one public key whereas the latter depends on one corresponding secret key and two secret numbers. Each of public and secret keys in our scheme determines the assumptions we use. Results: The newly developed cryptosystem is shown secure against the three common considering algebraic attacks using a heuristic security technique. The efficiency performance of our scheme requires 2Texp+2Tmul +Thash time complexity for encryption and Texp+2Tmul+Tsrt time complexity for decryption and this magnitude of complexity is considered minimal for multiple cryptographic assumptions-like cryptosystems. Conclusion: The new cryptosystem based on multiple cryptographic assumptions offers a greater security level than that schemes based on a single cryptographic assumption. The adversary has to solve the two assumptions simultaneously to recover the original message from the received corresponding encrypted message but this is very unlikely to happen.

  9. Centralized Cryptographic Key Management and Critical Risk Assessment - CRADA Final Report For CRADA Number NFE-11-03562

    Energy Technology Data Exchange (ETDEWEB)

    Abercrombie, R. K. [ORNL; Peters, Scott [Sypris Electronics, LLC

    2014-05-28

    The Department of Energy Office of Electricity Delivery and Energy Reliability (DOE-OE) Cyber Security for Energy Delivery Systems (CSEDS) industry led program (DE-FOA-0000359) entitled "Innovation for Increasing Cyber Security for Energy Delivery Systems (12CSEDS)," awarded a contract to Sypris Electronics LLC to develop a Cryptographic Key Management System for the smart grid (Scalable Key Management Solutions for Critical Infrastructure Protection). Oak Ridge National Laboratory (ORNL) and Sypris Electronics, LLC as a result of that award entered into a CRADA (NFE-11-03562) between ORNL and Sypris Electronics, LLC. ORNL provided its Cyber Security Econometrics System (CSES) as a tool to be modified and used as a metric to address risks and vulnerabilities in the management of cryptographic keys within the Advanced Metering Infrastructure (AMI) domain of the electric sector. ORNL concentrated our analysis on the AMI domain of which the National Electric Sector Cyber security Organization Resource (NESCOR) Working Group 1 (WG1) has documented 29 failure scenarios. The computational infrastructure of this metric involves system stakeholders, security requirements, system components and security threats. To compute this metric, we estimated the stakes that each stakeholder associates with each security requirement, as well as stochastic matrices that represent the probability of a threat to cause a component failure and the probability of a component failure to cause a security requirement violation. We applied this model to estimate the security of the AMI, by leveraging the recently established National Institute of Standards and Technology Interagency Report (NISTIR) 7628 guidelines for smart grid security and the International Electrotechnical Commission (IEC) 63351, Part 9 to identify the life cycle for cryptographic key management, resulting in a vector that assigned to each stakeholder an estimate of their average loss in terms of dollars per day of system

  10. Algorithms for improved performance in cryptographic protocols.

    Energy Technology Data Exchange (ETDEWEB)

    Schroeppel, Richard Crabtree; Beaver, Cheryl Lynn

    2003-11-01

    Public key cryptographic algorithms provide data authentication and non-repudiation for electronic transmissions. The mathematical nature of the algorithms, however, means they require a significant amount of computation, and encrypted messages and digital signatures possess high bandwidth. Accordingly, there are many environments (e.g. wireless, ad-hoc, remote sensing networks) where public-key requirements are prohibitive and cannot be used. The use of elliptic curves in public-key computations has provided a means by which computations and bandwidth can be somewhat reduced. We report here on the research conducted in an LDRD aimed to find even more efficient algorithms and to make public-key cryptography available to a wider range of computing environments. We improved upon several algorithms, including one for which a patent has been applied. Further we discovered some new problems and relations on which future cryptographic algorithms may be based.

  11. Cryptographic Applications using FPGA Technology

    Directory of Open Access Journals (Sweden)

    Alexandru Coman

    2011-03-01

    Full Text Available Cryptographic systems have become a part of our daily life through the need of security of many common activities such as communication, payments, data transfers etc. The best support in design and implementation of cryptographic applications is offered by embedded systems such as ASICs and FPGAs. In the past few years, the increase in performance of FPGAs has made them key components in implementing cryptographic systems. One of the most important parts of the cryptographic systems is the random number generator used. Combinations of PRNG and TRNG are commonly used. A good and efficient TRNG implementation is very important and can be achieved through FPGA technology.

  12. Low-Power Public Key Cryptography

    Energy Technology Data Exchange (ETDEWEB)

    BEAVER,CHERYL L.; DRAELOS,TIMOTHY J.; HAMILTON,VICTORIA A.; SCHROEPPEL,RICHARD C.; GONZALES,RITA A.; MILLER,RUSSELL D.; THOMAS,EDWARD V.

    2000-11-01

    This report presents research on public key, digital signature algorithms for cryptographic authentication in low-powered, low-computation environments. We assessed algorithms for suitability based on their signature size, and computation and storage requirements. We evaluated a variety of general purpose and special purpose computing platforms to address issues such as memory, voltage requirements, and special functionality for low-powered applications. In addition, we examined custom design platforms. We found that a custom design offers the most flexibility and can be optimized for specific algorithms. Furthermore, the entire platform can exist on a single Application Specific Integrated Circuit (ASIC) or can be integrated with commercially available components to produce the desired computing platform.

  13. Security Requirements for Cryptographic Modules

    Science.gov (United States)

    1999-01-01

    module interfaces; roles, services, and authentication; finite state machine model ; physical security; operating system security; cryptographic key...15 4.4 Finite State Machine Model .......................................................................................................... 17...These areas include cryptographic module specification; module interfaces; roles, services, and authentication; finite state machine model ; physical

  14. Security Notions for Quantum Public-Key Cryptography

    CERN Document Server

    Koshiba, T

    2007-01-01

    It is well known that Shor's quantum algorithm for integer factorization can break down the RSA public-key cryptosystem, which is widely used in many cryptographic applications. Thus, public-key cryptosystems in the quantum computational setting are longed for cryptology. In order to define the security notions of public-key cryptosystems, we have to model the power of the sender, receiver, adversary and channel. While we may consider a setting where quantum computers are available only to adversaries, we generally discuss what are the right security notions for (quantum) public-key cryptosystems in the quantum computational setting. Moreover, we consider the security of quantum public-key cryptosystems known so far.

  15. Cryptographic Boolean functions and applications

    CERN Document Server

    Cusick, Thomas W

    2009-01-01

    Boolean functions are the building blocks of symmetric cryptographic systems. Symmetrical cryptographic algorithms are fundamental tools in the design of all types of digital security systems (i.e. communications, financial and e-commerce).Cryptographic Boolean Functions and Applications is a concise reference that shows how Boolean functions are used in cryptography. Currently, practitioners who need to apply Boolean functions in the design of cryptographic algorithms and protocols need to patch together needed information from a variety of resources (books, journal articles and other sources). This book compiles the key essential information in one easy to use, step-by-step reference. Beginning with the basics of the necessary theory the book goes on to examine more technical topics, some of which are at the frontier of current research.-Serves as a complete resource for the successful design or implementation of cryptographic algorithms or protocols using Boolean functions -Provides engineers and scient...

  16. New Public Key Cryptosystems from Combinatorial Group Theory

    Institute of Scientific and Technical Information of China (English)

    TANG Xueming; WANG Xiaofei; HONG Fan; CUI Guohua

    2006-01-01

    External direct product of some low layer groups such as braid groups and general Artin groups, with a kind of special group action on it, provides a secure cryptographic computation platform, which can keep secure in the quantum computing epoch. Three hard problems on this new platform, Subgroup Root Problem, Multi-variant Subgroup Root Problem and Subgroup Action Problem are presented and well analyzed, which all have no relations with conjugacy. New secure public key encryption system and key agreement protocol are designed based on these hard problems. The new cryptosystems can be implemented in a general group environment other than in braid or Artin groups.

  17. Applications of single-qubit rotations in quantum public-key cryptography

    OpenAIRE

    Nikolopoulos, Georgios M.

    2008-01-01

    We discuss cryptographic applications of single-qubit rotations from the perspective of trapdoor one-way functions and public-key encryption. In particular, we present an asymmetric cryptosystem whose security relies on fundamental principles of quantum physics. A quantum public key is used for the encryption of messages while decryption is possible by means of a classical private key only. The trapdoor one-way function underlying the proposed cryptosystem maps integer numbers to quantum stat...

  18. CRYPTOGRAPHIC STEGANOGRAPHY

    Directory of Open Access Journals (Sweden)

    Vikas Yadav

    2014-08-01

    Full Text Available In the cryptographic steganography system, the message will first be converted into unreadable cipher and then this cipher will be embedded into an image file. Hence this type of system will provide more security by achieving both data encoding as well as data hiding. In this paper we propose an advanced steganocryptic system that combines the features of cryptography and steganography. In this proposed steganocryptic system we will encrypt the message into cipher1 by using Kunal Secure Astro-Encryption and we again encrypt this cipher to cipher2 by using grid cipher technique. Advantage of Kunal Secure Astro-Encryption is that it generates random useless points in between, thus fixed size messages can be generated providing more security compared to other cryptographic algorithms as the number of characters in original message cannot be found from encrypted message without the knowing the black holes. Now we will embed this cipher2 into image file by using visual steganography .In this proposed steganocryptic system we will use modified bit insertion technique to achieve visual steganography. This proposed system will be more secure than cryptography or steganography techniques[digital steganography] alone and also as compared to steganography and cryptography combined systems.

  19. Cryptographic Cloud Storage

    Science.gov (United States)

    Kamara, Seny; Lauter, Kristin

    We consider the problem of building a secure cloud storage service on top of a public cloud infrastructure where the service provider is not completely trusted by the customer. We describe, at a high level, several architectures that combine recent and non-standard cryptographic primitives in order to achieve our goal. We survey the benefits such an architecture would provide to both customers and service providers and give an overview of recent advances in cryptography motivated specifically by cloud storage.

  20. Multiparty Quantum Cryptographic Protocol

    Institute of Scientific and Technical Information of China (English)

    M. Ramzan; M. K. Khan

    2008-01-01

    We propose a multiparty quantum cryptographic protocol. Unitary operators applied by Bob and Charlie, on their respective qubits of a tripartite entangled state encoding a classical symbol that can be decoded at Alice's end with the help of a decoding matrix. Eve's presence can be detected by the disturbance of the decoding matrix. Our protocol is secure against intercept-resend attacks. Furthermore, it is efficient and deterministic in the sense that two classical bits can be transferred per entangled pair of qubits. It is worth mentioning that in this protocol, the same symbol can be used for key distribution and Eve's detection that enhances the effciency of the protocol.

  1. Cryptographic Research and NSA: Report of the Public Cryptography Study Group.

    Science.gov (United States)

    Davida, George I.

    1981-01-01

    The Public Cryptography Study Group accepted the claim made by the National Security Agency that some information in some publications concerning cryptology could be inimical to national security, and is allowing the establishment of a voluntary mechanism, on an experimental basis, for NSA to review cryptology manuscripts. (MLW)

  2. Efficient Certificate-Based Signcryption Secure against Public Key Replacement Attacks and Insider Attacks

    OpenAIRE

    Yang Lu; Jiguo Li

    2014-01-01

    Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certific...

  3. Applications of single-qubit rotations in quantum public-key cryptography

    Science.gov (United States)

    Nikolopoulos, Georgios M.

    2008-03-01

    We discuss cryptographic applications of single-qubit rotations from the perspective of trapdoor one-way functions and public-key encryption. In particular, we present an asymmetric cryptosystem whose security relies on fundamental principles of quantum physics. A quantum public key is used for the encryption of messages while decryption is possible by means of a classical private key only. The trapdoor one-way function underlying the proposed cryptosystem maps integer numbers to quantum states of a qubit and its inversion can be infeasible by virtue of the Holevo’s theorem.

  4. Hybrid Cryptographic Processor for Secure Communication Using FPGA

    OpenAIRE

    Savitha Raj.S; Merlin Sharmila.A; Poorinima Beneta.P

    2013-01-01

    Cryptographic hash functions are mainly used for the purpose of authentication and for integrity of messages. In this paper, we investigate high-speed, efficient hardware algorithm which is a combination of both RSA and BLAKE for providing privacy and security in data networks including encryption/decryption. Hash function- BLAKE is a new standard candidate algorithm; it is one of the finalists in the SHA-3 competition by NIST. RSA is the asymmetric public key cryptography system. Since this ...

  5. Critical analysis of the Bennett-Riedel attack on secure cryptographic key distributions via the Kirchhoff-Law-Johnson-noise scheme.

    Directory of Open Access Journals (Sweden)

    Laszlo B Kish

    Full Text Available Recently, Bennett and Riedel (BR (http://arxiv.org/abs/1303.7435v1 argued that thermodynamics is not essential in the Kirchhoff-law-Johnson-noise (KLJN classical physical cryptographic exchange method in an effort to disprove the security of the KLJN scheme. They attempted to demonstrate this by introducing a dissipation-free deterministic key exchange method with two batteries and two switches. In the present paper, we first show that BR's scheme is unphysical and that some elements of its assumptions violate basic protocols of secure communication. All our analyses are based on a technically unlimited Eve with infinitely accurate and fast measurements limited only by the laws of physics and statistics. For non-ideal situations and at active (invasive attacks, the uncertainly principle between measurement duration and statistical errors makes it impossible for Eve to extract the key regardless of the accuracy or speed of her measurements. To show that thermodynamics and noise are essential for the security, we crack the BR system with 100% success via passive attacks, in ten different ways, and demonstrate that the same cracking methods do not function for the KLJN scheme that employs Johnson noise to provide security underpinned by the Second Law of Thermodynamics. We also present a critical analysis of some other claims by BR; for example, we prove that their equations for describing zero security do not apply to the KLJN scheme. Finally we give mathematical security proofs for each BR-attack against the KLJN scheme and conclude that the information theoretic (unconditional security of the KLJN method has not been successfully challenged.

  6. Critical analysis of the Bennett-Riedel attack on secure cryptographic key distributions via the Kirchhoff-Law-Johnson-noise scheme.

    Science.gov (United States)

    Kish, Laszlo B; Abbott, Derek; Granqvist, Claes G

    2013-01-01

    Recently, Bennett and Riedel (BR) (http://arxiv.org/abs/1303.7435v1) argued that thermodynamics is not essential in the Kirchhoff-law-Johnson-noise (KLJN) classical physical cryptographic exchange method in an effort to disprove the security of the KLJN scheme. They attempted to demonstrate this by introducing a dissipation-free deterministic key exchange method with two batteries and two switches. In the present paper, we first show that BR's scheme is unphysical and that some elements of its assumptions violate basic protocols of secure communication. All our analyses are based on a technically unlimited Eve with infinitely accurate and fast measurements limited only by the laws of physics and statistics. For non-ideal situations and at active (invasive) attacks, the uncertainly principle between measurement duration and statistical errors makes it impossible for Eve to extract the key regardless of the accuracy or speed of her measurements. To show that thermodynamics and noise are essential for the security, we crack the BR system with 100% success via passive attacks, in ten different ways, and demonstrate that the same cracking methods do not function for the KLJN scheme that employs Johnson noise to provide security underpinned by the Second Law of Thermodynamics. We also present a critical analysis of some other claims by BR; for example, we prove that their equations for describing zero security do not apply to the KLJN scheme. Finally we give mathematical security proofs for each BR-attack against the KLJN scheme and conclude that the information theoretic (unconditional) security of the KLJN method has not been successfully challenged.

  7. Quantum Public-Key Cryptosystem

    Science.gov (United States)

    Luo, Ming-Xing; Chen, Xiu-Bo; Yun, Deng; Yang, Yi-Xian

    2012-03-01

    Quantum one-way functions play a fundamental role in cryptography because of its necessity for the secure encryption schemes taking into account the quantum computer. In this paper our purpose is to establish a theoretical framework for a candidate of the quantum one-way functions and quantum trapdoor functions based on one-parameter unitary groups. The dynamics of parameterized unitary groups ensure the one-wayness and quantum undistinguishability in different levels, and the physical feasibility are derived from the simultaneous approximation of its infinitesimal generators. Moreover, these special functions are used to construct new cryptosystems-the quantum public-key cryptosystems for encrypting both the classical and quantum information.

  8. Applied public-key steganography

    Science.gov (United States)

    Guillon, Pierre; Furon, Teddy; Duhamel, Pierre

    2002-04-01

    We consider the problem of hiding information in a steganographic framework, i.e. embedding a binary message within an apparently innocuous content, in order to establish a suspicion-free digital communication channel. The adversary is passive as no intentional attack is foreseen. The only threat is that she discovers the presence of a hidden communication. The main goal of this article is to find if the Scalar Costa Scheme, a recently published embedding method exploiting side information at the encoder, is suitable for that framework. We justify its use assessing its security level with respect to the Cachin's criterion. We derive a public-key stego-system following the ideas of R. Anderson and P. Petitcolas. This technique is eventually applied to PCM audio contents. Experimental performances are detailed in terms of bit-rate and Kullback-Leibler distance.

  9. Improved RSA cryptosystem based on the study of number theory and public key cryptosystems

    Directory of Open Access Journals (Sweden)

    Israt Jahan

    2015-01-01

    Full Text Available Security is required to transmit confidential information over the network. Security is also demanding in wide range of applications. Cryptographic algorithms play a vital role in providing the data security against malicious attacks. RSA algorithm is extensively used in the popular implementations of Public Key Infrastructures. In asymmetric key cryptography, also called Public Key cryptography, two different keys (which form a key pair are used. One key is used for encryption and only the other corresponding key must be used for decryption. No other key can decrypt the message – not even the original (i.e. the first key used for encryption. In this paper, we have proposed an improved approach of RSA algorithm using two public key pairs and using some mathematical logic rather than sending one public key d irectly.Because if an attacker has an opportunity of getting the public key componet they can find private key value by brute force search. General Terms: Cryptography, network security

  10. A Partially Non-Cryptographic Security Routing Protocol in Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    CHEN Jing; CUI Guohua

    2006-01-01

    In this paper, we propose a partially non-cryptographic security routing protocol(PNCSR ) that protects both routing and data forwarding operations through the same reactive approach. PNCSR only apply public-key cryptographic system in managing token, but it doesn't utilize any cryptographic primitives on the routing messages. In PNCSR, each node is fair. Local neighboring nodes collaboratively monitor each other and sustain each other. It also uses a novel credit strategy which additively increases the token lifetime each time a node renews its token. We also analyze the storage, computation, and communication overhead of PNCSR, and provide a simple yet meaningful overhead comparison. Finally, the simulation results show the effectiveness of PNCSR in various situations.

  11. A threshold key escrow scheme based on public key cryptosystem

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In key escrow field it is important to solve the problem thatuser's secret key completely depends on the trusted escrow agency. In 1995, some methods of solving the problem were presented. But these methods are no better than that of directly using threshold cryptography. In this paper, we present a common pattern of threshold key escrow scheme based on public key cryptosystem, and a detailed design based on the improved RSA algorithm is given. The above problem is solved by this scheme.

  12. Public-Key Encryption with Delegated Search

    NARCIS (Netherlands)

    Ibraimi, Luan; Nikova, Svetla; Hartel, Pieter; Jonker, Willem

    2011-01-01

    In public-key setting, Alice encrypts email with public key of Bob, so that only Bob will be able to learn contents of email. Consider scenario when computer of Alice is infected and unbeknown to Alice it also embeds malware into message. Bob's company, Carol, cannot scan his email for mali

  13. Efficient certificate-based signcryption secure against public key replacement attacks and insider attacks.

    Science.gov (United States)

    Lu, Yang; Li, Jiguo

    2014-01-01

    Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certificate-based signcryption scheme is insecure in our model. We also propose a new certificate-based signcryption scheme that achieves security against both public key replacement attacks and insider attacks. We prove in the random oracle model that the proposed scheme is chosen-ciphertext secure and existentially unforgeable. Performance analysis shows that the proposed scheme outperforms all the previous certificate-based signcryption schemes in the literature.

  14. Efficient Certificate-Based Signcryption Secure against Public Key Replacement Attacks and Insider Attacks

    Directory of Open Access Journals (Sweden)

    Yang Lu

    2014-01-01

    Full Text Available Signcryption is a useful cryptographic primitive that achieves confidentiality and authentication in an efficient manner. As an extension of signcryption in certificate-based cryptography, certificate-based signcryption preserves the merits of certificate-based cryptography and signcryption simultaneously. In this paper, we present an improved security model of certificate-based signcryption that covers both public key replacement attack and insider security. We show that an existing certificate-based signcryption scheme is insecure in our model. We also propose a new certificate-based signcryption scheme that achieves security against both public key replacement attacks and insider attacks. We prove in the random oracle model that the proposed scheme is chosen-ciphertext secure and existentially unforgeable. Performance analysis shows that the proposed scheme outperforms all the previous certificate-based signcryption schemes in the literature.

  15. An Internet Key Exchange Protocol Based on Public Key Infrastructure

    Institute of Scientific and Technical Information of China (English)

    朱建明; 马建峰

    2004-01-01

    Internet key exchange (IKE) is an automated key exchange mechanism that is used to facilitate the transfer of IPSec security associations (SAs). Public key infrastructure (PKI) is considered as a key element for providing security to new distributed communication networks and services. In this paper, we concentrate on the properties of the protocol of Phase 1 IKE. After investigating IKE protocol and PKI technology, we combine IKE protocol and PKI and present an implementation scheme of the IKE based on PKI. Then, we give a logic analysis of the proposed protocol with the BAN-logic and discuss the security of the protocol. The result indicates that the protocol is correct and satisfies the security requirements of Internet key exchange.

  16. Security analysis of public key watermarking schemes

    Science.gov (United States)

    Craver, Scott A.; Katzenbeisser, Stefan

    2001-12-01

    Traditional watermarking systems require the complete disclosure of the watermarking key in the watermark verification process. In most systems an attacker is able to remove the watermark completely once the key is known, thus subverting the intention of copyright protection. To cope with this problem, public-key watermarking schemes were proposed that allow asymmetric watermark detection. Whereas a public key is used to insert watermarks in digital objects, the marks can be verified with a private key. Knowledge of this private key does not allow piracy. We describe two public-key watermarking schemes which are similar in spirit to zero-knowledge proofs. The key idea of one system is to verify a watermark in a blinded version of the document, where the scrambling is determined by the private key. A probabilistic protocol is constructed that allows public watermark detection with probability of 1/2; by iteration, the verifier can get any degree of certainty that the watermark is present. The second system is based on watermark attacks, using controlled counterfeiting to conceal real watermark data safely amid data useless to an attacker.

  17. Reducing Communication Overhead For Authentication Using Self Contained Public Key Management Scheme In MANET

    Directory of Open Access Journals (Sweden)

    Gundala Swathi

    2013-06-01

    Full Text Available In the past few years, we have seen a rapid increase in important application fields of Mobile ad-hoc networks (MANET. Hence, many industrial and academic researchers have been conducted. Because, these applications are closely related to human beings and their physical environment, the usage of MANET on a large scale depends on whether we can provide proper dependability. Particularly, security is the most important issue in MANET because of the limitation in resources. Management of keys is the most necessary activity for providing security for the network. MANETs have resource limitations. Thus using public-key based solutions is not feasible. Thus, we use symmetric key establishment. In this paper, a key management scheme which is self contained and public is represented.This scheme achieves near zero communication overhead while providing security services. Cryptographic keys in small numbers are inputted at all nodes prior to the deployment in network. Mathematical Combinations of pairs of keys, both public and private is used for better utilization of storage space. This means a combination of more than one key pair is utilized by nodes for the encryption and the decryption of messages. A secure communication algorithm for forwarding the packets in MANET is also proposed.

  18. New Eavesdropper Detection Method in Quantum Cryptograph

    Directory of Open Access Journals (Sweden)

    Cătălin Anghel

    2011-12-01

    Full Text Available ecurity of quantum cryptographic algorithms is one of the main research directions in quantum cryptography. Security growth of the quantum key distribution systems can be realized by detecting the eavesdropper quickly, precisely and without letting any secret information in the hands of the enemy. This paper proposes a new method, named QBTT, to detect the enemy who try to tap the communication channel. The QBTT method can be implemented in every type of quantum key distribution scheme.

  19. A String-Based Public Key Cryptosystem

    CERN Document Server

    Andrecut, M

    2014-01-01

    Traditional public key cryptography is based on number theory, and suffers from problems such as dealing with very large numbers and large prime numbers, making key creation cumbersome. Here, we propose a new public key cryptosystem based on strings only, which avoids the difficulties of the traditional number theory approach. The security mechanism for generating public and secret keys is ensured by a recursive encoding mechanism embedded in a quasi-commutative-random function, resulted from the composition of a quasi-commutative function with a pseudo-random function. Due to the inherent construction algorithm of the the proposed cryptosystem, the resulted mathematical inversion problem is likely to be harder than the classical discrete logarithm or integer factorization problems. Furthermore, the proposed cryptosystem is immune against the known quantum algorithm attacks.

  20. CRYPTOGRAPHIC PROTOCOL DEPENDING ON BIOMETRIC AUTHENTICATION

    Directory of Open Access Journals (Sweden)

    SANJUKTA PAL

    2013-02-01

    Full Text Available In modern age, security is the most challenging issue for using the secure data used by computer. This cryptographic protocol on biometric authentication is nothing but the combination of cryptography and biometric authentication. Here the same idea of cryptography is working (i.e. using key, conversion of plain textinto cipher text called encryption and the reverse, means cipher text to plain text called decryption. Here the most promising method fingerprint geometry of biometric authentication is used as the key for encryption and decryption. Here this cryptographic protocol is just an algorithm for matching the key means matching of stored fingerprint images say DB Images with further given fingerprint image say Final Image. For matching purpose we used binary conversion of images. This algorithm is suitable for any type of data (means text data, multimedia data etc.

  1. Quantum attacks on public-key cryptosystems

    CERN Document Server

    Yan, Song Y

    2013-01-01

    The cryptosystems based on the Integer Factorization Problem (IFP), the Discrete Logarithm Problem (DLP) and the Elliptic Curve Discrete Logarithm Problem (ECDLP) are essentially the only three types of practical public-key cryptosystems in use. The security of these cryptosystems relies heavily on these three infeasible problems, as no polynomial-time algorithms exist for them so far. However, polynomial-time quantum algorithms for IFP, DLP and ECDLP do exist, provided that a practical quantum computer exists.Quantum Attacks on Public-Key Cryptosystems presemts almost all?known quantum comput

  2. Applying Evolutionary Algorithm to Public Key Cryptosystems

    Institute of Scientific and Technical Information of China (English)

    Tu Hang; Li Li; Wu Tao-jun; Li Yuan- xiang

    2003-01-01

    A best algorithm generated scheme is proposed in the paper by making use of the thought of evolutionary algorithm, which can generate dynamically the best algorithm of generating primes in RSA cryptography under different conditions. Taking into account the factors of time, space and security integrated, this scheme possessed strong practicability. The paper also proposed a model of multi degree parallel evolutionary algorithrn to evaluate synthetically the efficiency and security of the public key cryptography. The model con tributes to designing public key cryptography system too.

  3. Dynamic Threshold Public-Key Encryption

    OpenAIRE

    Delerablée, Cécile; Pointcheval, David

    2008-01-01

    The original publication is available at www.springerlink.com; International audience; This paper deals with threshold public-key encryption which allows a pool of players to decrypt a ciphertext if a given threshold of authorized players cooperate. We generalize this primitive to the dynamic setting, where any user can dynamically join the system, as a possible recipient; the sender can dynamically choose the authorized set of recipients, for each ciphertext; and the sender can dynamically s...

  4. MOBILE PAYMENTMETHODBASED ON PUBLIC-KEY CRYPTOGRAPHY

    Directory of Open Access Journals (Sweden)

    Adnan A. Hnaif

    2015-03-01

    Full Text Available Mobile payment is defined as mobile money, which is considered as an attractive alternative for cash, cheque, or credit. In this paper we propose a new secure mobile paymentmethod. This method is summarized in three processes: firstly, the authentication process, which involves the authentication phases for the applied customers. Secondly, the member recognition process which tests and ensures the customer membership by the market server. Finally, payment processwhich will be done by ciphering the customer information using public-key encryption cryptosystem (RSA, to be submitted over an insecure network to the market server. Actually, this mobile payment methodis more efficient than otherpayment methods since the customer can pay from his/her own mobilephone without any extra cost and effort. The RSA public-key encryption system ensures the security of the proposed method. However, to prevent a brute force attack, the choice of the key size becomes crucial.

  5. Efficient secure-channel free public key encryption with keyword search for EMRs in cloud storage.

    Science.gov (United States)

    Guo, Lifeng; Yau, Wei-Chuen

    2015-02-01

    Searchable encryption is an important cryptographic primitive that enables privacy-preserving keyword search on encrypted electronic medical records (EMRs) in cloud storage. Efficiency of such searchable encryption in a medical cloud storage system is very crucial as it involves client platforms such as smartphones or tablets that only have constrained computing power and resources. In this paper, we propose an efficient secure-channel free public key encryption with keyword search (SCF-PEKS) scheme that is proven secure in the standard model. We show that our SCF-PEKS scheme is not only secure against chosen keyword and ciphertext attacks (IND-SCF-CKCA), but also secure against keyword guessing attacks (IND-KGA). Furthermore, our proposed scheme is more efficient than other recent SCF-PEKS schemes in the literature.

  6. Information Hiding in CSS : A Secure Scheme Text-Steganography using Public Key Cryptosystem

    CERN Document Server

    Kabetta, Herman; Suyoto,

    2012-01-01

    In many recent years, the programming world has been introduced about a new programming language for designing websites, it is CSS that can be be used together with HTML to develop a web interface. And now, these two programming languages as if inseparably from each other. As a client-side scripting, CSS is visible by all users as the original script, but it can not be granted changed. Website is a tool of information disseminator throughout the world, this is certainly can be used to a secret communication by using CSS as a message hider. This paper proposed a new scheme using web tools like CSS for hiding informations. This is a secret communication mechanism using text steganography techniques that is embedded messages on CSS files and is further encrypted using RSA as a public key cryptographic algorithm.

  7. Symmetric cryptographic protocols for extended millionaires' problem

    Institute of Scientific and Technical Information of China (English)

    LI ShunDong; WANG DaoShun; DAI YiQi

    2009-01-01

    Yao's millionaires' problem is a fundamental problem in secure multiparty computation, and its solutions have become building blocks of many secure multiparty computation solutions. Unfortunately,most protocols for millionaires' problem are constructed based on public cryptography, and thus are inefficient. Furthermore, all protocols are designed to solve the basic millionaires' problem, that is,to privately determine which of two natural numbers is greater. If the numbers are real, existing solutions do not directly work. These features limit the extensive application of the existing protocols. This study introduces and refines the first symmetric cryptographic protocol for the basic millionaires' problem, and then extends the symmetric cryptographic protocol to privately determining which of two real numbers is greater, which are called the extended millionaires' problem, and proposes corresponding Constructed based on symmetric cryptography, these protocols are very efficient.

  8. Cryptographic Protocols Based on Root Extracting

    DEFF Research Database (Denmark)

    Koprowski, Maciej

    In this thesis we design new cryptographic protocols, whose security is based on the hardness of root extracting or more speci cally the RSA problem. First we study the problem of root extraction in nite Abelian groups, where the group order is unknown. This is a natural generalization of the...... complexity of root extraction, even if the algorithm can choose the "public exponent'' itself. In other words, both the standard and the strong RSA assumption are provably true w.r.t. generic algorithms. The results hold for arbitrary groups, so security w.r.t. generic attacks follows for any cryptographic...... construction based on root extracting. As an example of this, we modify Cramer-Shoup signature scheme such that it becomes a genericm algorithm. We discuss then implementing it in RSA groups without the original restriction that the modulus must be a product of safe primes. It can also be implemented in class...

  9. PKDIP: Efficient Public-Key-Based Data Integrity Protection for Wireless Image Sensors

    Directory of Open Access Journals (Sweden)

    Changsheng Wan

    2015-01-01

    Full Text Available Due to limited energy of “wireless image sensors (WISs,” existing data integrity protection mechanisms typically employ a hash-function-based signing algorithm to generate “message authentication codes (MACs” for long image frames. However, hash-function-based signing algorithm requires the WIS and the “end user (EU” sharing a secret, which leads to a new security issue: Once the EU becomes malicious due to some reasons, it will be able to forge the WIS’s data since it holds the shared secret. Therefore, public-key cryptography is desirable. Unfortunately, public-key cryptographic operations are quite time-consuming for energy-restrained WISs. Facing this dilemma, we present a novel data integrity protection protocol named PKDIP in this paper. Similar to the mechanisms of this field, PKDIP generates MACs for data integrity protection. However, different from other well-known approaches, PKDIP introduces the “Montgomery Modular Multiplication (MontMM” technique to current public-key-based signing algorithms. Since MontMM is much more efficient than hash functions, PKDIP can reduce the signing cost significantly. Experimental results show PKDIP can even be more efficient than hash-function-based schemes.

  10. Cryptographic Hash Functions

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Knudsen, Lars Ramkilde

    2010-01-01

    value should not serve as an image for two distinct input messages and it should be difficult to find the input message from a given hash value. Secure hash functions serve data integrity, non-repudiation and authenticity of the source in conjunction with the digital signature schemes. Keyed hash...... important applications has also been analysed. This successful cryptanalysis of the standard hash functions has made National Institute of Standards and Technology (NIST), USA to initiate an international public competition to select the most secure and efficient hash function as the future hash function...... based MACs are reported. The goals of NIST's SHA-3 competition and its current progress are outlined....

  11. Evolution of Electronic Passport Scheme using Cryptographic Protocol along with Biometrics Authentication System

    Directory of Open Access Journals (Sweden)

    V.K. Narendira Kumar

    2012-03-01

    Full Text Available Millions of citizens around the world have already acquired their new electronic passport. The e-passport is equipped with contactless chip which stores personal data of the passport holder, information about the passport and the issuing institution, as well as with a multiple biometrics enabling cryptographic functionality. Countries are required to build a Public Key Infrastructure, biometric and Radio Frequency Identification to support various cryptographic, as this is considered the basic tools to prove the authenticity and integrity of the Machine Readable Travel Documents. The large-scale worldwide PKI is construction, by means of bilateral trust relationships between Countries. Investigate the good practices, which are essential for the establishment of a global identification scheme based on e-passports. The paper explores the privacy and security implications of this impending worldwide experiment in biometrics authentication technology.

  12. Cryptographic Hash functions - a review

    Directory of Open Access Journals (Sweden)

    Rajeev Sobti

    2012-03-01

    Full Text Available Cryptographic Hash functions are used to achieve a number of security objectives. In this paper, we bring out the importance of hash functions, its various structures, design techniques, attacks and the progressive recent development in this field.

  13. Formalizing the Relationship Between Commitment and Basic Cryptographic Primitives

    Directory of Open Access Journals (Sweden)

    S. Sree Vivek

    2016-11-01

    Full Text Available Signcryption is a cryptographic primitive which offers the functionality of both digital signature and encryption with lower combined computational cost. On the other hand, commitment scheme allows an entity to commit to a value, where the entity reveals the committed value later during a decommit phase. In this paper, we explore the connection between commitment schemes, public key encryption, digital signatures and signcryption. We establish formal relationship between commitment and the other primitives. Our main result is that we show signcryption can be used as a commitment scheme with appropriate security notions. We show that if the underlying signcryption scheme is IND-CCA2 secure, then the hiding property of the commitment scheme is satisfied. Similarly, we show that if the underlying signcryption scheme is unforgeable, then the relaxed biding property of the commitment scheme is satisfied. Moreover, we prove that if the underlying signcryption scheme is NM-CCA2, then the commitment scheme is non-malleable.

  14. A New Public-Key Encryption Scheme

    Institute of Scientific and Technical Information of China (English)

    Hai-Bo Tian; Xi Sun; Yu-Min Wang

    2007-01-01

    This paper proposes a new public-key encryption scheme which removes one element from the public-key tuple of the original Cramer-Shoup scheme.As a result, a ciphertext is not a quadruple but a triple at the cost of a strong assumption,the third version of knowledge of exponent assumption (KEA3).Under assumptions of KEA3, a decision Diffie-Hellman (DDH) and a variant of target collision resistance (TCRv), the new scheme is proved secure against indistinguishable adaptive chosen ciphertext attack (IND-CCA2).This scheme is as efficient as Damgard ElGamal (DEG) scheme when it makes use of a well-known algorithm for product of exponentiations.The DEG scheme is recently proved IND-CCA1 secure by Bellare and Palacio in ASIACRYPT 2004 under another strong assumption.In addition to our IND-CCA2 secured scheme, we also believe that the security proof procedure itself provides a well insight for ElGamal-based encryption schemes which are secure in real world.

  15. KeyChains: A Decentralized Public-Key Infrastructure

    Science.gov (United States)

    2006-03-02

    exposed. This problem is easily solved in KeyChains, taking inspiration from existing techniques: certificate expiration, revocation lists and online...the peer. The peer maintains an access control list indicating what operations (key storage, key retrieval, and peer management) are permitted to a...2002, Norfolk, VA, September 2002. [9] http://www.umiacs.umd.edu/˜mmarsh/ CODEX /. [10] A. Datta, M. Hauswirth, and K. Aberer. Beyond ”web of trust

  16. An Inexpensive Device for Teaching Public Key Encryption

    Science.gov (United States)

    Pendegraft, Norman

    2009-01-01

    An inexpensive device to assist in teaching the main ideas of Public Key encryption and its use in class to illustrate the operation of public key encryption is described. It illustrates that there are two keys, and is particularly useful for illustrating that privacy is achieved by using the public key. Initial data from in class use seem to…

  17. Superposition Attacks on Cryptographic Protocols

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Funder, Jakob Løvstad; Nielsen, Jesper Buus

    2011-01-01

    Attacks on classical cryptographic protocols are usually modeled by allowing an adversary to ask queries from an oracle. Security is then defined by requiring that as long as the queries satisfy some constraint, there is some problem the adversary cannot solve, such as compute a certain piece...... of information. In this paper, we introduce a fundamentally new model of quantum attacks on classical cryptographic protocols, where the adversary is allowed to ask several classical queries in quantum superposition. This is a strictly stronger attack than the standard one, and we consider the security...

  18. Unconditionally-secure and reusable public-key authentication

    CERN Document Server

    Ioannou, Lawrence M

    2011-01-01

    We present a quantum-public-key identification protocol and show that it is secure against a computationally-unbounded adversary. This demonstrates for the first time that unconditionally-secure and reusable public-key authentication is possible in principle with (pure-state) public keys.

  19. Wireless Secured Data Transmission using Cryptographic Techniques through FPGA

    Directory of Open Access Journals (Sweden)

    I.Rama Satya Nageswara Rao

    2016-02-01

    Full Text Available The need to protect the data disturbances and unauthorized access in communication has led to development of several cryptographic algorithms. Current issue in modern world as popularity of internet, e-commerce and communication technologies has emerging and they became the medium to security threats. Due to advancement in cryptographic techniques the DNA technique is a new crypto algorithm to encrypt and decrypt data. It consists of two stage encryption based on DNA sequence enhances the data security compared to conventional methods. In encryption process the former stage will encrypt the data (plain text with a random key generated by random DNA sequence generator. Latter and final stage the encrypted data is re-encrypted with DNA translation to generate cipher. The cryptographic techniques (symmetric algorithm is designed and simulated using Xilinx ISE and targeted on Spartan-3E FPGA interfaced with ZigBee for wireless communication.

  20. Pythagorean Triples and Cryptographic Coding

    CERN Document Server

    Kak, Subhash

    2010-01-01

    This paper summarizes basic properties of PPTs and shows that each PPT belongs to one of six different classes. Mapping an ordered sequence of PPTs into a corresponding sequence of these six classes makes it possible to use them in cryptography. We pose problems whose solution would facilitate such cryptographic application.

  1. Cryptographically enforced search pattern hiding

    NARCIS (Netherlands)

    Bösch, Christoph Tobias

    2015-01-01

    Searchable encryption is a cryptographic primitive that allows a client to out- source encrypted data to an untrusted storage provider, while still being able to query the data without decrypting. To allow the server to perform the search on the encrypted data, a so-called trapdoor is generated by t

  2. Probability Distributions over Cryptographic Protocols

    Science.gov (United States)

    2009-06-01

    exception. Cryptyc integrates use of pattern- matching in the spi calculus framework , which in turn allows the specification of nested cryptographic...programs too: the metaheuristic search for security protocols,” Information and Software Technology, vol. 43, pp. 891– 904, December 2001. 131 [9] X

  3. Weak-Keys in Public Key Cryptosystems Based on Discrete Logarithms

    Institute of Scientific and Technical Information of China (English)

    TAI Suiyan; LUO Ping; PENG Xiaoning; WANG Daoshun

    2005-01-01

    The discrete logarithm method is the foundation of many public key algorithms. However, one type of key, defined as a weak-key, reduces the security of public key cryptosystems based on the discrete logarithm method. The weak-key occurs if the public key is a factor or multiple of the primitive element, in which case the user's private key is not needed but can be obtained based on the character of the public key. An algorithm is presented that can easily test whether there is a weak-key in the cryptosystem. An example is given to show that an attack can be completed for the Elgamal digital signature if a weak-key exists, therefore validating the danger of weak-keys. Methods are given to prevent the generation of these weak-keys.

  4. One-way quantum identity authentication based on public key

    Institute of Scientific and Technical Information of China (English)

    ZHANG XingLan

    2009-01-01

    Based on public key, a quantum identity authenticated (QIA) system is proposed without quantum entanglement. The public key acts as the authentication key of a user. Following the idea of the classical public key infrastructure (PKI), a trusted center of authentication (CA) is involved. The user selects a public key randomly and CA generates a private key for the user according to his public key. When it is necessary to perform QIA, the user sends a sequence of single photons encoded with its private key and a message to CA. According to the corresponding secret key kept by CA, CA performs the unitary operations on the single photon sequence. At last, the receiver can judge whether the user is an impersonator.

  5. Cryptographic Hash Functions

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Knudsen, Lars Ramkilde

    2010-01-01

    value should not serve as an image for two distinct input messages and it should be difficult to find the input message from a given hash value. Secure hash functions serve data integrity, non-repudiation and authenticity of the source in conjunction with the digital signature schemes. Keyed hash...

  6. Efficient Authenticated Key Agreement Protocol Using Self-Certified Public Keys from Pairings

    Institute of Scientific and Technical Information of China (English)

    SHAO Zu-hua

    2005-01-01

    An efficient authenticated key agreement protocol is proposed, which makes use of bilinear pairings and selfcertified public keys. Its security is based on the security assumptions of the bilinear Diffie-Hellman problem and the computational Diffie-Hellman problem. Users can choose their private keys independently. The public keys and identities of users can be verified implicitly when the session key being generating in a logically single step. A trusted Key Generation Center is no longer required as in the ID-based authenticated key agreement protocols. Compared with existing authenticated key agreement protocols from pairings, the new proposed protocol is more efficient and secure.

  7. Rationality in the Cryptographic Model

    DEFF Research Database (Denmark)

    Hubacek, Pavel

    This thesis presents results in the field of rational cryptography. In the first part we study the use of cryptographic protocols to avoid mediation and binding commitment when implementing game theoretic equilibrium concepts. First, we concentrate on the limits of cryptographic cheap talk....... The second part presents a study of the problem of verifiable delegation of computation in the rational setting. We define rational arguments, an extension of the recent concept of rational proofs into the computational setting, and give a single round delegation scheme for the class NC1, of search problems...... computable by log-space uniform circuits of logarithmic depth, with a sub-linear time verifier. While our approach provides a weaker (yet arguably meaningful) guarantee of soundness, it compares favorably with each of the known delegation schemes in at least one aspect. Our protocols are simple, rely...

  8. A secured Cryptographic Hashing Algorithm

    CERN Document Server

    Mohanty, Rakesh; Bishi, Sukant kumar

    2010-01-01

    Cryptographic hash functions for calculating the message digest of a message has been in practical use as an effective measure to maintain message integrity since a few decades. This message digest is unique, irreversible and avoids all types of collisions for any given input string. The message digest calculated from this algorithm is propagated in the communication medium along with the original message from the sender side and on the receiver side integrity of the message can be verified by recalculating the message digest of the received message and comparing the two digest values. In this paper we have designed and developed a new algorithm for calculating the message digest of any message and implemented t using a high level programming language. An experimental analysis and comparison with the existing MD5 hashing algorithm, which is predominantly being used as a cryptographic hashing tool, shows this algorithm to provide more randomness and greater strength from intrusion attacks. In this algorithm th...

  9. Raptor Codes and Cryptographic Issues

    CERN Document Server

    Malinen, Mikko

    2008-01-01

    In this paper two cryptographic methods are introduced. In the first method the presence of a certain size subgroup of persons can be checked for an action to take place. For this we use fragments of Raptor codes delivered to the group members. In the other method a selection of a subset of objects can be made secret. Also, it can be proven afterwards, what the original selection was.

  10. Symmetric cryptographic protocols

    CERN Document Server

    Ramkumar, Mahalingam

    2014-01-01

    This book focuses on protocols and constructions that make good use of symmetric pseudo random functions (PRF) like block ciphers and hash functions - the building blocks for symmetric cryptography. Readers will benefit from detailed discussion of several strategies for utilizing symmetric PRFs. Coverage includes various key distribution strategies for unicast, broadcast and multicast security, and strategies for constructing efficient digests of dynamic databases using binary hash trees.   •        Provides detailed coverage of symmetric key protocols •        Describes various applications of symmetric building blocks •        Includes strategies for constructing compact and efficient digests of dynamic databases

  11. Public health - threats, concerns and key actions

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    Public health is discussed departing from priorities related to the precautionary principle with special reference to air pollution from wood burning in individual stoves and the susceptibility of vulnerable groups, i.a. people with genetic predispositions for a lack of detoxifying capacity....

  12. Public health - threats, concerns and key actions

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf

    Public health is discussed departing from priorities related to the precautionary principle with special reference to air pollution from wood burning in individual stoves and the susceptibility of vulnerable groups, i.a. people with genetic predispositions for a lack of detoxifying capacity....

  13. Public key cryptosystem and a key exchange protocol using tools of non-abelian group

    Directory of Open Access Journals (Sweden)

    H. K. Pathak,

    2010-07-01

    Full Text Available Public Key Cryptosystems assure privacy as well as integrity of the transactions between two parties. The sizes of the keys play an important role. The larger the key the harder is to crack a block ofencrypted data. We propose a new public key cryptosystem and a Key Exchange Protocol based on the generalization of discrete logarithm problem using Non-abelian group of block upper triangular matrices of higher order. The proposed cryptosystem is efficient in producing keys of large sizes without the need of large primes. The security of both the systems relies on the difficulty of discrete logarithms over finite fields.

  14. Summary Report on Rational Cryptographic Protocols

    DEFF Research Database (Denmark)

    Alwen, Joël; Cachin, Christian; Pereira, Olivier

    This report gives an overview of some of the models and techniques in rational cryptography, an emerging research area which in particular uses the methodologies and techniques of game theory to analyze cryptographic protocols and which uses cryptographic protocol theory to implement game theoretic...

  15. Public-Key Encryption with Non-interactive Opening

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Hofheinz, Dennis; Kiltz, Eike

    2008-01-01

    in cryptographic protocol design, e.g., when the receiver wants to demonstrate that some information he was sent privately was not correctly formed. We give a definition based on the UC framework as well as an equivalent game-based definition. The PKENO concept was informally introduced by Damgård and Thorbek who...

  16. The Laws of Physics and Cryptographic Security

    CERN Document Server

    Rudolph, T

    2002-01-01

    This paper consists of musings that originate mainly from conversations with other physicists, as together we've tried to learn some cryptography, but also from conversations with a couple of classical cryptographers. The main thrust of the paper is an attempt to explore the ramifications for cryptographic security of incorporating physics into our thinking at every level. I begin by discussing two fundamental cryptographic principles, namely that security must not rely on secrecy of the protocol and that our local environment must be secure, from a physical perspective. I go on to explain why by definition a particular cryptographic task, oblivious transfer, is inconsistent with a belief in the validity of quantum mechanics. More precisely, oblivious transfer defines states and operations that do not exist in any (complex) Hilbert space. I go on to argue the fallaciousness of a "black box" approach to quantum cryptography, in which classical cryptographers just trust physicists to provide them with secure qu...

  17. Distributed public key schemes secure against continual leakage

    DEFF Research Database (Denmark)

    Akavia, Adi; Goldwasser, Shafi; Hazay, Carmit

    2012-01-01

    In this work we study distributed public key schemes secure against continual memory leakage. The secret key will be shared among two computing devices communicating over a public channel, and the decryption operation will be computed by a simple 2-party protocol between the devices. Similarly...... the value of the respective function on the internal state of the respective device (namely, on its secret share, internal randomness, and results of intermediate computations). We present distributed public key encryption (DPKE) and distributed identity based encryption (DIBE) schemes that are secure...

  18. Cryptographic Protocols under Quantum Attacks

    CERN Document Server

    Lunemann, Carolin

    2011-01-01

    The realm of this thesis is cryptographic protocol theory in the quantum world. We study the security of quantum and classical protocols against adversaries that are assumed to exploit quantum effects to their advantage. Security in the quantum world means that quantum computation does not jeopardize the assumption, underlying the protocol construction. But moreover, we encounter additional setbacks in the security proofs, which are mostly due to the fact that some well-known classical proof techniques are forbidden by certain properties of a quantum environment. Interestingly, we can exploit some of the very same properties to the benefit of quantum cryptography. Thus, this work lies right at the heart of the conflict between highly potential effects but likewise rather demanding conditions in the quantum world.

  19. A Secure Public-key Image Authentication Plan

    Institute of Scientific and Technical Information of China (English)

    YANG Qing; CHEN Ke-fei

    2005-01-01

    Digital watermark can be used for image ownership verification or authentication. In this paper, we propose a new image authentication plan concentrating on its security performance. Digital watermark is first turbo coded, scaled and then processed in wavelet domain. To enhance security level, public key cryptosystem is utilized to replace traditional watermark key. Simulation results are finally given by experiment.

  20. A Survey of Key Technology of Network Public Opinion Analysis

    Directory of Open Access Journals (Sweden)

    Li Su Ying

    2016-01-01

    Full Text Available The internet has become an important base for internet users to make comments because of its interactivity and fast dissemination. The outbreak of internet public opinion has become a major risk for network information security. Domestic and foreign researchers had carried out extensive and in-depth study on public opinion. Fruitful results have achieved in the basic theory research and emergency handling and other aspects of public opinion. But research on the public opinion in China is still in the initial stage, the key technology of the public opinion analysis is still as a starting point for in-depth study and discussion.

  1. A public-key cryptosystem for quantum message transmission

    Science.gov (United States)

    Yang, Li

    2005-01-01

    We present a quantum public-key cryptography protocol for quantum message transmission. The private key of this protocol includes three classical matrices: a generator matrix of a Goppa code, an invertible matrix and a permutation matrix. The public key is product of these three matrices. The encryption and decryption algorithms are merely quantum computations related with the transformations between bases of the quantum registers. The security of this protocol is based on the hypothesis that there is no effective algorithm of NP-complete problem.

  2. Public-key cryptography in functional programming context

    CERN Document Server

    Márton, Gyöngyvér

    2010-01-01

    Up to now, for efficiency reasons cryptographic algorithm has been written in an imperative language. But to get acquaintance with a functional programming language a question arises: functional programming offers some new for secure communication or not? This article investigates this question giving an overview on some cryptography algorithms and presents how the RSA encryption in the functional language Clean can be implemented and how can be measured the efficiency of a certain application.

  3. LPKI - A Lightweight Public Key Infrastructure for the Mobile Environments

    CERN Document Server

    Toorani, Mohsen; 10.1109/ICCS.2008.4737164

    2010-01-01

    The non-repudiation as an essential requirement of many applications can be provided by the asymmetric key model. With the evolution of new applications such as mobile commerce, it is essential to provide secure and efficient solutions for the mobile environments. The traditional public key cryptography involves huge computational costs and is not so suitable for the resource-constrained platforms. The elliptic curve-based approaches as the newer solutions require certain considerations that are not taken into account in the traditional public key infrastructures. The main contribution of this paper is to introduce a Lightweight Public Key Infrastructure (LPKI) for the constrained platforms such as mobile phones. It takes advantages of elliptic curve cryptography and signcryption to decrease the computational costs and communication overheads, and adapting to the constraints. All the computational costs of required validations can be eliminated from end-entities by introduction of a validation authority to th...

  4. Quantum key management

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, Richard John; Thrasher, James Thomas; Nordholt, Jane Elizabeth

    2016-11-29

    Innovations for quantum key management harness quantum communications to form a cryptography system within a public key infrastructure framework. In example implementations, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a Merkle signature scheme (using Winternitz one-time digital signatures or other one-time digital signatures, and Merkle hash trees) to constitute a cryptography system. More generally, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a hash-based signature scheme. This provides a secure way to identify, authenticate, verify, and exchange secret cryptographic keys. Features of the quantum key management innovations further include secure enrollment of users with a registration authority, as well as credential checking and revocation with a certificate authority, where the registration authority and/or certificate authority can be part of the same system as a trusted authority for quantum key distribution.

  5. Quantum key management

    Science.gov (United States)

    Hughes, Richard John; Thrasher, James Thomas; Nordholt, Jane Elizabeth

    2016-11-29

    Innovations for quantum key management harness quantum communications to form a cryptography system within a public key infrastructure framework. In example implementations, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a Merkle signature scheme (using Winternitz one-time digital signatures or other one-time digital signatures, and Merkle hash trees) to constitute a cryptography system. More generally, the quantum key management innovations combine quantum key distribution and a quantum identification protocol with a hash-based signature scheme. This provides a secure way to identify, authenticate, verify, and exchange secret cryptographic keys. Features of the quantum key management innovations further include secure enrollment of users with a registration authority, as well as credential checking and revocation with a certificate authority, where the registration authority and/or certificate authority can be part of the same system as a trusted authority for quantum key distribution.

  6. Public key infrastructure building trusted applications and web services

    CERN Document Server

    Vacca, John R

    2004-01-01

    OVERVIEW OF PKI TECHNOLOGYPublic Key Infrastructures (PKIs): What Are They?Type of Certificate Authorities (CAS) ServicesPKI StandardsTypes of Vendor and Third-Party CA SystemsProtecting Private KeysCA System AttacksStolen Private Keys: What Can Be Done?Certificate Practice StatementsPKI ReadinessANALYZING AND DESIGNING PUBLIC KEY INFRASTRUCTURESPKI Design IssuesCost Justification and ConsiderationPKI Standards Design IssuesPKI Architectural Design ConsiderationsIMPLEMENTING PKIRequirementsImplementation ScheduleImplementation CostsPKI PerformanceMANAGING PKIRequesting a CertificateObtaining a

  7. A Rational Approach to Cryptographic Protocols

    CERN Document Server

    Caballero-Gil, P; Bruno-Castañeda, C; 10.1016/j.mcm.2006.12.013

    2010-01-01

    This work initiates an analysis of several cryptographic protocols from a rational point of view using a game-theoretical approach, which allows us to represent not only the protocols but also possible misbehaviours of parties. Concretely, several concepts of two-person games and of two-party cryptographic protocols are here combined in order to model the latters as the formers. One of the main advantages of analysing a cryptographic protocol in the game-theory setting is the possibility of describing improved and stronger cryptographic solutions because possible adversarial behaviours may be taken into account directly. With those tools, protocols can be studied in a malicious model in order to find equilibrium conditions that make possible to protect honest parties against all possible strategies of adversaries.

  8. A Public Key Block Cipher Based on Multivariate Quadratic Quasigroups

    CERN Document Server

    Gligoroski, Danilo; Knapskog, Svein Johan

    2008-01-01

    We have designed a new class of public key algorithms based on quasigroup string transformations using a specific class of quasigroups called multivariate quadratic quasigroups (MQQ). Our public key algorithm is a bijective mapping, it does not perform message expansions and can be used both for encryption and signatures. The public key consist of n quadratic polynomials with n variables where n=140, 160, ... . A particular characteristic of our public key algorithm is that it is very fast and highly parallelizable. More concretely, it has the speed of a typical modern symmetric block cipher - the reason for the phrase "A Public Key Block Cipher" in the title of this paper. Namely the reference C code for the 160-bit variant of the algorithm performs decryption in less than 11,000 cycles (on Intel Core 2 Duo -- using only one processor core), and around 6,000 cycles using two CPU cores and OpenMP 2.0 library. However, implemented in Xilinx Virtex-5 FPGA that is running on 249.4 MHz it achieves decryption thro...

  9. Construction and analysis of cryptographic functions

    CERN Document Server

    Budaghyan, Lilya

    2015-01-01

    This book covers novel research on construction and analysis of optimal cryptographic functions such as almost perfect nonlinear (APN), almost bent (AB), planar and bent functions. These functions have optimal resistance to linear and/or differential attacks, which are the two most powerful attacks on symmetric cryptosystems. Besides cryptographic applications, these functions are significant in many branches of mathematics and information theory including coding theory, combinatorics, commutative algebra, finite geometry, sequence design and quantum information theory. The author analyzes equ

  10. Modeling, Simulation and Analysis of Public Key Infrastructure

    Science.gov (United States)

    Liu, Yuan-Kwei; Tuey, Richard; Ma, Paul (Technical Monitor)

    1998-01-01

    Security is an essential part of network communication. The advances in cryptography have provided solutions to many of the network security requirements. Public Key Infrastructure (PKI) is the foundation of the cryptography applications. The main objective of this research is to design a model to simulate a reliable, scalable, manageable, and high-performance public key infrastructure. We build a model to simulate the NASA public key infrastructure by using SimProcess and MatLab Software. The simulation is from top level all the way down to the computation needed for encryption, decryption, digital signature, and secure web server. The application of secure web server could be utilized in wireless communications. The results of the simulation are analyzed and confirmed by using queueing theory.

  11. SPEED AND SECURITY ENHANCEMENT THROUGH PUBLIC KEY CRYPTOGRAPHY

    Directory of Open Access Journals (Sweden)

    J.SAIGEETHA

    2010-08-01

    Full Text Available It is true that the transfer of data is essential in the fast developing world. It is equally true that the transfer of data tobe taken place with much security by not giving groom to the intruders. This paper presents the analysis of the security of information with enhanced the speed of encryption and decryption process. This process uses public key cryptography via RSA algorithm with some modification. There are two keys used in RSA algorithm foreffectiveness in the aspect of security one being the public key used for all and the other being the secret key. The implementation is done in the JAVA language and crypt analysis is performed to check the level of protection and speed .

  12. Public Key Infrastructure Increment 2 (PKI Inc 2)

    Science.gov (United States)

    2016-03-01

    Public Key Infrastructure (PKI) is a critical enabling technology for Information Assurance (IA) services to support seamless secure information flows...resources. 6. Integrity of software used within or transmitted over DoD networks (i.e. mobile code,) and the provision of security services within the...Operational Capability IP - Internet Protocol IT - Information Technology KPP - Key Performance Parameter $M - Millions of Dollars MAIS - Major

  13. William Friedman, Geneticist Turned Cryptographer.

    Science.gov (United States)

    Goldman, Irwin L

    2017-05-01

    William Friedman (1891-1969), trained as a plant geneticist at Cornell University, was employed at Riverbank Laboratories by the eccentric millionaire George Fabyan to work on wheat breeding. Friedman, however, soon became intrigued by and started working on a pet project of Fabyan's involving the conjecture that Francis Bacon, a polymath known for the study of ciphers, was the real author of Shakespeare's plays. Thus, beginning in ∼1916, Friedman turned his attention to the so called "Baconian cipher," and developed decryption techniques that bore similarity to approaches for solving problems in population genetics. His most significant, indeed pathbreaking, work used ideas from genetics and statistics, focusing on analysis of the frequencies of letters in language use. Although he had transitioned from being a geneticist to a cryptographer, his earlier work had resonance in his later pursuits. He soon began working directly for the United States government and produced solutions used to solve complex military ciphers, in particular to break the Japanese Purple code during World War II. Another important legacy of his work was the establishment of the Signal Intelligence Service and eventually the National Security Agency. Copyright © 2017 by the Genetics Society of America.

  14. Public-key Encryption with Registered Keyword Search

    NARCIS (Netherlands)

    Tang, Qiang; Chen, Liqun

    Public-key Encryption with Keyword Search (PEKS) enables a server to test whether a tag from a sender and a trapdoor from a receiver contain the same keyword. In this paper, we highlight some potential security concern, i.e. a curious server is able to answer whether any selected keyword is

  15. An investigation of DUA caching strategies for public key certificates

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, T.C.

    1993-11-01

    Internet Privacy Enhanced Mail (PEM) provides security services to users of Internet electronic mail. PEM is designed with the intention that it will eventually obtain public key certificates from the X.500 directory service. However, such a capability is not present in most PEM implementations today. While the prevalent PEM implementation uses a public key certificate-based strategy, certificates are mostly distributed via e-mail exchanges, which raises several security and performance issues. In this thesis research, we changed the reference PEM implementation to make use of the X.500 directory service instead of local databases for public key certificate management. The thesis discusses some problems with using the X.500 directory service, explores the relevant issues, and develops an approach to address them. The approach makes use of a memory cache to store public key certificates. We implemented a centralized cache server and addressed the denial-of-service security problem that is present in the server. In designing the cache, we investigated several cache management strategies. One result of our study is that the use of a cache significantly improves performance. Our research also indicates that security incurs extra performance cost. Different cache replacement algorithms do not seem to yield significant performance differences, while delaying dirty-writes to the backing store does improve performance over immediate writes.

  16. Cryptanalysis on a finite automaton public key cryptosystem

    Institute of Scientific and Technical Information of China (English)

    戴大为; 吴逵; 张焕国

    1996-01-01

    An attack algorithm is proposed on a finite automaton public key cryptosystem.It is proved that this attack can break FAPKCO in polynomial time.The basic idea can be used in principle to attack other FAPKCs.Therefore,while designing an FAPKC,it must be taken into account whether it is secure or not under this kind of attack.

  17. Public Key Cryptography Based on Ergodic Matrices over Finite Field

    Institute of Scientific and Technical Information of China (English)

    PEI Shihui; ZHAO Hongwei; ZHAO Yongzhe

    2006-01-01

    A new public key encryption scheme is proposed in this paper, which is based on a hard problem over ergodic matrices. The security of this scheme is equal to the MQ-problem: multivariate quadratic equations over finite fields. This problem has been shown to be NP-complete and can' be solved with polynomial time algorithm.

  18. Trellis-coded quantization for public-key steganography

    CERN Document Server

    Guelvouit, Gaëtan Le

    2008-01-01

    This paper deals with public-key steganography in the presence of a passive warden. The aim is to hide secret messages within cover-documents without making the warden suspicious, and without any preliminar secret key sharing. Whereas a practical attempt has been already done to provide a solution to this problem, it suffers of poor flexibility (since embedding and decoding steps highly depend on cover-signals statistics) and of little capacity compared to recent data hiding techniques. Using the same framework, this paper explores the use of trellis-coded quantization techniques (TCQ and turbo TCQ) to design a more efficient public-key scheme. Experiments on audio signals show great improvements considering Cachin's security criterion.

  19. Little Dragon Two: An efficient Multivariate Public Key Cryptosystem

    Directory of Open Access Journals (Sweden)

    Rajesh P Singh

    2010-04-01

    Full Text Available In 1998 [8], Patarin proposed an efficient cryptosystem called Little Dragon which was a variant a variant of Matsumoto Imai cryptosystem C*. However Patarin latter found that Little Dragon cryptosystem is not secure [8], [3]. In this paper we propose a cryptosystem Little Dragon Two which is as efficient as Little Dragon cryptosystem but secure against all the known attacks. Like Little Dragon cryptosystem the public key of Little Dragon Two is mixed type that is quadratic in plaintext and cipher text variables. So the public key size of Little Dragon Two is equal to Little Dragon Cryptosystem. Ourpublic key algorithm is bijective and can be used for both encryption and signatures

  20. A New Factorization Method to Factorize RSA Public Key Encryption

    Directory of Open Access Journals (Sweden)

    Bhagvant Ram Ambedkar

    2011-11-01

    Full Text Available The security of public key encryption such as RSA scheme relied on the integer factoring problem. The security of RSA algorithm is based on positive integer N, because each transmitting node generates pair of keys such as public and private. Encryption and decryption of any message depends on N. Where, N is the product of two prime numbers and pair of key generation is dependent on these prime numbers. The factorization of N is very intricate. In this paper a New Factorization method is proposed to obtain the factor of positive integer N. The proposed work focuses on factorization of all trivial and nontrivial integer numbers and requires fewer steps for factorization process of RSA modulus N. The New Factorization method is based on Pollard rho factorization method. Experimental results shown that factorization speed is fast as compare existing methods.

  1. Efficient quantum secure communication with a publicly known key

    Institute of Scientific and Technical Information of China (English)

    Li Chun-Yan; Li Xi-Han; Deng Fu-Guo; Zhou Hong-Yu

    2008-01-01

    This paper presents a simple way for an eavesdropper to eavesdrop freely the secret message in the experimental realization of quantum communication protocol proposed by Beige et al (2002 Acta Phys. Pol. A 101 357). Moreover, it introduces an efficient quantum secure communication protocol based on a publicly known key with decoy photons and two biased bases by modifying the original protocol. The total efficiency of this new protocol is double that of the original one. With a low noise quantum channel, this protocol can be used for transmitting a secret message. At present, this protocol is good for generating a private key efficiently.

  2. An application of different dioids in public key cryptography

    Energy Technology Data Exchange (ETDEWEB)

    Durcheva, Mariana I., E-mail: mdurcheva66@gmail.com [Technical University of Sofia, Faculty of Applied Mathematics and Informatics, 8 Kliment Ohridski St., Sofia 1000 (Bulgaria)

    2014-11-18

    Dioids provide a natural framework for analyzing a broad class of discrete event dynamical systems such as the design and analysis of bus and railway timetables, scheduling of high-throughput industrial processes, solution of combinatorial optimization problems, the analysis and improvement of flow systems in communication networks. They have appeared in several branches of mathematics such as functional analysis, optimization, stochastic systems and dynamic programming, tropical geometry, fuzzy logic. In this paper we show how to involve dioids in public key cryptography. The main goal is to create key – exchange protocols based on dioids. Additionally the digital signature scheme is presented.

  3. Key-phrase based classification of public health web pages.

    Science.gov (United States)

    Dolamic, Ljiljana; Boyer, Célia

    2013-01-01

    This paper describes and evaluates the public health web pages classification model based on key phrase extraction and matching. Easily extendible both in terms of new classes as well as the new language this method proves to be a good solution for text classification faced with the total lack of training data. To evaluate the proposed solution we have used a small collection of public health related web pages created by a double blind manual classification. Our experiments have shown that by choosing the adequate threshold value the desired value for either precision or recall can be achieved.

  4. Asymmetric Unification: A New Unification Paradigm for Cryptographic Protocol Analysis

    OpenAIRE

    2013-01-01

    The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-38574-2_16 We present a new paradigm for unification arising out of a technique commonly used in cryptographic protocol analysis tools that employ unification modulo equational theories. This paradigm relies on: (i) a decomposition of an equational theory into (R,E) where R is confluent, terminating, and coherent modulo E, and (ii) on reducing unification problems to a set of problems s=?ts=?t under the ...

  5. Secure Internet Voting System based on Public Key Kerberos

    Directory of Open Access Journals (Sweden)

    Hussein Khalid Abd-Alrazzq

    2012-03-01

    Full Text Available Electronic voting system is an important tool which allows voters to vote over the Internet without the geographical restrictions with considers important criteria in evaluating electronic voting schemes such as the mobility, democracy, and privacy. In this paper secure remote voting system has been presented. The proposed system uses public key Kerberos which is another form of traditional Kerberos as infrastructure deal with voters. The public key is used in all steps of Kerberos (not only in initial. The proposed system utilizes the advantages of threshold cryptography to prevent anyone to decrypt or sign the ballot alone without agreement all authorities, and use threshold blind signature to prevent discovers the vote or the identity of voter and protect the content of the ballot during casting and provide verifiable and discourages ballot buying.

  6. Review of Lattice-based Public key Cryptography(Russian)

    OpenAIRE

    Usatyuk, V. S.

    2010-01-01

    This article presets a review of the achievements rapidly developing field of cryptography - public-key cryptography based on the lattice theory. Paper contains the necessary basic concepts and the major problems of the lattice theory, as well as together with the description on the benefits of this cryptography class - the properties of the reliability to quantum computers and full homomorphism, the shortcomings of specific implementations.

  7. Chaotic cryptographic scheme and its randomness evaluation

    Science.gov (United States)

    Stoyanov, B. P.

    2012-10-01

    We propose a new cryptographic scheme based on the Lorenz chaos attractor and 32 bit bent Boolean function. We evaluated the keystream generated by the scheme with batteries of the NIST statistical tests. We also applied a number of statistical analysis techniques, such as calculating histograms, correlations between two adjacent pixels, information entropy, and differential resistance, all refer to images encrypted by the proposed system. The results of the analysis show that the new cryptographic scheme ensures a secure way for sending digital data with potential applications in real-time image encryption.

  8. PROPERTIES AND APPROACH OF CRYPTOGRAPHIC HASH ALGORITHMS

    Directory of Open Access Journals (Sweden)

    T.LALITHA

    2010-06-01

    Full Text Available The importance of hash functions for protecting the authenticity of information is demonstrated. Applications include integrity protection, conventional message authentication and digital signatures. An overview is given of the study of basic building blocks of cryptographic hash functions leads to the study of the cryptographic properties of Boolean functions and the information theoretic approach to authentication is described. An overview is given of the complexity theoretic definitions and constructions .New criteria are defined and functions satisfying new and existing criteria are studied.

  9. Cryptographic primitives based on cellular transformations

    Directory of Open Access Journals (Sweden)

    B.V. Izotov

    2003-11-01

    Full Text Available Design of cryptographic primitives based on the concept of cellular automata (CA is likely to be a promising trend in cryptography. In this paper, the improved method performing data transformations by using invertible cyclic CAs (CCA is considered. Besides, the cellular operations (CO as a novel CAs application in the block ciphers are introduced. Proposed CCAs and COs, integrated under the name of cellular transformations (CT, suit well to be used in cryptographic algorithms oriented to fast software and cheap hardware implementation.

  10. Noncoherent capacity of secret-key agreement with public discussion

    KAUST Repository

    Agrawal, Anurag

    2011-09-01

    We study the noncoherent capacity of secret-key agreement with public discussion over independent identically distributed (i.i.d.) Rayleigh fading wireless channels, where neither the sender nor the receivers have access to instantaneous channel state information (CSI). We present two results. At high signal-to-noise ratio (SNR), the secret-key capacity is bounded in SNR, regardless of the number of antennas at each terminal. Second, for a system with a single antenna at both the legitimate and the eavesdropper terminals and an arbitrary number of transmit antennas, the secret-key capacity-achieving input distribution is discrete, with a finite number of mass points. Numerically we observe that at low SNR, the capacity achieving distribution has two mass points with one of them at the origin. © 2011 IEEE.

  11. A Verifiable Language for Cryptographic Protocols

    DEFF Research Database (Denmark)

    Nielsen, Christoffer Rosenkilde

    We develop a formal language for specifying cryptographic protocols in a structured and clear manner, which allows verification of many interesting properties; in particular confidentiality and integrity. The study sheds new light on the problem of creating intuitive and human readable languages...

  12. Anonymous-key quantum cryptography and unconditionally secure quantum bit commitment

    CERN Document Server

    Yuen, H P

    2000-01-01

    A new cryptographic tool, anonymous quantum key technique, is introduced that leads to unconditionally secure key distribution and encryption schemes that can be readily implemented experimentally in a realistic environment. If quantum memory is available, the technique would have many features of public-key cryptography; an identification protocol that does not require a shared secret key is provided as an illustration. The possibility is also indicated for obtaining unconditionally secure quantum bit commitment protocols with this technique.

  13. Some Attacks On Quantum-based Cryptographic Protocols

    CERN Document Server

    Lo, H K; Lo, Hoi-Kwong; Ko, Tsz-Mei

    2003-01-01

    Quantum-based cryptographic protocols are often said to enjoy security guaranteed by the fundamental laws of physics. However, subtle attacks that are outside the original design of the protocols may allow eavesdroppers to break those protocols. As an example, we will give a peeking attack against a quantum key distribution scheme based on quantum memory. Moreover, if technological assumptions are made in the design of a quantum-based cryptographic protocol, then the actual security of the protocol may fall short of expectations. This is because it is often hard to quantify those technological assumptions in a precise manner. Here, we give an attack against a recently proposed ``secure communication using coherent state scheme''. Our attack requires only beamsplitters and the replacement of a lossy channel by a lossless one. It is successful provided that the original loss in the channel is so big that Eve can obtain 2^k copies of what Bob receives, where k is the length of the seed key pre-shared by Alice an...

  14. Lower and Upper Bounds for Deniable Public-Key Encryption

    DEFF Research Database (Denmark)

    Bendlin, Rikke; Nielsen, Jesper Buus; Nordholt, Peter Sebastian

    2011-01-01

    the parties to change their internal state to make it look like a given ciphertext decrypts to a message different from what it really decrypts to. Deniable encryption was in this way introduced to allow to deny a message exchange and hence combat coercion. Depending on which parties can be coerced......, the security level, the flavor and the number of rounds of the cryptosystem, it is possible to define a number of notions of deniable encryption. In this paper we prove that there does not exist any non-interactive receiver-deniable cryptosystem with better than polynomial security. This also shows...... that it is impossible to construct a non-interactive bi-deniable public-key encryption scheme with better than polynomial security. Specifically, we give an explicit bound relating the security of the scheme to how efficient the scheme is in terms of key size. Our impossibility result establishes a lower bound...

  15. Error-correcting pairs for a public-key cryptosystem

    Science.gov (United States)

    Pellikaan, Ruud; Márquez-Corbella, Irene

    2017-06-01

    Code-based Cryptography (CBC) is a powerful and promising alternative for quantum resistant cryptography. Indeed, together with lattice-based cryptography, multivariate cryptography and hash-based cryptography are the principal available techniques for post-quantum cryptography. CBC was first introduced by McEliece where he designed one of the most efficient Public-Key encryption schemes with exceptionally strong security guarantees and other desirable properties that still resist to attacks based on Quantum Fourier Transform and Amplitude Amplification. The original proposal, which remains unbroken, was based on binary Goppa codes. Later, several families of codes have been proposed in order to reduce the key size. Some of these alternatives have already been broken. One of the main requirements of a code-based cryptosystem is having high performance t-bounded decoding algorithms which is achieved in the case the code has a t-error-correcting pair (ECP). Indeed, those McEliece schemes that use GRS codes, BCH, Goppa and algebraic geometry codes are in fact using an error-correcting pair as a secret key. That is, the security of these Public-Key Cryptosystems is not only based on the inherent intractability of bounded distance decoding but also on the assumption that it is difficult to retrieve efficiently an error-correcting pair. In this paper, the class of codes with a t-ECP is proposed for the McEliece cryptosystem. Moreover, we study the hardness of distinguishing arbitrary codes from those having a t-error correcting pair.

  16. 75 FR 20364 - Public Buildings Service; Key Largo Beacon Annex Site; Key Largo, FL; Transfer of Property

    Science.gov (United States)

    2010-04-19

    ... From the Federal Register Online via the Government Publishing Office GENERAL SERVICES ADMINISTRATION Public Buildings Service; Key Largo Beacon Annex Site; Key Largo, FL; Transfer of Property..., identified as Key Largo Beacon Annex Site, Key Largo, FL to the U.S. Fish and Wildlife Service, Department...

  17. Appliance of Neuron Networks in Cryptographic Systems

    Directory of Open Access Journals (Sweden)

    Mohammed Al-Maitah

    2014-01-01

    Full Text Available This study is dedicated to the examination of a problem of postquantum encryption algorithms which are connected with a potential crisis in modern cryptography that is caused by appearance of quantum computers. General problem formulation is given as well as an example of danger from the quantum algorithms against classical cryptosystems. Existing postquantum systems are analyzed and the complication of their realization and cryptosecurity are estimated. Among the others algorithms on the basis of neural networks are chosen as a starting point. The study demonstrates neuro cryptographic protocol based on a three-level neural network of the direct propagation. There was evaluated it’s cryptosecurity and analyzed three types of this algorithm attack to show the reality of the hypothesis that neuro cryptography is currently one of the most promising post quantum cryptographic systems.

  18. Algebra model and security analysis for cryptographic protocols

    Institute of Scientific and Technical Information of China (English)

    HUAI Jinpeng; LI Xianxian

    2004-01-01

    More and more cryptographic protocols have been used to achieve various security requirements of distributed systems in the open network environment. However cryptographic protocols are very difficult to design and analyze due to the complexity of the cryptographic protocol execution, and a large number of problems are unsolved that range from the theory framework to the concrete analysis technique. In this paper, we build a new algebra called cryptographic protocol algebra (CPA) for describing the message operations with many cryptographic primitives, and proposed a new algebra model for cryptographic protocols based on the CPA. In the model, expanding processes of the participant's knowledge on the protocol runs are characterized with some algebraic notions such as subalgebra, free generator and polynomial algebra, and attack processes are modeled with a new notion similar to that of the exact sequence used in homological algebra. Then we develope a mathematical approach to the cryptographic protocol security analysis. By using algebraic techniques, we have shown that for those cryptographic protocols with some symmetric properties, the execution space generated by an arbitrary number of participants may boil down to a smaller space generated by several honest participants and attackers. Furthermore we discuss the composability problem of cryptographic protocols and give a sufficient condition under which the protocol composed of two correct cryptographic protocols is still correct, and we finally offer a counterexample to show that the statement may not be true when the condition is not met.

  19. Towards Public Key Infrastructure less authentication in Session Initiation Protocol

    Directory of Open Access Journals (Sweden)

    Md. Sarwar Morshed

    2010-01-01

    Full Text Available The Session Initiation Protocol (SIP has become the most predominant protocol for Voice over Internet Protocol (VoIP signaling. Security of SIP is an important consideration for VoIP communication as the traffic is transmitted over the insecure IP network. And the authentication process in SIP ranges from pre-shared secret based solutions to Public Key Infrastructure (PKI based solution. However, due to the limitations in PKI based solutions, some PKI less authentications mechanisms are proposed. This paper aims to present an overview of different authentication methods used in or together with SIP. We start by highlighting the security issues in SIP in the context of VoIP communication. Then we illustrate the current activities regarding the SIP authentication mechanisms including the recent developments in the research community and standardization efforts within the Internet Engineering Task Force (IETF. Finally we analyze the security aspects of these approaches.

  20. Towards Public Key Infrastructure less authentication in Session Initiation Protocol

    CERN Document Server

    Hasib, Abdullah Al; Morshed, Md Sarwar

    2010-01-01

    The Session Initiation Protocol (SIP) has become the most predominant protocol for Voice over Internet Protocol (VoIP) signaling. Security of SIP is an important consideration for VoIP communication as the traffic is transmitted over the insecure IP network. And the authentication process in SIP ranges from pre-shared secret based solutions to Public Key Infrastructure (PKI) based solution. However, due to the limitations in PKI based solutions, some PKI less authentications mechanisms are proposed. This paper aims to present an overview of different authentication methods used in or together with SIP. We start by highlighting the security issues in SIP in the context of VoIP communication. Then we illustrate the current activities regarding the SIP authentication mechanisms including the recent developments in the research community and standardization efforts within the Internet Engineering Task Force (IETF). Finally we analyze the security aspects of these approaches.

  1. Cryptographic hash functions. Trends and challenges

    Directory of Open Access Journals (Sweden)

    Rodica Tirtea

    2009-10-01

    Full Text Available Hash functions are important in cryptography due to their use in data integrity and message authentication. Different cryptographicimplementations rely on the performance and strength of hash functions to answer the need for integrity and authentication. This paper gives an overview of cryptographic hash functions used or evaluated today. Hash functions selected in NESSIE and CRYPTREC projects are shortly presented. SHA-3 selection initiative is alsointroduced.

  2. PACE: Proactively Secure Accumulo with Cryptographic Enforcement

    Science.gov (United States)

    2017-05-27

    modify data using digital signatures . The contributions of our work include: • Cryptographic enforcement of access control. The PACE library allows...the impact of encryption and signatures on operation throughput. I. INTRODUCTION Over the last several years, many companies have moved their...second). This evaluation demonstrates that while encryp- tion and signatures have an impact on throughput, the impact is small enough to be

  3. Mechanical Verification of Cryptographic Protocols

    Science.gov (United States)

    Cheng, Xiaochun; Ma, Xiaoqi; Huang, Scott C.-H.; Cheng, Maggie

    Information security is playing an increasingly important role in modern society, driven especially by the uptake of the Internet for information transfer. Large amount of information is transmitted everyday through the Internet, which is often the target of malicious attacks. In certain areas, this issue is vital. For example, military departments of governments often transmit a great amount of top-secret data, which, if divulged, could become a huge threat to the public and to national security. Even in our daily life, it is also necessary to protect information. Consider e-commerce systems as an example. No one is willing to purchase anything over the Internet before being assured that all their personal and financial information will always be kept secure and will never be leaked to any unauthorised person or organisation.

  4. CRYPTOGRAPHIC PROTOCOLS SPECIFICATION AND VERIFICATION TOOLS - A SURVEY

    Directory of Open Access Journals (Sweden)

    Amol H Shinde

    2017-06-01

    Full Text Available Cryptographic protocols cannot guarantee the secure operations by merely using state-of-the-art cryptographic mechanisms. Validation of such protocols is done by using formal methods. Various specialized tools have been developed for this purpose and are being used to validate real life cryptographic protocols. These tools give feedback to the designers of protocols in terms of loops and attacks in protocols to improve security. In this paper, we discuss the brief history of formal methods and tools that are useful for the formal verification of the cryptographic protocols.

  5. A Trusted Centralized Public Key to Secure Border Gateway Protocol

    Directory of Open Access Journals (Sweden)

    Divan Raimagia

    2012-06-01

    Full Text Available The Secure Border Gateway Protocol (S-BGP is used when two different Autonomous System communicate with each other and upon reception of UPDATE from neighbor Autonomous System. A core layer Router in single Autonomous System called BGP speaker first verifies the receiving update and signs the full path with own digital signature and send it to neighbor AS. In Real scenario so many ASes and Routers communicate to each other. So due to several digital signatures mandates, large storage require in router as well as high processor overhead and more time require for sign generation and verification in S-BGP. In this paper, we propose a new approach that less burden on BGP Speaker for verify and generate number of digital signatures using Autonomous System makes trusted through KDC server. The Central KDC Server will send master certificate to validate autonomous system. In this environment each BGP speaker verify only one sign on each update and verify path only between itself and neighbor router. After verification of UPDATE, each BGP speaker sign full path encrypt routing table with neighbor’s public key,

  6. Virtual microscopy and public-key cryptography for Internet telepathology.

    Science.gov (United States)

    Strauss, J S; Felten, C L; Okada, D H; Marchevsky, A M

    1999-01-01

    The Internet is a potentially inexpensive, widely available medium for telepathology, but there are concerns about its reliability and security. Using a digital camera, 41 photomicrographs of transbronchial biopsies, at x 100 optical magnification, were captured and digitized at 2700 x 3400 pixel, 24 bit/pixel resolution. The image files were saved in JPEG format at medium compression, attached to text files with patient information, encrypted for security in the S/MIME format using a digital signature and digital envelope, and transmitted by email. Received email files were decrypted automatically and the images viewed with standard software. Telepathology diagnoses were compared with original interpretations. The images averaged 810 kByte in size. The encryption and decryption did not cause significant delays in overall transmission time and, together with transmission, did not produce noticeable image degradation. The received image files could be viewed in a manner that simulated light microscopy. There was agreement between telepathology and original diagnoses in 92% of the cases. All the discrepancies were due to inadequate area selection because the pathological features of interest were present in histological levels other than those photographed. The use of high-resolution digital photomicrography, the Internet and public-key cryptography offers an effective and relatively inexpensive method of telepathology consultation. The method is best suited for the diagnosis of small biopsy specimens that require the transmission of only a few digital images that represent the majority of the biopsy materials.

  7. Security of Cooperative Intelligent Transport Systems: Standards, Threats Analysis and Cryptographic Countermeasures

    Directory of Open Access Journals (Sweden)

    Elyes Ben Hamida

    2015-07-01

    Full Text Available Due to the growing number of vehicles on the roads worldwide, road traffic accidents are currently recognized as a major public safety problem. In this context, connected vehicles are considered as the key enabling technology to improve road safety and to foster the emergence of next generation cooperative intelligent transport systems (ITS. Through the use of wireless communication technologies, the deployment of ITS will enable vehicles to autonomously communicate with other nearby vehicles and roadside infrastructures and will open the door for a wide range of novel road safety and driver assistive applications. However, connecting wireless-enabled vehicles to external entities can make ITS applications vulnerable to various security threats, thus impacting the safety of drivers. This article reviews the current research challenges and opportunities related to the development of secure and safe ITS applications. It first explores the architecture and main characteristics of ITS systems and surveys the key enabling standards and projects. Then, various ITS security threats are analyzed and classified, along with their corresponding cryptographic countermeasures. Finally, a detailed ITS safety application case study is analyzed and evaluated in light of the European ETSI TC ITS standard. An experimental test-bed is presented, and several elliptic curve digital signature algorithms (ECDSA are benchmarked for signing and verifying ITS safety messages. To conclude, lessons learned, open research challenges and opportunities are discussed.

  8. Ant-Crypto, a Cryptographer for Data Encryption Standard

    Directory of Open Access Journals (Sweden)

    Salabat Khan

    2013-01-01

    Full Text Available Swarm Intelligence and Evolutionary Techniques are attracting the cryptanalysts in the field of cryptography. This paper presents a novel swarm based attack called Ant-Crypto (Ant-Cryptographer for the cryptanalysis of Data Encryption Standard (DES. Ant-Crypto is based on Binary Ant Colony Optimization (BACO i.e. a binary search space based directed graph is modeled for efficiently searching the optimum result (an original encryption key, in our case. The reason that why evolutionary techniques are becoming attractive is because of the inapplicability of traditional techniques and brute force attacks against feistel ciphers due to their inherent structure based on high nonlinearity and low autocorrelation. Ant-Crypto uses a known-plaintext attack to recover the secret key of DES which is required to break/ decipher the secret messages. Ant-Crypto iteratively searches for the secret key while generating several candidate optimum keys that are guessed across different runs on the basis of routes completed by ants. These optimum keys are then used to find each individual bit of the 56 bit secret key used during encryption by DES. Ant-Crypto is compared with some other state of the art evolutionary based attacks i.e. Genetic Algorithm and Comprehensive Binary Particle Swarm Optimization. The experimental results show that Ant-Crypto is an effective evolutionary attack against DES and can deduce large number of valuable bits as compared to other evolutionary algorithms; both in terms of time and space complexity.

  9. An Efficient Cryptographic Hash Algorithm (BSA)

    CERN Document Server

    Mukherjee, Subhabrata; Laha, Anirban

    2012-01-01

    Recent cryptanalytic attacks have exposed the vulnerabilities of some widely used cryptographic hash functions like MD5 and SHA-1. Attacks in the line of differential attacks have been used to expose the weaknesses of several other hash functions like RIPEMD, HAVAL. In this paper we propose a new efficient hash algorithm that provides a near random hash output and overcomes some of the earlier weaknesses. Extensive simulations and comparisons with some existing hash functions have been done to prove the effectiveness of the BSA, which is an acronym for the name of the 3 authors.

  10. Disseminated Public-Key Management and Certificate Generation Scheme for MANET

    Directory of Open Access Journals (Sweden)

    Sanjay Kumar Chowlam

    2011-07-01

    Full Text Available In this paper, we first discuss the predominant assail abilities in the mobile ad hoc networks, which have made it much easier to prone to attacks than the traditional wired network. Then we discuss the basic operations of our public-key management scheme: creation of public (and private keys, issuing public-key certificates, storage of certificates, and key authentication by the nodes themselves without the control of any principal authority. More over the public key management scheme serves as an underlying mechanism for both key distribution and establishing security relationships between nodes.

  11. Bit-oriented quantum public-key encryption based on quantum perfect encryption

    Science.gov (United States)

    Wu, Chenmiao; Yang, Li

    2016-08-01

    A bit-oriented quantum public-key encryption scheme is presented. We use Boolean functions as private-key and randomly changed pairs of quantum state and classical string as public-keys. Following the concept of quantum perfect encryption, we prepare the public-key with Hadamard transformation and Pauli transformation. The quantum part of public-keys is various with different classical strings. In contrast to the typical classical public-key scheme, one private-key in our scheme corresponds to an exponential number of public-keys. We investigate attack to the private-key and prove that the public-key is a totally mixed state. So the adversary cannot acquire any information about private-key from measurement of the public-key. Then, the attack to encryption is analyzed. Since the trace distance between two different ciphertexts is zero, the adversary cannot distinguish between the two ciphertext states and also obtains nothing about plaintext and private-key. Thus, we have the conclusion that the proposed scheme is information-theoretically secure under an attack of the private-key and encryption.

  12. Cryptographic Combinatorial Clock-Proxy Auctions

    Science.gov (United States)

    Parkes, David C.; Rabin, Michael O.; Thorpe, Christopher

    We present a cryptographic protocol for conducting efficient, provably correct and secrecy-preserving combinatorial clock-proxy auctions. The “clock phase” functions as a trusted auction despite price discovery: bidders submit encrypted bids, and prove for themselves that they meet activity rules, and can compute total demand and thus verify price increases without revealing any information about individual demands. In the sealed-bid “proxy phase”, all bids are revealed the auctioneer via time-lapse cryptography and a branch-and-bound algorithm is used to solve the winner-determination problem. Homomorphic encryption is used to prove the correctness of the solution, and establishes the correctness of the solution to any interested party. Still an NP-hard optimization problem, the use of homomorphic encryption imposes additional computational time on winner-determination that is linear in the size of the branch-and-bound search tree, and thus roughly linear in the original (search-based) computational time. The result is a solution that avoids, in the usual case, the exponential complexity of previous cryptographically-secure combinatorial auctions.

  13. SD-REE: A Cryptographic Method to Exclude Repetition from a Message

    CERN Document Server

    Dey, Somdip

    2012-01-01

    In this paper, the author presents a new cryptographic technique, SD-REE, to exclude the repetitive terms in a message, when it is to be encrypted, so that it becomes almost impossible for a person to retrieve or predict the original message from the encrypted message. In modern world, cryptography hackers try to break a code or cryptographic algorithm [1,2] or retrieve the key, used for encryption, by inserting repetitive bytes / characters in the message and encrypt the message or by analyzing repetitions in the encrypted message, to find out the encryption algorithm or retrieve the key used for the encryption. But in SD-REE method the repetitive bytes / characters are removed and there is no trace of any repetition in the message, which was encrypted.

  14. Argumentation Key to Communicating Climate Change to the Public

    Science.gov (United States)

    Bleicher, R. E.; Lambert, J. L.

    2012-12-01

    Argumentation plays an important role in how we communicate climate change science to the public and is a key component integrated throughout the Next Generation Science Standards. A scientific argument can be described as a disagreement between explanations with data being used to justify each position. Argumentation is social process where two or more individuals construct and critique arguments (Kuhn & Udell, 2003; Nussbaum, 1997). Sampson, Grooms, and Walker's (2011) developed a framework for understanding the components of a scientific argument. The three components start with a claim (a conjecture, conclusion, explanation, or an answer to a research question). This claim must fit the evidence (observations that show trends over time, relationships between variables or difference between groups). The evidence must be justified with reasoning (explains how the evidence supports the explanation and whey it should count as support). In a scientific argument, or debate, the controversy focuses on how data were collected, what data can or should be included, and what inferences can be made based on a set of evidence. Toulmin's model (1969) also includes rebutting or presenting an alternative explanation supported by counter evidence and reasoning of why the alternative is not the appropriate explanation for the question of the problem. The process of scientific argumentation should involve the construction and critique of scientific arguments, one that involves the consideration of alternative hypotheses (Lawson, 2003). Scientific literacy depends as much on the ability to refute and recognize poor scientific arguments as much as it does on the ability to present an effective argument based on good scientific data (Osborne, 2010). Argument is, therefore, a core feature of science. When students learn to construct a sound scientific argument, they demonstrate critical thinking and a mastery of the science being taught. To present a convincing argument in support of

  15. Public engagement with CCS: barriers, key issues and ways forward

    Science.gov (United States)

    Xenias, Dimitrios

    2017-04-01

    Although Carbon Capture and Storage (CCS) is recognised as a crucial transition technology to a low-carbon world, it has not been popular with the public or some governments (e.g. the UK). Also, despite its use in industrial processes for decades, CCS remains and unfamiliar technology for most publics. It is therefore important to foster top-down and bottom-up acceptance of large scale CCS. In an exploratory round of interviews we canvassed the views of British, Dutch, German and Norwegian experts (N=13) with previous experience in public engagement with CCS. They identified barriers and drivers for CCS deployment and public engagement with CCS. Thematic analysis revealed a small number of recurrent issues, including: (a) lack of political leadership on CCS; (b) lack of public knowledge on relevant technologies and (c) difficulty communicating why CCS is necessary. Emphasis on these barriers varied with the level of experts' engagement with the public. More interestingly, although most experts agreed on the importance of public engagement, their views divided between 'why' engage and 'how' best to do this. In a subsequent expert survey (N=99) interview findings were reinforced: public support was seen as important for CCS roll-out (72%), though lower than political support and funding. The survey also showed that local public was expected to experience most risks, while global public will experience most benefits; whereas local business is seen to benefit more than global. Experts were overwhelmingly positive about CCS - risks outweigh benefits, and are confident that CCS will play a major role in climate change mitigation (along with reduced energy demand and renewables). These findings will be expanded on and triangulated in a follow-up public survey which will benefit those involved with public engagement with CCS.

  16. A brief review of revocable ID-based public key cryptosystem

    Directory of Open Access Journals (Sweden)

    Tsu-Yang Wu

    2016-03-01

    Full Text Available The design of ID-based cryptography has received much attention from researchers. However, how to revoke the misbehaviour/compromised user in ID-based public key cryptosystem becomes an important research issue. Recently, Tseng and Tsai proposed a novel public key cryptosystem called revocable ID-based public key cryptosystem (RIBE to solve the revocation problem. Later on, numerous research papers based on the Tseng-Tsai key RIBE were proposed. In this paper, we brief review Tseng and Tsai's RIBE. We hope this review can help the readers to understand the Tseng and Tsai's revocable ID-based public key cryptosystem.

  17. Protecting Cryptographic Keys and Functions from Malware Attacks

    Science.gov (United States)

    2010-12-01

    and values in each of various stages in the scrambling process. The possible attack routes are explained in Section 2.4 and analyzed in Section 2.5...February 2011, pp 28-43). 4. X. Li, P. Parker, and S. Xu. A Probabilistic Characterization of A Fault-Tolerant Gossiping Algorithm. Journal of Systems...4856, pp. 228-246, Springer, 2007. 7. Xiaohu Li, T. Paul Parker, and Shouhuai Xu. A Stochastic Characterization of a Fault-Tolerant Gossip Algorithm

  18. Cryptographic keys from noisy data, theory and applications

    NARCIS (Netherlands)

    Buhan, I.R.

    2008-01-01

    Biometric security systems that verify a person's identity by scanning fingers, hands, eye or face are becoming more and more common. As a result biometrics is one of the fastest growing industries. Applications for biometrics range from homeland security physical access to various facilities and

  19. Cryptographic keys from noisy data, theory and applications

    NARCIS (Netherlands)

    Buhan, Ileana Rozalia

    2008-01-01

    Biometric security systems that verify a person's identity by scanning fingers, hands, eye or face are becoming more and more common. As a result biometrics is one of the fastest growing industries. Applications for biometrics range from homeland security physical access to various facilities and he

  20. Physical cryptographic verification of nuclear warheads

    Science.gov (United States)

    Kemp, R. Scott; Danagoulian, Areg; Macdonald, Ruaridh R.; Vavrek, Jayson R.

    2016-08-01

    How does one prove a claim about a highly sensitive object such as a nuclear weapon without revealing information about the object? This paradox has challenged nuclear arms control for more than five decades. We present a mechanism in the form of an interactive proof system that can validate the structure and composition of an object, such as a nuclear warhead, to arbitrary precision without revealing either its structure or composition. We introduce a tomographic method that simultaneously resolves both the geometric and isotopic makeup of an object. We also introduce a method of protecting information using a provably secure cryptographic hash that does not rely on electronics or software. These techniques, when combined with a suitable protocol, constitute an interactive proof system that could reject hoax items and clear authentic warheads with excellent sensitivity in reasonably short measurement times.

  1. Quantum Communication Attacks on Classical Cryptographic Protocols

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre

    , one can show that the protocol remains secure even under such an attack. However, there are also cases where the honest players are quantum as well, even if the protocol uses classical communication. For instance, this is the case when classical multiparty computation is used as a “subroutine......” in quantum multiparty computation. Furthermore, in the future, players in a protocol may employ quantum computing simply to improve efficiency of their local computation, even if the communication is supposed to be classical. In such cases, it no longer seems clear that a quantum adversary must be limited......In the literature on cryptographic protocols, it has been studied several times what happens if a classical protocol is attacked by a quantum adversary. Usually, this is taken to mean that the adversary runs a quantum algorithm, but communicates classically with the honest players. In several cases...

  2. Cryptographic Protocols Based on Root Extracting

    DEFF Research Database (Denmark)

    Koprowski, Maciej

    In this thesis we design new cryptographic protocols, whose security is based on the hardness of root extracting or more speci cally the RSA problem. First we study the problem of root extraction in nite Abelian groups, where the group order is unknown. This is a natural generalization of the...... construction based on root extracting. As an example of this, we modify Cramer-Shoup signature scheme such that it becomes a genericm algorithm. We discuss then implementing it in RSA groups without the original restriction that the modulus must be a product of safe primes. It can also be implemented in class......,  providing a currently acceptable level of security. This allows us to propose the rst practical blind signature scheme provably secure, without relying on heuristics called random oracle model (ROM). We obtain the protocol for issuing blind signatures by implementing our modi ed Fischlin's signing algorithm...

  3. A New Proxy Signature Scheme with Message Recovery Using Self-Certified Public Key

    Institute of Scientific and Technical Information of China (English)

    LI Ji-guo; ZHANG Yi-chen; ZHU Yue-long

    2005-01-01

    A proxy signature scheme with message recovery using self-certified public key is proposed, which withstands public key substitution attacks, active attacks, and forgery attacks. The proposed scheme accomplishes the tasks of public key verification, proxy signature verification, and message recovery in a logically single step. In addition, the proposed scheme satisfies all properties of strong proxy signature and does not use secure channel in the communication between the original signer and the proxy signature signer.

  4. Information verification cryptosystem using one-time keys based on double random phase encoding and public-key cryptography

    Science.gov (United States)

    Zhao, Tieyu; Ran, Qiwen; Yuan, Lin; Chi, Yingying; Ma, Jing

    2016-08-01

    A novel image encryption system based on double random phase encoding (DRPE) and RSA public-key algorithm is proposed. The main characteristic of the system is that each encryption process produces a new decryption key (even for the same plaintext), thus the encryption system conforms to the feature of the one-time pad (OTP) cryptography. The other characteristic of the system is the use of fingerprint key. Only with the rightful authorization will the true decryption be obtained, otherwise the decryption will result in noisy images. So the proposed system can be used to determine whether the ciphertext is falsified by attackers. In addition, the system conforms to the basic agreement of asymmetric cryptosystem (ACS) due to the combination with the RSA public-key algorithm. The simulation results show that the encryption scheme has high robustness against the existing attacks.

  5. Evaluation of Information Leakage from Cryptographic Hardware via Common-Mode Current

    Science.gov (United States)

    Hayashi, Yu-Ichi; Homma, Naofumi; Mizuki, Takaaki; Sugawara, Takeshi; Kayano, Yoshiki; Aoki, Takafumi; Minegishi, Shigeki; Satoh, Akashi; Sone, Hideaki; Inoue, Hiroshi

    This paper presents a possibility of Electromagnetic (EM) analysis against cryptographic modules outside their security boundaries. The mechanism behind the information leakage is explained from the view point of Electromagnetic Compatibility: electric fluctuation released from cryptographic modules can conduct to peripheral circuits based on ground bounce, resulting in radiation. We demonstrate the consequence of the mechanism through experiments where the ISO/IEC standard block cipher AES (Advanced Encryption Standard) is implemented on an FPGA board and EM radiations from power and communication cables are measured. Correlation Electromagnetic Analysis (CEMA) is conducted in order to evaluate the information leakage. The experimental results show that secret keys are revealed even though there are various disturbing factors such as voltage regulators and AC/DC converters between the target module and the measurement points. We also discuss information-suppression techniques as electrical-level countermeasures against such CEMAs.

  6. Cryptographic applications of analytic number theory complexity lower bounds and pseudorandomness

    CERN Document Server

    2003-01-01

    The book introduces new ways of using analytic number theory in cryptography and related areas, such as complexity theory and pseudorandom number generation. Key topics and features: - various lower bounds on the complexity of some number theoretic and cryptographic problems, associated with classical schemes such as RSA, Diffie-Hellman, DSA as well as with relatively new schemes like XTR and NTRU - a series of very recent results about certain important characteristics (period, distribution, linear complexity) of several commonly used pseudorandom number generators, such as the RSA generator, Blum-Blum-Shub generator, Naor-Reingold generator, inversive generator, and others - one of the principal tools is bounds of exponential sums, which are combined with other number theoretic methods such as lattice reduction and sieving - a number of open problems of different level of difficulty and proposals for further research - an extensive and up-to-date bibliography Cryptographers and number theorists will find th...

  7. Key Performance Indicators of Public Universities Based on Quality Assessment Criteria in Thailand

    Science.gov (United States)

    Sukboonyasatit, Kritsana; Thanapaisarn, Chaiwit; Manmar, Lampang

    2011-01-01

    The research objective was to develop public universities' key performance indicators. Qualitative research and interviews were employed with each public university's senior executive and quality assessors. The sample group was selected by the office of the public sector development commission and Thailand's public universities can be separated…

  8. Public Participation: Do's and Don't's & Key Messages

    NARCIS (Netherlands)

    Astley, T.; Massey, H.

    2005-01-01

    This document has been produced to provide a tool to project managers to enable them to quickly assess whether or not participation is the right thing to do and the key Dos and Donts of participation. An example of a Community Engagement Plan in the UK is discribed.

  9. Research of the Kernel Operator Library Based on Cryptographic Algorithm

    Institute of Scientific and Technical Information of China (English)

    王以刚; 钱力; 黄素梅

    2001-01-01

    The variety of encryption mechanism and algorithms which were conventionally used have some limitations.The kernel operator library based on Cryptographic algorithm is put forward. Owing to the impenetrability of algorithm, the data transfer system with the cryptographic algorithm library has many remarkable advantages in algorithm rebuilding and optimization,easily adding and deleting algorithm, and improving the security power over the traditional algorithm. The user can choose any one in all algorithms with the method against any attack because the cryptographic algorithm library is extensible.

  10. Writing for Professional Publication. Keys to Academic and Business Success.

    Science.gov (United States)

    Henson, Kenneth T.

    This book provides practical help for people writing for publication, especially for those writing for professional journals or university presses. Chapters cover the following topics: (1) reasons for writing; (2) finding topics; (3) getting started; (4) writing style; (5) organizing articles; (6) using journals, libraries, surveys, and action…

  11. About the Key Escrow Properties of Identity Based Encryption Schemes

    Directory of Open Access Journals (Sweden)

    Ruxandra Olimid

    2012-09-01

    Full Text Available IBE (Identity Based Encryption represents a type of public key encryption that allows a party to encrypt a message using the recipient’s identity as public key. The private keys needed for decryption are generated and distributed to each party by a KGC (Key Generation Center. The existence of such an entity in an IBE scheme allows access to the encrypted information for other parties other than the intended recipient by construction: the KGC or any other entity that receives the cryptographic keys from the KGC may perform decryption. A system that permits other parties to have access to the private keys of the users is said to have key escrow abilities. The paper performs a brief analysis of the key escrow properties of IBE schemes and gives a practical example of communication protocol that improves the key escrow capabilities.

  12. 一种基于PKI的密钥%An Internet Key Exchange Protocol Based on Public Key Infrastructure

    Institute of Scientific and Technical Information of China (English)

    朱建明; 马建峰

    2004-01-01

    Internet key exchange (IKE) is an automated key exchange mechanism that is used to facilitate the transfer of IPSec security associations (SAs).Public key infrastructure (PKI) is considered as a key element for providing security to new distributed communication networks and services.In this paper, we concentrate on the properties of the protocol of Phase 1 IKE.After investigating IKE protocol and PKI technology, we combine IKE protocol and PKI and present an implementation scheme of the IKE based on PKI.Then, we give a logic analysis of the proposed protocol with the BAN-logic and discuss the security of the protocol.The result indicates that the protocol is correct and satisfies the security requirements of Internet key exchange.

  13. Physically unclonable cryptographic primitives using self-assembled carbon nanotubes

    Science.gov (United States)

    Hu, Zhaoying; Comeras, Jose Miguel M. Lobez; Park, Hongsik; Tang, Jianshi; Afzali, Ali; Tulevski, George S.; Hannon, James B.; Liehr, Michael; Han, Shu-Jen

    2016-06-01

    Information security underpins many aspects of modern society. However, silicon chips are vulnerable to hazards such as counterfeiting, tampering and information leakage through side-channel attacks (for example, by measuring power consumption, timing or electromagnetic radiation). Single-walled carbon nanotubes are a potential replacement for silicon as the channel material of transistors due to their superb electrical properties and intrinsic ultrathin body, but problems such as limited semiconducting purity and non-ideal assembly still need to be addressed before they can deliver high-performance electronics. Here, we show that by using these inherent imperfections, an unclonable electronic random structure can be constructed at low cost from carbon nanotubes. The nanotubes are self-assembled into patterned HfO2 trenches using ion-exchange chemistry, and the width of the trench is optimized to maximize the randomness of the nanotube placement. With this approach, two-dimensional (2D) random bit arrays are created that can offer ternary-bit architecture by determining the connection yield and switching type of the nanotube devices. As a result, our cryptographic keys provide a significantly higher level of security than conventional binary-bit architecture with the same key size.

  14. Quantum cryptography using coherent states: Randomized encryption and key generation

    Science.gov (United States)

    Corndorf, Eric

    With the advent of the global optical-telecommunications infrastructure, an increasing number of individuals, companies, and agencies communicate information with one another over public networks or physically-insecure private networks. While the majority of the traffic flowing through these networks requires little or no assurance of secrecy, the same cannot be said for certain communications between banks, between government agencies, within the military, and between corporations. In these arenas, the need to specify some level of secrecy in communications is a high priority. While the current approaches to securing sensitive information (namely the public-key-cryptography infrastructure and deterministic private-key ciphers like AES and 3DES) seem to be cryptographically strong based on empirical evidence, there exist no mathematical proofs of secrecy for any widely deployed cryptosystem. As an example, the ubiquitous public-key cryptosystems infer all of their secrecy from the assumption that factoring of the product of two large primes is necessarily time consuming---something which has not, and perhaps cannot, be proven. Since the 1980s, the possibility of using quantum-mechanical features of light as a physical mechanism for satisfying particular cryptographic objectives has been explored. This research has been fueled by the hopes that cryptosystems based on quantum systems may provide provable levels of secrecy which are at least as valid as quantum mechanics itself. Unfortunately, the most widely considered quantum-cryptographic protocols (BB84 and the Ekert protocol) have serious implementation problems. Specifically, they require quantum-mechanical states which are not readily available, and they rely on unproven relations between intrusion-level detection and the information available to an attacker. As a result, the secrecy level provided by these experimental implementations is entirely unspecified. In an effort to provably satisfy the cryptographic

  15. Cryptographic Trust Management Requirements Specification: Version 1.1

    Energy Technology Data Exchange (ETDEWEB)

    Edgar, Thomas W.

    2009-09-30

    The Cryptographic Trust Management (CTM) Project is being developed for Department of Energy, OE-10 by the Pacific Northwest National Laboratory (PNNL). It is a component project of the NSTB Control Systems Security R&D Program.

  16. Cryptographic Technique Used Lower and Upper Triangular Decomposition Method

    Directory of Open Access Journals (Sweden)

    B. KumaraswamyAchary,

    2016-02-01

    Full Text Available In this paper, the main cryptographic technique we will use affine cipher used for encryption and also decryption by using one of the linear algebra technique lower and upper triangular technique

  17. Key elements for a measurement framework for public sector innovation

    DEFF Research Database (Denmark)

    Bloch, Carter Walter; Lopez-Bassols, Vladimir

    2013-01-01

    This document provides an overview of recent NESTI work on developing guidelines for measuring public sector innovation (PSI). The paper includes an update on various ongoing activities which will contribute to the development of a measurement framework for PSI and outlines a number of areas which...... could be further addressed in a final report. Delegates are invited to discuss the proposals and provide inputs on the next steps of the work, particularly regarding the use of multiple approaches, the scope of the measurement framework, the need for core definitions,and priorities for indicators...

  18. Public Key Encryption Supporting Plaintext Equality Test and User-Specified Authorization

    NARCIS (Netherlands)

    Tang, Qiang

    2011-01-01

    In this paper we investigate a category of public key encryption schemes which supports plaintext equality test and user-specified authorization. With this new primitive, two users, who possess their own public/private key pairs, can issue token(s) to a proxy to authorize it to perform plaintext

  19. Public key encryption supporting plaintext equality test and user-specified authorization

    NARCIS (Netherlands)

    Tang, Qiang

    2012-01-01

    In this paper, we investigate a category of public key encryption schemes that supports plaintext equality test and userspecified authorization. With this new primitive, two users, who possess their own public/private key pairs, can issue token(s) to a proxy to authorize it to perform plaintext

  20. Attack on and Improvement of the Running Mode of the Two-Party Cryptographic Protocols%对两个双方密码协议运行模式的攻击及改进

    Institute of Scientific and Technical Information of China (English)

    姬东耀; 冯登国

    2003-01-01

    In this paper,the running modes of the two-party cryptographic protocols are used to analyze the two authentication and key agreenment protocols,and attack on the protocols is discovered. Finally,two improved protocols are given.

  1. Sustainability as the key to prioritize investments in public infrastructures

    Energy Technology Data Exchange (ETDEWEB)

    Pardo-Bosch, Francesc, E-mail: francesc.pardo@upc.edu [Departament d' Enginyeria Civil i Ambiental, Universitat Politècnica de Catalunya - Barcelona Tech. (Spain); Political Science Department, University of California - Berkeley (United States); Aguado, Antonio, E-mail: antonio.aguado@upc.edu [Departament d' Enginyeria Civil i Ambiental, Universitat Politècnica de Catalunya - Barcelona Tech. (Spain)

    2016-09-15

    Infrastructure construction, one of the biggest driving forces of the economy nowadays, requires a huge analysis and clear transparency to decide what projects have to be executed with the few resources available. With the aim to provide the public administrations a tool with which they can make their decisions easier, the Sustainability Index of Infrastructure Projects (SIIP) has been defined, with a multi-criteria decision system called MIVES, in order to classify non-uniform investments. This index evaluates, in two inseparable stages, the contribution to the sustainable development of each infrastructure project, analyzing its social, environmental and economic impact. The result of the SIIP allows to decide the order with which projects will be prioritized. The case of study developed proves the adaptability and utility of this tool for the ordinary budget management.

  2. Cryptographic protocol security analysis based on bounded constructing algorithm

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    An efficient approach to analyzing cryptographic protocols is to develop automatic analysis tools based on formal methods. However, the approach has encountered the high computational complexity problem due to reasons that participants of protocols are arbitrary, their message structures are complex and their executions are concurrent. We propose an efficient automatic verifying algorithm for analyzing cryptographic protocols based on the Cryptographic Protocol Algebra (CPA) model proposed recently, in which algebraic techniques are used to simplify the description of cryptographic protocols and their executions. Redundant states generated in the analysis processes are much reduced by introducing a new algebraic technique called Universal Polynomial Equation and the algorithm can be used to verify the correctness of protocols in the infinite states space. We have implemented an efficient automatic analysis tool for cryptographic protocols, called ACT-SPA, based on this algorithm, and used the tool to check more than 20 cryptographic protocols. The analysis results show that this tool is more efficient, and an attack instance not offered previously is checked by using this tool.

  3. Using Animation in Active Learning Tool to Detect Possible Attacks in Cryptographic Protocols

    Science.gov (United States)

    Ali Mayouf, Mabroka; Shukur, Zarina

    Interactive Visualization tools for active learning of generic cryptographic protocols are very few. Although these tools provide the possibility to engage the learner by asking him to describe a cryptographic protocol using a simple visual metaphor to represent the abstraction of the concepts being visualized, the problem is that some cryptographic operations are not visualized or animated and hidden from the learner's perspective such as encryption/decryption actions. Other operations are not supported by these tools such as timestamp and freshness. So, it's difficult to cover all possible attack that the intruder might employ with such operations are missing. The purpose of this research is to provide an interactive visualization tool for teaching undergraduate students security protocols concepts especially key distribution, multiple operations such as encryption/decryption and signed/unsigned operations, and possible protocol attacks. By designing a high quality graphical user interface and simple visual metaphor, learners will be able to specify the protocols and consider the possible attack at each step of protocol demonstration.

  4. Universal Keyword Classifier on Public Key Based Encrypted Multikeyword Fuzzy Search in Public Cloud.

    Science.gov (United States)

    Munisamy, Shyamala Devi; Chokkalingam, Arun

    2015-01-01

    Cloud computing has pioneered the emerging world by manifesting itself as a service through internet and facilitates third party infrastructure and applications. While customers have no visibility on how their data is stored on service provider's premises, it offers greater benefits in lowering infrastructure costs and delivering more flexibility and simplicity in managing private data. The opportunity to use cloud services on pay-per-use basis provides comfort for private data owners in managing costs and data. With the pervasive usage of internet, the focus has now shifted towards effective data utilization on the cloud without compromising security concerns. In the pursuit of increasing data utilization on public cloud storage, the key is to make effective data access through several fuzzy searching techniques. In this paper, we have discussed the existing fuzzy searching techniques and focused on reducing the searching time on the cloud storage server for effective data utilization. Our proposed Asymmetric Classifier Multikeyword Fuzzy Search method provides classifier search server that creates universal keyword classifier for the multiple keyword request which greatly reduces the searching time by learning the search path pattern for all the keywords in the fuzzy keyword set. The objective of using BTree fuzzy searchable index is to resolve typos and representation inconsistencies and also to facilitate effective data utilization.

  5. Universal Keyword Classifier on Public Key Based Encrypted Multikeyword Fuzzy Search in Public Cloud

    Directory of Open Access Journals (Sweden)

    Shyamala Devi Munisamy

    2015-01-01

    Full Text Available Cloud computing has pioneered the emerging world by manifesting itself as a service through internet and facilitates third party infrastructure and applications. While customers have no visibility on how their data is stored on service provider’s premises, it offers greater benefits in lowering infrastructure costs and delivering more flexibility and simplicity in managing private data. The opportunity to use cloud services on pay-per-use basis provides comfort for private data owners in managing costs and data. With the pervasive usage of internet, the focus has now shifted towards effective data utilization on the cloud without compromising security concerns. In the pursuit of increasing data utilization on public cloud storage, the key is to make effective data access through several fuzzy searching techniques. In this paper, we have discussed the existing fuzzy searching techniques and focused on reducing the searching time on the cloud storage server for effective data utilization. Our proposed Asymmetric Classifier Multikeyword Fuzzy Search method provides classifier search server that creates universal keyword classifier for the multiple keyword request which greatly reduces the searching time by learning the search path pattern for all the keywords in the fuzzy keyword set. The objective of using BTree fuzzy searchable index is to resolve typos and representation inconsistencies and also to facilitate effective data utilization.

  6. A Novel Visual Cryptographic Method for Color Images

    Directory of Open Access Journals (Sweden)

    Amarjot Singh

    2013-05-01

    Full Text Available Visual cryptography is considered to be a vital technique for hiding visual data from intruders. Because of its importance, it finds applications in various sectors such as E-voting system, financial documents and copyright protections etc. A number of methods have been proposed in past for encrypting color images such as color decomposition, contrast manipulation, polynomial method, using the difference in color intensity values in a color image etc. The major flaws with most of the earlier proposed methods is the complexity encountered during the implementation of the methods on a wide scale basis, the problem of random pixilation and insertion of noise in encrypted images. This paper presents a simple and highly resistant algorithm for visual cryptography to be performed on color images. The main advantage of the proposed cryptographic algorithm is the robustness and low computational cost with structure simplicity. The proposed algorithm outperformed the conventional methods when tested over sample images proven using key analysis, SSIM and histogram analysis tests. In addition, the proposed method overshadows the standard method in terms of the signal to noise ratio obtained for the encrypted image, which is much better than the SNR value obtained using the standard method. The paper also makes a worst case analysis for the SNR values for both the methods.

  7. Breaking the HFEM public key scheme%破解HFEM公钥密码方案

    Institute of Scientific and Technical Information of China (English)

    古春生

    2013-01-01

    To design post-quantum public key cryptography, Zhao, et al presented a novel public key scheme based on the BMQ problem. An equivalent secret key could directly be solved from the public key of their scheme by applying the property of the ergodic matrix over finite field. Thus, the HFEM public key scheme was broken.%  为设计后量子公钥密码,赵永哲等人提出了一种基于BMQ问题新的公钥方案。利用有限域上遍历矩阵的性质,从该方案公钥能够直接求出其等价私钥,从而破解了该HFEM公钥密码方案。

  8. Fast public-key encryption scheme based on Chinese remainder theorem

    Institute of Scientific and Technical Information of China (English)

    Baocang WANG; Yongzhuang WEI; Yupu HU

    2009-01-01

    Traditional public-key cryptosystems suffer from a relatively low encryption/decryption speed, which hampers their applications in resource-constrained environments. A fast public-key cryptosystem is proposed to remedy this drawback. The new algorithm uses Chinese remainder theorem to hide the trapdoor information. The encryption of the system only carries out several modular multiplication operations, and the decryption only needs a modular multiplication and a low-dimensional matrixvector multiplication, which makes the speed of the encryption and the decryption of the scheme very high.The security of the system is based on two difficult number-theoretic problems. The attacker has to solve the integer factorization problem and the simultaneous Diophantine approximation problem simultaneously to recover the secret key from the public key. The proposed cryptosystem is also shown to be secure against lattice attack. The analysis shows that the encryption algorithm is a secure, fast and efficient public-key cryptosystem.

  9. Measuring Public Leadership: Developing Scales for Four Key Public Leadership Roles

    NARCIS (Netherlands)

    Tummers, Lars; Knies, Eva|info:eu-repo/dai/nl/313875421

    2016-01-01

    This article on public leadership contributes to the literature by (1) focusing on the ‘public’ aspect of leadership and (2) developing quantitative scales for measuring four public leadership roles. These roles all refer to the extent to which public leaders actively support their employees in

  10. Measuring Public Leadership: Developing Scales for Four Key Public Leadership Roles

    NARCIS (Netherlands)

    Tummers, Lars; Knies, Eva

    2016-01-01

    This article on public leadership contributes to the literature by (1) focusing on the ‘public’ aspect of leadership and (2) developing quantitative scales for measuring four public leadership roles. These roles all refer to the extent to which public leaders actively support their employees in deal

  11. Data publication and dissemination of interactive keys under the open access model

    Directory of Open Access Journals (Sweden)

    Lyubomir Penev

    2009-09-01

    Full Text Available The concepts of publication, citation and dissemination of interactive keys and other online keys are discussed and illustrated by a sample paper published in the present issue (doi: 10.3897/zookeys.21.271. The present model is based on previous experience with several existing examples of publishing online keys. However, this model also suggests ways to publish, cite, preserve, disseminate and reuse the original data files to the benefit of the authors, future workers, and society in general. To be regarded as a ''formal scientific publication,'' an online key should satisfy the same criteria of peer review, registration, persistence, bibliographic description, etc., as conventional publications. Keys can be published in a form of either ''static'\\''dynamic'' publications. We define a ''static'' publication as a discrete unit of information preserved in a persistent and unchangeable way on the publisher’s Web site and/or on paper and consequently in conventional/electronic libraries and archives. This contrasts with the nature of the Internet, which allows and tends to encourage updating and improvement on a continuing basis. We call ''dynamic'' a publication of an interactive key on a Web site where its contents can be continuously updated. ''Dynamic'' publications meet some of the criteria of a ''formal scientific publication'' (identification, citation and location, while they lack other important features of it (persistence, archiving, indexing, science metric and citation metric services. Dynamic Web-based interactive keys may benefit from publishing the first version of their underlying datasets in a form of “formal scientific publication”. We define here the minimum set of data files to be published for several different platforms (Intkey, Lucid2, Lucid3, MX to ensure both (1 priority, identification, location and citation of the firstly published work and (2 future use and re-use of the keys.

  12. Trust Threshold Based Public Key Management in Mobile Ad Hoc Networks

    Science.gov (United States)

    2016-03-05

    used trust mechanism. Many studies used certificate-based public key manage- ent. However, they have brought out practical limitations cluding high...certificate-based public key management hemes cited above expose practical limitations, including eeding a centralized trusted CA [25] , high...ent sociability derived from the trust profile availabl a priori as well as dynamic social behavior measure by the number of nodes that a node

  13. A new spin on quantum cryptography: Avoiding trapdoors and embracing public keys

    CERN Document Server

    Ioannou, Lawrence M

    2011-01-01

    We give new arguments in support of \\emph{signed quantum key establishment}, where quantum cryptography is used in a public-key infrastructure that provides the required authentication. We also analyze more thoroughly than previous works the benefits that quantum key establishment protocols have over certain classical protocols, motivated in part by the various objections to quantum key establishment that are sometimes raised. Previous knowledge of quantum cryptography on the reader's part is not required for this article, as the definition of "quantum key establishment" that we use is an entirely classical and black-box characterization (one need only trust that protocols satisfying the definition exist).

  14. Security of public key encryption technique based on multiple chaotic systems

    Energy Technology Data Exchange (ETDEWEB)

    Wang Kai [Department of Radio Engineering, Southeast University, Nanjing 210096 (China)]. E-mail: kaiwang@seu.edu.cn; Pei Wenjiang [Department of Radio Engineering, Southeast University, Nanjing 210096 (China); Zou Liuhua [Department of Radio Engineering, Southeast University, Nanjing 210096 (China); Cheung Yiuming [Department of Computer Science, Hong Kong Baptist University, Hong Kong (China); He Zhenya [Department of Radio Engineering, Southeast University, Nanjing 210096 (China)

    2006-12-25

    Recently, a new public key encryption technique based on multiple chaotic systems has been proposed [B. Ranjan, Phys. Rev. Lett. 95 (2005) 098702]. This scheme employs m-chaotic systems and a set of linear functions for key exchange over an insecure channel. Security of the proposed algorithm grows as (NP){sup m}, where N, P are the size of the key and the computational complexity of the linear functions respectively. In this Letter, the fundamental weakness of the cryptosystem is pointed out and a successful attack is described. Given the public keys and the initial vector, one can calculate the secret key based on Parseval's theorem. Both theoretical and experimental results show that the attacker can access to the secret key without difficulty. The lack of security discourages the use of such algorithm for practical applications.

  15. Data publication and dissemination of interactive keys under the open access model

    Science.gov (United States)

    The concepts of publication, citation and dissemination of interactive keys and other online keys are discussed and illustrated by a sample paper published in the present issue (doi: 10.3897/zookeys.21.271). The present model is based on previous experience with several existing examples of publishi...

  16. Health on Course? Key Messages from the 2002 Dutch Public Health Status and Forecasts Report

    NARCIS (Netherlands)

    Oers JAM van; VTV

    2003-01-01

    The third Dutch Public Health Status and Forecasts (PHSF) report once again contains a large amount of up-todate information about Dutch public health status, prevention and healthcare and includes international and regional comparisons. This brochure contains the Key Messages of the 2002 PHSF summa

  17. A New Approach in Cryptographic Systems Using Fractal Image Coding

    Directory of Open Access Journals (Sweden)

    Nadia M.G. Al-Saidi

    2009-01-01

    Full Text Available Problem statement: With the rapid development in the communications and information transmissions there is a growing demand for new approaches that increase the security of cryptographic systems. Approach: Therefore some emerging theories, such as fractals, can be adopted to provide a contribution toward this goal. In this study we proposed a new cryptographic system utilizing fractal theories; this approach exploited the main feature of fractals generated by IFS techniques. Results: Double enciphering and double deciphering methods performed to enhance the security of the system. The encrypted date represented the attractor generated by the IFS transformation, collage theorem was used to find the IFSM for decrypting data. Conclusion/Recommendations: The proposed method gave the possibility to hide maximum amount of data in an image that represent the attractor of the IFS without degrading its quality and to make the hidden data robust enough to withstand known cryptographic attacks and image processing techniques which did not change the appearance of image.

  18. Limits on the Power of Cryptographic Cheap Talk

    DEFF Research Database (Denmark)

    Hubacek, Pavel; Nielsen, Jesper Buus; Rosen, Alon

    2013-01-01

    We revisit the question of whether cryptographic protocols can replace correlated equilibria mediators in two-player strategic games. This problem was first addressed by Dodis, Halevi and Rabin (CRYPTO 2000), who suggested replacing the mediator with a secure protocol and proved that their solution...... is stable in the Nash equilibrium (NE) sense, provided that the players are computationally bounded. We show that there exist two-player games for which no cryptographic protocol can implement the mediator in a sequentially rational way; that is, without introducing empty threats. This explains why all...... and sufficient cryptographic assumptions for implementing a mediator that allows to achieve a given utility profile of a correlated equilibrium. The picture that emerges is somewhat different than the one arising in semi-honest secure two-party computation. Specifically, while in the latter case every...

  19. A Public Key Encryption Scheme Based on the Polynomial Reconstruction Problem

    OpenAIRE

    Augot, Daniel; Finiasz, Matthieu

    2003-01-01

    International audience; The Polynomial Reconstruction problem (PR) has been introduced in 1999 as a new hard problem. Several cryptographic primitives established on this problem have been constructed, for instance Naor and Pinkas have proposed a protocol for oblivious polynomial evaluation. Then it has been studied from the point of view of robustness, and several important properties have been discovered and proved by Kiayias and Yung. Furthermore the same authors constructed a symmetric ci...

  20. Feasibility and Completeness of Cryptographic Tasks in the Quantum World

    NARCIS (Netherlands)

    Fehr, S.; Katz, J.; Song, F.; Zhou, H.S.; Zikas, V.; Sahai, A.

    2013-01-01

    It is known that cryptographic feasibility results can change by moving from the classical to the quantum world. With this in mind, we study the feasibility of realizing functionalities in the framework of universal composability, with respect to both computational and information-theoretic security

  1. Cryptographic Path Hardening: Hiding Vulnerabilities in Software through Cryptography

    CERN Document Server

    Ganesh, Vijay; Rinard, Martin

    2012-01-01

    We propose a novel approach to improving software security called Cryptographic Path Hardening, which is aimed at hiding security vulnerabilities in software from attackers through the use of provably secure and obfuscated cryptographic devices to harden paths in programs. By "harden" we mean that certain error-checking if-conditionals in a given program P are replaced by equivalent" we mean that adversaries cannot use semi-automatic program analysis techniques to reason about the hardened program paths and thus cannot discover as-yet-unknown errors along those paths, except perhaps through black-box dictionary attacks or random testing (which we can never prevent). Other than these unpreventable attack methods, we can make program analysis aimed at error-finding "provably hard" for a resource-bounded attacker, in the same sense that cryptographic schemes are hard to break. Unlike security-through-obscurity, in Cryptographic Path Hardening we use provably-secure crypto devices to hide errors and our mathemati...

  2. Cryptographic protocol verification using tractable classes of horn clauses

    DEFF Research Database (Denmark)

    Seidl, Helmut; Neeraj Verma, Kumar

    2007-01-01

    We consider secrecy problems for cryptographic protocols modeled using Horn clauses and present general classes of Horn clauses which can be efficiently decided. Besides simplifying the methods for the class of flat and onevariable clauses introduced for modeling of protocols with single blind...

  3. SPONGENT: The Design Space of Lightweight Cryptographic Hashing

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Knezevic, Miroslav; Leander, Gregor

    2013-01-01

    The design of secure yet efficiently implementable cryptographic algorithms is a fundamental problem of cryptography. Lately, lightweight cryptography--optimizing the algorithms to fit the most constrained environments--has received a great deal of attention, the recent research being mainly...

  4. On fairness in simulatability-based cryptographic systems

    NARCIS (Netherlands)

    Backes, M.; Hofheinz, D.; Müller-Quade, J.; Unruh, D.

    2005-01-01

    Simulatability constitutes the cryptographic notion of a secure refinement and has asserted its position as one of the fundamental concepts of modern cryptography. Although simulatability carefully captures that a distributed protocol does not behave any worse than an ideal specification, it however

  5. Symmetries and security of a quantum-public-key encryption based on single-qubit rotations

    CERN Document Server

    Seyfarth, U; Alber, G

    2012-01-01

    Exploring the symmetries underlying a previously proposed encryption scheme which relies on single-qubit rotations, we derive an improved upper bound on the maximum information that an eavesdropper might extract from all the available copies of the public key. Subsequently, the robustness of the scheme is investigated in the context of attacks that address each public-key qubit independently. The attacks under consideration make use of projective measurements on single qubits and their efficiency is compared to attacks that address many qubits collectively and require complicated quantum operations.

  6. A General Construction of IND-CCA2 Secure Public Key Encryption

    DEFF Research Database (Denmark)

    Kiltz, Eike; Malone-Lee, John

    2003-01-01

    We propose a general construction for public key encryption schemes that are IND-CCA2 secure in the random oracle model. We show that the scheme proposed in [1, 2] fits our general framework and moreover that our method of analysis leads to a more efficient security reduction.......We propose a general construction for public key encryption schemes that are IND-CCA2 secure in the random oracle model. We show that the scheme proposed in [1, 2] fits our general framework and moreover that our method of analysis leads to a more efficient security reduction....

  7. A General Construction of IND-CCA2 Secure Public Key Encryption

    DEFF Research Database (Denmark)

    Kiltz, Eike; Malone-Lee, John

    2003-01-01

    We propose a general construction for public key encryption schemes that are IND-CCA2 secure in the random oracle model. We show that the scheme proposed in [1, 2] fits our general framework and moreover that our method of analysis leads to a more efficient security reduction.......We propose a general construction for public key encryption schemes that are IND-CCA2 secure in the random oracle model. We show that the scheme proposed in [1, 2] fits our general framework and moreover that our method of analysis leads to a more efficient security reduction....

  8. Information hiding based on double random-phase encoding and public-key cryptography.

    Science.gov (United States)

    Sheng, Yuan; Xin, Zhou; Alam, Mohammed S; Xi, Lu; Xiao-Feng, Li

    2009-03-01

    A novel information hiding method based on double random-phase encoding (DRPE) and Rivest-Shamir-Adleman (RSA) public-key cryptosystem is proposed. In the proposed technique, the inherent diffusion property of DRPE is cleverly utilized to make up the diffusion insufficiency of RSA public-key cryptography, while the RSA cryptosystem is utilized for simultaneous transmission of the cipher text and the two phase-masks, which is not possible under the DRPE technique. This technique combines the complementary advantages of the DPRE and RSA encryption techniques and brings security and convenience for efficient information transmission. Extensive numerical simulation results are presented to verify the performance of the proposed technique.

  9. The Design, Analysis and Optimization of the REESSE1+ Public-key Cryptosystem

    CERN Document Server

    Su, Shenghui

    2007-01-01

    This paper gives the definition of a coprime sequence and the concept of the lever function, describes the five algorithms and six characteristics of the REESSE1+ public-key cryptosystem based on three new hardnesses: the modular subset product problem, the multivariate arrangement problem, and the super logarithm problem in a prime field, shows the correctness of the decryption and verification algorithms, and infers that the probability that a plaintext solution is not unique is nearly zeroth. The authors discuss necessity and sufficiency of the lever function for preventing a continued fraction attack, explain the relation between the lever function and a random oracle, and analyze the security of REESSE1+ against recovering a plaintext from a ciphertext, extracting a private key from a public key or a signature, and faking a digital signature via a public key or known signatures with a public key. On the basis of analysis, believe that the security of REESSE1+ is at least equal to the time complexity of O...

  10. Secret-Key Agreement with Public Discussion subject to an Amplitude Constraint

    KAUST Repository

    Zorgui, Marwen

    2016-04-06

    This paper considers the problem of secret-key agreement with public discussion subject to a peak power constraint A on the channel input. The optimal input distribution is proved to be discrete with finite support. To overcome the computationally heavy search for the optimal discrete distribution, several suboptimal schemes are proposed and shown numerically to perform close to the capacity. Moreover, lower and upper bounds for the secret-key capacity are provided and used to prove that the secret-key capacity converges for asymptotic high values of A, to the secret-key capacity with an average power constraint A2. Finally, when the amplitude constraint A is small (A ! 0), the secret-key capacity is proved to be asymptotically equal to the capacity of the legitimate user with an amplitude constraint A and no secrecy constraint.

  11. A generalization of Paillier's public-key system with applications to electronic voting

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Jurik, Mads Johan; Nielsen, Jesper Buus

    2010-01-01

    We propose a generalization of Paillier's probabilistic public-key system, in which the expansion factor is reduced and which allows to adjust the block length of the scheme even after the public key has been fixed, without losing the homomorphic property. We show that the generalization is as se......We propose a generalization of Paillier's probabilistic public-key system, in which the expansion factor is reduced and which allows to adjust the block length of the scheme even after the public key has been fixed, without losing the homomorphic property. We show that the generalization...... is as secure as Paillier's original system and propose several ways to optimize implementations of both the generalized and the original scheme. We construct a threshold variant of the generalized scheme as well as zero-knowledge protocols to show that a given ciphertext encrypts one of a set of given...... schemes. We show how the basic scheme for a yes/no vote can be easily adapted to casting a vote for up to t out of L candidates. The same basic building blocks can also be adapted to provide receipt-free elections, under appropriate physical assumptions. The scheme for 1 out of L elections can...

  12. A new notion of soundness in bare public-key model

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yunlei; ZHU Hong

    2003-01-01

    A new notion of soundness in bare public-key (BPK) model is presented. This new notion just lies in between one-time soundness and sequential soundness and its reasonableness is justified in the context of resettable zero-knowledge when resettable zero-knowledge prover is implemented by smart card.

  13. Gaussian elimination in split unitary groups with an application to public-key cryptography

    Directory of Open Access Journals (Sweden)

    Ayan Mahalanobis

    2017-07-01

    Full Text Available Gaussian elimination is used in special linear groups to solve the word problem. In this paper, we extend Gaussian elimination to split unitary groups. These algorithms have an application in building a public-key cryptosystem, we demonstrate that.

  14. Practical Cryptanalysis of a Public-key Encryption Scheme Based on New Multivariate Quadratic Assumptions

    DEFF Research Database (Denmark)

    Albrecht, Martin Roland; Faugére, Jean-Charles; Fitzpatrick, Robert

    2014-01-01

    In this paper, we investigate the security of a public-key encryption scheme introduced by Huang, Liu and Yang (HLY) at PKC’12. This new scheme can be provably reduced to the hardness of solving a set of quadratic equations whose coefficients of highest degree are chosen according to a discrete...

  15. Toekomstvaste fysieke toegangsystemen : Public Key Infrastructure als oplossing voor fysiek toegangbeheer

    NARCIS (Netherlands)

    Kleinhuis, G.; Olk, J.G.E.

    2011-01-01

    Voor fysieke toegangssystemen wordt veelal gebruik gemaakt van toegangspassen met een contactlose chip. Soms zijn deze passen ook nog voorzien van een PKI (Public Key Infrastructure) contactchip voor toegang tot ICT en/of het plaatsen van een digitale handtekening. Ook voor fysieke toegang bied PKI

  16. Toekomstvaste fysieke toegangsystemen : Public Key Infrastructure als oplossing voor fysiek toegangbeheer

    NARCIS (Netherlands)

    Kleinhuis, G.; Olk, J.G.E.

    2011-01-01

    Voor fysieke toegangssystemen wordt veelal gebruik gemaakt van toegangspassen met een contactlose chip. Soms zijn deze passen ook nog voorzien van een PKI (Public Key Infrastructure) contactchip voor toegang tot ICT en/of het plaatsen van een digitale handtekening. Ook voor fysieke toegang bied PKI

  17. Design of an Efficient Neural Key Distribution Centre

    CERN Document Server

    Bisalapur, Sahana S

    2011-01-01

    The goal of any cryptographic system is the exchange of information among the intended users without any leakage of information to others who may have unauthorized access to it. A common secret key could be created over a public channel accessible to any opponent. Neural networks can be used to generate common secret key. In case of neural cryptography, both the communicating networks receive an identical input vector, generate an output bit and are trained based on the output bit. The two networks and their weight vectors exhibit a novel phenomenon, where the networks synchronize to a state with identical time-dependent weights. The generated secret key over a public channel is used for encrypting and decrypting the information being sent on the channel. This secret key is distributed to the other vendor efficiently by using an agent based approach.

  18. [Screening on key techniques used for surveillance and disposal of public health emergencies].

    Science.gov (United States)

    Zhu, Q R; Yang, L; Ma, H Y; Xie, W Q; Cong, L M; Xu, L W

    2017-06-10

    Objective: To explore the key techniques used for surveillance and disposal of infectious diseases, food poisoning and hospital infection to improve the ability of surveillance and disposal on public health emergency. Methods: Framework on surveillance and disposal of infectious diseases, food poisoning and hospital infection was set up, based on literature review and expert group discussion. Delphi method and technique for order preference by similarity to ideal solution comprehensive evaluation method were used for ordering preference by similarity, to screen key techniques set for surveillance and disposal of the above said events. Results: Framework to be used for selecting key techniques was designed, based on the classification of emergency events, processing cycle of emergency events and level of techniques. Twenty six public health experts were selected for a 2-round consultation, with their authority as 0.796. Ten key techniques with important significance for surveillance and disposal of infectious diseases, food poisoning and hospital infection were selected from each event. Among these key techniques, the early-warning system was recognized as the key technique, important for the surveillance and disposal of all three emergency events. Items as technology used for unknown pathogenic microorganism detection, personal protection, gene sequencing and tracing technology, microorganism molecular typing technology, nucleic acid detection technology etc. were the key techniques and need to develop for the surveillance and disposal of infectious diseases and iatrogenic infection. Data regarding key technologies on security and privacy, early warning and forecasting, field rapid detection were sorted out that all in need to improve the surveillance programs on disposal of infectious diseases and food poisoning. Data exchange appeared another key technique on infectious diseases, with toxin detection and other 5 techniques the key techniques for food poisoning

  19. BITRU: Binary Version of the NTRU Public Key Cryptosystem via Binary Algebra

    Directory of Open Access Journals (Sweden)

    Nadia M.G. Alsaidi

    2016-11-01

    Full Text Available New terms such as closest vector problem (CVP and the shortest vector problem (SVP, which have been illustrated as NP-hard problem, emerged, leading to a new hope for designing public key cryptosystem based on certain lattice hardness. A new cryptosystem called NTRU is proven computationally efficient and it can be implemented with low cost. With these characteristics, NTRU possesses advantage over others system that rely on number-theoretical problem in a finite field (e.g. integer factorization problem or discrete logarithm problem. These advantages make NTRU a good choice for many applications. After the adaptation of NTRU, many attempts to generalize its algebraic structure have appeared. In this study, a new variant of the NTRU public key cryptosystem called BITRU is proposed. BITRU is based on a new algebraic structure used as an alternative to NTRU-mathematical structure called binary algebra. This commutative and associative. Establishing two public keys in the proposed system has distinguished it from NTRU and those similar to NTRU cryptosystems. This new structure helps to increase the security and complexity of BITRU. The clauses of BITRU, which include key generation, encryption, decryption, and decryption failure, are explained in details. Its suitability of the proposed system is proven and its security is demonstrated by comparing it with NTRU.

  20. On another two cryptographic identities in universal Osborn loops

    Directory of Open Access Journals (Sweden)

    T. G. Jaiyéolá

    2010-03-01

    Full Text Available In this study, by establishing an identity for universal Osborn loops, two other identities (of degrees 4 and 6 are deduced from it and they are recognized and recommended for cryptography in a similar spirit in which the cross inverse property (of degree 2 has been used by Keedwell following the fact that it was observed that universal Osborn loops that do not have the 3-power associative property or weaker forms of; inverse property, power associativity and diassociativity to mention a few, will have cycles (even long ones. These identities are found to be cryptographic in nature for universal Osborn loops and thereby called cryptographic identities. They were also found applicable to security patterns, arrangements and networks which the CIP may not be applicable to.

  1. AN INTERACTIVE VISUALIZATION TOOL FOR ANIMATING BEHAVIOR OF CRYPTOGRAPHIC PROTOCOLS

    Directory of Open Access Journals (Sweden)

    Mabroka Maeref

    2015-03-01

    Full Text Available Cryptography and Network Security is a difficult subject to understand, mainly because of the complexity of security protocols and the mathematical rigour required to understand encryption algorithms. Realizing the need for an interactive visualization tool to facilitate the understanding of cryptographic concepts and protocols, several tools had been developed. However, these tools cannot be easily adapted to animate different protocols. The aim of this paper is to propose an interactive visualization tool, called the Cryptographic Protocol Animator (CPAnim. The tool enables a student to specify a protocol and gain knowledge about the impact of its behavior. The protocol is specified by using a scenario-based approach and it is demonstrated as a number of scenes displaying a complete scenario. The effectiveness of this tool was tested using an empirical evaluation method. The results show that this tool was effective in meeting its learning objectives.

  2. Algebraic Construction and Cryptographic Properties of Rijndael Substitution Box

    Directory of Open Access Journals (Sweden)

    Shristi Deva Sinha

    2012-01-01

    Full Text Available Rijndael algorithm was selected as the advanced encryption standard in 2001 after five year long security evaluation; it is well proven in terms of its strength and efficiency. The substitution box is the back bone of the cipher and its strength lies in the simplicity of its algebraic construction. The present paper is a study of the construction of Rijndael Substitution box and the effect of varying the design components on its cryptographic properties.

  3. Increasing Ranks of Linear Finite Automata and Complexity of FA Public Key Cryptosystem

    Institute of Scientific and Technical Information of China (English)

    鲍丰

    1994-01-01

    The encryption algorithm of finite automata (FA) public key cryptosystem is implemented by a weakly invertible finite automata (WIFA) which is composed of a nonlinear WIFA with delay 0 and a linear WIFA with delay τ. In this paper, we proved that such an automaton bears the same properties as the linear WIFA and the increasing ranks of the latter are key factors to affecting the former. A probabilistic algorithm is given to realize a ciphertext attack, and its complexity is analysed through the increasing ranks of the linear WIFA. The size of the parameters for safe linear WIFA is estimated.

  4. IMPLEMENTATION OF NEURAL - CRYPTOGRAPHIC SYSTEM USING FPGA

    Directory of Open Access Journals (Sweden)

    KARAM M. Z. OTHMAN

    2011-08-01

    Full Text Available Modern cryptography techniques are virtually unbreakable. As the Internet and other forms of electronic communication become more prevalent, electronic security is becoming increasingly important. Cryptography is used to protect e-mail messages, credit card information, and corporate data. The design of the cryptography system is a conventional cryptography that uses one key for encryption and decryption process. The chosen cryptography algorithm is stream cipher algorithm that encrypt one bit at a time. The central problem in the stream-cipher cryptography is the difficulty of generating a long unpredictable sequence of binary signals from short and random key. Pseudo random number generators (PRNG have been widely used to construct this key sequence. The pseudo random number generator was designed using the Artificial Neural Networks (ANN. The Artificial Neural Networks (ANN providing the required nonlinearity properties that increases the randomness statistical properties of the pseudo random generator. The learning algorithm of this neural network is backpropagation learning algorithm. The learning process was done by software program in Matlab (software implementation to get the efficient weights. Then, the learned neural network was implemented using field programmable gate array (FPGA.

  5. Efficient RSA Key Generation and Threshold Paillier in the Two-Party Setting

    DEFF Research Database (Denmark)

    Hazay, Carmit; Mikkelsen, Gert Læssøe; Rabin, Tal

    2011-01-01

    The problem of generating an RSA composite in a distributed manner without leaking its factorization is particularly challenging and useful in many cryptographic protocols. Our first contribution is the first non-generic fully simulatable protocol for distributively generating an RSA composite...... generation is comprised of the following: (i) a distributed protocol for generation of an RSA composite, and (ii) a biprimality test for verifying the validity of the generated composite. Our Paillier threshold encryption scheme uses the RSA composite as public key and is comprised of: (i) a distributed...... generation of the corresponding secret-key shares and, (ii) a distributed decryption protocol for decrypting according to Paillier....

  6. Cryptanalysis of the public key encryption based on multiple chaotic systems

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Linhua [College of Mathematics and Computer, Chongqing Normal University, Chongqing, 400047 (China)], E-mail: Linzhang@cqu.edu.cn

    2008-08-15

    Recently, Ranjan proposed a novel public key encryption technique based on multiple chaotic systems [Phys Lett 2005;95]. Unfortunately, Wang soon gave a successful attack on its special case based on Parseval's theorem [Wang K, Pei W, Zhou L, et al. Security of public key encryption technique based on multiple chaotic system. Phys Lett A, in press]. In this letter, we give an improved example which can avoid the attack and point out that Wang cannot find the essential drawback of the technique. However, further experimental result shows Ruanjan's encryption technique is inefficient, and detailed theoretic analysis shows that the complexity to break the cryptosystem is overestimated.

  7. Comparison of Certificate Policies Formerging Public Key Infrastructuresduring Merger and Acquisition of Companies

    Directory of Open Access Journals (Sweden)

    Balachandra Muniyal

    2012-10-01

    Full Text Available The Public Key Infrastructure(PKI provides facilities for data encryption, digital signature and timestamping. It is a system where different authorities verify and authenticate the validity of each participantwith the use of digital certificates. A Certificate Policy (CP is a named set of rules and it indicatesthe applicability of a certificate in a Public Key Infrastructure. Sometimes two companies or organizationswith different PKIs merge. Therefore it would be necessary that their PKIs are also able to merge.Sometimes, the unification of different PKIs is not possible because of the different certificate policies.This paper presents a method to compare and assess certificate policies during merger and acquisitionof companies.

  8. Public key Steganography Using Discrete Cross-Coupled One-Dimensional Chaotic Maps

    Directory of Open Access Journals (Sweden)

    Mahdiyeh Majidpour

    2013-07-01

    Full Text Available By cross-coupling two one-dimensional chaotic maps a novel method is proposed for the public key steganography in JPEG image. Chaotic maps entail high complexity in the used algorithm for embedding secret data in a medium. In this paper, discrete cross-coupled chaotic maps are used to specifying the location of the different parts of the secret data in the image. Modifying JPEG format during compressing and decompressing, and also using public key enhanced difficulty of the algorithm. Simulation results show that in addition to excessive capacity, this method has high robustness and resistance against hackers and can be applicable in secret communication. Also the PSNR value is high compared to the other works.

  9. A Generalisation, a Simplification and some Applications of Paillier's Probabilistic Public-Key System

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Jurik, Mads Johan

    2001-01-01

    to t out of L candidates. The same basic building blocks can also be adapted to provide receipt-free elections, under appropriate physical assumptions. The scheme for 1 out of L elections can be optimised such that for a certain range of parameter values, a ballot has size only O(log L) bits.......We propose a generalisation of Paillier's probabilistic public key system, in which the expansion factor is reduced and which allows to adjust the block length of the scheme even after the public key has been fixed, without loosing the homomorphic property. We show that the generalisation...... blocks can be used for applying the scheme to efficient electronic voting. This reduces dramatically the work needed to compute the final result of an election, compared to the previously best known schemes. We show how the basic scheme for a yes/no vote can be easily adapted to casting a vote for up...

  10. [Translational research in geriatrics? A plea based on current biomedical key publications].

    Science.gov (United States)

    Bollheimer, L C; Volkert, D; Bertsch, T; Bauer, J; Klucken, J; Sieber, C C; Büttner, R

    2013-08-01

    Contemporary geriatric research focuses mainly on observational clinical studies and epidemiological surveys and the translation of basic scientific results from biogerontology into a clinical context is often neglected. Following a definition of translational research the article gives an overview of recent key publications in experimental biogerontology with a special emphasis on their relevance for clinical geriatrics. The topics dealt with include age-induced loss of skeletal muscle (sarcopenia), the aging immune system (immunosenescence) and neurodegenerative disorders (Alzheimer's and Parkinson's disease).

  11. Stakeholders' perception of key performance indicators (KPIs) of public-private partnership (PPP) projects

    OpenAIRE

    Olabode Emmanuel Ogunsanmi

    2013-01-01

    The study investigates key performance indicators (KPIs) that could improve performance of public-private partnership (PPP) projects in Nigeria. The study objectives include a comparison of stakeholders’ perception on KPIs and to investigate if significant difference exists between stakeholders’ perceptions on most KPIs. A structured questionnaire was used to collect information from various respondents who were recently involved in PPP projects. Random sampling technique was used to select f...

  12. Securing U-Healthcare Sensor Networks using Public Key Based Scheme

    CERN Document Server

    Haque, Md Mokammel; Hong, Choong Seon

    2008-01-01

    Recent emergence of electronic culture uplifts healthcare facilities to a new era with the aid of wireless sensor network (WSN) technology. Due to the sensitiveness of medical data, austere privacy and security are inevitable for all parts of healthcare systems. However, the constantly evolving nature and constrained resources of sensors in WSN inflict unavailability of a lucid line of defense to ensure perfect security. In order to provide holistic security, protections must be incorporated in every component of healthcare sensor networks. This paper proposes an efficient security scheme for healthcare applications of WSN which uses the notion of public key cryptosystem. Our entire security scheme comprises basically of two parts; a key handshaking scheme based on simple linear operations and the derivation of decryption key by a receiver node for a particular sender in the network. Our architecture allows both base station to node or node to base station secure communications, and node-to-node secure commun...

  13. Non-coherent capacity of secret-key agreement with public discussion

    KAUST Repository

    Agrawal, Anurag

    2011-06-01

    We study the Rayleigh fading non-coherent capacity of secret-key agreement with public discussion, where neither the sender nor the receivers have access to instantaneous channel state information (CSI) of any channel. We present two results. At high Signal-to-Noise Ratio (SNR), the secret-key capacity is bounded in SNR, regardless of the number of antennas at each terminal. Second, for a system with a single antenna at both the legitimate and the eavesdropper terminals and an arbitrary number of transmit antennas, the secret-key capacity-achieving input distribution is discrete, with a finite number of mass points. Numerically we observe that at low-SNR, the capacity achieving distribution has two mass points with one of them at the origin. © 2011 IEEE.

  14. Secured Wireless Communication using Fuzzy Logic based High Speed Public-Key Cryptography (FLHSPKC

    Directory of Open Access Journals (Sweden)

    Arindam Sarkar

    2012-10-01

    Full Text Available In this paper secured wireless communication using fuzzy logic based high speed public-key cryptography (FLHSPKC has been proposed by satisfying the major issues likes computational safety, power management and restricted usage of memory in wireless communication. Wireless Sensor Network (WSN has several major constraints likes’ inadequate source of energy, restricted computational potentiality and limited memory. Though conventional Elliptic Curve Cryptography (ECC which is a sort of public-key cryptography used in wireless communication provides equivalent level of security like other existing public–key algorithm using smaller parameters than other but this traditional ECC does not take care of all these major limitations in WSN. In conventional ECC consider Elliptic curve point p, an arbitrary integer k and modulus m, ECC carry out scalar multiplication kP mod m, which takes about 80% of key computation time on WSN. In this paper proposed FLHSPKC scheme provides some novel strategy including novel soft computing based strategy to speed up scalar multiplication in conventional ECC and which in turn takes shorter computational time and also satisfies power consumption restraint, limited usage of memory without hampering the security level. Performance analysis of the different strategies under FLHSPKC scheme and comparison study with existing conventional ECC methods has been done.

  15. Key Data Gaps Regarding the Public Health Issues Associated with Opioid Analgesics.

    Science.gov (United States)

    Schmidt, Teresa D; Haddox, J David; Nielsen, Alexandra E; Wakeland, Wayne; Fitzgerald, John

    2015-10-01

    Most pharmaceutical opioids are used to treat pain, and they have been demonstrated to be effective medications for many. Their abuse and misuse pose significant public health concerns in the USA. Research has provided much insight into the prevalence, scope, and drivers of opioid abuse, but a holistic understanding is limited by a lack of available data regarding key aspects of this public health problem. Twelve data gaps were revealed during the creation of a systems-level computer model of medical use, diversion, nonmedical use, and the adverse outcomes associated with opioid analgesics in the USA. Data specific to these gaps would enhance the validity and real-world applications of systems-level models of this public health problem and would increase understanding of the complex system in which use and abuse occur. This paper provides an overview of these gaps, argues for the importance of closing them, and provides specific recommendations for future data collection efforts.

  16. HIGHLY SECURE KEY PREDISTRIBUTION USING AFFINE PLANES AND REED MULLER CODES IN WIRELESS SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    Pinaki Sarkar

    2011-10-01

    Full Text Available Wireless Sensor Networks (WSN consist of low powered and resource constrained sensor nodes which are left unattended for long duration of time. Hence it is very challenging to design and implement cost effective security protocols for such networks. Thus symmetric key cryptographic techniques are preferred over public key techniques for communication in such scenarios. Prior to deployment, keys are usually predistributed into the nodes and this problem has been well studied. Highlighting that connectivity and communication are two separate aspects of a WSN, we propose a secure connectivity model using Reed Muller codes. The model is then utilized to securely establish communication keys and exchange messages in a WSN designed on the basis of a scheme that uses affine planes for key predistribution. By the introduction of connectivity model, the node identifiers (ids are converted from public to private information to each node. These private node ids can be used to generate new communication keys from old ones by applying cryptographic hash functions. Novel combination of these ideas yields highly resilient communication model with full connectivity between nodes.

  17. Automated information extraction of key trial design elements from clinical trial publications.

    Science.gov (United States)

    de Bruijn, Berry; Carini, Simona; Kiritchenko, Svetlana; Martin, Joel; Sim, Ida

    2008-11-06

    Clinical trials are one of the most valuable sources of scientific evidence for improving the practice of medicine. The Trial Bank project aims to improve structured access to trial findings by including formalized trial information into a knowledge base. Manually extracting trial information from published articles is costly, but automated information extraction techniques can assist. The current study highlights a single architecture to extract a wide array of information elements from full-text publications of randomized clinical trials (RCTs). This architecture combines a text classifier with a weak regular expression matcher. We tested this two-stage architecture on 88 RCT reports from 5 leading medical journals, extracting 23 elements of key trial information such as eligibility rules, sample size, intervention, and outcome names. Results prove this to be a promising avenue to help critical appraisers, systematic reviewers, and curators quickly identify key information elements in published RCT articles.

  18. An efficient and provably-secure certificateless public key encryption scheme for telecare medicine information systems.

    Science.gov (United States)

    Guo, Rui; Wen, Qiaoyan; Shi, Huixian; Jin, Zhengping; Zhang, Hua

    2013-10-01

    Telecare Medicine Information Systems (TMIS) promote the traditional medical and healthcare services by information and communication technology. Since the physician and caregiver can monitor the patient's physiological condition remotely in TMIS, the confidentiality of this sensitive data should be protected, which is the key issue in the Health Insurance Portability and Accountability Act. In this paper, we propose an efficient certificateless public key encryption scheme without bilinear pairing for TMIS. Our proposal is proved to be secure in the random oracle model under the hardness assumption of computational Diffie-Hellman problem. Moreover, after modifying the original model of the certificateless encryption, this scheme achieves Girault's trust level 3. Compared with the related protocols, the perform evaluations show that our scheme is more efficient and appropriate to collocate with low power mobile devices for TMIS.

  19. On the Security of a Simple Three-Party Key Exchange Protocol without Server’s Public Keys

    Directory of Open Access Journals (Sweden)

    Junghyun Nam

    2014-01-01

    Full Text Available Authenticated key exchange protocols are of fundamental importance in securing communications and are now extensively deployed for use in various real-world network applications. In this work, we reveal major previously unpublished security vulnerabilities in the password-based authenticated three-party key exchange protocol according to Lee and Hwang (2010: (1 the Lee-Hwang protocol is susceptible to a man-in-the-middle attack and thus fails to achieve implicit key authentication; (2 the protocol cannot protect clients’ passwords against an offline dictionary attack; and (3 the indistinguishability-based security of the protocol can be easily broken even in the presence of a passive adversary. We also propose an improved password-based authenticated three-party key exchange protocol that addresses the security vulnerabilities identified in the Lee-Hwang protocol.

  20. Cryptographically Blinded Games: Leveraging Players' Limitations for Equilibria and Profit

    DEFF Research Database (Denmark)

    Hubacek, Pavel; Park, Sunoo

    2014-01-01

    In this work we apply methods from cryptography to enable mutually distrusting players to implement broad classes of mediated equilibria of strategic games without trusted mediation. Our implementation uses a pre-play 'cheap talk' phase, consisting of non- binding communication between players pr...... prior to play in the original game. In the cheap talk phase, the players run a secure multi-party computation protocol to sample from an equilibrium of a "cryptographically blinded" version of the game, in which actions are encrypted...

  1. Algebraic Construction and Cryptographic Properties of Rijndael Substitution Box

    Directory of Open Access Journals (Sweden)

    Shristi Deva Sinha

    2012-01-01

    Full Text Available Rijndael algorithm was selected as the advanced encryption standard in 2001 after five year long security evaluation; it is well proven in terms of its strength and efficiency. The substitution box is the back bone of the cipher and its strength lies in the simplicity of its algebraic construction. The present paper is a study of the construction of Rijndael Substitution box and the effect of varying the design components on its cryptographic properties.Defence Science Journal, 2012, 62(1, pp.32-37, DOI:http://dx.doi.org/10.14429/dsj.62.1439

  2. Research of Cryptographic Algorithms Applied in Electronic Commerce

    Directory of Open Access Journals (Sweden)

    Cheng Zengping

    2014-02-01

    Full Text Available With the developments of network communication, electronic commerce plays a more and more role in the trade business and industry structure. The requirement for the electronic commerce turns to be higher. In this study, we study current status about the cryptographic algorithms exploited in electronic commerce. We discuss the advantages and disadvantages about the symmetric and asymmetric algorithms and improve them. Then we give a new scheme that combines the improved symmetric algorithm and asymmetric algorithm. We give sound reasons to explain why our scheme is more secure. Finally, we carry the experiments to show the security of our scheme.

  3. A brief history of cryptology and cryptographic algorithms

    CERN Document Server

    Dooley, John F

    2013-01-01

    The science of cryptology is made up of two halves. Cryptography is the study of how to create secure systems for communications. Cryptanalysis is the study of how to break those systems. The conflict between these two halves of cryptology is the story of secret writing. For over 2,000 years, the desire to communicate securely and secretly has resulted in the creation of numerous and increasingly complicated systems to protect one's messages. Yet for every system there is a cryptanalyst creating a new technique to break that system. With the advent of computers the cryptographer seems to final

  4. Enhanced Montgomery Multiplication on DSP Architectures for Embedded Public-Key Cryptosystems

    Directory of Open Access Journals (Sweden)

    Gastaldo P

    2008-01-01

    Full Text Available Abstract Montgomery's algorithm is a popular technique to speed up modular multiplications in public-key cryptosystems. This paper tackles the efficient support of modular exponentiation on inexpensive circuitry for embedded security services and proposes a variant of the finely integrated product scanning (FIPS algorithm that is targeted to digital signal processors. The general approach improves on the basic FIPS formulation by removing potential inefficiencies and boosts the exploitation of computing resources. The reformulation of the basic FIPS structure results in a general approach that balances computational efficiency and flexibility. Experimental results on commercial DSP platforms confirm both the method's validity and its effectiveness.

  5. In science communication, why does the idea of the public deficit always return? Exploring key influences.

    Science.gov (United States)

    Suldovsky, Brianne

    2016-05-01

    Despite mounting criticism, the deficit model remains an integral part of science communication research and practice. In this article, I advance three key factors that contribute to the idea of the public deficit in science communication, including the purpose of science communication, how communication processes and outcomes are conceptualized, and how science and scientific knowledge are defined. Affording science absolute epistemic privilege, I argue, is the most compelling factor contributing to the continued use of the deficit model. In addition, I contend that the deficit model plays a necessary, though not sufficient, role in science communication research and practice. Areas for future research are discussed.

  6. Dynamic Group Diffie-Hellman Key Exchange under standard assumptions

    Energy Technology Data Exchange (ETDEWEB)

    Bresson, Emmanuel; Chevassut, Olivier; Pointcheval, David

    2002-02-14

    Authenticated Diffie-Hellman key exchange allows two principals communicating over a public network, and each holding public-private keys, to agree on a shared secret value. In this paper we study the natural extension of this cryptographic problem to a group of principals. We begin from existing formal security models and refine them to incorporate major missing details (e.g., strong-corruption and concurrent sessions). Within this model we define the execution of a protocol for authenticated dynamic group Diffie-Hellman and show that it is provably secure under the decisional Diffie-Hellman assumption. Our security result holds in the standard model and thus provides better security guarantees than previously published results in the random oracle model.

  7. Key handling in wireless sensor networks

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y; Newe, T [Optical Fibre Sensors Research Centre, Department of Electronic and Computer Engineering, University of Limerick, Limerick (Ireland)

    2007-07-15

    With the rapid growth of Wireless Sensor Networks (WSNs), many advanced application areas have received significant attention. However, security will be an important factor for their full adoption. Wireless sensor nodes pose unique challenges and as such traditional security protocols, used in traditional networks cannot be applied directly. Some new protocols have been published recently with the goal of providing both privacy of data and authentication of sensor nodes for WSNs. Such protocols can employ private-key and/or public key cryptographic algorithms. Public key algorithms hold the promise of simplifying the network infrastructure required to provide security services such as: privacy, authentication and non-repudiation, while symmetric algorithms require less processing power on the lower power wireless node. In this paper a selection of key establishment/agreement protocols are reviewed and they are broadly divided into two categories: group key agreement protocols and pair-wise key establishment protocols. A summary of the capabilities and security related services provided by each protocol is provided.

  8. The EU Clinical Trials Regulation: key priorities, purposes and aims and the implications for public health.

    Science.gov (United States)

    Flear, Mark L

    2016-03-01

    The replacement of the European Union (EU) Clinical Trials Directive by the new Clinical Trials Regulation (CTR), which entered into force on 16 June 2014 but will not apply before 28 May 2016, provides an opportunity to review the legal and political context within which this important aspect of research law and policy sits and to reflect on the implications for public health. My aim in this article is to relate the context to the key purposes and aims of EU law and policy on clinical trials in order to explain and clarify its orientation. On that basis, I argue that the CTR and the changes it introduces to the law on clinical trials are part of the EU's continued focus on market optimisation. It is this focus that orients and directs the wider pharmaceutical development pipeline, but that undermines the achievement of key public health objectives. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  9. Breaking Classical Public Key Cryptosystems by Using a Novel Ensemble Search Algorithm

    CERN Document Server

    Chen, C Y

    2004-01-01

    In this paper, we improve Bruschweiler's algorithm such that only one query is needed for searching the single object z from N=2^n unsorted elements. Our algorithm construct the new oracle query function g(.) satisfying g(x)=0 for all input x, except for one, say x=z, where g(z)=z. To store z, our algorithm extends from one ancillary qubit to n ancillary qubits. We then measure these ancillary qubits to discover z. We further use our ensemble search algorithm to attack classical public key cryptosystems. Given the ciphertext C=Ek(m, r) which is generated by the encryption function Ek(), a public key k, a message m, and a random number r, we can construct an oracle query function h(.) satisfying h(m', r')=0 if Ek(m', r')!=C and h(m', r')= (m', r') if Ek(m', r')=C. There is only one object, say (m, r), can be discovered in decryption of C. By preparing the input with all possible states of (m', r'), we can thus use our ensemble search algorithm to find the wanted object (m, r). Obviously, we break the classical...

  10. Secure management of biomedical data with cryptographic hardware.

    Science.gov (United States)

    Canim, Mustafa; Kantarcioglu, Murat; Malin, Bradley

    2012-01-01

    The biomedical community is increasingly migrating toward research endeavors that are dependent on large quantities of genomic and clinical data. At the same time, various regulations require that such data be shared beyond the initial collecting organization (e.g., an academic medical center). It is of critical importance to ensure that when such data are shared, as well as managed, it is done so in a manner that upholds the privacy of the corresponding individuals and the overall security of the system. In general, organizations have attempted to achieve these goals through deidentification methods that remove explicitly, and potentially, identifying features (e.g., names, dates, and geocodes). However, a growing number of studies demonstrate that deidentified data can be reidentified to named individuals using simple automated methods. As an alternative, it was shown that biomedical data could be shared, managed, and analyzed through practical cryptographic protocols without revealing the contents of any particular record. Yet, such protocols required the inclusion of multiple third parties, which may not always be feasible in the context of trust or bandwidth constraints. Thus, in this paper, we introduce a framework that removes the need for multiple third parties by collocating services to store and to process sensitive biomedical data through the integration of cryptographic hardware. Within this framework, we define a secure protocol to process genomic data and perform a series of experiments to demonstrate that such an approach can be run in an efficient manner for typical biomedical investigations.

  11. Key Performance Indicators for Maintenance Management Effectiveness of Public Hospital Building

    Directory of Open Access Journals (Sweden)

    Farhana Omar Mardhiah

    2017-01-01

    Full Text Available Effectiveness of management in maintenance aspect holds the key element in influencing the performance of overall maintenance management. Similarly, public hospital building needs an effective maintenance management as this type of building in nature is one of the most complex issues in the field of maintenance. Improper building maintenance management adopted by the organization significantly will interrupt the overall operation of the building. Therefore, this paper is aim to identifying the key performance indicator (KPI of effectiveness of maintenance management for the public hospital building. A total of 32 set of questionnaires were distributed to the maintenance manager for each hospital in the northern region of peninsular Malaysia by using self-administration strategy. The survey answer was analyzed by performing descriptive analysis in SPSS. Overall, the result of descriptive analysis shows that all the ten factors of effectiveness of maintenance management are accepted as KPI since the mean value is at least 3.93 which classified as important and significant. The most significant factor of effectiveness of maintenance management is task planning and scheduling with the mean score of 4.35. While less significant factor is identify as maintenance approach with the value of mean score is 3.93. The both results indicates that the management need to have well-structured planning for the maintenance works and also need to embrace the exact strategy of maintenance approach in order to achieved better overall performance of maintenance management. This study may draw a standard practice for the government in assessing the performance of public facilities in terms of maintenance management.

  12. Understanding key influencers' attitudes and beliefs about healthy public policy change for obesity prevention.

    Science.gov (United States)

    Raine, Kim D; Nykiforuk, Candace I J; Vu-Nguyen, Karen; Nieuwendyk, Laura M; VanSpronsen, Eric; Reed, Shandy; Wild, T Cameron

    2014-11-01

    As overweight and obesity is a risk factor for chronic diseases, the development of environmental and healthy public policy interventions across multiple sectors has been identified as a key strategy to address this issue. In 2009, a survey was developed to assess the attitudes and beliefs regarding health promotion principles, and the priority and acceptability of policy actions to prevent obesity and chronic diseases, among key policy influencers in Alberta and Manitoba, Canada. Surveys were mailed to 1,765 key influencers from five settings: provincial government, municipal government, school boards, print media companies, and workplaces with greater than 500 employees. A total of 236 surveys were completed with a response rate of 15.0%. Findings indicate nearly unanimous influencer support for individual-focused policy approaches and high support for some environmental policies. Restrictive environmental and economic policies received weakest support. Obesity was comparable to smoking with respect to perceptions as a societal responsibility versus a personal responsibility, boding well for the potential of environmental policy interventions for obesity prevention. This level of influencer support provides a platform for more evidence to be brokered to policy influencers about the effectiveness of environmental policy approaches to obesity prevention. © 2014 The Obesity Society.

  13. A New Public-key Oblivious Fragile Watermarking for Image Authentication Using Discrete Cosine Transform

    Directory of Open Access Journals (Sweden)

    Chin-Chen Chang

    2009-03-01

    Full Text Available In this paper, a new oblivious fragile watermarking using discrete cosine transform is proposed. It is inspired by Wong's public key watermarking scheme proposed in 1998 and aims to improve its vulnerability towards possible attacks indicated by Barreto and Holliman. Instead of making use of contextual information and making it an inter-block dependent scheme, as suggested by Barreto, we adopt another approach to retain its blockwise independent property. Our scheme can avoid the conditions necessary for such attacks to befeasible. Furthermore, our scheme extracts the inherent image features and embeds them into this image as the watermark. This relieves users from having to maintain a database of watermarks from various sources. Experimental results show that the watermark insertion procedure has little effect on the visual quality of the watermarked image. They also show our scheme can locate the modifications made to the watermarked image, including imagescaling, cropping, geometric distortion, pixel value changes, etc.

  14. Secure Digital Certificate Design Based on the Public Key Cryptography Algorithm

    Directory of Open Access Journals (Sweden)

    Zhang Qi ming

    2013-07-01

    Full Text Available     With the popularity of the Internet, more and more people choose online shopping, however, in the case of lacking security measures, there is a great deal of risk on the Internet. to this situation,In response to this situation, this paper presents a digital certificate based on the X.509 standard. This paper uses the C language generation public key algorithm (RSA,Realization of the digital certificate registration, verification and certificate generation process,the identity of certification users can be verified and provide proof of identity on the Internet transactions ,reducing the transaction risks greatly , ensuring the user's property and interests are not infringed.

  15. Funding ATLAS 2012 key indicators for publicly funded research in Germany

    CERN Document Server

    Deutsche Forschungsgemeinschaft (DFG)

    2013-01-01

    The Funding ATLAS is a reporting system (previously referred to as the Funding Ranking) employed by the German Research Foundation (DFG) to provide information in the form of indicators of key developments in publicly funded research in Germany every three years. This English version of the Funding ATLAS 2012 presents selected findings from the more comprehensive German edition. At the core of the report are indicators that provide information on which subject areas have received funding at higher education and other research institutions in the period 2008-2010. This report also includes, as a supplement not found in the German edition, the decisions on the Excellence Initiative, which were taken shortly after the German edition of the Funding ATLAS 2012 was published. The report also addresses the subject of internationality by presenting selected indicators that show how attractive Germany's research institutions are for visiting scientists. In summary, the DFG Funding ATLAS furnishes reliable indicators o...

  16. Health and safety's stewardship of key business values: employees, public trust, and responsibility to shareholders.

    Science.gov (United States)

    Fulwiler, R D

    1993-11-01

    This paper reviews how one company has been able to develop and implement a highly effective job safety and health system and to sustain it at a high level of performance. This process begins with a simple but clear corporate safety and health policy statement: "Procter & Gamble insists on safe operation." It is driven by three critical values, namely: 1) its employees, 2) its public trust, and 3) its profits. The impact of workers' compensation costs on company profits is examined, along with the enormous savings in these costs that have been achieved by the company's commitment to total quality. This is followed by brief descriptions of the company's "Total Incident Rate" and it's "Key Elements" systems, and the relationships between them. The paper concludes with a description of the company's model for enabling all employees to make recommendations for continuous improvement of health and safety systems throughout all of the company's operations.

  17. Healthcare public key infrastructure (HPKI) and non-profit organization (NPO): essentials for healthcare data exchange.

    Science.gov (United States)

    Takeda, Hiroshi; Matsumura, Yasushi; Nakagawa, Katsuhiko; Teratani, Tadamasa; Qiyan, Zhang; Kusuoka, Hideo; Matsuoka, Masami

    2004-01-01

    To share healthcare information and to promote cooperation among healthcare providers and customers (patients) under computerized network environment, a non-profit organization (NPO), named as OCHIS, was established at Osaka, Japan in 2003. Since security and confidentiality issues on the Internet have been major concerns in the OCHIS, the system has been based on healthcare public key infrastructure (HPKI), and found that there remained problems to be solved technically and operationally. An experimental study was conducted to elucidate the central and the local function in terms of a registration authority and a time stamp authority by contracting with the Ministry of Economics and Trading Industries in 2003. This paper describes the experimental design with NPO and the results of the study concerning message security and HPKI. The developed system has been operated practically in Osaka urban area.

  18. [Reversal of aging and lifespan elongation. Current biomedical key publications and the implications for geriatrics].

    Science.gov (United States)

    Bollheimer, L C; Volkert, D; Bertsch, T; Sieber, C C; Büttner, R

    2013-08-01

    Biological aging means a time-dependent accumulation of changes to which a living organism is being exposed during its lifetime. Biological aging normally concurs with chronological aging the time frame of which is set by an upper limit, the lifespan (in humans approximately 120 years). New findings in experimental biogerontology are challenging both the dogma of irreversibility of biological aging and the preset species-specific limitations of life. The present overview first explains the general principle of rejuvenation and reversal of biological aging with paradigms from stem cell research. Secondly, recent key publications on artificial telomerase elongation and (alleged) lifespan enhancement by sirtuins and resveratrol will be discussed with an emphasis on the implications for (future) geriatric medicine.

  19. 一种新的公钥基础设施——SPKI%A New Public Key Infrastructure - SPKI

    Institute of Scientific and Technical Information of China (English)

    张鹏程; 陈克非

    2003-01-01

    Information security is a part of the core of computer field. This existing PKI system can not satisfy themore and more demand from people. Simple Public Key Infrastructure, SPKI, is new standard of public key certifi-cate, which can bring a simple but precise naming and authorization system for distributed computing environment.The base theory of SPKI is presented, and the brief analysis about its study hotspots and shortcomings are also shownin the paper.

  20. A new two-round dynamic authenticated contributory group key agreement protocol using elliptic curve Diffie–Hellman with privacy preserving public key infrastructure

    Indian Academy of Sciences (India)

    Vankamamidi S Naresh; Nistala V E S Murthy

    2015-10-01

    In this paper a new two-round authenticated contributory group key agreement based on Elliptic Curve Diffie–Hellman protocol with Privacy Preserving Public Key Infrastructure (PP-PKI) is introduced and is extended to a dynamic authenticated contributory group key agreement with join and leave protocols for dynamic groups. The proposed protocol provides such security attributes as forward secrecy, backward secrecy, and defense against man in the middle (MITM) and Unknown keyshare security attacks and also authentication along with privacy preserving attributes like anonymity, traceability and unlinkability. In the end, they are compared with other popular Diffie–Hellman and Elliptic Curve Diffie–Hellman based group key agreement protocols and the results are found to be satisfactory.

  1. A Review of Cryptographic Algorithms in Network Security

    Directory of Open Access Journals (Sweden)

    B.Nithya

    2016-02-01

    Full Text Available In the excellent growth of internet environment, there is a challenge to send data in secure. Security means sending information without any modification or hacking done by unauthorized users. The network security has the component of cryptography technique which acts like guard to the information. The general concept of cryptography is encryption and decryption. There are many cryptographic algorithms are used to send the information as cipher text which cannot be understand by the intruders. So experts have taken the existing algorithms to provide security over the network and they want to apply the benefits of those algorithms in the suitable places. First step of getting the help from algorithm is to be studied and compared their parameters. This paper presents a review that comparative study of algorithms taken by many authors.

  2. A Compendium Over Cloud Computing Cryptographic Algorithms and Security Issues

    Directory of Open Access Journals (Sweden)

    Neha Mishra

    2015-01-01

    Full Text Available Cloud computing is an emerging and revolutionary approach towards the computing and becoming more risk prone than ever before. It is an evolutionary approach of using resources and services on demand and as per need of consumers. Cloud computing providing a platform rose on the Internet for usage of IT services and flexible infrastructure to the consumers and business. Deployment and management of services or resources are maintained by the third party. Whereas there are innumerable advantages to approaching the cloud computing, it also contains various issues such as confidentiality, Integrity, Authenticity and Privacy. One of the prominent barrier to adopt the cloud computing is security. This paper comprises the elaborated study on various security issues allied to cloud computing are presented by consolidating literature reviews on cryptographic algorithms used for data security.

  3. Implimentation of Cryptographic Algorithm for GSM and UMTS Systems.

    Directory of Open Access Journals (Sweden)

    Alpesh R. Sankaliya

    2011-12-01

    Full Text Available Due to extremely high demand of mobile phones among people, over the years there has been a great demand for the support of various applications and security services. Cryptographic algorithms used by Mobile Subscribers to protect the privacy of their cellular voice and data communication. Ciphering provides the mean to regain control over privacy and authentication. A5/x are the encryption algorithms used in order to ensure privacy of conversations on mobile phones. A5/3 encryption algorithm used for 3G and GEA3 encryption algorithm used for GPRS. f8 is confidentiality algorithms developed by 3GPP used in UMTS System. The following paper is based on simulation of A5/3 and f8 algorithms.

  4. Analysis and Implementation of Cryptographic Hash Functions in Programmable Logic Devices

    Directory of Open Access Journals (Sweden)

    Tautvydas Brukštus

    2016-06-01

    Full Text Available In this day’s world, more and more focused on data pro-tection. For data protection using cryptographic science. It is also important for the safe storage of passwords for this uses a cryp-tographic hash function. In this article has been selected the SHA-256 cryptographic hash function to implement and explore, based on fact that it is now a popular and safe. SHA-256 cryp-tographic function did not find any theoretical gaps or conflict situations. Also SHA-256 cryptographic hash function used cryptographic currencies. Currently cryptographic currency is popular and their value is high. For the measurements have been chosen programmable logic integrated circuits as they less effi-ciency then ASIC. We chose Altera Corporation produced prog-rammable logic integrated circuits. Counting speed will be inves-tigated by three programmable logic integrated circuit. We will use programmable logic integrated circuits belong to the same family, but different generations. Each programmable logic integ-rated circuit made using different dimension technology. Choo-sing these programmable logic integrated circuits: EP3C16, EP4CE115 and 5CSEMA5F31. To compare calculations perfor-mances parameters are provided in the tables and graphs. Re-search show the calculation speed and stability of different prog-rammable logic circuits.

  5. Small private key MQPKS on an embedded microprocessor.

    Science.gov (United States)

    Seo, Hwajeong; Kim, Jihyun; Choi, Jongseok; Park, Taehwan; Liu, Zhe; Kim, Howon

    2014-03-19

    Multivariate quadratic (MQ) cryptography requires the use of long public and private keys to ensure a sufficient security level, but this is not favorable to embedded systems, which have limited system resources. Recently, various approaches to MQ cryptography using reduced public keys have been studied. As a result of this, at CHES2011 (Cryptographic Hardware and Embedded Systems, 2011), a small public key MQ scheme, was proposed, and its feasible implementation on an embedded microprocessor was reported at CHES2012. However, the implementation of a small private key MQ scheme was not reported. For efficient implementation, random number generators can contribute to reduce the key size, but the cost of using a random number generator is much more complex than computing MQ on modern microprocessors. Therefore, no feasible results have been reported on embedded microprocessors. In this paper, we propose a feasible implementation on embedded microprocessors for a small private key MQ scheme using a pseudo-random number generator and hash function based on a block-cipher exploiting a hardware Advanced Encryption Standard (AES) accelerator. To speed up the performance, we apply various implementation methods, including parallel computation, on-the-fly computation, optimized logarithm representation, vinegar monomials and assembly programming. The proposed method reduces the private key size by about 99.9% and boosts signature generation and verification by 5.78% and 12.19% than previous results in CHES2012.

  6. Performance Evaluation of Public Key Based Authentication in Future Mobile Communication Systems

    Directory of Open Access Journals (Sweden)

    Kambourakis Georgios

    2004-01-01

    Full Text Available While mobile hosts are evolving into full-IP enabled devices, there is a greater demand to provide a more flexible, reconfigurable, and scalable security mechanism in mobile communication systems beyond 3G (B3G. Work has already begun on such an “all-IP” end-to-end solution, commonly referred to as 4G systems. Fully fledged integration between heterogeneous networks, such as 2.5G, UMTS, WLAN, Bluetooth, and the Internet, demands fully compatible, time-tested, and reliable mechanisms to depend on. SSL protocol has proved its effectiveness in the wired Internet and it will probably be the most promising candidate for future wireless environments. In this paper, we discuss existing problems related to authentication and key agreement (AKA procedures, such as compromised authentication vectors attacks, as they appear in current 2/2.5G/3G mobile communication systems, and propose how SSL, combined with public key infrastructure (PKI elements, can be used to overcome these vulnerabilities. In this B3G environment, we perceive authentication as a service, which has to be performed at the higher protocol layers irrespective of the underlying network technology. Furthermore, we analyze the effectiveness of such a solution, based on measurements of a “prototype” implementation. Performance measurements indicate that SSL-based authentication can be possible in terms of service time in future wireless systems, while it can simultaneously provide both the necessary flexibility to network operators and a high level of confidence to end users.

  7. Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal

    DEFF Research Database (Denmark)

    Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne

    2016-01-01

    also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication. The objective is addressed in a literature review and a case study. The literature...... recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation...... review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed...

  8. Coordination between veterinary services and other relevant authorities: a key component of good public governance.

    Science.gov (United States)

    Bellemain, V

    2012-08-01

    Coordination between Veterinary Services and other relevant authorities is a key component of good public governance, especially for effective action and optimal management of available resources. The importance of good coordination is reflected in the World Organisation for Animal Health'Tool forthe Evaluation of Performance of Veterinary Services', which includes a critical competency on coordination. Many partners from technical, administrative and legal fields are involved. The degree of formalisation of coordination tends to depend on a country's level of organisation and development. Contingency plans against avian influenza led to breakthroughs in many countries in the mid-2000s. While interpersonal relationships remain vital, not everything should hinge on them. Organisation and management are critical to operational efficiency. The distribution of responsibilities needs to be defined clearly, avoiding duplication and areas of conflict. Lead authorities should be designated according to subject (Veterinary Services in animal health areas) and endowed with the necessary legitimacy. Lead authorities will be responsible for coordinating the drafting and updating of the relevant documents: agreements between authorities, contingency plans, standard operating procedures, etc.

  9. E-Visas Verification Schemes Based on Public-Key Infrastructure and Identity Based Encryption

    Directory of Open Access Journals (Sweden)

    Najlaa A. Abuadhmah

    2010-01-01

    Full Text Available Problem statement: Visa is a very important travelling document, which is an essential need at the point of entry of any country we are visiting. However an important document such as visa is still handled manually which affects the accuracy and efficiency of processing the visa. Work on e-visa is almost unexplored. Approach: This study provided a detailed description of a newly proposed e-visa verification system prototyped based on RFID technology. The core technology of the proposed e-visa verification system is based on Identity Based Encryption (IBE and Public Key Infrastructure (PKI. This research provided comparison between both methods in terms of processing time and application usability. Results: The result showed the e-visa verification system is highly flexible when implemented with IBE and on the other hand produces better processing speed when implemented with PKI. Conclusion: Therefore, it is believed that the proposed e-visa verification schemes are valuable security protocol for future study on e-visa.

  10. Optimal-Rate Coding Theorem For Adversarial Networks in the Public-Key Setting

    CERN Document Server

    Amir, Yair; Ostrovksy, Rafail

    2008-01-01

    In this paper, we establish an optimal-rate (interactive) coding theorem in the public-key setting for synchronous networks in the presence of a malicious poly-time adversary for dynamically changing networks. Namely, even if the majority of the nodes are controlled by a malicious adversary and the topology of the network is changing at each round, then as long as there is some path of non-corrupted nodes connecting the sender and receiver at each round (though this path may change at every round) we construct a protocol with bounded memory per processor that achieves optimal transfer rate and negligible decoding error. This protocol will transmit polynomially many messages of polynomial size with constant overhead per bit. We stress that our protocol assumes no knowledge of which nodes are corrupted nor which path is reliable at any round. Our interactive coding theorem states that our protocol cannot be affected in a meaningful way by any polynomial-time malicious adversary whose goal is to disrupt and dest...

  11. Stakeholders' perception of key performance indicators (KPIs of public-private partnership (PPP projects

    Directory of Open Access Journals (Sweden)

    Olabode Emmanuel Ogunsanmi

    2013-12-01

    Full Text Available The study investigates key performance indicators (KPIs that could improve performance of public-private partnership (PPP projects in Nigeria. The study objectives include a comparison of stakeholders’ perception on KPIs and to investigate if significant difference exists between stakeholders’ perceptions on most KPIs. A structured questionnaire was used to collect information from various respondents who were recently involved in PPP projects. Random sampling technique was used to select forty-five (45 respondents out of which thirty-one (31 responses were used for the data analysis. The results indicate that top KPIs for performance improvement are levels of design complexity and technological advancement, and return on investment. Stakeholders agree on most of the rankings of the KPIs. The general perception of stakeholders was similar on most KPIs except for a few divergent opinions. The study findings have an implication for policy and decision making such that stakeholders could pay special attention to the KPIs identified, that could improve construction project performance. Finally the study recommends further research to explore KPIs for other procurement options.

  12. Applications of Public Key Watermarking for Authentication of Job-Card in MGNREGA

    Directory of Open Access Journals (Sweden)

    Sunil Karforma

    2012-01-01

    Full Text Available Nowadays different state governments and central governments have taken initiative to successfully implement E-Governance in various areas of services applying Information and Communication Technology (ICT to provide better transparency, accuracy & security of its services to the citizens. In September, 2005, Parliament of India has passed the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA, to enhance livelihood security by giving at least 100 days of guaranteed wage employment in a financial year to every house-hold in rural India. E-Governance solutions helps to simplify complex manual activities and supports transparent wage payment through agencies like Bank and Post-Offices. In e-governance, information’s are exchanged between communicating parties via Internet and message may be changed, modified or destroyed by hackers during its transmission through Internet. So, information hiding is needed at the time of exchanging information via Internet. In this paper, we propose a tool, called Public-Key Watermarking algorithm, for integrity verification of Job-Card (JC issued to individual house-hold by state governments, so that the watermark is capable enough to detect any changes made to the Job-Card by malicious users and can also identify fraudulent wage payment.

  13. CRYPTOGRAPHIC MEANS OF INFORMATION PROTECTION AND PSYCHOLOGICAL COMFORT OF THE USERS OF COMPUTER INFORMATIONAL SYSTEMS

    Directory of Open Access Journals (Sweden)

    Yurii A. Kotsiuk

    2010-09-01

    Full Text Available The article checks up the existence of functional relation between the level of psychological comfort of the users of computer informational systems and their awareness/skills to use cryptographic means of information protection.

  14. Comparison Based Analysis of Different Cryptographic and Encryption Techniques Using Message Authentication Code (MAC) in Wireless Sensor Networks (WSN)

    CERN Document Server

    Rehman, Sadaqat Ur; Ahmad, Basharat; Yahya, Khawaja Muhammad; Ullah, Anees; Rehman, Obaid Ur

    2012-01-01

    Wireless Sensor Networks (WSN) are becoming popular day by day, however one of the main issue in WSN is its limited resources. We have to look to the resources to create Message Authentication Code (MAC) keeping in mind the feasibility of technique used for the sensor network at hand. This research work investigates different cryptographic techniques such as symmetric key cryptography and asymmetric key cryptography. Furthermore, it compares different encryption techniques such as stream cipher (RC4), block cipher (RC2, RC5, RC6 etc) and hashing techniques (MD2, MD4, MD5, SHA, SHA1 etc). The result of our work provides efficient techniques for communicating device, by selecting different comparison matrices i.e. energy consumption, processing time, memory and expenses that satisfies both the security and restricted resources in WSN environment to create MAC.

  15. Comparison Based Analysis of Different Cryptographic and Encryption Techniques Using Message Authentication Code (MAC in Wireless Sensor Networks (WSN

    Directory of Open Access Journals (Sweden)

    Sadaqat Ur Rehman

    2012-01-01

    Full Text Available Wireless Sensor Networks (WSN are becoming popular day by day, however one of the main issue in WSN is its limited resources. We have to look to the resources to create Message Authentication Code (MAC and need to choose a technique which is feasible for sensor networks. This research work investigates different cryptographic techniques such as symmetric key cryptography and asymmetric key cryptography, furthermore it compares different encryption techniques such as stream cipher (RC4, block cipher (RC2, RC5, RC6 etc and hashing techniques (MD2, MD4, MD5, SHA, SHA1 etc. The result of our work provides efficient techniques for communicator, by selecting different comparison matrices i.e. energy consumption, processing time, memory and expenses that satisfies both the security and restricted resources in WSN environment to create MAC

  16. Self-Organized Public-Key Management for Mobile Ad Hoc Networks Based on a Bidirectional Trust Model

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In traditional networks ,the authentication is performed by certificate authoritys(CA),which can't be built in distributed mobile Ad Hoc Networks however. In this paper, we propose a fully self-organized public key management based on bidirectional trust model without any centralized authority that allows users to generate their public-private key pairs, to issue certificates, and the trust relation spreads rationally according to the truly human relations. In contrast with the traditional self-organized public-key management, the average certificates paths get more short,the authentication passing rate gets more high and the most important is that the bidirectional trust based model satisfys the trust requirement of hosts better.

  17. Authenticated Key Agreement with Rekeying for Secured Body Sensor Networks

    Directory of Open Access Journals (Sweden)

    Kyngn Jung Kim

    2011-05-01

    Full Text Available Many medical systems are currently equipped with a large number of tiny, non-invasive sensors, located on, or close to, the patient’s body for health monitoring purposes. These groupings of sensors constitute a body sensor network (BSN. Key management is a fundamental service for medical BSN security. It provides and manages the cryptographic keys to enable essential security features such as confidentiality, integrity and authentication. Achieving key agreement in BSNs is a difficult task. Many key agreement schemes lack sensor addition, revocation, and rekeying properties, which are very important. Our proposed protocol circumvents these shortcomings by providing node rekeying properties, as well as node addition and revocation. It proposes a key distribution protocol based on public key cryptography—the RSA (Rivest, Shamir and Adleman algorithm, and the DHECC (Diffie-Hellman Elliptic Curve Cryptography algorithm. The proposed protocol does not trust individual sensors, and partially trusts the base station (hospital. Instead of loading full pair-wise keys into each node, after installation our protocol establishes pair-wise keys between nodes according to a specific routing algorithm. In this case, each node doesn’t have to share a key with all of its neighbors, only those involved in the routing path; this plays a key role in increasing the resiliency against node capture attacks and the network storage efficiency. Finally we evaluate our algorithm from the BSN security viewpoint and evaluate its performance in comparison with other proposals.

  18. Efficient Big Integer Multiplication and Squaring Algorithms for Cryptographic Applications

    Directory of Open Access Journals (Sweden)

    Shahram Jahani

    2014-01-01

    Full Text Available Public-key cryptosystems are broadly employed to provide security for digital information. Improving the efficiency of public-key cryptosystem through speeding up calculation and using fewer resources are among the main goals of cryptography research. In this paper, we introduce new symbols extracted from binary representation of integers called Big-ones. We present a modified version of the classical multiplication and squaring algorithms based on the Big-ones to improve the efficiency of big integer multiplication and squaring in number theory based cryptosystems. Compared to the adopted classical and Karatsuba multiplication algorithms for squaring, the proposed squaring algorithm is 2 to 3.7 and 7.9 to 2.5 times faster for squaring 32-bit and 8-Kbit numbers, respectively. The proposed multiplication algorithm is also 2.3 to 3.9 and 7 to 2.4 times faster for multiplying 32-bit and 8-Kbit numbers, respectively. The number theory based cryptosystems, which are operating in the range of 1-Kbit to 4-Kbit integers, are directly benefited from the proposed method since multiplication and squaring are the main operations in most of these systems.

  19. SHAMROCK: A Synthesizable High Assurance Cryptography and Key Management Coprocessor

    Science.gov (United States)

    2016-11-01

    cryptography; key management ; synthesizable. I. INTRODUCTION Modern cryptographic algorithms are designed with Kerckhoffs’ Principle in mind – that...LOCKMA supports good cryptography and key management practices . However, in general a software only solution is insufficient to guarantee the...1 SHAMROCK: A Synthesizable High Assurance Cryptography and Key Management Coprocessor David Whelihan, Michael Vai, Dan Utin, Roger Khazan, Karen

  20. Quantum cryptography beyond quantum key distribution

    NARCIS (Netherlands)

    A. Broadbent (Anne); C. Schaffner (Christian)

    2016-01-01

    textabstractQuantum cryptography is the art and science of exploiting quantum mechanical effects in order to perform cryptographic tasks. While the most well-known example of this discipline is quantum key distribution (QKD), there exist many other applications such as quantum money, randomness

  1. Quantum cryptography beyond quantum key distribution

    NARCIS (Netherlands)

    Broadbent, A.; Schaffner, C.

    2016-01-01

    Quantum cryptography is the art and science of exploiting quantum mechanical effects in order to perform cryptographic tasks. While the most well-known example of this discipline is quantum key distribution (QKD), there exist many other applications such as quantum money, randomness generation,

  2. Quantum cryptography beyond quantum key distribution

    NARCIS (Netherlands)

    Broadbent, A.; Schaffner, C.

    2016-01-01

    Quantum cryptography is the art and science of exploiting quantum mechanical effects in order to perform cryptographic tasks. While the most well-known example of this discipline is quantum key distribution (QKD), there exist many other applications such as quantum money, randomness generation, secu

  3. A Market Analysis of Publications, Trade Conferences, and Key Events for Fleet Readiness Center Southwest

    Science.gov (United States)

    2007-12-01

    Win and Keep Big Customers. Austin: Bard Press, 2005. Kotler , Philip and Kevin Lane Keller. Marketing Management. Upper Saddle River, NJ...stimulate awareness and demand with little or no cost. Kotler and Keller describe public relations and publicity as “a variety of programs designed to...broadcast media to promote something.”13 Kotler and Keller also argue that there is an appeal to the use of public relations and publicity that is based

  4. Certificateless Multi-receiver Signcryption Scheme Based on Multivariate Public Key Cryptography%基于多变量公钥密码体制的无证书多接收者签密体制

    Institute of Scientific and Technical Information of China (English)

    李慧贤; 陈绪宝; 庞辽军; 王育民

    2012-01-01

    针对基于身份的多接收者签密方案不能抵抗量子攻击以及存在的密钥托管问题,基于多变量公钥密码体制,提出一个多接收者模型下的无证书签密方案.新方案不仅避免了基于身份密码体制的密钥托管问题,而且继承了多变量公钥密码体制的优势,实现了“抗量子攻击”的高安全性.与现有方案相比,新方案无需双线性对操作,具有更少的计算量,更高的计算效率,适用于智能卡等计算能力较小的终端设备.最后,在随机预言模型下,给出了该文方案基于MQ困难问题假设和IP困难问题假设的安全性证明.分析表明,该文方案具有不可否认性、前向安全性、后向安全性、保护接收者隐私等安全属性.%Aiming at the vulnerability under quantum attacks and the inherent key escrow problem of the existing ID-based multi-receiver signcryption schemes, we propose an efficient certificateless multi-receiver signcryption scheme (CLMSC), which is based on the multivariate public key cryptography (MPKC). The new scheme can not only avoid the inherent key escrow problem in the identity-based cryptographic system,but also have the advantage of MPKC, that is, it can withstand the quantum attack. The proposed scheme does not require any pairing operations in signcrypting a message for any number of receivers. Therefore, compared with the existing signcryption schemes, the proposed scheme is more efficient, and thus it is suitable for terminals which have lower computation capacity like smart card. Finally, we prove its semantic security under the hardness of Multivariate Quadratic (MQ) problem and its unforgeability under the Isomorphism of Polynomials (IP) assumption in the random oracle model respectively. The proposed scheme also has the security properties of non-repudiation, forward security, backward security and the recipient privacy protection.

  5. Key challenges of offshore wind power: Three essays addressing public acceptance, stakeholder conflict, and wildlife impacts

    Science.gov (United States)

    Bates, Alison Waterbury

    been proposed. The essay examines how the public considers the societal tradeoffs that are made to develop small-scale, in-view demonstration wind projects instead of larger facilities farther offshore. Results indicate that a strong majority of the public supports near-shore demonstration wind projects in both states. Primary reasons for support include benefits to wildlife, cost of electricity, and job creation, while the primary reasons for opposition include wildlife impacts, aesthetics, tourism, and user conflicts. These factors differ between coastal Delaware and greater Atlantic City and highlight the importance of local, community engagement in the early stages of development. The second essay examines the interaction of a new proposed use of the ocean---offshore wind---and a key existing ocean user group---commercial fishers. A key component of offshore wind planning includes consideration of existing uses of the marine environment in order to optimally site wind projects while minimizing conflicts. Commercial fisheries comprise an important stakeholder group, and may be one of the most impacted stakeholders from offshore renewable energy development. Concern of the fishing industry stems from possible interference with productive fishing grounds and access within wind developments resulting in costs from increased effort or reduction in catch. Success of offshore wind development may in part depend on the acceptance of commercial fishers, who are concerned about loss of access to fishing grounds. Using a quantitative, marine spatial planning approach in the siting of offshore wind projects with respect to commercial fishing in the mid-Atlantic, U.S., this essay develops a spatially explicit representation of potential conflicts and compatibilities between these two industries in the mid-Atlantic region of the United States. Areas that are highly valuable to the wind industry are determined through a spatial suitability model using variable cost per unit

  6. The Homomorphic Key Agreement

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    There are various challenges that are faced in group communication, so it is necessary to ensure session key. Key agreement is the fundamental cryptographic primitive for establishing a secure communication. It is a process of computing a shared secret contributed by two or more entities such that no single node can predetermine the resulting value. An authenticated key agreement is attained by combining the key agreement protocol with digital signatures. After a brief introduction to existing key agreement in group communication, Making use of the additive-multiplicative homomorphism in the integer ring defined by Sander and Tschudin: A new protocols, called the homomorphism key agreement, was designed, which can be self-contributory, robust, scalable and applicable in group communication.

  7. Authenticated group Diffie-Hellman key exchange: theory and practice

    Energy Technology Data Exchange (ETDEWEB)

    Chevassut, Olivier [Catholic Univ. of Louvain, Louvain-la-Neuve (Belgium)

    2002-10-01

    Authenticated two-party Diffie-Hellman key exchange allows two principals A and B, communicating over a public network, and each holding a pair of matching public/private keys to agree on a session key. Protocols designed to deal with this problem ensure A (B resp.)that no other principals aside from B (A resp.) can learn any information about this value. These protocols additionally often ensure A and B that their respective partner has actually computed the shared secret value. A natural extension to the above cryptographic protocol problem is to consider a pool of principals agreeing on a session key. Over the years several papers have extended the two-party Diffie-Hellman key exchange to the multi-party setting but no formal treatments were carried out till recently. In light of recent developments in the formalization of the authenticated two-party Diffie-Hellman key exchange we have in this thesis laid out the authenticated group Diffie-Hellman key exchange on firmer foundations.

  8. Cryptographically supported NFC tags in medication for better inpatient safety.

    Science.gov (United States)

    Özcanhan, Mehmet Hilal; Dalkılıç, Gökhan; Utku, Semih

    2014-08-01

    Reliable sources report that errors in drug administration are increasing the number of harmed or killed inpatients, during healthcare. This development is in contradiction to patient safety norms. A correctly designed hospital-wide ubiquitous system, using advanced inpatient identification and matching techniques, should provide correct medicine and dosage at the right time. Researchers are still making grouping proof protocol proposals based on the EPC Global Class 1 Generation 2 ver. 1.2 standard tags, for drug administration. Analyses show that such protocols make medication unsecure and hence fail to guarantee inpatient safety. Thus, the original goal of patient safety still remains. In this paper, a very recent proposal (EKATE) upgraded by a cryptographic function is shown to fall short of expectations. Then, an alternative proposal IMS-NFC which uses a more suitable and newer technology; namely Near Field Communication (NFC), is described. The proposed protocol has the additional support of stronger security primitives and it is compliant to ISO communication and security standards. Unlike previous works, the proposal is a complete ubiquitous system that guarantees full patient safety; and it is based on off-the-shelf, new technology products available in every corner of the world. To prove the claims the performance, cost, security and scope of IMS-NFC are compared with previous proposals. Evaluation shows that the proposed system has stronger security, increased patient safety and equal efficiency, at little extra cost.

  9. Preventing Real-Time Packet Classification Using Cryptographic Primitives

    Directory of Open Access Journals (Sweden)

    N.Vasumathi

    2014-03-01

    Full Text Available Jamming attacks are especially harmful when ensuring the dependability of wireless communication. Typically, jamming has been addressed under an external threat model. Adversaries with internal knowledge of protocol specifications and network secrets can launch low-effort jamming attacks that are difficult to detect and counter. The problem of selective jamming attacks in wireless networks is addressed in this work. In these attacks, the adversary is active only for a short period of time, specifically targeting messages of high importance. The advantages of selective jamming in terms of network performance degradation and adversary effort is illustrated by presenting two case studies; one is selective attack on TCP and another is on routing. The selective jamming attacks can be launched by performing real-time packet classification at the physical layer. To avoid these attacks, four schemes are developed such as All Or Nothing Transformation-Hiding Scheme (AONT-HS - pseudo message is added with message before transformation and encryption, Strong Hiding Commitment Scheme(SHCS - off-the-shelf symmetric encryption is done, Puzzle Based Hiding Scheme(PBHS- time lock and hash puzzle and Nonce based Authenticated Encryption Scheme(N-AES-Nonce is used for encryption, that prevent real-time packet classification by combining cryptographic primitives with physical-layer attributes.

  10. An Investigation of the National School Board Association Key Work Standards for Public Policy Leadership and School Board Chair Performance

    Science.gov (United States)

    Quarles, Roger C.

    2011-01-01

    This multiple case qualitative study addressed the National School Board Association's (NSBA) Key Work standards for public policy leadership by local school boards, and how three elite school board chairs understood and implemented those standards. Elite board chair status was defined by experience, training, and peer recognition. The study…

  11. An Investigation of the National School Board Association Key Work Standards for Public Policy Leadership and School Board Chair Performance

    Science.gov (United States)

    Quarles, Roger C.

    2011-01-01

    This multiple case qualitative study addressed the National School Board Association's (NSBA) Key Work standards for public policy leadership by local school boards, and how three elite school board chairs understood and implemented those standards. Elite board chair status was defined by experience, training, and peer recognition. The study…

  12. Efficient Identity Based Public Verifiable Signcryption Scheme

    CERN Document Server

    Kushwah, Prashant

    2011-01-01

    Signcryption is a cryptographic primitive which performs encryption and signature in a single logical step. In conventional signcryption only receiver of the signcrypted text can verify the authenticity of the origin i.e. signature of the sender on the message after decrypting the cipher text. In public verifiable signcryption scheme anyone can verify the authenticity of the origin who can access the signcrypted text i.e. signature of the sender on the cipher text. Public verifiable signcryption scheme in which the receiver can convince a third party, by providing additional information other than his private key along with the signcryption is called third party verifiable signcryption schemes. In this paper we proposed an efficient identity based public verifiable signcryption scheme with third party verification and proved its security in the random oracle model.

  13. Public health ethics: key concepts and issues in policy and practice

    National Research Council Canada - National Science Library

    Dawson, Angus

    2011-01-01

    .... Topics covered include the nature of public health ethics, the concepts of disease and prevention, risk and precaution, health inequalities and justice, screening, vaccination and disease control...

  14. Best practices for interacting with the public about wildland fire: Key findings from interviews

    Science.gov (United States)

    Daniel Berkman

    2012-01-01

    Interviews were conducted with public information and line officers about wildland fire communications with the public. The goal of these interviews was to determine the best practices and most useful content and format for an annotated bibliography about external wildland fire communications, i.e., does the current literature reviewed address the issues of greatest...

  15. Provably-Secure Authenticated Group Diffie-Hellman KeyExchange

    Energy Technology Data Exchange (ETDEWEB)

    Bresson, Emmanuel; Chevassut, Olivier; Pointcheval, David

    2007-01-01

    Authenticated key exchange protocols allow two participantsA and B, communicating over a public network and each holding anauthentication means, to exchange a shared secret value. Methods designedto deal with this cryptographic problem ensure A (resp. B) that no otherparticipants aside from B (resp. A) can learn any information about theagreed value, and often also ensure A and B that their respective partnerhas actually computed this value. A natural extension to thiscryptographic method is to consider a pool of participants exchanging ashared secret value and to provide a formal treatment for it. Startingfrom the famous 2-party Diffie-Hellman (DH) key exchange protocol, andfrom its authenticated variants, security experts have extended it to themulti-party setting for over a decade and completed a formal analysis inthe framework of modern cryptography in the past few years. The presentpaper synthesizes this body of work on the provably-secure authenticatedgroup DH key exchange.

  16. Key issues of public relations of Europe: Findings from the European Communication Monitor 2007-2014

    Directory of Open Access Journals (Sweden)

    Dejan Vercic

    2014-10-01

    Full Text Available European Communication Monitor is the largest longitudinal research project in public relations practice in the world. Data collected annually from 2007 to 2014 show that practitioners perceive five issues as the most important for their work: linking business strategy and communication, coping with the digital evolution and social web, building and maintaining trust, dealing with the demand for more transparency and active audiences, and dealing with the speed and volume of information flow. Perception of the importance of various issues for the practice of public relations is largely dependent on the gender, geography (division between Northern and Western vs. Southern and Eastern Europe, and sector in which a practitioner works (corporate, government, NGO or agency. While gender and sectorial differences studied in academic public relations literature, divisions in public relations practice between North-Western and South-Eastern Europe are largely ignored.

  17. Building Interdisciplinary Research Capacity: a Key Challenge for Ecological Approaches in Public Health

    Directory of Open Access Journals (Sweden)

    Lindsay P. Galway

    2016-06-01

    Full Text Available The shortcomings of public health research informed by reductionist and fragmented biomedical approaches and the emergence of wicked problems are fueling a renewed interest in ecological approaches in public health. Despite the central role of interdisciplinarity in the context of ecological approaches in public health research, inadequate attention has been given to the specific challenge of doing interdisciplinary research in practice. As a result, important knowledge gaps exist with regards to the practice of interdisciplinary research. We argue that explicit attention towards the challenge of doing interdisciplinary research is critical in order to effectively apply ecological approaches to public health issues. This paper draws on our experiences developing and conducting an interdisciplinary research project exploring the links among climate change, water, and health to highlight five specific insights which we see as relevant to building capacity for interdisciplinary research specifically, and which have particular relevance to addressing the integrative challenges demanded by ecological approaches to address public health issues. These lessons include: (i the need for frameworks that facilitate integration; (ii emphasize learning-by-doing; (iii the benefits of examining issues at multiple scales; (iv make the implicit, explicit; and (v the need for reflective practice. By synthesizing and sharing experiences gained by engaging in interdisciplinary inquiries using an ecological approach, this paper responds to a growing need to build interdisciplinary research capacity as a means for advancing the ecological public health agenda more broadly.

  18. Key Management Building Blocks for Wireless Sensor Networks

    NARCIS (Netherlands)

    Law, Y.W.; Doumen, J.M.; Palaniswami, M.

    2007-01-01

    Cryptography is the means to ensure data confidentiality, integrity and authentication in wireless sensor networks (WSNs). To use cryptography effectively however, the cryptographic keys need to be managed properly. First of all, the necessary keys need to be distributed to the nodes before the node

  19. Key Management Building Blocks for Wireless Sensor Networks

    NARCIS (Netherlands)

    Law, Y.W.; Doumen, J.M.; Palaniswami, M

    2007-01-01

    Cryptography is the means to ensure data confidentiality, integrity and authentication in wireless sensor networks (WSNs). To use cryptography effectively however, the cryptographic keys need to be managed properly. First of all, the necessary keys need to be distributed to the nodes before the

  20. Civic participation and public spaces: a key factor for sustainable tourism in historic cities

    Directory of Open Access Journals (Sweden)

    Martin van der Zwan

    2016-06-01

    Full Text Available Attractive public spaces are crucial for tourism. After all, most tourists that visit a city, experience it by foot and increasingly by bicycle. Public spaces have to meet a few minimum requirements. If not, tourists will feel uncomfortable. For instance; a lot of rubbish and graffiti, worn out and damaged street furniture can cause a feeling of unsafety. Attractive public spaces are the ones that invite tourists to stay a bit longer than strictly necessary and sit down and relax. Some of these spaces are quit and green, others more vibrant, well dimensioned and furbished. In this paper I describe a method for defining and measuring the quality of public space and also for predicting the conclusion tourists may draw based on this; “will I revisit this place or not ?” In some cities inhabitants, local shop owners and local institutions voluntarily take the initiative to upgrade the quality of public spaces or even act as ‘city hosts’ to welcome visitors. These kinds of civic participation help to provide the unique experience many tourists are looking for.

  1. METHOD OF GENERATING COMMON CRYPTOGRAPHIC KEYS FOR LOOSLY COINCIDENT BINARY SEQUENCES

    Directory of Open Access Journals (Sweden)

    V. L. Pivovarov

    2016-01-01

    Full Text Available The method of forming a common secret binary sequence between using an open communication channel is considered. The method is not based on common unidirectional functions and results in iterative elimination of distinct bits in the initial binary sequences with a certain percentage of mismatches, intentionally made by subscribers themselves. The cryptanalysis technique of this method based on the use of the deviation of aprior distribution of probabilities of inverting bits in the original binary sequences of subscribers from uniform distribution is proposed. Part of the bits in the final secret sequence can be identified accurately enough.

  2. Automatic Inference of Cryptographic Key Length Based on Analysis of Proof Tightness

    Science.gov (United States)

    2016-06-01

    the general number field sieve (GNFS) algorithm [23]. 16 CHAPTER 4: Concept of Operations and Design In this chapter we discuss concept of operations...maintaining and automatically reasoning about these expanded attack trees. We provide a software tool that utilizes machine -readable proof and attack metadata...for maintaining and automatically reasoning about these expanded attack trees. We provide a software tool that utilizes machine -readable proof and

  3. Finding your voice: key elements to consider when writing for publication.

    Science.gov (United States)

    Wollin, Judy Ann; Fairweather, Carrie Therese

    The dissemination of nursing knowledge rests on optimizing the accessibility of such knowledge among nurses and all other healthcare professionals. Nursing publications of all types, including research, case studies, reports, literature reviews, clinical audits, reflections on practice and letters to the editor, are important mechanisms for sharing knowledge and experience. Nurses need to publish their knowledge and experiences to inform and reflect on nursing practice. Barriers to writing for publication include inexperience and lack of know how. This article provides guidance for the novice writer.

  4. Abstraction for Epistemic Model Checking of Dining Cryptographers-based Protocols

    CERN Document Server

    Al-Bataineh, Omar I

    2010-01-01

    The paper describes an abstraction for protocols that are based on multiple rounds of Chaum's Dining Cryptographers protocol. It is proved that the abstraction preserves a rich class of specifications in the logic of knowledge, including specifications describing what an agent knows about other agents' knowledge. This result can be used to optimize model checking of Dining Cryptographers-based protocols, and applied within a methodology for knowledge-based program implementation and verification. Some case studies of such an application are given, for a protocol that uses the Dining Cryptographers protocol as a primitive in an anonymous broadcast system. Performance results are given for model checking knowledge-based specifications in the concrete and abstract models of this protocol, and some new conclusions about the protocol are derived.

  5. Public Key Infrastructure (PKI) And Virtual Private Network (VPN) Compared Using An Utility Function And The Analytic Hierarchy Process (AHP)

    OpenAIRE

    Wagner, Edward Dishman

    2002-01-01

    This paper compares two technologies, Public Key Infrastructure (PKI) and Virtual Private Network (VPN). PKI and VPN are two approaches currently in use to resolve the problem of securing data in computer networks. Making this comparison difficult is the lack of available data. Additionally, an organization will make their decision based on circumstances unique to their information security needs. Therefore, this paper will illustrate a method using a utility function and the Analytic Hie...

  6. 基于共享密钥的RFID认证协议%RFID Authentication Protocol Based on Public Crypto Key

    Institute of Scientific and Technical Information of China (English)

    冯军; 潘郁

    2012-01-01

    Aiming at the problems presently existing in security of the radio frequency identification (RFID) technology, the RFID security protocol is designed by adopting Hash function and public crypto key. The security and privacy issues existing in practical applications of RFID are analyzed, and the RFID authentication protocol based on NTRU public key crypto graphy system and Hash function is proposed. By adopting NTRU public key crypto system, the shared key is generated, and the shared key is conducted with Hash operation by using Hash function, and the information security of RFID is guaranteed. The theoretical analysis shows that this protocol can effectively protect the information from the secure attacks, e.g. , divulging, disguising and position tracking, etc.%针对目前无线射频识别(RHD)技术在安全性方面存在的问题,采用散列函数和共享密钥设计了RFID安全协议.分析了RFID在实际应用中存在的安全和隐私问题,提出了一种基于数论研究单元(NTRU)公钥密码系统和Hashh函数的RFID认证协议.该协议利用NTRU公钥密码系统产生系统的共享公钥,并运用Hash函数对共享公钥进行Hash运算,保证了RFID系统信息安全性.理论分析表明,该协议能有效地防止消息泄漏、伪装、定位跟踪等安全攻击.

  7. Interviewing Key Informants: Strategic Planning for a Global Public Health Management Program

    Science.gov (United States)

    Kun, Karen E.; Kassim, Anisa; Howze, Elizabeth; MacDonald, Goldie

    2013-01-01

    The Centers for Disease Control and Prevention's Sustainable Management Development Program (SMDP) partners with low- and middle-resource countries to develop management capacity so that effective global public health programs can be implemented and better health outcomes can be achieved. The program's impact however, was variable. Hence, there…

  8. Key issues of public relations of Europe: findings from the European Communication Monitor 2007-2014

    NARCIS (Netherlands)

    Verčič, D.; Verhoeven, P.; Zerfass, A.

    2014-01-01

    European Communication Monitor is the largest longitudinal research project in public relations practice in the world. Data collected annually from 2007 to 2014 show that practitioners perceive five issues as the most important for their work: linking business strategy and communication, coping with

  9. Key issues of public relations of Europe: findings from the European Communication Monitor 2007-2014

    NARCIS (Netherlands)

    Verčič, D.; Verhoeven, P.; Zerfass, A.

    2014-01-01

    European Communication Monitor is the largest longitudinal research project in public relations practice in the world. Data collected annually from 2007 to 2014 show that practitioners perceive five issues as the most important for their work: linking business strategy and communication, coping with

  10. The REESSE2+ Public-key Encryption Scheme - Another Application of the Lever Function and its Connotation

    CERN Document Server

    Su, Shenghui; Hu, Jun

    2008-01-01

    This paper gives the definitions of a nonnormal super-increasing sequence and a nonnormal subset sum separately, proves the two properties of a nonnormal super-increasing sequence, and proposes the REESSE2+ public-key encryption scheme which includes the three algorithms for key generation, encryption and decryption. The paper discusses the necessity and sufficiency of the lever function for preventing the Shamir extremum attack, analyzes the security of REESSE2+ against extracting a private key from a public key through the exhaustive search, recovering a plaintext from a ciphertext plus a knapsack of high density through the LLL lattice basis reduction method, and heuristically obtaining a plaintext through the meet-in-the-middle attack or the adaptive-chosen-ciphertext attack. The authors evaluate the time complexity of the REESSE2+ algorithms, compare REESSE2+ with ECC and NTRU, and find that the encryption speed of REESSE2+ is ten thousand times faster than ECC and NTRU bearing the matchable security, an...

  11. Performance Impacts of Lower-Layer Cryptographic Methods in Mobile Wireless Ad Hoc Networks

    Energy Technology Data Exchange (ETDEWEB)

    VAN LEEUWEN, BRIAN P.; TORGERSON, MARK D.

    2002-10-01

    In high consequence systems, all layers of the protocol stack need security features. If network and data-link layer control messages are not secured, a network may be open to adversarial manipulation. The open nature of the wireless channel makes mobile wireless mobile ad hoc networks (MANETs) especially vulnerable to control plane manipulation. The objective of this research is to investigate MANET performance issues when cryptographic processing delays are applied at the data-link layer. The results of analysis are combined with modeling and simulation experiments to show that network performance in MANETs is highly sensitive to the cryptographic overhead.

  12. Public-private relationships in biobanking: a still underestimated key component of open innovation.

    Science.gov (United States)

    Hofman, Paul; Bréchot, Christian; Zatloukal, Kurt; Dagher, Georges; Clément, Bruno

    2014-01-01

    Access to human bioresources is essential to the understanding of human diseases and to the discovery of new biomarkers aimed at improving the diagnosis, prognosis, and the predictive response of patients to treatments. The use of biospecimens is strictly controlled by ethical assessment, which complies with the laws of the country. These laws regulate the partnerships between the biobanks and industrial actors. However, private-public partnerships (PPP) can be limiting for several reasons, which can hamper the discovery of new biological tests and new active molecules targeted to human diseases. The bottlenecks and roadblocks in establishing these partnerships include: poor organization of the biobank in setting up PPP, evaluation of the cost of human samples, the absence of experience on the public side in setting up contracts with industry, and the fact that public and private partners may not share the same objectives. However, it is critical, in particular for academic biobanks, to establish strong PPP to accelerate translational research for the benefits of patients, and to allow the sustainability of the biobank. The purpose of this review is to discuss the main bottlenecks and roadblocks that can hamper the establishment of PPP based on solid and trusting relationships.

  13. Why sustainable population growth is a key to climate change and public health equity.

    Science.gov (United States)

    Howat, Peter; Stoneham, Melissa

    2011-12-01

    Australia's population could reach 42 million by 2050. This rapid population growth, if unabated, will have significant social, public health and environmental implications. On the one hand, it is a major driver of climate change and environmental degradation; on the other it is likely to be a major contributor to growing social and health issues including a decline in quality of life for many residents. Disadvantaged and vulnerable groups will be most affected. The environmental, social and health-related issues include: pressure on the limited arable land in Australia; increased volumes of industrial and domestic waste; inadequate essential services; traffic congestion; lack of affordable housing; declining mental health; increased obesity problems; and inadequate aged care services. Many of these factors are related to the aggravation of climate change and health inequities. It is critical that the Australian Government develops a sustainable population plan with stabilisation of population growth as an option. The plan needs to ensure adequate hospitals and healthcare services, education facilities, road infrastructure, sustainable transport options, water quality and quantity, utilities and other amenities that are already severely overburdened in Australian cities. There is a need for a guarantee that affordable housing will be available and priority be given to training young people and Indigenous people for employment. This paper presents evidence to support the need for the stabilisation of population growth as one of the most significant measures to control climate change as well as to improve public health equity.

  14. [Key measures for developing palliative care from a public health perspective. Initial results from a three-round Delphi study].

    Science.gov (United States)

    Behmann, M; Jünger, S; Radbruch, L; Schneider, N

    2011-05-01

    Recently, six key targets for public health initiatives to improve palliative care in Germany were defined. This article reports the initial results of a follow-up study aiming at developing concrete measures to achieve these targets. We carried out a three-round Delphi study with stakeholders acting on the meso- and macro-levels of the German healthcare system (e.g., representatives of patient organizations, health insurance funds, politics, medical and nursing associations). In the first Delphi round, participants proposed measures to achieve the six key targets using free-text answers. The answers were analyzed with a qualitative-descriptive approach. In total, 107 stakeholders responded to the first Delphi round. After data reduction, 37 measures were extracted and grouped into six major categories: family carers, qualification, quality, public relations, services, and coordination. The range of measures on the different levels of policy, health care, and education presents a substantiated basis for the elaboration of targeted public health action plans to improve palliative care. Prioritization of measures in the second and third Delphi rounds will provide empirical support for decision making.

  15. A Novel Method for Generating Encryption Keys

    Directory of Open Access Journals (Sweden)

    Dascalescu Ana Cristina

    2009-12-01

    Full Text Available The development of the informational society, which has led to an impressive growth of the information volume circulating in the computer networks, has accelerated the evolution and especially the use of modern cryptography instruments. Today, the commercial products use standard cryptographic libraries that implement certified and tested cryptographic algorithms. Instead, the fragility ofencryption algorithms is given by compositional operations like key handling or key generation. In this sense, the article proposes an innovative method to generate pseudorandom numbers which can be used for the construction of secure stream encryption keys. The proposed method is based on the mathematical complements based on the algebra of the finite fields and uses a particularized structure of the linear feedback shift registers.

  16. Public Policies for ICT Update In Business: Some Key Indicators for Spain in the European Area

    Directory of Open Access Journals (Sweden)

    José Luis Vázquez

    2013-08-01

    Full Text Available Purpose—Based on the new face of business in the twenty first century, this general review is aimed at analyzing the use of information and communication technologies (ICT as social technologies by Spanish enterprises in the European context, as a result of recent policy frameworks set at communitarian and national levels.Design/methodology/approach—The paper reviews the guidelines marked by European common policies with regards to ICT update in business, just as the translation of such standards in the Spanish area. From this framework, implications of ICT adoption in the social relationships with consumers, employees, business partners and public authorities are analyzed by providing some figures in the Spanish context in comparison with the European average.Findings—The analysis supports a positive effect of national policies on Spanish enterprises’ use of social technologies in the interactions with their internal and external stakeholders, while some differences can be reported attending size and sector criteria. In this respect, ICT penetration seems to be widespread in Spanish enterprises longer than ten employees, specially within informatics, telecommunications and audiovisuals, whereas automation of interactions is moderated in micro-enterprises in the manufacture, building, retailing, and transportation sectors.Research limitations/implications—The paper offers a general overview of the use of ICT as social technologies in Spanish enterprises based on public reports. However, further research should be oriented to analyze more in deep the impact of public policies on ICT adoption and usage in business, by explaining their determining factors and comparing different clusters of counties and major regions of the world.Practical implications—The analysis reported point to the need of reinforcing the Spanish positioning in the ICT European sector in the long term. In this sense, future policy measures should be devoted to

  17. Public Policies for ICT Update In Business: Some Key Indicators for Spain in the European Area

    Directory of Open Access Journals (Sweden)

    Ana Lanero

    2011-08-01

    Full Text Available Purpose—Based on the new face of business in the twenty first century, this general review is aimed at analyzing the use of information and communication technologies (ICT as social technologies by Spanish enterprises in the European context, as a result of recent policy frameworks set at communitarian and national levels. Design/methodology/approach—The paper reviews the guidelines marked by European common policies with regards to ICT update in business, just as the translation of such standards in the Spanish area. From this framework, implications of ICT adoption in the social relationships with consumers, employees, business partners and public authorities are analyzed by providing some figures in the Spanish context in comparison with the European average.Findings—The analysis supports a positive effect of national policies on Spanish enterprises’ use of social technologies in the interactions with their internal and external stakeholders, while some differences can be reported attending size and sector criteria. In this respect, ICT penetration seems to be widespread in Spanish enterprises longer than ten employees, specially within informatics, telecommunications and audiovisuals, whereas automation of interactions is moderated in micro-enterprises in the manufacture, building, retailing, and transportation sectors.Research limitations/implications—The paper offers a general overview of the use of ICT as social technologies in Spanish enterprises based on public reports. However, further research should be oriented to analyze more in deep the impact of public policies on ICT adoption and usage in business, by explaining their determining factors and comparing different clusters of counties and major regions of the world.Practical implications—The analysis reported point to the need of reinforcing the Spanish positioning in the ICT European sector in the long term. In this sense, future policy measures should be devoted to

  18. Analysis of cryptographic mechanisms used in ransomware CryptXXX v3

    Directory of Open Access Journals (Sweden)

    Michał Glet

    2016-12-01

    Full Text Available The main purpose of this paper was to analysis how malicious software is using cryptographic mechanisms. Reverse engineering were applied in order to discover mechanisms used in ransomware CryptXXX v3. At the end were given some useful advices how to improve CryptXXX.[b]Keyword:[/b] ransomware, software engineering, reverse engineering, RC4, RSA, malicious software

  19. Type-Based Automated Verification of Authenticity in Asymmetric Cryptographic Protocols

    DEFF Research Database (Denmark)

    Dahl, Morten; Kobayashi, Naoki; Sun, Yunde

    2011-01-01

    Gordon and Jeffrey developed a type system for verification of asymmetric and symmetric cryptographic protocols. We propose a modified version of Gordon and Jeffrey's type system and develop a type inference algorithm for it, so that protocols can be verified automatically as they are, without any...

  20. Construction of cryptographic information protection in automated control systems for rapid reaction military forces

    Directory of Open Access Journals (Sweden)

    Sergey Petrovich Evseev

    2012-04-01

    Full Text Available New approaches to realizations of military operations are analyzed. The main factors that directly affect the construction and operation of information security subsystems in prospective automated command and control military systems are described. Possible ways of the construction of cryptographic subsystems of information protection in automated operation management systems for united military force groups are investigated.

  1. Analysis of cryptographic mechanisms used in ransomware CryptXXX v3

    OpenAIRE

    Michał Glet

    2016-01-01

    The main purpose of this paper was to analysis how malicious software is using cryptographic mechanisms. Reverse engineering were applied in order to discover mechanisms used in ransomware CryptXXX v3. At the end were given some useful advices how to improve CryptXXX.[b]Keyword:[/b] ransomware, software engineering, reverse engineering, RC4, RSA, malicious software

  2. On the Ergodic Secret-Key Agreement over Spatially Correlated Multiple-Antenna Channels with Public Discussion

    KAUST Repository

    Zorgui, Marwen

    2015-09-28

    We consider secret-key agreement with public discussion over multiple-input multiple-output (MIMO) Rayleigh fast-fading channels under correlated environment. We assume that transmit, legitimate receiver and eavesdropper antennas are correlated. The legitimate receiver and the eavesdropper are assumed to have perfect channel knowledge while the transmitter has only knowledge of the correlation matrices. First, we derive the expression of the secret-key capacity under the considered setup. We prove that the optimal transmit strategy achieving the secret-key capacity consists in transmitting independent Gaussian signals along the eingenvectors of the transmit correlation matrix. The powers allocated to each channel mode are determined as the solution to a numerical optimization problem. A necessary and sufficient condition for beamforming (i.e., transmitting along the strongest channel mode) to be capacity-achieving is derived. Moreover, we analyze the impact of correlation matrices on the system performance. Finally, we study the system’s performance in the two extreme power regimes. In the high-power regime, we provide closed-form expressions of the gain/loss due to correlation. In the low signal-to-noise ratio (SNR) regime, we investigate the energy efficiency of the system by determining the minimum energy required for sharing a secret-key bit and the wideband slope while highlighting the impact of correlation matrices.

  3. Key aspects of a Flemish system to safeguard public health interests in case of chemical release incidents.

    Science.gov (United States)

    Smolders, Roel; Colles, Ann; Cornelis, Christa; Van Holderbeke, Mirja; Chovanova, Hana; Wildemeersch, Dirk; Mampaey, Maja; Van Campenhout, Karen

    2014-12-15

    Although well-established protocols are available for emergency services and first-responders in case of chemical release incidents, a well-developed system to monitor and safeguard public health was, until recently, lacking in Flanders. We therefore developed a decision support system (DSS) to aid public health officials in identifying the appropriate actions in case of incidents. Although the DSS includes human biomonitoring as one of its key instruments, it also goes well beyond this instrument alone. Also other, complementary, approaches that focus more on effect assessment using in vitro toxicity testing, indirect exposures through the food chain, and parallel means of data collection (e.g. through ecosurveillance or public consultation), are integrated in the Flemish approach. Even though the DSS is set up to provide a flexible and structured decision tree, the value of expert opinion is deemed essential to account for the many uncertainties associated with the early phases of technological incidents. When the DSS and the associated instruments will be fully operational, it will provide a valuable addition to the already available protocols, and will specifically safeguard public health interests.

  4. What are the key organisational capabilities that facilitate research use in public health policy?

    Science.gov (United States)

    Huckel Schneider, Carmen; Campbell, Danielle; Milat, Andrew; Haynes, Abby; Quinn, Emma

    2014-11-28

    Literature about research use suggests that certain characteristics or capabilities may make policy agencies more evidence attuned. This study sought to determine policy makers' perceptions of a suite of organisational capabilities identified from the literature as potentially facilitating research uptake in policy decision making. A literature scan identified eight key organisational capabilities that support research use in policy making. To determine whether these capabilities were relevant, practical and applicable in real world policy settings, nine Australian health policy makers were consulted in September 2011. We used an open-ended questionnaire asking what facilitates the use of research in policy and program decision making, followed by specific questions rating the proposed capabilities. Interviews were transcribed and the content analysed. There was general agreement that the capabilities identified from the literature were relevant to real world contexts. However, interviewees varied in whether they could provide examples of experiences with the capabilities, how essential they considered the different capabilities to be and how difficult they considered the capabilities were to achieve. Efforts to improve the use of research in policy decision making are likely to benefit from targeting multiple organisational capabilities, including staff skills and competence, tools such as templates and checklists to aid evidence use and leadership support for the use of research in policy development. However, such efforts should be guided by an understanding of how policy agencies use evidence and how they view their roles, and external factors such as resource constraints and availability of appropriate research.

  5. Public health and social injustice are the key issues for the decriminalization of abortion in Mexico.

    Science.gov (United States)

    1994-01-01

    Although the Second National Abortion Survey Gallup found that 88% of Mexicans believe abortion should be a woman's choice and 77% think the decriminalization of abortion would substantially reduce maternal mortality, abortion in Mexico remains governed by a 1931 criminal code. The survey was initiated by the Information and Reproductive Choice Group to provide information for the 1994 national debate on abortion. Supporters of legal abortion note that poor women resort to unsafe pregnancy terminations without regard to the criminal status of abortion. According to Patricia Mercado, co-founder of the Reproductive Choice Group, "You can be against abortion, but still allow it to be decriminalized. In other words, criminalization does not prevent women from having abortions, it only makes then have then in bad conditions. The idea is that women should be able to decide freely without risking problems of health and social justice." Despite public support for abortion legalization, survey results indicate widespread fear about acknowledging the existence of clandestine abortion. An estimated 1-2 million illegal abortions occur each year in Mexico, yet only 26% of survey respondents would admit to knowing a woman who had undergone illegal abortion.

  6. Generation of Biometric key for use in DES

    Directory of Open Access Journals (Sweden)

    Rupam Kumar Sharma

    2012-11-01

    Full Text Available Cryptography is an important field in the area of data encryption. There are different cryptographic techniques available varying from the simplest to complex. One of the complex symmetric key cryptography techniques is using Data Encryption Standard Algorithm. This paper explores a unique approach to generation of key using fingerprint. The generated key is used as an input key to the DES Algorithm

  7. 基于Chebyshev的概率公钥密码体制%Probabilistic public-key cryptosystem based on Chebyshev

    Institute of Scientific and Technical Information of China (English)

    程学海; 徐江峰

    2013-01-01

    This paper introduced the definition and the properties of Chebyshev polynomial.According to the deterministic public-key cryptosystem of Chebyshev polynomial,found that it couldn't resist chosen cipher-text attacks.Combining with the security model against chosen cipher-text attacks,this paper proposed the probabilistic public-key cryptosystem of Chebyshev polynomial.The analysis show that the proposed cryptosystem is correct.Through the result of the reduction proof,the proposed cryptosystem can resist the adaptive chosen cipher-text attacks and has the IND-CCA2 security.%介绍了Chebyshev多项式的定义和相关性质,针对确定性Chebyshev多项式公钥密码体制进行了研究,发现其不能抵抗选择密文攻击.结合抵抗选择密文攻击的安全模型,提出了基于有限域的Chebyshev多项式的概率公钥密码体制,分析结果表明该密码体制是正确的.通过归约证明,该密码体制能够抵挡适应性选择密文攻击,具有抵抗选择密文攻击的IND-CCA2安全性.

  8. Resilience Analysis of Key Update Strategies for Resource-Constrained Networks

    DEFF Research Database (Denmark)

    Yuksel, Ender; Nielson, Hanne Riis; Nielson, Flemming

    2011-01-01

    Severe resource limitations in certain types of networks lead to various open issues in security. Since such networks usually operate in unattended or hostile environments, revoking the cryptographic keys and establishing (also distributing) new keys – which we refer to as key update – is a criti...

  9. Resilience Analysis of Key Update Strategies for Resource-Constrained Networks

    DEFF Research Database (Denmark)

    Yuksel, Ender; Nielson, Hanne Riis; Nielson, Flemming

    2011-01-01

    Severe resource limitations in certain types of networks lead to various open issues in security. Since such networks usually operate in unattended or hostile environments, revoking the cryptographic keys and establishing (also distributing) new keys – which we refer to as key update – is a criti...

  10. Secret-key agreement over spatially correlated fast-fading multiple-antenna channels with public discussion

    KAUST Repository

    Zorgui, Marwen

    2015-06-14

    We consider secret-key agreement with public discussion over multiple-input multiple-output (MIMO) Rayleigh fast-fading channels under correlated environment. We assume that transmit, legitimate receiver and eavesdropper antennas are correlated. The legitimate receiver and the eavesdropper are assumed to have perfect channel knowledge while the transmitter has only knowledge of the correlation matrices. First, we derive the expression of the secret-key capacity under the considered setup. Then, we prove that the optimal transmit strategy achieving the secret-key capacity consists in transmitting independent Gaussian signals along the eingenvectors of the transmit correlation matrix. The powers allocated to each channel mode are determined as the solution to a numerical optimization problem that we derive. A necessary and sufficient condition for beamforming (i.e., transmitting along the strongest channel mode) to be capacity-achieving is derived. Finally, we analyze the impact of correlation matrices on the system performance and provide closed-form expressions of the gain/loss due to correlation in the high power regime.

  11. A Multi-Threaded Cryptographic Pseudorandom Number Generator Test Suite

    Science.gov (United States)

    2016-09-01

    be a practical attack on the key. More recently, improper initialization of the PRNG led to android digital wallets being hijacked [4]. For military...a practical attack on the key. More 3 recently, improper initialization of a PRNG led to android digital wallets being hijacked [4]. Adopting the...appears to exist differentiating it from random, however, is both intuitive and natural. As a result, statistical test suites have been developed which

  12. Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal - a case study from health science.

    Science.gov (United States)

    Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne

    2016-01-01

    Unique identifiers (UID) are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication.  The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of UIDs may become

  13. Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal – a case study from health science

    Science.gov (United States)

    Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne

    2016-01-01

    Unique identifiers (UID) are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication.  The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI), incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of UIDs may become

  14. Multimode-multivariate public key cryptosystem%多模式多变量公钥密码体制

    Institute of Scientific and Technical Information of China (English)

    孙小雁; 张茂胜

    2012-01-01

    A multimode-multivariate public key cryptosystem is developed for resisting the quantum algorithm. Since quantum computers are not efficient to solve multivariate polynomial problems, the multivariate public key cryptosystem is secure. In order to improve the computational efficiency, the branching modification is used. During the process of every branch, the plus modifier, minus modifier and iteration are combined. Analysis results show that the proposed scheme can resist known types of attacks. And thus it can be applied to encryption/decryption, signature and integrity.%针对量子计算机对公钥密码体制的挑战,提出一种能抵抗量子算法的多模式多变量公钥密码算法.量子计算机在解决多变量多项式问题并无高效算法,在传统多变量公钥密码体制的基础上,使用多分支模式,在分支内部采用加模式、减模式和迭代模式,增强了多变量公钥密码体制的安全性.通过分析各种常见攻击的复杂度,多模式多变量公钥密码体制能有效抵抗各种攻击,可以应用于加解密、签名和数据完整性验证.

  15. PUBLIC KEY INFRASTRUCTURE (PKI)

    Data.gov (United States)

    Federal Laboratory Consortium — Common Access Card (CAC)Enterprise Testing Overview:Established in 2003Performs test and evaluations of the DOD PKI CAC issuance systems from an enterprise level all...

  16. PUBLIC KEY INFRASTRUCTURE (PKI)

    Data.gov (United States)

    Federal Laboratory Consortium — Common Access Card (CAC) Enterprise Testing Overview: Established in 2003 Performs test and evaluations of the DOD PKI CAC issuance systems from an enterprise level...

  17. On the construction of cryptographically strong Boolean functions with desirable trade-off

    Institute of Scientific and Technical Information of China (English)

    REN Kui; PARK Jaemin; KIM Kwangjo

    2005-01-01

    This paper proposes a practical algorithm for systematically generating strong Boolean functions (f:GF(2)n→GF(2))with cryptographic meaning. This algorithm takes bent function as input and directly outputs the resulted Boolean function in terms of truth table sequence. This algorithm was used to develop two classes of balanced Boolean functions, one of which has very good cryptographic properties: nl(f)=22k-1-2k+2k-2 (n=2k), with the sum-of-squares avalanche characteristic off satisfying σf=24k+23k+2+23k+23k-2 and the absolute avalanche characteristic of △f satisfying △f=2k+1. This is the best result up to now compared to existing ones. Instead of bent sequences, starting from random Boolean functions was also tested in the algorithm. Experimental results showed that starting from bent sequences is highly superior to starting from random Boolean functions.

  18. Public assessment of key performance indicators of healthcare in a Canadian province: the effect of age and chronic health problems.

    Science.gov (United States)

    Nurullah, Abu Sadat; Northcott, Herbert C; Harvey, Michael D

    2014-01-15

    This study explores the effect of age and chronic conditions on public perceptions of the health system, as measured by the Key Performance Indicators (KPIs) of healthcare, in the province of Alberta in Canada. Drawing from data collected by Government of Alberta's Department of Health and Wellness, this research examines two key questions: (1) Do people in the 65+ age group rate the KPIs of healthcare (i.e., availability, accessibility, quality, outcome, and satisfaction) more favorably compared to people in younger age groups in Alberta? (2) Does the rating of KPIs of healthcare in Alberta vary with different chronic conditions (i.e., no chronic problem, chronic illnesses without pain, and chronic pain)? The findings indicate that people in the older age group tend to rate the KPIs of healthcare more favorably compared to younger age groups in Alberta, net of socio-demographic factors, self-reported health status, and knowledge and utilization of health services. However, people experiencing chronic pain are less likely to rate the KPIs of healthcare favorably compared to people with no chronic health problem in Alberta. Discussion includes implications of the findings for the healthcare system in the province.

  19. A Real-Time Performance Analysis Model for Cryptographic Protocols

    Directory of Open Access Journals (Sweden)

    Amos Olagunju

    2012-12-01

    Full Text Available Several encryption algorithms exist today for securing data in storage and transmission over network systems. The choice of encryption algorithms must weigh performance requirements against the call for protection of sensitive data. This research investigated the processing times of alternative encryption algorithms under specific conditions. The paper presents the architecture of a model multiplatform tool for the evaluation of candidate encryption algorithms based on different data and key sizes. The model software was used to appraise the real-time performance of DES, AES, 3DES, MD5, SHA1, and SHA2 encryption algorithms.

  20. Key exchange using biometric identity based encryption for sharing encrypted data in cloud environment

    Science.gov (United States)

    Hassan, Waleed K.; Al-Assam, Hisham

    2017-05-01

    The main problem associated with using symmetric/ asymmetric keys is how to securely store and exchange the keys between the parties over open networks particularly in the open environment such as cloud computing. Public Key Infrastructure (PKI) have been providing a practical solution for session key exchange for loads of web services. The key limitation of PKI solution is not only the need for a trusted third partly (e.g. certificate authority) but also the absent link between data owner and the encryption keys. The latter is arguably more important where accessing data needs to be linked with identify of the owner. Currently available key exchange protocols depend on using trusted couriers or secure channels, which can be subject to man-in-the-middle attack and various other attacks. This paper proposes a new protocol for Key Exchange using Biometric Identity Based Encryption (KE-BIBE) that enables parties to securely exchange cryptographic keys even an adversary is monitoring the communication channel between the parties. The proposed protocol combines biometrics with IBE in order to provide a secure way to access symmetric keys based on the identity of the users in unsecure environment. In the KE-BIOBE protocol, the message is first encrypted by the data owner using a traditional symmetric key before migrating it to a cloud storage. The symmetric key is then encrypted using public biometrics of the users selected by data owner to decrypt the message based on Fuzzy Identity-Based Encryption. Only the selected users will be able to decrypt the message by providing a fresh sample of their biometric data. The paper argues that the proposed solution eliminates the needs for a key distribution centre in traditional cryptography. It will also give data owner the power of finegrained sharing of encrypted data by control who can access their data.

  1. Techniques for Performance Improvement of Integer Multiplication in Cryptographic Applications

    Directory of Open Access Journals (Sweden)

    Robert Brumnik

    2014-01-01

    Full Text Available The problem of arithmetic operations performance in number fields is actively researched by many scientists, as evidenced by significant publications in this field. In this work, we offer some techniques to increase performance of software implementation of finite field multiplication algorithm, for both 32-bit and 64-bit platforms. The developed technique, called “delayed carry mechanism,” allows to preventing necessity to consider a significant bit carry at each iteration of the sum accumulation loop. This mechanism enables reducing the total number of additions and applies the modern parallelization technologies effectively.

  2. A novel key management scheme using biometrics

    Science.gov (United States)

    Sui, Yan; Yang, Kai; Du, Yingzi; Orr, Scott; Zou, Xukai

    2010-04-01

    Key management is one of the most important issues in cryptographic systems. Several important challenges in such a context are represented by secure and efficient key generation, key distribution, as well as key revocation. Addressing such challenges requires a comprehensive solution which is robust, secure and efficient. Compared to traditional key management schemes, key management using biometrics requires the presence of the user, which can reduce fraud and protect the key better. In this paper, we propose a novel key management scheme using iris based biometrics. Our newly proposed scheme outperforms traditional key management schemes as well as some existing key-binding biometric schemes in terms of security, diversity and/or efficiency.

  3. Security issues of quantum cryptographic systems with imperfect detectors

    Science.gov (United States)

    Burenkov, Viacheslav

    The laws of quantum physics can be used to secure communications between two distant parties in a scheme called quantum key distribution (QKD), even against a technologically unlimited eavesdropper. While the theoretical security of QKD has been proved rigorously, current implementations of QKD are generally insecure. In particular, mathematical models of devices, such as detectors, do not accurately describe their real-life behaviour. Such seemingly insignificant discrepancies can compromise the security of the entire scheme, especially as novel detector technologies are being developed with little regard for potential vulnerabilities. In this thesis, we study how detector imperfections can impact the security of QKD and how to overcome such technological limitations. We first analyze the security of a high-speed QKD system with finite detector dead time tau. We show that the previously reported sifting approaches are not guaranteed to be secure in this regime. More specifically, Eve can induce a basis-dependent detection efficiency at the receiver's end. Modified key sifting schemes that are basis-independent, and thus secure in the presence of dead time and an active eavesdropper, are discussed and compared. It is shown that the maximum key generation rate is 1/(2tau) for passive basis selection, and 1/tau for active basis selection. The security analysis is also extended to the decoy state BB84 protocol. We then study a relatively new type of single-photon detector called the superconducting nanowire single-photon detector (SNSPD), and discover some unexpected behaviour. We report an afterpulsing effect present when the SNSPD is operated in the high bias current regime. In our standard set-up, the afterpulsing is most likely to occur at around 180 ns following a detection event, for both real counts and dark counts. We characterize the afterpulsing behaviour and speculate that it is not due to the SNSPD itself but rather the associated read-out circuit. We also

  4. Multipartite Gaussian steering: monogamy constraints and cryptographical applications

    CERN Document Server

    Xiang, Yu; Adesso, Gerardo; He, Qiongyi

    2016-01-01

    We derive laws for the distribution of quantum steering among different parties in multipartite Gaussian states under Gaussian measurements. We prove that a monogamy relation akin to the generalized Coffman-Kundu-Wootters inequality holds quantitatively for a recently introduced measure of Gaussian steering. We then define the residual Gaussian steering, stemming from the monogamy inequality, as an indicator of collective steering-type correlations. For pure three-mode Gaussian states, the residual acts a quantifier of genuine multipartite steering, and is interpreted operationally in terms of the guaranteed key rate in the task of secure quantum secret sharing. Optimal resource states for the latter protocol are identified, and their possible experimental implementation discussed. Our results pin down the role of multipartite steering for quantum communication.

  5. Optimal Cryptographic Technique to increase the Data Security

    Directory of Open Access Journals (Sweden)

    K Laxmi Narayan

    2013-03-01

    Full Text Available There are many aspects to security ranging from secure commerce and payments to private communications and protecting passwords. One essential aspect for secure communications is that of secret key Cryptography. It is the automated method in which security goals are accomplished. It includes the process of encryption that converts plain-text into cipher-text. The process of decryption reconverts the cipher-text into plain-text. Secure communication is the prime requirement of every organization. To achieve this, one can use many techniques or algorithms available for Cryptography. In this context, we analyze and implement extremely protected cryptography scheme using the properties of quaternion which is the extension of the complex numbers and Farey fractions, Farey sequence of order n is the sequence of completely reduced fractions between 0 and 1. The proposed techniques in this paper can help in increasing the accurateness and wholeness of network topology discovery and can control existing protocol and hardware features, and also can be implemented easily.

  6. A Class of Key Predistribution Schemes Based on Orthogonal Arrays

    Institute of Scientific and Technical Information of China (English)

    Jun-Wu Dong; Ding-Yi Pei; Xue-Li Wang

    2008-01-01

    Pairwise key establishment is a fundamental security service in sensor networks; it enables sensor nodes to communicate securely with each other using cryptographic techniques. In order to ensure this security, many approaches have been proposed recently. One of them is to use key predistribution schemes for distributed sensor networks. The secure connectivity and resilience of the resulting sensor network are analyzed. This KPS constructed in our paper has some better properties than those of the existing schemes.

  7. Understanding security failures of two authentication and key agreement schemes for telecare medicine information systems.

    Science.gov (United States)

    Mishra, Dheerendra

    2015-03-01

    Smart card based authentication and key agreement schemes for telecare medicine information systems (TMIS) enable doctors, nurses, patients and health visitors to use smart cards for secure login to medical information systems. In recent years, several authentication and key agreement schemes have been proposed to present secure and efficient solution for TMIS. Most of the existing authentication schemes for TMIS have either higher computation overhead or are vulnerable to attacks. To reduce the computational overhead and enhance the security, Lee recently proposed an authentication and key agreement scheme using chaotic maps for TMIS. Xu et al. also proposed a password based authentication and key agreement scheme for TMIS using elliptic curve cryptography. Both the schemes provide better efficiency from the conventional public key cryptography based schemes. These schemes are important as they present an efficient solution for TMIS. We analyze the security of both Lee's scheme and Xu et al.'s schemes. Unfortunately, we identify that both the schemes are vulnerable to denial of service attack. To understand the security failures of these cryptographic schemes which are the key of patching existing schemes and designing future schemes, we demonstrate the security loopholes of Lee's scheme and Xu et al.'s scheme in this paper.

  8. The Homomorphism Analysis of Public Key Cryptosystem%公钥密码体制的同态性分析

    Institute of Scientific and Technical Information of China (English)

    闫世斗; 刘念; 李子臣

    2012-01-01

    Homomorphic encryption algorithm is based on the concept of homomorphism, which is a subset ot the homomorphism. Homomorphic encryption technology can do the operation to ciphertext directly, the op- eration results can be encrypted automatically, and the technology has a very broad application in secure multi - party computation, data encryption, electronic voting and other fields. A Homomorphic property in- cludes additively homomorphism, muhiplicatively homomorphism, and mixed multiplicatively homomor- phism. We study the homomorphic property of the three public key cryptosystem widely used now, and ana- lyze Pallier cryptosystem that meets additively homomorphism, which can provide theoretical basis and guid- ance to the follow - up study of fully homomorphic encryption algorithm.%同态加密算法是基于秘密同态的概念,是秘密同态的一个子集。同态加密技术可以对加密数据直接进行运算,并且运算结果也自动加密。正是基于此,使得同态加密技术在安全多方计算、数据库加密、电子投票等领域具有广泛的应用。同态特性主要包括加法特性、乘法特性、混合乘法特性。文章对目前广泛应用的三大公钥密码体制的同态特性进行了分析,并对满足加法同态的Pallier密码体制进行了研究。为后续研究全同态加密算法提供理论基础和方法指导。

  9. Efficient cryptographic substitution box design using travelling salesman problem and chaos

    Directory of Open Access Journals (Sweden)

    Musheer Ahmad

    2016-09-01

    Full Text Available Symmetric encryption has been a standout amongst the most reliable option by which security is accomplished. In modern block symmetric cyphers, the substitution-boxes have been playing a critical role of nonlinear components that drives the actual security of cyphers. In this paper, the travelling salesman problem and piece-wise linear chaotic map are explored to synthesize an efficient configuration of 8 × 8 substitution-box. The proposed anticipated design has the consistency which is justified by the standard performance indexes. The statistical results manifest that the prospective substitution-box is cryptographically more impressive as compared to some recent investigations.

  10. Anonymous One-Time Broadcast Using Non-interactive Dining Cryptographer Nets with Applications to Voting

    Science.gov (United States)

    van de Graaf, Jeroen

    All voting protocols proposed so far, with the exception of a few, have the property that the privacy of the ballot is only computational. In this paper we outline a new and conceptually simple approach allowing us to construct a protocol in which the privacy of the ballot is unconditional. Our basic idea is to modify the protocol of Fujioka, Okamoto and Ohta[1], which uses blind signatures so that the voter can obtain a valid ballot. However, instead of using a MIX net, we use a new broadcast protocol for anonymously publishing the vote, a Non-Interactive variation of the Dining Cryptographer Net.

  11. MEANING OF THE BITCOIN CRYPTOGRAPHIC CURRENCY AS A MEDIUM OF EXCHANGE

    Directory of Open Access Journals (Sweden)

    Łukasz Dopierała

    2014-06-01

    Full Text Available This article presents one of the new elements of virtual reality, which is the Bitcoin cryptocurrency. This thesis focuses on the condition and perspectives on development of the trading function of this instrument. The authors discuss the legal aspects of functioning of the Bitcoin, conduct a SWOT analysis of this cryptocurrency as a medium of exchange, and examin the scale of use of Bitcoin in transaction purposes. As of March 1, 2014 the trading system gradually develops and the strengths of this cryptographic currency outweigh its weaknesses, but the future of Bitcoin as a medium of exchange is difficult to determine.

  12. The FPGA realization of the general cellular automata based cryptographic hash functions: Performance and effectiveness

    Directory of Open Access Journals (Sweden)

    P. G. Klyucharev

    2014-01-01

    Full Text Available In the paper the author considers hardware implementation of the GRACE-H family general cellular automata based cryptographic hash functions. VHDL is used as a language and Altera FPGA as a platform for hardware implementation. Performance and effectiveness of the FPGA implementations of GRACE-H hash functions were compared with Keccak (SHA-3, SHA-256, BLAKE, Groestl, JH, Skein hash functions. According to the performed tests, performance of the hardware implementation of GRACE-H family hash functions significantly (up to 12 times exceeded performance of the hardware implementation of previously known hash functions, and effectiveness of that hardware implementation was also better (up to 4 times.

  13. SECOQC White Paper on Quantum Key Distribution and Cryptography

    CERN Document Server

    Alleaume, R; Branciard, C; Debuisschert, T; Dianati, M; Gisin, N; Godfrey, M; Grangier, P; Langer, T; Leverrier, A; Lütkenhaus, N; Painchault, P; Peev, M; Poppe, A; Pornin, T; Rarity, J; Renner, R; Ribordy, G; Riguidel, M; Salvail, L; Shields, A; Weinfurter, H; Zeilinger, A; Alleaume, Romain; Bouda, Jan; Branciard, Cyril; Debuisschert, Thierry; Dianati, Mehrdad; Gisin, Nicolas; Godfrey, Mark; Grangier, Philippe; Langer, Thomas; Leverrier, Anthony; Lutkenhaus, Norbert; Painchault, Philippe; Peev, Momtchil; Poppe, Andreas; Pornin, Thomas; Rarity, John; Renner, Renato; Ribordy, Gregoire; Riguidel, Michel; Salvail, Louis; Shields, Andrew; Weinfurter, Harald; Zeilinger, Anton

    2007-01-01

    The SECOQC White Paper on Quantum Key Distribution and Cryptography is the outcome on a thorough consultation and discussion among the participants of the European project SECOQC (www.secoqc.net). This paper is a review article that attempts to position Quantum Key Distribution (QKD) in terms of cryptographic applications. A detailed comparison of QKD with the solutions currently in use to solve the key distribution problem, based on classical cryptography, is provided. We also detail how the work on QKD networks lead within SECOQC will allow the deployment of long-distance secure communication infrastructures based on quantum cryptography. The purpose of the White Paper is finally to promote closer collaboration between classical and quantum cryptographers. We believe that very fruitful research, involving both communities, could emerge in the future years and try to sketch what may be the next challenges in this direction.

  14. Perspectives on key principles of generalist medical practice in public service in sub-saharan africa: a qualitative study

    Directory of Open Access Journals (Sweden)

    Downing Raymond V

    2011-07-01

    Full Text Available Abstract Background The principles and practice of Family Medicine that arose in developed Western countries have been imported and adopted in African countries without adequate consideration of their relevance and appropriateness to the African context. In this study we attempted to elicit a priori principles of generalist medical practice from the experience of long-serving medical officers in a variety of African counties, through which we explored emergent principles of Family Medicine in our own context. Methods A descriptive study design was utilized, using qualitative methods. 16 respondents who were clinically active medical practitioners, working as generalists in the public services or non-profit sector for at least 5 years, and who had had no previous formal training or involvement in academic Family Medicine, were purposively selected in 8 different countries in southern, western and east Africa, and interviewed. Results The respondents highlighted a number of key issues with respect to the external environment within which they work, their collective roles, activities and behaviours, as well as the personal values and beliefs that motivate their behaviour. The context is characterized by resource constraints, high workload, traditional health beliefs, and the difficulty of referring patients to the next level of care. Generalist clinicians in sub-Saharan Africa need to be competent across a wide range of clinical disciplines and procedural skills at the level of the district hospital and clinic, in both chronic and emergency care. They need to understand the patient's perspective and context, empowering the patient and building an effective doctor-patient relationship. They are also managers, focused on coordinating and improving the quality of clinical care through teamwork, training and mentoring other health workers in the generalist setting, while being life-long learners themselves. However, their role in the community, was

  15. Introduction of Renal Key Performance Indicators Associated with Increased Uptake of Peritoneal Dialysis in a Publicly Funded Health Service.

    Science.gov (United States)

    Toussaint, Nigel D; McMahon, Lawrence P; Dowling, Gregory; Holt, Stephen G; Smith, Gillian; Safe, Maria; Knight, Richard; Fair, Kathleen; Linehan, Leanne; Walker, Rowan G; Power, David A

    2017-01-01

    ♦ BACKGROUND: Increased demand for treatment of end-stage kidney disease has largely been accommodated by a costly increase in satellite hemodialysis (SHD) in most jurisdictions. In the Australian State of Victoria, a marked regional variation in the uptake of home-based dialysis suggests that use of home therapies could be increased as an alternative to SHD. An earlier strategy based solely on increased remuneration had failed to increase uptake of home therapies. Therefore, the public dialysis funder adopted the incidence and prevalence of home-based dialysis therapies as a key performance indicator (KPI) for its health services to encourage greater uptake of home therapies. ♦ METHODS: A KPI data collection and bench-marking program was established in 2012 by the Victorian Department of Health and Human Services, with data provided monthly by all renal units in Victoria using a purpose-designed website portal. A KPI Working Group was responsible for analyzing data each quarter and ensuring indicators remained accurate and relevant and each KPI had clear definitions and targets. We present a prospective, observational study of all dialysis patients in Victoria over a 4-year period following the introduction of the renal KPI program, with descriptive analyses to evaluate the proportion of patients using home therapies as well as home dialysis modality survival. ♦ RESULTS: Following the introduction of the KPI program, the net growth of dialysis patient numbers in Victoria remained stable over 4 years, at 75 - 80 per year (approximately 4%). However, unlike the previous decade, about 40% of this growth was through an increase in home dialysis, which was almost exclusively peritoneal dialysis (PD). The increase was identified particularly in the young (20 - 49) and the elderly (> 80). Disappointingly, however, 67% of these incident patients ceased PD within 2 years of commencement, 46% of whom transferred to SHD. ♦ CONCLUSIONS: Introduction of a KPI program

  16. A new class of codes for Boolean masking of cryptographic computations

    CERN Document Server

    Carlet, Claude; Kim, Jon-Lark; Solé, Patrick

    2011-01-01

    We introduce a new class of rate one half binary codes: complementary information set codes. A binary linear code of length 2n and dimension n is called a complementary information set code (CIS code for short) if it has two disjoint information sets. This class of codes contains self-dual codes as a subclass. It is connected to graph correlation immune Boolean functions of use in the security of hardware implementations of cryptographic primitives. Such codes permit to improve the cost of masking cryptographic algorithms against side channel attacks. In this paper we investigate this new class of codes: we give optimal or best known CIS codes of length < 132. We derive general constructions based on cyclic codes and on double circulant codes. We derive a Varshamov-Gilbert bound for long CIS codes, and show that they can all be classified in small lengths \\leq 12 by the building up construction. Some nonlinear S-boxes are constructed by using Z4-codes, based on the notion of dual distance of an unrestricte...

  17. The El-Gamal AA_{\\beta} Public Key Cryptosystem - A new approach utilizing the subset sum problem in designing an asymmetric cryptosystem

    CERN Document Server

    Ariffin, Muhammad Rezal Kamel; Ghani, Aniza Abdul; Atan, Kamel Ariffin Mohd; Abu, Nor Azman

    2010-01-01

    The El-Gamal AA_{\\beta} Public Key Cryptosystem is a new asymmetric cryptosystem based on the piecewise AA_{\\beta}-function. The AA_{\\beta}-function which is essentially a one way Boolean function was motivated by the squaring and multiplying process while computing g^a (mod p) in the Diffie Hellman key exchange procedure and also computing C \\equiv M^e (mod N) and M \\equiv C^d (mod N) in the RSA cryptosystem. It was also motivated by the add and double point operation E=kG in the elliptic curve cryptosystem. The hard mathematical problem surrounding this newly designed asymmetric cryptosystem is the NP-complete problem known as the subset sum problem. The El-Gamal AA_{\\beta} Public Key Cryptosystem mimics the El-Gamal Cryptosystem and the Elliptic Curve Cryptosystem by sending a two parameter ciphertext to the recipient.

  18. Quantum Encoder and Decoder for Secret Key Distribution with Check Bits

    Directory of Open Access Journals (Sweden)

    T. Godhavari

    2013-12-01

    Full Text Available The focus of this study is to develop a novel method of encoding the qubits and use as secret key in public key cryptography. In BB 84 protocol, 50% of the random number (generated at source is used as secret key and the remaining bits are used as “check bits”. The check bits are used to detect the presence of eve as well as the nature of quantum channels. In this protocol, random qubits are encoded using different type of polarizations like horizontal, veritical and diagonal. In the proposed quantum encoder, basic quantum gates are used to encode the random secret key along with the check bits. Quantum key distribution, (a cryptographic mechanism relies on the inherent randomness of quantum mechanics and serves as an option to replace techniques made vulnerable by quantum computing. However, it is still subject to clever forms of eavesdropping and poses a significant challenge to implementation. To study the challenges, quantum circuits are first simulated using QCAD.

  19. Cryptographic Protocols:

    DEFF Research Database (Denmark)

    Geisler, Martin Joakim Bittel

    The art of keeping messages secret is ancient. It must have been invented only shortly after the invention of the messages themselves. Merchants and generals have always had a need to exchange critical messages while keeping them secret from the prying eyes of competitors or the enemy. Classical...... framework. We call this framework VIFF, short for Virtual Ideal Functionality Framework. VIFF implements a UC functionality for general multiparty computation on asynchronous networks. We give a formal definition of the functionality in Chapter 3. There we also describe how we implemented the functionality...

  20. Cryptographic Protocols:

    DEFF Research Database (Denmark)

    Geisler, Martin Joakim Bittel

    framework. We call this framework VIFF, short for Virtual Ideal Functionality Framework. VIFF implements a UC functionality for general multiparty computation on asynchronous networks. We give a formal definition of the functionality in Chapter 3. There we also describe how we implemented the functionality...

  1. Key-Alternating Ciphers in a Provable Setting: Encryption Using a Small Number of Public Permutations (Extended Abstract)

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Knudsen, L.R.; Leander, Gregor

    2012-01-01

    show that the distribution of Fourier coefficients for the cipher over all keys is close to ideal. Lastly, we define a practical instance of the construction with t = 2 using AES referred to as AES2. Any attack on AES2 with complexity below 285 will have to make use of AES with a fixed known key...

  2. Key-Alternating Ciphers in a Provable Setting: Encryption Using a Small Number of Public Permutations (Extended Abstract)

    DEFF Research Database (Denmark)

    Bogdanov, Andrey; Knudsen, L.R.; Leander, Gregor

    2012-01-01

    This paper considers—for the first time—the concept of key-alternating ciphers in a provable security setting. Key-alternating ciphers can be seen as a generalization of a construction proposed by Even and Mansour in 1991. This construction builds a block cipher PX from an n-bit permutation P and...

  3. 公安网络舆情分析中的关键技术研究%Research on key technologies of public security network public opinion analysis

    Institute of Scientific and Technical Information of China (English)

    李燕

    2015-01-01

    Faced with online public opinions, It’s a practical problem which must be deeply studied and confronted for the public security organs on how to find , collect, analyze and deal with these opinions timely, and effectively enhance the credibility of the public security organization. Therefore, this article will be focused on a study related to public security methods and techniques involved in the network public opinion analysis.%面对网络舆情,公安机关如何及时发现并采集、分析并处理,切实提升公安机关的公信力,是公安机关必须深入研究和对待的现实问题。本文重点就公安网络舆情分析中涉及的相关方法和技术展开研究。

  4. A NOVEL APPROACH FOR INFORMATION SECURITY IN AD HOC NETWORKS THROUGH SECURE KEY MANAGEMENT

    Directory of Open Access Journals (Sweden)

    S. Suma Christal Mary

    2013-01-01

    Full Text Available Ad hoc networks provide flexible and adaptive networks with no fixed infrastructure and dynamic topology. Owe to the vulnerability nature of ad hoc network, there are lots of security threats that diminish the development of ad hoc networks. Therefore, to provide security for information of users and to preserve their privacy, it becomes mandatory to use cryptographic techniques to set up secure mobile ad hoc network. Earlier cryptographic method based on computational complexity ruins with the advent of fast computing computers. In this proposal, we proposed Secure Key Management (SKM framework. We make use of McEliece algorithm embedded with Dispense Key designed for key generation and for the key distribution and it is highly scalable with respect to memory. The experimental result shows that our framework provides a high-performance platform to execute key generation, key distribution scenarios. SKM framework reduces execution time of encryption and decryption by minimizing the number of keys.

  5. Error tolerance of two-basis quantum key-distribution protocols using qudits and two-way classical communication

    CERN Document Server

    Nikolopoulos, G M; Ranade, K S; Alber, Gernot; Nikolopoulos, Georgios M.; Ranade, Kedar S.

    2006-01-01

    We investigate the error tolerance of quantum cryptographic protocols using $d$-level systems. In particular, we focus on prepare-and-measure schemes that use two mutually unbiased bases and a key-distillation procedure with two-way classical communication. For arbitrary quantum channels, we obtain a sufficient condition for secret-key distillation which, in the case of isotropic quantum channels, yields an analytic expression for the maximally tolerable error rate of the cryptographic protocols under consideration. The difference between the tolerable error rate and its theoretical upper bound tends slowly to zero for sufficiently large dimensions of the information carriers.

  6. Challenges, alternatives, and paths to sustainability: better public health promotion using social networking pages as key tools.

    Science.gov (United States)

    Zaidan, A A; Zaidan, B B; Kadhem, Z; Larbani, M; Lakulu, M B; Hashim, M

    2015-02-01

    This paper discusses the possibility of promoting public health and implementing educational health services using Facebook. We discuss the challenges and strengths of using such a platform as a tool for public health care systems from two different perspectives, namely, the view of IT developers and that of physicians. We present a new way of evaluating user interactivity in health care systems from tools provided by Facebook that measure statistical traffic in the Internet. Findings show that Facebook is a very promising tool in promoting e-health services in Web 2.0. Results from statistical traffic show that a Facebook page is more efficient than other pages in promoting public health.

  7. Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal

    DEFF Research Database (Denmark)

    Madsen, Heidi Holst; Madsen, Dicte; Gauffriau, Marianne

    2016-01-01

    , and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character...... recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation...

  8. 可撤销的公钥加密方案的形式化分析%Revocable Public-Key Cryptosystems Formal Analysis

    Institute of Scientific and Technical Information of China (English)

    于瑞琴

    2011-01-01

    通常的密码系统,IBE或者PKI都必须提供从系统中撤销用户私钥的途径,同样PEKS也应该提供撤销陷门的方式.本文研究了可高效撤销的无需安全信道的带关键字搜索公钥加密方案的形式化定义及安全模型.基于BDH问题,可证明方案的安全性.%Any setting,Public-key Infrastructure or Identity-Based.Must provide a means to revoke users from the system.Efficient revocation is a well-studied problem in the traditional Public-Key Infrastructure or Identity-Based Encryption.We propose revocable public key encryption with Key words search scheme of formalized definition and the security model in the paper.Based on bilinear dilinear diffie-hellman,the security of the scheme can be proved.

  9. Designing and implementing of improved cryptographic algorithm using modular arithmetic theory

    Directory of Open Access Journals (Sweden)

    Maryam Kamarzarrin

    2015-05-01

    Full Text Available Maintaining the privacy and security of people information are two most important principles of electronic health plan. One of the methods of creating privacy and securing of information is using Public key cryptography system. In this paper, we compare two algorithms, Common And Fast Exponentiation algorithms, for enhancing the efficiency of public key cryptography. We express that a designed system by Fast Exponentiation Algorithm has high speed and performance but low power consumption and space occupied compared with Common Exponentiation algorithm. Although designed systems by Common Exponentiation algorithm have slower speed and lower performance, designing by this algorithm has less complexity, and easier designing compared with Fast Exponentiation algorithm. In this paper, we will try to examine and compare two different methods of exponentiation, also observe performance Impact of these two approaches in the form of hardware with VHDL language on FPGA.

  10. 基于身份的一次性盲公钥方案%One-off Blind Public Key Scheme Based on Identity

    Institute of Scientific and Technical Information of China (English)

    赵伟艇; 申远

    2012-01-01

    在现有方案的基础上,通过分析超椭圆曲线双线性对和基于身份的特点,给出了一个改进的基于身份的一次性盲公钥方案.该方案由用户和可信中心共同完成用户密钥的生成,克服了密钥托管问题,避免了由可信中心进行密钥管理所产生的安全隐患.新构造的方案能够抵抗伪造性攻击,具有不可欺骗性,又保证了一次性盲公钥的独立性,是安全可靠的.而且方案中用户在通讯时可以使用不同的公钥,解决了Internet通信中的匿名认证问题,实现了用户隐私的有效保护.%By analyzing the characteristic of the bilinear pairings on hyper-elliptic curves and identity-based cryptography, an improved one-off blind public key scheme based on the existing schemes is proposed. The scheme solves the problem of the key escrow by users and trust center generated encryption key, so it avoids security problems caused by single independent key management. The scheme is robust a-gainst the Forgery attack and ensures the independence of user's public key. This scheme is satisfied. And user's public key is different ever-y time, it can be applied to implementing internet anonymous attestation for privacy protection.

  11. FINGERPRINT-BASED KEY BINDING/RECOVERING SCHEME BASED ON FUZZY VAULT

    Institute of Scientific and Technical Information of China (English)

    Feng Quan; Su Fei; Cai Anni

    2008-01-01

    This letter proposes fingerprint-based key binding/recovering with fuzzy vault. Fingerprint minutiae data and the cryptographic key are merged together by a multivariable linear function. First,the minutiae data are bound by a set of random data through the linear function. The number of the function's variables is determined by the required number of matched minutiae. Then, a new key derived from the random data is used to encrypt the cryptographic key. Lastly, the binding data are protected using fuzzy vault scheme. The proposed scheme provides the system with the flexibility to use changeable number of minutiae to bind/recover the protected key and a unified method regardless of the length of the key.

  12. MiMC: Efficient encryption and cryptographic hashing with minimal multiplicative complexity

    DEFF Research Database (Denmark)

    Albrecht, Martin; Grassi, Lorenzo; Rechberger, Christian;

    2016-01-01

    We explore cryptographic primitives with low multiplicative complexity. This is motivated by recent progress in practical applications of secure multi-party computation (MPC), fully homomorphic encryption (FHE), and zero-knowledge proofs (ZK) where primitives from symmetric cryptography are needed...... and where linear computations are, compared to non-linear operations, essentially “free”. Starting with the cipher design strategy “LowMC” from Eurocrypt 2015, a number of bitoriented proposals have been put forward, focusing on applications where the multiplicative depth of the circuit describing...... a new attack vector that outperforms others in relevant settings. Due to its very low number of multiplications, the design lends itself well to a large class of applications, especially when the depth does not matter but the total number of multiplications in the circuit dominates all aspects...

  13. The SAT solving method as applied to cryptographic analysis of asymmetric ciphers

    CERN Document Server

    Faizullin, R T; Dylkeyt, V I

    2009-01-01

    The one of the most interesting problem of discrete mathematics is the SAT (satisfiability) problem. Good way in SAT solver developing is to transform the SAT problem to the problem of continuous search of global minimums of the functional associated with the CNF. This article proves the special construction of the functional and offers to solve the system of non-linear algebraic equation that determines functional stationary points via modified method of consecutive approximation. The article describes parallel versions of the method. Also gives the schema of using the method to important problems of cryptographic analysis of asymmetric ciphers, including determining concrete bits of multipliers (in binary form) in large factorization problems and concrete bits of exponent of discrete logarithm problem.

  14. Efficient Implementation of Electronic Passport Scheme Using Cryptographic Security Along With Multiple Biometrics

    Directory of Open Access Journals (Sweden)

    V.K. NARENDIRA KUMAR

    2012-02-01

    Full Text Available Electronic passports have known a wide and fast deployment all around the world since the International Civil Aviation Organization the world has adopted standards whereby passports can store biometric identifiers. The use of biometrics for identification has the potential to make the lives easier, and the world people live in a safer place. The purpose of biometric passports is to prevent the illegal entry of traveler into a specific country and limit the use of counterfeit documents by more accurate identification of an individual. The paper analyses the face, fingerprint, palm print and iris biometric e-passport design. The paper also provides a cryptographic security analysis of the e-passport using face fingerprint, palm print and iris biometric that are intended to provide improved security in protecting biometric information of the e-passport bearer.

  15. Key Management in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Ismail Mansour

    2015-09-01

    Full Text Available Wireless sensor networks are a challenging field of research when it comes to security issues. Using low cost sensor nodes with limited resources makes it difficult for cryptographic algorithms to function without impacting energy consumption and latency. In this paper, we focus on key management issues in multi-hop wireless sensor networks. These networks are easy to attack due to the open nature of the wireless medium. Intruders could try to penetrate the network, capture nodes or take control over particular nodes. In this context, it is important to revoke and renew keys that might be learned by malicious nodes. We propose several secure protocols for key revocation and key renewal based on symmetric encryption and elliptic curve cryptography. All protocols are secure, but have different security levels. Each proposed protocol is formally proven and analyzed using Scyther, an automatic verification tool for cryptographic protocols. For efficiency comparison sake, we implemented all protocols on real testbeds using TelosB motes and discussed their performances.

  16. ELGamal public key cryptosystem based on multiplicative group Zp*%基于乘法群Zp*的ELGamal公钥密码系统

    Institute of Scientific and Technical Information of China (English)

    孙立宏

    2011-01-01

    为了解决发送方与接收方不能识别对方身份的问题,在研究E1Gamal密码体制的基础上,给出了一种基于乘法群Zn*的ELGamal公钥密码体制。结果表明:该算法可以实现通信双方的双向身份认证,有效地防止了攻击者冒充发送方伪造要发送的消息。同时该算法在通信过程中加入了可以追踪消息来源的信息,使得接收者可以对消息的真实性进行有效的验证。通过对消息的双重保护,该体制实现了在公开信道上的安全通信。%In the public key cryptography system, the sender encrypts the messages with the recipient's public key and the receiver decrypts them with their own secret key, which results in that the two sides are unable to recognize each other. In order to solve the problem above, an ELGamal public key cryptosystem based on multiplicative group Zp* has been presented in this paper. The bidirectional identity authentication between both communications sides are supplied in the proposed algorithm, which successfully prevents the attacker sending a forged message in the identity of sender. In addition, the algorithm also adds the information to track the sources of message in the communication process, which allows the message recipients verifying the authenticity of message effectively. The system implements a secured communication in the public channel through a dual protection on message.

  17. Embedded Platform for Automatic Testing and Optimizing of FPGA Based Cryptographic True Random Number Generators

    Directory of Open Access Journals (Sweden)

    M. Varchola

    2009-12-01

    Full Text Available This paper deals with an evaluation platform for cryptographic True Random Number Generators (TRNGs based on the hardware implementation of statistical tests for FPGAs. It was developed in order to provide an automatic tool that helps to speed up the TRNG design process and can provide new insights on the TRNG behavior as it will be shown on a particular example in the paper. It enables to test sufficient statistical properties of various TRNG designs under various working conditions on the fly. Moreover, the tests are suitable to be embedded into cryptographic hardware products in order to recognize TRNG output of weak quality and thus increase its robustness and reliability. Tests are fully compatible with the FIPS 140 standard and are implemented by the VHDL language as an IP-Core for vendor independent FPGAs. A recent Flash based Actel Fusion FPGA was chosen for preliminary experiments. The Actel version of the tests possesses an interface to the Actel’s CoreMP7 softcore processor that is fully compatible with the industry standard ARM7TDMI. Moreover, identical tests suite was implemented to the Xilinx Virtex 2 and 5 in order to compare the performance of the proposed solution with the performance of already published one based on the same FPGAs. It was achieved 25% and 65% greater clock frequency respectively while consuming almost equal resources of the Xilinx FPGAs. On the top of it, the proposed FIPS 140 architecture is capable of processing one random bit per one clock cycle which results in 311.5 Mbps throughput for Virtex 5 FPGA.

  18. First Chinese public hospital wins Joint Commission International accreditation: the Health Information Department played a key role in the process.

    Science.gov (United States)

    Shaffer, Audrey; Jun, Cheng Li

    2008-07-01

    Sir Run Run Shaw Hospital in Hangzhou, China spent five years preparing for a Joint Commission International accreditation survey. In March 2007 it became the first public hospital on the Chinese mainland to attain international accreditation. The Health Information Department, managed according to Western standards, played an integral role in preparing the hospital for the survey.

  19. Developing Key Performance Indicators to Measure the Effectiveness of Early Facilities Management Performance on BIM Governed Public Sector Projects

    OpenAIRE

    McAuley, Barry; Hore, Alan; West, Roger

    2015-01-01

    Governments across the globe are now recognising the need to take steps to better manage their property portfolios due to the escalating costs of operating these buildings over their lifetime. This has seen them turn towards innovative work practices and technologies offered by Building Information Modelling (BIM). It is now becoming increasingly evident that BIM can bring significant added value to the design, construction and most importantly to the operational life of a public sector devel...

  20. Dissemination of public health information: key tools utilised by the NECOBELAC network in Europe and Latin America

    Science.gov (United States)

    De Castro, Paola; Marsili, Daniela; Poltronieri, Elisabetta; Calderón, Carlos Agudelo

    2012-01-01

    Background Open Access (OA) to scientific information is an important step forward in communication patterns, yet we still need to reinforce OA principles to promote a cultural change of traditional publishing practices. The advantages of free access to scientific information are even more evident in public health where knowledge is directly associated with human wellbeing. Objectives An OA ‘consolidation’ initiative in public health is presented to show how the involvement of people and institutions is fundamental to create awareness on OA and promote a cultural change. This initiative is developed within the project NEtwork of COllaboration Between Europe and Latin American Caribbean countries (NECOBELAC), financed by the European Commission. Methods Three actions are envisaged: Capacity building through a flexible and sustainable training programme on scientific writing and OA publishing; creation of training tools based on semantic web technologies; development of a network of supporting institutions. Results In 2010–2011, 23 training initiatives were performed involving 856 participants from 15 countries; topic maps on scientific publication and OA were produced; 195 institutions are included in the network. Conclusions Cultural change in scientific dissemination practices is a long process requiring a flexible approach and strong commitment by all stakeholders. PMID:22630360

  1. 基于CPK组合公钥的电子签章技术研究%Study on Electronic Signature Technology based on Combined Public Key

    Institute of Scientific and Technical Information of China (English)

    范志强; 李成; 马兆丰; 芦效峰; 钮心忻

    2011-01-01

    With the development of e-government and e-commerce,the electronic documents have gradually replaced traditional paper-based documentation. Thus,how to ensure the security of the electronic document has become the key to the farther successful application of e-government and e-business.?The adoptions of CPK(Combined Public Key) in the design of electronic signature system and ID certificate in digital signature and verification,could make any two users confirm public key information only by their own identity labels with any dependence the trusted third party validation,thus simplifying the key exchange agreement,ensuring the documents integrity,confidentiality and undesirability,and realizing the efficient safe electronic signature system.%随着中国电子政务与电子商务的发展,电子文档已经逐渐取代传统的纸质文档。因此,如何保证电子文档的安全已经成为电子政务与电子商务进一步深入与成功应用的关键。采用组合公钥密码体制(Combined Public Key,CPK)设计电子签章系统,利用ID证书来进行数字签名与验证,使任何两个用户之间仅通过对方身份标识即可确认公钥信息,不依靠可信第三方验证,并简化了密钥交换协议,保证了文档的完整性、机密性和不可抵赖性,实现了高效安全的电子签章系统。

  2. Key points for developing an international declaration on nursing, human rights, human genetics and public health policy.

    Science.gov (United States)

    Anderson, G; Rorty, M V

    2001-05-01

    Human rights legislation pertaining to applications of human genetic science is still lacking at an international level. Three international human rights documents now serve as guidelines for countries wishing to develop such legislation. These were drafted and adopted by the United Nations Educational, Scientific and Cultural Organization, the Human Genome Organization, and the Council of Europe. It is critically important that the international nursing community makes known its philosophy and practice-based knowledge relating to ethics and human rights, and contributes to the globalization of genetics. Nurses have particular expertise because they serve in a unique role at grass roots level to mediate between genetic science and its application to public health policies and medical interventions. As a result, nurses worldwide need to focus a constant eye on human rights ideals and interpret these within social, cultural, economic and political contexts at national and local levels. The purpose of this article is to clarify and legitimate the need for an international declaration on nursing, human rights, human genetics and public health policy. Because nurses around the world are the professional workforce by which genetic health care services and genetic research protocols will be delivered in the twenty-first century, members of the discipline of nursing need to think globally while acting locally. Above all other disciplines involved in genetics, nursing is in a good position to articulate an expanded theory of ethics beyond the principled approach of biomedical ethics. Nursing is sensitive to cultural diversity and community values; it is sympathetic to and can introduce an ethic of caring and relational ethics that listen to and accommodate the needs of local people and their requirements for public health.

  3. Secure SCADA communication by using a modified key management scheme.

    Science.gov (United States)

    Rezai, Abdalhossein; Keshavarzi, Parviz; Moravej, Zahra

    2013-07-01

    This paper presents and evaluates a new cryptographic key management scheme which increases the efficiency and security of the Supervisory Control And Data Acquisition (SCADA) communication. In the proposed key management scheme, two key update phases are used: session key update and master key update. In the session key update phase, session keys are generated in the master station. In the master key update phase, the Elliptic Curve Diffie-Hellman (ECDH) protocol is used. The Poisson process is also used to model the Security Index (SI) and Quality of Service (QoS). Our analysis shows that the proposed key management not only supports the required speed in the MODBUS implementation but also has several advantages compared to other key management schemes for secure communication in SCADA networks.

  4. Two-round contributory group key exchange protocol for wireless network environments

    Directory of Open Access Journals (Sweden)

    Wu Tsu-Yang

    2011-01-01

    Full Text Available Abstract With the popularity of group-oriented applications, secure group communication has recently received much attention from cryptographic researchers. A group key exchange (GKE protocol allows that participants cooperatively establish a group key that is used to encrypt and decrypt transmitted messages. Hence, GKE protocols can be used to provide secure group communication over a public network channel. However, most of the previously proposed GKE protocols deployed in wired networks are not fully suitable for wireless network environments with low-power computing devices. Subsequently, several GKE protocols suitable for mobile or wireless networks have been proposed. In this article, we will propose a more efficient group key exchange protocol with dynamic joining and leaving. Under the decision Diffie-Hellman (DDH, the computation Diffie-Hellman (CDH, and the hash function assumptions, we demonstrate that the proposed protocol is secure against passive attack and provides forward/backward secrecy for dynamic member joining/leaving. As compared with the recently proposed GKE protocols, our protocol provides better performance in terms of computational cost, round number, and communication cost.

  5. An Efficient Key-Policy Attribute-Based Encryption Scheme with Constant Ciphertext Length

    Directory of Open Access Journals (Sweden)

    Changji Wang

    2013-01-01

    Full Text Available There is an acceleration of adoption of cloud computing among enterprises. However, moving the infrastructure and sensitive data from trusted domain of the data owner to public cloud will pose severe security and privacy risks. Attribute-based encryption (ABE is a new cryptographic primitive which provides a promising tool for addressing the problem of secure and fine-grained data sharing and decentralized access control. Key-policy attribute-based encryption (KP-ABE is an important type of ABE, which enables senders to encrypt messages under a set of attributes and private keys are associated with access structures that specify which ciphertexts the key holder will be allowed to decrypt. In most existing KP-ABE scheme, the ciphertext size grows linearly with the number of attributes embedded in ciphertext. In this paper, we propose a new KP-ABE construction with constant ciphertext size. In our construction, the access policy can be expressed as any monotone access structure. Meanwhile, the ciphertext size is independent of the number of ciphertext attributes, and the number of bilinear pairing evaluations is reduced to a constant. We prove that our scheme is semantically secure in the selective-set model based on the general Diffie-Hellman exponent assumption.

  6. Innovative electronic publication in plant systematics: PhytoKeys and the changes to the “Botanical Code” accepted at the XVIII International Botanical Congress in Melbourne

    Directory of Open Access Journals (Sweden)

    W. John Kress

    2011-09-01

    Full Text Available PhytoKeys was established less than a year ago in response to four main publication challenges of our time: (1 the appearance of electronic publications as amendments or even alternatives to paper publications; (2 Open Access (OA as a new publishing model; (3 the linkage of electronic registers, indices, and aggregators, which summarize information on biological species through taxonomic names or their persistent identifiers; and (4 Web 2.0 technologies, which permit the semantic markup of, and semantic enhancements to, published biological texts. The appearance of the journal was concomitant with lively discussions on the validity of nomenclatural acts published electronically (Knapp and Wright 2010, Knapp et al. 2010, Penev et al. 2010, Chapman et al. 2010. At the XVIII International Botanical Congress in Melbourne in July 2011 (IBC 2011 these discussions culminated in the decision to amend the International Code of Botanical Nomenclature to allow electronic-only publishing of new taxa. Even before the end of the Congress and formal acceptance of the changes PhytoKeys was able to publish a report on the main outcomes of the Nomenclature Section on electronic publishing (Miller et al. 2011.

  7. Modified Novel Quantum Key Exchange using BB84 Algorithm

    Directory of Open Access Journals (Sweden)

    N.Vivek Chetty

    2013-06-01

    Full Text Available With the increasing number of eavesdroppers on communication channels, securing the reliability of digital communication has become a herculean task. For any communication and information exchange the most important step of securing the data is encryption and decryption (cryptography. The primary step involved in any efficient cryptographic system is Key Distribution. The paper deals with an efficient Key Distribution Technique based on Quantum Mechanics. The concept of Heisenberg’s Uncertainty Principle and quantum indeterminacy property are used to detect the presence of eavesdropper and secure the process of Key Distribution.

  8. Efficient Identity Based Public Verifiable Signcryption Scheme

    OpenAIRE

    Kushwah, Prashant; Lal, Sunder

    2011-01-01

    Signcryption is a cryptographic primitive which performs encryption and signature in a single logical step. In conventional signcryption only receiver of the signcrypted text can verify the authenticity of the origin i.e. signature of the sender on the message after decrypting the cipher text. In public verifiable signcryption scheme anyone can verify the authenticity of the origin who can access the signcrypted text i.e. signature of the sender on the cipher text. Public verifiable signcrypt...

  9. Secure verifier-based three-party authentication schemes without server public keys for data exchange in telecare medicine information systems.

    Science.gov (United States)

    Lin, Tsung-Hung; Lee, Tian-Fu

    2014-05-01

    Secure verified-based three-party authentication scheme for data exchange in telecare medicine information systems enables two users only store their verifiers computed from their actual password in authentication server's database. Then the authentication server can verify the users' verifiers and help them to exchange electronic medical records or electronic health records securely and conveniently. This investigation presents an efficient and secure verified-based three-party authentication scheme for data exchange in telecare medicine information systems. The proposed scheme does not use server's public keys and includes the key confirmation without extra numbers of messages and rounds. Compared to related verified-based approaches, the proposed scheme possesses higher security, has lower computational cost and fewer transmissions, and thus is suitable for the telecare medicine information systems.

  10. A parallel realization for LUC algorithm of public key cryptosystems%公钥加密算法LUC的并行实现方法

    Institute of Scientific and Technical Information of China (English)

    杜珍珍; 陆正福; 周同; 杨春尧

    2016-01-01

    LUC是基于数论的公钥密码体制,相比RSA公钥密码体制,具有能够抵抗共模攻击的优点。但LUC算法因实现难度大,运算时间长而难以用于实际加密。而影响其运算速度的主要因素是密钥长度和模幂算法。本文参考相关文献工作,得到将密钥进行分段计算的公式,而后利用LUC序列的性质将密钥进行分段计算,并在多核系统下实现了LUC并行算法,从而提高了LUC算法的执行效率。%The LUC algorithm based on the number theory is one of the public key encryption, which resists common modu-lus attack comparing with the RSA public cyptosystem. But it is difficult for practical encryption and decryption as LUC is a long time of computing task. The main factor that affects the calculation speed of LUC encryption is key length and mode power algorithm. Reviewed with related references in this paper, we deduced the expression which computed by key division segmenta-tion, then applying the mathematical properties of LUC sequences, and the LUC algorithm is computed by key division segmen-tation, which is executed parallelly by implemented on multi-core platform, consequently, the computation efficiency of LUC al-gorithm is improved.

  11. Dynamic DNS update security, based on cryptographically generated addresses and ID-based cryptography, in an IPv6 autoconfiguration context

    OpenAIRE

    Combes, Jean-Michel; Arfaoui, Ghada; LAURENT, Maryline

    2012-01-01

    International audience; This paper proposes a new security method for protecting signalling for Domain Name System (DNS) architecture. That is, it makes secure DNS update messages for binding a Fully Qualified Domain Name (FQDN) of an IPv6 node and the IPv6 address of the node owning this FQDN. This method is based on the use of Cryptographically Generated Addresses (CGA) and IDBased Cryptography (IBC). Combination of these two techniques allows DNS server to check the ownership of the IPv6 a...

  12. 城乡公交一体化规划的关键技术%Key Technology of Integrated Planning of Urban and Rural Public Transportation

    Institute of Scientific and Technical Information of China (English)

    王献香

    2014-01-01

    Integrated development of urban and rural passenger transport is the inevitability of the times, and it is the needs of China′s new urbanization development. Through the understanding of integration of urban and rural public transportation, the article analyzed the difference between the road passenger trans-port and public transport. Then it proposed key technologies of the urban and rural transit integrated plan-ning which are establishment of integrated rural hub system, integrated urban and rural public transporta-tion network structure, integration of urban and rural bus fare and sustainable public transport subsidy mechanism. At the same time, it studied the content of each key technology with cases.%统筹城乡客运发展是时代发展的必然性,也是我国新型城镇化发展的现实需要,通过对城乡公交一体化内涵的理解,对公路客运和公共交通之间差异性进行分析,提出城乡公交一体化规划关键技术,包括建立城乡一体的枢纽体系、城乡一体的线网结构、城乡一体票价体系和可持续的公交补贴机制,并结合案例对每项关键技术进行研究。

  13. New method to solve collusion attack and key collision in combined public key%解决组合公钥共谋攻击和密钥碰撞的新方法

    Institute of Scientific and Technical Information of China (English)

    LI Fang-wei; MA An-jun; ZHU Jiang; YU Hang

    2014-01-01

    The purpose of this paper is to solve the problem of collusion attack and key collision in combined public key crypto-system. First, for the linear collusion attacks, this paper proposed a new method to construct seed matrix, it made the sum of seeds gre%以解决组合公钥体制中共谋攻击和密钥碰撞问题为目的。首先,针对线性共谋攻击,提出了一种新的构造种子矩阵的方法,使得种子密钥和大于基点加法群的阶数,从而使密钥之间不能相互线性表示。其次在密钥的生产过程中,引入系数破坏了层不同和层互斥不同的关系,为解决选择共谋攻击提供了一种有效的方法,同时增强了抵御随机共谋攻击的能力。最后,在密钥产生的流程中,通过公钥对比来避免密钥碰撞,为解决密钥碰撞问题提出了一种新方法。

  14. CRYPTOGRAPHIC SECURE CLOUD STORAGE MODEL WITH ANONYMOUS AUTHENTICATION AND AUTOMATIC FILE RECOVERY

    Directory of Open Access Journals (Sweden)

    Sowmiya Murthy

    2014-10-01

    Full Text Available We propose a secure cloud storage model that addresses security and storage issues for cloud computing environments. Security is achieved by anonymous authentication which ensures that cloud users remain anonymous while getting duly authenticated. For achieving this goal, we propose a digital signature based authentication scheme with a decentralized architecture for distributed key management with multiple Key Distribution Centers. Homomorphic encryption scheme using Paillier public key cryptosystem is used for encrypting the data that is stored in the cloud. We incorporate a query driven approach for validating the access policies defined by an individual user for his/her data i.e. the access is granted to a requester only if his credentials matches with the hidden access policy. Further, since data is vulnerable to losses or damages due to the vagaries of the network, we propose an automatic retrieval mechanism where lost data is recovered by data replication and file replacement with string matching algorithm. We describe a prototype implementation of our proposed model.

  15. A Certificate Authority (CA-based cryptographic solution for HIPAA privacy/security regulations

    Directory of Open Access Journals (Sweden)

    Sangram Ray

    2014-07-01

    Full Text Available The Health Insurance Portability and Accountability Act (HIPAA passed by the US Congress establishes a number of privacy/security regulations for e-healthcare systems. These regulations support patients’ medical privacy and secure exchange of PHI (protected health information among medical practitioners. Three existing HIPAA-based schemes have been studied but appear to be ineffective as patients’ PHI is stored in smartcards. Moreover, carrying a smartcard during a treatment session and accessing PHI from different locations results in restrictions. In addition, authentication of the smartcard presenter would not be possible if the PIN is compromised. In this context, we propose an MCS (medical center server should be located at each hospital and accessed via the Internet for secure handling of patients’ PHI. All entities of the proposed e-health system register online with the MCS, and each entity negotiates a contributory registration key, where public-key certificates issued and maintained by CAs are used for authentication. Prior to a treatment session, a doctor negotiates a secret session key with MCS and uploads/retrieves patients’ PHI securely. The proposed scheme has five phases, which have been implemented in a secure manner for supporting HIPAA privacy/security regulations. Finally, the security aspects, computation and communication costs of the scheme are analyzed and compared with existing methods that display satisfactory performance.

  16. An Experimental Study of Cryptography Capability using Chained Key Exchange Scheme for Embedded Devices

    OpenAIRE

    2014-01-01

    After 38 years of birthday Diffie-Hellman Key Exchange (DHKE), there are many proposed improvements in the DHKE protocol to encounter modern security issues. This protocol seems quite simple to be implemented, but it can be vulnerable to many types of attacks. In this work, we propose the Chained Key Exchange scheme as a case study to explore cryptographic computation capability of embedded microcontroller. We choose ARM RaspberryPi board as hardware platform for experimental setup. To enable...

  17. Design and Analysis of Optimization Algorithms to Minimize Cryptographic Processing in BGP Security Protocols.

    Science.gov (United States)

    Sriram, Vinay K; Montgomery, Doug

    2017-07-01

    The Internet is subject to attacks due to vulnerabilities in its routing protocols. One proposed approach to attain greater security is to cryptographically protect network reachability announcements exchanged between Border Gateway Protocol (BGP) routers. This study proposes and evaluates the performance and efficiency of various optimization algorithms for validation of digitally signed BGP updates. In particular, this investigation focuses on the BGPSEC (BGP with SECurity extensions) protocol, currently under consideration for standardization in the Internet Engineering Task Force. We analyze three basic BGPSEC update processing algorithms: Unoptimized, Cache Common Segments (CCS) optimization, and Best Path Only (BPO) optimization. We further propose and study cache management schemes to be used in conjunction with the CCS and BPO algorithms. The performance metrics used in the analyses are: (1) routing table convergence time after BGPSEC peering reset or router reboot events and (2) peak-second signature verification workload. Both analytical modeling and detailed trace-driven simulation were performed. Results show that the BPO algorithm is 330% to 628% faster than the unoptimized algorithm for routing table convergence in a typical Internet core-facing provider edge router.

  18. A secure and efficient cryptographic hash function based on NewFORK-256

    Directory of Open Access Journals (Sweden)

    Harshvardhan Tiwari

    2012-11-01

    Full Text Available Cryptographic hash functions serve as a fundamental building block of information security and are used in numerous security applications and protocols such as digital signature schemes, construction of MAC and random number generation, for ensuring data integrity and data origin authentication. Researchers have noticed serious security flaws and vulnerabilities in most widely used MD and SHA family hash functions. As a result hash functions from FORK family with longer digest value were considered as good alternatives for MD5 and SHA-1, but recent attacks against these hash functions have highlighted their weaknesses. In this paper we propose a dedicated hash function MNF-256 based on the design principle of NewFORK-256. It takes 512 bit message blocks and generates 256 bit hash value. A random sequence is added as an additional input to the compression function of MNF-256. Three branch parallel structure and secure compression function make MNF-256 an efficient, fast and secure hash function. Various simulation results indicate that MNF-256 is immune to common cryptanalytic attacks and faster than NewFORK-256.

  19. Disinvestment policy and the public funding of assisted reproductive technologies: outcomes of deliberative engagements with three key stakeholder groups.

    Science.gov (United States)

    Hodgetts, Katherine; Hiller, Janet E; Street, Jackie M; Carter, Drew; Braunack-Mayer, Annette J; Watt, Amber M; Moss, John R; Elshaug, Adam G

    2014-05-05

    Measures to improve the quality and sustainability of healthcare practice and provision have become a policy concern. In addition, the involvement of stakeholders in health policy decision-making has been advocated, as complex questions arise around the structure of funding arrangements in a context of limited resources. Using a case study of assisted reproductive technologies (ART), deliberative engagements with a range of stakeholder groups were held on the topic of how best to structure the distribution of Australian public funding in this domain. Deliberative engagements were carried out with groups of ART consumers, clinicians and community members. The forums were informed by a systematic review of ART treatment safety and effectiveness (focusing, in particular, on maternal age and number of treatment cycles), as well as by international policy comparisons, and ethical and cost analyses. Forum discussions were transcribed and subject to thematic analysis. Each forum demonstrated stakeholders' capacity to understand concepts of choice under resource scarcity and disinvestment, and to countenance options for ART funding not always aligned with their interests. Deliberations in each engagement identified concerns around 'equity' and 'patient responsibility', culminating in a broad preference for (potential) ART subsidy restrictions to be based upon individual factors rather than maternal age or number of treatment cycles. Community participants were open to restrictions based upon measures of body mass index (BMI) and smoking status, while consumers and clinicians saw support to improve these factors as part of an ART treatment program, as distinct from a funding criterion. All groups advocated continued patient co-payments, with measures in place to provide treatment access to those unable to pay (namely, equity of access). Deliberations yielded qualitative, socially-negotiated evidence required to inform ethical, accountable policy decisions in the specific

  20. Experimental quantum key distribution with source flaws

    Science.gov (United States)

    Xu, Feihu; Wei, Kejin; Sajeed, Shihan; Kaiser, Sarah; Sun, Shihai; Tang, Zhiyuan; Qian, Li; Makarov, Vadim; Lo, Hoi-Kwong

    2015-09-01

    Decoy-state quantum key distribution (QKD) is a standard technique in current quantum cryptographic implementations. Unfortunately, existing experiments have two important drawbacks: the state preparation is assumed to be perfect without errors and the employed security proofs do not fully consider the finite-key effects for general attacks. These two drawbacks mean that existing experiments are not guaranteed to be proven to be secure in practice. Here, we perform an experiment that shows secure QKD with imperfect state preparations over long distances and achieves rigorous finite-key security bounds for decoy-state QKD against coherent attacks in the universally composable framework. We quantify the source flaws experimentally and demonstrate a QKD implementation that is tolerant to channel loss despite the source flaws. Our implementation considers more real-world problems than most previous experiments, and our theory can be applied to general discrete-variable QKD systems. These features constitute a step towards secure QKD with imperfect devices.

  1. 一种基于多变量公钥的软件注册方案%A SOFTWARE REGISTRATION SCHEME BASED ON MULTIVARIATE PUBLIC KEY

    Institute of Scientific and Technical Information of China (English)

    黄宁

    2013-01-01

    对中间域多变量公钥密码算法MFE(Medium-Field Multivariate Public Key Encryption)可能遇到的奇异性进行分析和处理,并研究其应用于软件注册。用改进的MFE多变量公钥密码算法,在扩展ASCⅡ字符集构建的有限域F(28)中,设计软件注册方案,运算过程多处采用了不可更改的机器指纹信息,实现一次一密,为了提高安全性,在注册码的形成过程中对字符进行分解;而在注册码的验证过程中对字符进行合成,抗代数攻击能力得到提高。由于注册码对机器指纹信息的依赖,有效防止多机共享注册码。%We analyse and process the singularity which might be encountered by MFE(medium-field multivariate public key encryption)and study the application of it in software registration.We use the enhanced MFE multivariate public key encryption to design a software registration scheme in finite field F (28 )configured from the character set of extended ASCII,which uses unchangeable fingerprints of machine in several steps of operation,and realises one key used for just one time.In order to enhance the security,characters are decomposed in the process of registration string generation,and then are composed in the process of registration string verification,thus the ability to withstand the algebraic attacks is enhanced. The dependence of registration string on machine fingerprints effectively prevents any registration string from being shared by multiple machines.

  2. 基于广域特征关联的公钥高深度加密方案%Method of Public-Key Deep Encryption Based on Public Characteristic Correlation

    Institute of Scientific and Technical Information of China (English)

    赵晓津

    2014-01-01

    研究基于广域特征关联的标准模型下伪装网络入侵容忍公钥高深度加密方案,提出一种基于特征关联的公钥加密方案,通过对入侵网络数据进行特征分析的方法,提取入侵数据的原始特征,在此基础上,通过特征关联的方法对公钥进行加密,大大提高了破解难度;采用一段随机的文本进行性能测试,结果显示,与传统加密方案相比较,所提加密方案具有更高的加密深度和解密正确率,且加密后文本容量较小,基本不影响系统处理和传输,具有很好的应用价值。%Study on the method of public-key deep encryption in standard intrusion tolerant model. A method of public-key encryption in standard intrusion tolerant model was proposed, the input data was analyzed with characteristic extrac-tion, and then, the public-key encryption was done with characteristic correlation, and with which, it was more difficult to break. A random text in this paper was taken as target to test the ability of encrypting and breaking, the result shows that compared with traditional method, the new method has a higher ability for encryption and a higher rate of break, the text size after encryption is similar with original, so it does not affect the process and transmission, it will be applied widely.

  3. Implications for alcohol minimum unit pricing advocacy: what can we learn for public health from UK newsprint coverage of key claim-makers in the policy debate?

    Science.gov (United States)

    Hilton, Shona; Wood, Karen; Patterson, Chris; Katikireddi, Srinivasa Vittal

    2014-02-01

    On May 24th 2012, Scotland passed the Alcohol (Minimum Pricing) Bill. Minimum unit pricing (MUP) is an intervention that raises the price of the cheapest alcohol to reduce alcohol consumption and related harms. There is a growing literature on industry's influence in policymaking and media representations of policies, but relatively little about frames used by key claim-makers in the public MUP policy debate. This study elucidates the dynamic interplay between key claim-makers to identify lessons for policy advocacy in the media in the UK and internationally. Content analysis was conducted on 262 articles from seven UK and three Scottish national newspapers between 1st May 2011 and 31st May 2012, retrieved from electronic databases. Advocates' and critics' constructions of the alcohol problem and MUP were examined. Advocates depicted the problem as primarily driven by cheap alcohol and marketing, while critics' constructions focused on youth binge drinkers and dependent drinkers. Advocates justified support by citing the intervention's targeted design, but critics denounced the policy as illegal, likely to encourage illicit trade, unsupported by evidence and likely to be ineffective, while harming the responsible majority, low-income consumers and businesses. Critics' arguments were consistent over time, and single statements often encompassed multiple rationales. This study presents advocates with several important lessons for promoting policies in the media. Firstly, it may be useful to shift focus away from young binge drinkers and heavy drinkers, towards population-level over-consumption. Secondly, advocates might focus on presenting the policy as part of a wider package of alcohol policies. Thirdly, emphasis on the success of recent public health policies could help portray the UK and Scotland as world leaders in tackling culturally embedded health and social problems through policy; highlighting past successes when presenting future policies may be a valuable

  4. Audio Information Hiding Algorithm Based on Knapsack Public-key%一种基于背包公钥的语音信息隐藏算法

    Institute of Scientific and Technical Information of China (English)

    付喜辉; 丁文龙

    2011-01-01

    针对在传榆语音秘密信息过程中存在破坏或窃取的问题,提出一种鲁棒性较强的信息隐藏方法.把一段语言作为秘密信息隐藏到宿主音频中,在公共信道中传递秘密信息.该算法是根据人类听觉系统在小波域中嵌入秘密信息,并且利用背包公钥可以使隐藏的信息具有加密功能.对于外界的噪声、压缩、滤波干扰有很强的抗干扰能力.%Secret audio message has to experience all kinds of attacks during transporting. This paper presents a steganography algorithm with strong robustness. It embeds a speech as the secret message into original audio signal, and transmits the secret message in the public channel. The algorithm makes use of Human Auditory System (HAS) characteristics and embeds secret message in the wavelet domain. With knapsack public-key, the algorithm not only encrypts the hiding information but also encrypting the information. It also has strong anti-disturbance ability against noise, compression and filter.

  5. 电子选举中的安全协议%Cryptographic Protocols for Electronic Voting

    Institute of Scientific and Technical Information of China (English)

    孟江涛; 冯登国; 胡振宇

    2002-01-01

    Electronic Voting has begun to move into the mainstream, with small online votes taking place on the Internet. Electronic Voting investigates how to conduct large-scale electronic Voting securely including various modes of voting. In this paper we will discuss the characteristics of a good Electronic Voting system and explore cryptographic Protocols that can be used to build actual implementations with these characteristics. We mainly study the Electronic Voting protocols as opposed to the Electronic Voting systems. We propose some new taxonomy of the security protocols proposed for Electronic Voting procedures and examine their advantages and shortcomings. The goal of the paper is to impose some order into the multitude of Electronic Voting mechanisms that would lead to a better understanding of challenges in the Electronic Voting field. In the end, we give some advices on Electronic Voting system design.%随着因特网上出现的一些小范围的电子选举,电子选举开始引起人们的关注.而电子选举中的关键技术之一是电子选举协议的设计,特别是在多种投票方式下大规模电子选举协议的安全性问题.讨论了优秀的电子投票系统应该具备的特点,及如何通过密码协议来实现这些特点;对电子选举协议提出了新的分类方法,并考察了其优缺点;并对已有的许多电子选举协议进行了分类整理,有助于人们更好地理解这一领域内所面临的挑战和问题;同时对电子选举系统的设计也给出了一些建议.

  6. Hybrid cryptography key management.

    Energy Technology Data Exchange (ETDEWEB)

    Draelos, Timothy John; Torgerson, Mark Dolan; Neumann, William Douglas; Gallup, Donald R.; Collins, Michael Joseph; Beaver, Cheryl Lynn

    2003-11-01

    Wireless communication networks are highly resource-constrained; thus many security protocols which work in other settings may not be efficient enough for use in wireless environments. This report considers a variety of cryptographic techniques which enable secure, authenticated communication when resources such as processor speed, battery power, memory, and bandwidth are tightly limited.

  7. Hybrid cryptography key management.

    Energy Technology Data Exchange (ETDEWEB)

    Draelos, Timothy John; Torgerson, Mark Dolan; Neumann, William Douglas; Gallup, Donald R.; Collins, Michael Joseph; Beaver, Cheryl Lynn

    2003-11-01

    Wireless communication networks are highly resource-constrained; thus many security protocols which work in other settings may not be efficient enough for use in wireless environments. This report considers a variety of cryptographic techniques which enable secure, authenticated communication when resources such as processor speed, battery power, memory, and bandwidth are tightly limited.

  8. Pairing-Free ID-Based Key-Insulated Signature Scheme

    Institute of Scientific and Technical Information of China (English)

    Guo-Bin Zhu; Hu Xiong; Zhi-Guang Qin

    2015-01-01

    Abstract⎯Without the assumption that the private keys are kept secure perfectly, cryptographic primitives cannot be deployed in the insecure environments where the key leakage is inevitable. In order to reduce the damage caused by the key exposure in the identity-based (ID-based) signature scenarios efficiently, we propose an ID-based key-insulated signature scheme in this paper, which eliminates the expensive bilinear pairing operations. Compared with the previous work, our scheme minimizes the computation cost without any extra cost. Under the discrete logarithm (DL) assumption, a security proof of our scheme in the random oracle model has also been given.

  9. Secure Biometric Key Generation Scheme for Cryptography using Combined Biometric Features of Fingerprint and Iris

    Directory of Open Access Journals (Sweden)

    Mr.P.Balakumar

    2011-09-01

    Full Text Available Exact and automatic recognition and authentication of users are a essential difficulty in all systems. Shared secrets like Personal Identification Numbers or Passwords and key devices such as Smart cards are not presently sufficient in few situations. What is required is a system that could authenticate that the person is actually the person. The biometrics is improving the capability to recognize the persons. The usage of biometrics system permits the recognition of a living person according to the physiological features or behavioral features to be recognized without human involvement. This leads to the world wide usage of biometrics to secure the system. The various biometrics used in securing system are fingerprint, iris, retina, etc. The construction of cryptographic key from biometrics is used generally to secure the system. The efficiency and the flexibility of the cryptographic make it suitable for securing purpose. In some times, biometrics can be stolen; this makes the attackers to access the system for any time. This problem is diminished in this paper by using two biometrics features. The biometrics used in this paper is fingerprint and iris. These two features are combined with the help of fusion algorithm. From the combined features, cryptographic key is generated. The experimental result shows that the proposed techniques results in better security than the existing techniques.

  10. Group key management

    Energy Technology Data Exchange (ETDEWEB)

    Dunigan, T.; Cao, C.

    1997-08-01

    This report describes an architecture and implementation for doing group key management over a data communications network. The architecture describes a protocol for establishing a shared encryption key among an authenticated and authorized collection of network entities. Group access requires one or more authorization certificates. The implementation includes a simple public key and certificate infrastructure. Multicast is used for some of the key management messages. An application programming interface multiplexes key management and user application messages. An implementation using the new IP security protocols is postulated. The architecture is compared with other group key management proposals, and the performance and the limitations of the implementation are described.

  11. Key distribution in PKC through Quantas

    CERN Document Server

    Goel, Aditya

    2010-01-01

    Cryptography literally means "The art & science of secret writing & sending a message between two parties in such a way that its contents cannot be understood by someone other than the intended recipient". and Quantum word is related with "Light". Thus, Quantum Cryptography is a way of descripting any information in the form of quantum particles. There are no classical cryptographic systems which are perfectly secure. In contrast to Classical cryptography which depends upon Mathematics, Quantum Cryptography utilizes the concepts of Quantum Physics which provides us the security against the cleverest marauders of the present age. In the view of increasing need of Network and Information Security, we do require methods to overcome the Molecular Computing technologies (A future technology) and other techniques of the various codebrakers. Both the parts i.e. Quantum Key distribution and Information transference from Sender to Receiver are much efficient and secure. It is based upon BB84 protocol. It can b...

  12. Evaluation of unique identifiers used as keys to match identical publications in Pure and SciVal – a case study from health science [version 2; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Heidi Holst Madsen

    2016-09-01

    Full Text Available Unique identifiers (UID are seen as an effective key to match identical publications across databases or identify duplicates in a database. The objective of the present study is to investigate how well UIDs work as match keys in the integration between Pure and SciVal, based on a case with publications from the health sciences. We evaluate the matching process based on information about coverage, precision, and characteristics of publications matched versus not matched with UIDs as the match keys. We analyze this information to detect errors, if any, in the matching process. As an example we also briefly discuss how publication sets formed by using UIDs as the match keys may affect the bibliometric indicators number of publications, number of citations, and the average number of citations per publication.  The objective is addressed in a literature review and a case study. The literature review shows that only a few studies evaluate how well UIDs work as a match key. From the literature we identify four error types: Duplicate digital object identifiers (DOI, incorrect DOIs in reference lists and databases, DOIs not registered by the database where a bibliometric analysis is performed, and erroneous optical or special character recognition. The case study explores the use of UIDs in the integration between the databases Pure and SciVal. Specifically journal publications in English are matched between the two databases. We find all error types except erroneous optical or special character recognition in our publication sets. In particular the duplicate DOIs constitute a problem for the calculation of bibliometric indicators as both keeping the duplicates to improve the reliability of citation counts and deleting them to improve the reliability of publication counts will distort the calculation of average number of citations per publication. The use of UIDs as a match key in citation linking is implemented in many settings, and the availability of

  13. Atmospheric Quantum Key Distribution in Daylight

    Science.gov (United States)

    Buttler, William; Hughes, Richard; Morgan, George; Nordholt, Jane; Peterson, Charles

    2001-05-01

    In quantum key distribution (QKD) single-photon transmissions generate the shared, secret random number sequences, known as cryptographic keys, that are used to encrypt and decrypt secret communications. Because the security of QKD is based on principles of quantum physics an adversary can neither successfully tap the key transmissions, nor evade detection (eavesdropping raises the key error rate above a threshold value). We have developed an experimental QKD system that uses the four-state “BB84” protocol with non-orthogonal photon polarization states and lowest-order adaptive optics to generate shared key material over multi-kilometer atmospheric, line-of-sight paths. We will present results of a daylight demonstration of this system. Key material is built up using the transmission of a photon-pulse per bit of an initial secret random sequence. We will describe the design and operation of the system, present an analysis of the system's security, efficiency and error rate, and describe the prospects for longer-distance applications of free-space QKD.

  14. Ready-to-eat cereals are key sources of selected micronutrients among schoolchildren from public and private elementary schools in Quetzaltenango, Guatemala.

    Science.gov (United States)

    Montenegro-Bethancourt, Gabriela; Vossenaar, Marieke; Kuijper, Lothar D; Doak, Colleen M; Solomons, Noel W

    2009-05-01

    This cross-sectional dietary survey aimed to assess the consumption and relative nutrient contribution of ready-to-eat cereals (RTEC) among schoolchildren from 2 social classes in an urban center in the Guatemalan province of Quetzaltenango. A total of 449 24-hour dietary records were collected using a pictorial workbook registry method among third- and fourth-grade schoolchildren. The sample population was divided between low-income, public school attendants (n = 219) and students from higher-income private institutions (n = 230). We described the contribution of RTEC to estimated total energy; carbohydrates; protein; fat; vitamins A, C, and D; thiamin; riboflavin; folate; calcium; iron; and zinc over the 24-hour interval of registry. Approximately 41% of the subjects mentioned RTEC at least once in their 24-hour record; 93% of these at breakfast time. From the 7 RTEC varieties reported, 4 were presweetened. Estimated cereal consumption was significantly higher among private school participants (P < .001). The RTEC contributed 2.4% of estimated total energy across the whole sample and 3.6% of total carbohydrate; iron intake from RTEC was 21% of total, whereas less than 1% of calcium intake came from this source. Among the subgroup of cereal consumers, RTEC accounted for more than 40% of their daily recommendation intake for iron, vitamin C, thiamin, and riboflavin. The RTEC consumers had significantly higher intakes for all nutrients except carbohydrate and riboflavin as compared with nonconsumers. This study demonstrates the importance of RTEC as a key source of several selected micronutrients to schoolchildren's diet in this setting.

  15. Intelligent policy making? Key actors' perspectives on the development and implementation of an early years' initiative in Scotland's public health arena.

    Science.gov (United States)

    Deas, L; Mattu, L; Gnich, W

    2013-11-01

    Increased political enthusiasm for evidence-based policy and action has re-ignited interest in the use of evidence within political and practitioner networks. Theories of evidence-based policy making and practice are being re-considered in an attempt to better understand the processes through which knowledge translation occurs. Understanding how policy develops, and practice results, has the potential to facilitate effective evidence use. Further knowledge of the factors which shape healthcare delivery and their influence in different contexts is needed. This paper explores the processes involved in the development of a complex intervention in Scotland's National Health Service (NHS). It uses a national oral health programme for children (Childsmile) as a case study, drawing upon key actors' perceptions of the influence of different drivers (research evidence, practitioner knowledge and values, policy, and political and local context) to programme development. Framework analysis is used to analyse stakeholder accounts from in-depth interviews. Documentary review is also undertaken. Findings suggest that Childsmile can be described as an 'evidence-informed' intervention, blending available research evidence with knowledge from practitioner experience and continual learning through evaluation, to plan delivery. The importance of context was underscored, in terms of the need to align with prevailing political ideology and in the facilitative strength of networks within the relatively small public health community in Scotland. Respondents' perceptions support several existing theoretical models of translation, however no single theory offered a comprehensive framework covering all aspects of the complex processes reported. Childsmile's use of best available evidence and on-going contribution to knowledge suggest that the programme is an example of intelligent policy making with international relevance.

  16. A Novel Enhancement Technique of the Hill Cipher for Effective Cryptographic Purposes

    Directory of Open Access Journals (Sweden)

    A. F.A. Abidin

    2011-01-01

    Full Text Available Problem statement: The Hill cipher is the first polygraph cipher which has a few advantages in data encryption. However, it is vulnerable to known plaintext attack. Besides, an invertible key matrix is needed for decryption. It may become problematic since an invertible key matrix does not always exist. Approach: In this study, a robust Hill algorithm (Hill++ has been proposed. The algorithm is an extension of Affine Hill cipher. A random matrix key, RMK is introduced as an extra key for encryption. An algorithm proposed for involutory key matrix generation is also implemented in the proposed algorithm. Results: A comparative study has been made between the proposed algorithm and the existing algorithms. The encryption quality of the proposed algorithm is also measured by using the maximum deviation factor and correlation coefficient factor. Conclusion/Recommendations: The proposed algorithm introduced a random matrix key which is computed based on the previous ciphertext blocks and a multiplying factor. A modified of Hill Cipher is free from the all-zero plaintext blocks vulnerability. Usage of involutory key for encryption and decryption managed to solve the non invertible key matrix problem. It also simplify the computational complexity in term of generating the inverse key matrix.

  17. Methods of Generating Key Sequences Based on Parameters of Handwritten Passwords and Signatures

    Directory of Open Access Journals (Sweden)

    Pavel Lozhnikov

    2016-10-01

    Full Text Available The modern encryption methods are reliable if strong keys (passwords are used, but the human factor issue cannot be solved by cryptographic methods. The best variant is binding all authenticators (passwords, encryption keys, and others to the identities. When a user is authenticated by biometrical characteristics, the problem of protecting a biometrical template stored on a remote server becomes a concern. The paper proposes several methods of generating keys (passwords by means of the fuzzy extractors method based on signature parameters without storing templates in an open way.

  18. Quantum key distribution system in standard telecommunications fiber using a short wavelength single-photon source

    CERN Document Server

    Collins, R J; Fernandez, V; Gordon, K J; Makhonin, M N; Timpson, J A; Tahraoui, A; Hopkinson, M; Fox, A M; Skolnick, M S; Buller, G S; 10.1063/1.3327427

    2010-01-01

    A demonstration of the principles of quantum key distribution is performed using a single-photon source in a proof of concept test-bed over a distance of 2 km in standard telecommunications optical fiber. The single-photon source was an optically-pumped quantum dot in a microcavity emitting at a wavelength of 895 nm. Characterization of the quantum key distribution parameters was performed at a range of different optical excitation powers. An investigation of the effect of varying the optical excitation power of the quantum dot microcavity on the quantum bit error rate and cryptographic key exchange rate of the system are presented.

  19. 设计密码协议的若干原则与方法%SEVERAL PRINCIPLES AND METHODS FOR DESIGNING CRYPTOGRAPHIC PROTOCOLS

    Institute of Scientific and Technical Information of China (English)

    赵华伟; 刘月

    2011-01-01

    传统的密码协议设计主要考虑理想环境下运行的安全性.为了设计实用安全的密码协议,首先对理想环境下密码协议中存在的主要攻击进行研究和总结,提出四条协议设计原则,以避免常见的设计缺陷;然后通过对消息完整性的研究,提出一种协议转换算法,可将理想环境下安全的密码协议转换为现实环境下安全的密码协议,并证明算法的安全性.该转换算法的提出,有助于设计在现实环境下运行安全的密码协议.%Traditional cryptographic protocol design focuses mainly on the security issue in a perfect environment. In order to design practical and secure cryptographic protocols, at first the primary attacks upon cryptographic protocols in a perfect environment is studied and summarized, so that four principles for protocol design is proposed in order to avoid common design defects; next, through studying message integrity, a protocol transformation algorithm is proposed which can turn secure cryptographic protocols in a perfect environment into ones in a real environment; the security of the algorithm is validated. The proposal of the transformation algorithm is helpful to design a secure cryptographic protocol to operate in a real environment.

  20. ZooKeys, unlocking Earth’s incredible biodiversity and building a sustainable bridge into the public domain: From “print-based” to “web-based” taxonomy, systematics, and natural history. ZooKeys Editorial Opening Paper

    Directory of Open Access Journals (Sweden)

    Lyubomir Penev

    2008-07-01

    Full Text Available Publishing taxonomic and systematics studies in the digital era faces major challenges and requires new approaches, many of which are currently stimulating spirited discussions amongst taxonomists and systematists. New amendments to the International Code of Zoological Nomenclature are expected to regulate electronic publishing of new taxa and create a standard form for their registration (ZooBank. Responding to a perceived need, this editorial announces establishment of ZooKeys – a new online and print journal in zoological taxonomy and systematics, which aims to quickly respond and adapt to the newest developments in taxonomic publishing. Open Access is accepted as mandatory for ZooKeys. Th e rationale for and concept of ZooKeys is discussed in detail.

  1. ID-based Key-insulated Authenticated Key Agreement Protocol

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yuan; CHENG Xiao-ming; CHAI Zhen-chuan

    2007-01-01

    The basic idea behind an ID-based cryptosystem is that end user's public key can be determined by his identity information. Comparing with the traditional certificate-based cryptography, identity-based cryptography can eliminate much of the overhead associated with the deployment and management of certificate. However, exposure of private keys can be the most devastating attack on a public key based cryptosystem since such that all security guarantees are lost. In this paper, an ID-based authenticated key agreement protocol was presented. For solving the problem of key exposure of the basic scheme, the technique of key insulation was applied and a key insulated version is developed.

  2. 基于Swarm平台的理性密码协议建模与仿真%Modeling and Simulation of Rational Cryptographic Protocols based on Swarm

    Institute of Scientific and Technical Information of China (English)

    杨雪君; 陈宁江

    2014-01-01

    Aiming at the question of number of strategies were chosen by participants in real world when the rational cryptographic protocols running, a model and the algorithm of solving this problem is designed, which simulated the rational actions on the Swarm platform of intelligent agents. Firstly, payoff matrix was deifned in this article, and then, the state-copy formulation of participants is listed up;3 Nash Equilibrium values discovered by solving the formulation, i.e., the different value which all the participants were used to honest strategy, tactics and non honesty mixed strategy, and game algorithm is designed according to the different values; at last, each object is deifned in the main game needed on the Swarm, however, the basic object function can not fully meet rational cryptographic protocols on the Swarm, so the transformation of the Swarm platform part of the main object function given the key code transformation, the game of interaction in the whole swarm is implemented on the Swarm. As the result shows, rational participants will be dififcult to reach Nash Equilibrium through rounds of game when the pay off function is constant. However, by using incentives to encourage the proifts of honest participants, rational participants will be easy to Nash Equilibrium with less rounds of game, and the proportion of the honest participants is at least half the list. There are some reference values by using the algorithmic game theory that presents the methods which simulated on the Swarm platform for researching rational cryptographic protocols in this article.%针对现实世界中理性密码协议的参与者博弈过程不易观察和预测的问题,文章在多智能主体的仿真平台Swarm上对理性密码协议中参与者的诚实策略和非诚实策略行为进行了建模和仿真。文章首先定义了主体的收益矩阵,进一步根据收益矩阵建立了参与者在整个博弈过程中的状态复制方程;然后求解出该方程

  3. All-optical cryptography of M-QAM formats by using two-dimensional spectrally sliced keys.

    Science.gov (United States)

    Abbade, Marcelo L F; Cvijetic, Milorad; Messani, Carlos A; Alves, Cleiton J; Tenenbaum, Stefan

    2015-05-10

    There has been an increased interest in enhancing the security of optical communications systems and networks. All-optical cryptography methods have been considered as an alternative to electronic data encryption. In this paper we propose and verify the use of a novel all-optical scheme based on cryptographic keys applied on the spectral signal for encryption of the M-QAM modulated data with bit rates of up to 200 gigabits per second.

  4. A Council-based Distributed Key Management Scheme for MANETs

    Directory of Open Access Journals (Sweden)

    Mohammed ELKOUTBI

    2010-09-01

    Full Text Available Abstract—Mobile ad hoc networks (MAETs have beenproposed as an extremely flexible technology for establishingwireless communications. In comparison with fixed networks,some new security issues have arisen with the introduction ofMAETs. Secure routing, in particular, is an important andcomplicated issue. Clustering is commonly used in order to limitthe amount of secure routing information. In this work, wepropose an enhanced solution for ad hoc key management basedon a cauterized architecture. This solution uses clusters as aframework to manage cryptographic keys in a distributed way.This paper sheds light on the key management algorithm for theOLSR protocol standard. Our algorithm takes into account thenode mobility and engenders major improvements regarding thenumber of elected cluster heads to create a PKI council. Ourobjective is to distribute the certification authority functions for areduced and less mobile cluster heads that will serve for keysexchange.

  5. Quantum key distribution with an entangled light emitting diode

    Energy Technology Data Exchange (ETDEWEB)

    Dzurnak, B.; Stevenson, R. M.; Nilsson, J.; Dynes, J. F.; Yuan, Z. L.; Skiba-Szymanska, J.; Shields, A. J. [Toshiba Research Europe Limited, 208 Science Park, Milton Road, Cambridge CB4 0GZ (United Kingdom); Farrer, I.; Ritchie, D. A. [Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge CB3 0HE (United Kingdom)

    2015-12-28

    Measurements performed on entangled photon pairs shared between two parties can allow unique quantum cryptographic keys to be formed, creating secure links between users. An advantage of using such entangled photon links is that they can be adapted to propagate entanglement to end users of quantum networks with only untrusted nodes. However, demonstrations of quantum key distribution with entangled photons have so far relied on sources optically excited with lasers. Here, we realize a quantum cryptography system based on an electrically driven entangled-light-emitting diode. Measurement bases are passively chosen and we show formation of an error-free quantum key. Our measurements also simultaneously reveal Bell's parameter for the detected light, which exceeds the threshold for quantum entanglement.

  6. Quantum key distribution without detector vulnerabilities using optically seeded lasers

    Science.gov (United States)

    Comandar, L. C.; Lucamarini, M.; Fröhlich, B.; Dynes, J. F.; Sharpe, A. W.; Tam, S. W.-B.; Yuan, Z. L.; Penty, R. V.; Shields, A. J.

    2016-05-01

    Security in quantum cryptography is continuously challenged by inventive attacks targeting the real components of a cryptographic set-up, and duly restored by new countermeasures to foil them. Owing to their high sensitivity and complex design, detectors are the most frequently attacked components. It was recently shown that two-photon interference from independent light sources can be used to remove any vulnerability from detectors. This new form of detection-safe quantum key distribution (QKD), termed measurement-device-independent (MDI), has been experimentally demonstrated but with modest key rates. Here, we introduce a new pulsed laser seeding technique to obtain high-visibility interference from gain-switched lasers and thereby perform MDI-QKD with unprecedented key rates in excess of 1 megabit per second in the finite-size regime. This represents a two to six orders of magnitude improvement over existing implementations and supports the new scheme as a practical resource for secure quantum communications.

  7. Development of a New Cryptographic Construct Using Palmprint-Based Fuzzy Vault

    Directory of Open Access Journals (Sweden)

    Amioy Kumar

    2009-01-01

    Full Text Available The combination of cryptology and biometrics has emerged as promising component of information security. Despite the current popularity of palmprint biometric, there has not been any attempt to investigate its usage for the fuzzy vault. This paper therefore investigates the possible usage of palmprint in fuzzy vault to develop a user friendly and reliable crypto system. We suggest the use of both symmetric and asymmetric approach for the encryption. The ciphertext of any document is generated by symmetric cryptosystem; the symmetric key is then encrypted by asymmetric approach. Further, Reed and Solomon codes are used on the generated asymmetric key to provide some error tolerance while decryption. The experimental results from the proposed approach on the palmprint images suggest its possible usage in an automated palmprint-based key generation system.

  8. The Development of Key Performance Indicators to Monitor Early Facilities Management Performance Through the Use of BIM Technologies in Public Sector Projects

    OpenAIRE

    McAuley, Barry; Hore, Alan; West, Roger

    2015-01-01

    One of the biggest threats faced by governments in delivering greater efficiency on public works is the need for the public sector to have an enhanced physical environment to operate from. The physical environment can either enhance or impede worker productivity, therefore contributing to its bottom line profits and success of the organisation. This has now resulted in the AEC sector witnessing the development and adoption of Building Information Modelling (BIM), so as to ensure a new level o...

  9. A Composed Protocol of Quantum Identity Authentication Plus Quantum Key Distribution Based on Squeezed States

    Institute of Scientific and Technical Information of China (English)

    张盛; 王剑; 唐朝京; 张权

    2011-01-01

    It is established that a single quantum cryptography protocol usually cooperates with other cryptographic systems, such as an authentication system, in the real world. However, few protocols have been proposed on how to combine two or more quantum protocols. To fill this gap, we propose a composed quantum protocol, containing both quantum identity authentication and quantum key distribution, using squeezed states. Hence, not only the identity can be verified, but also a new private key can be generated by our new protocol. We also analyze the security under an optimal attack, and the efficiency, which is defined by the threshold of the tolerant error rate, using Gaussian error function.

  10. Security bound of two-bases quantum key-distribution protocols using qudits

    CERN Document Server

    Nikolopoulos, G M; Nikolopoulos, Georgios M.; Alber, Gernot

    2005-01-01

    We investigate the security bounds of quantum cryptographic protocols using $d$-level systems. In particular, we focus on schemes that use two mutually unbiased bases, thus extending the BB84 quantum key distribution scheme to higher dimensions. Under the assumption of general coherent attacks, we derive an analytic expression for the ultimate upper security bound of such quantum cryptography schemes. This bound is well below the predictions of optimal cloning machines. The possibility of extraction of a secret key beyond entanglement distillation is discussed. In the case of qutrits we argue that any eavesdropping strategy is equivalent to a symmetric one. For higher dimensions such an equivalence is generally no longer valid.

  11. Provable entanglement and information cost for qubit-based quantum key-distribution protocols

    CERN Document Server

    Nikolopoulos, G M; Khalique, A

    2005-01-01

    Provable entanglement has been shown to be a necessary precondition for unconditionally secure key generation in the context of quantum cryptographic protocols. We estimate the maximal threshold disturbance up to which the two legitimate users can prove the presence of quantum correlations in their data, in the context of the four- and six-state quantum key-distribution protocols, under the assumption of coherent attacks. Moreover, we investigate the conditions under which an eavesdropper can saturate these bounds, by means of incoherent and two-qubit coherent attacks. A direct connection between entanglement distillation and classical advantage distillation is also presented.

  12. Linear Distinguishers in the Key-less Setting: Application to PRESENT

    DEFF Research Database (Denmark)

    Lauridsen, Martin Mehl; Rechberger, Christian

    2015-01-01

    The application of the concept of linear cryptanalysis to the domain of key-less primitives is largely an open problem. In this paper we, for the first time, propose a model in which its application is meaningful for distinguishing block ciphers. Combining our model with ideas from message...... modification and rebound-like approaches, we initiate a study of cryptographic primitives with respect to this new attack vector and choose the lightweight block cipher PRESENT as an example target. This leads to known-key distinguishers over up to 27 rounds, whereas the best previous result is up to 18 rounds...

  13. Design of cryptographically secure AES like S-Box using second-order reversible cellular automata for wireless body area network applications.

    Science.gov (United States)

    Gangadari, Bhoopal Rao; Rafi Ahamed, Shaik

    2016-09-01

    In biomedical, data security is the most expensive resource for wireless body area network applications. Cryptographic algorithms are used in order to protect the information against unauthorised access. Advanced encryption standard (AES) cryptographic algorithm plays a vital role in telemedicine applications. The authors propose a novel approach for design of substitution bytes (S-Box) using second-order reversible one-dimensional cellular automata (RCA(2)) as a replacement to the classical look-up-table (LUT) based S-Box used in AES algorithm. The performance of proposed RCA(2) based S-Box and conventional LUT based S-Box is evaluated in terms of security using the cryptographic properties such as the nonlinearity, correlation immunity bias, strict avalanche criteria and entropy. Moreover, it is also shown that RCA(2) based S-Boxes are dynamic in nature, invertible and provide high level of security. Further, it is also found that the RCA(2) based S-Box have comparatively better performance than that of conventional LUT based S-Box.

  14. Symmetric-key cryptosystem with DNA technology

    Institute of Scientific and Technical Information of China (English)

    LU MingXin; LAI XueJia; XIAO GuoZhen; QIN Lei

    2007-01-01

    DNA cryptography is a new field which has emerged with progress in the research of DNA computing. In our study, a symmetric-key cryptosystem was designed by applying a modern DNA biotechnology, microarray, into cryptographic technologies. This is referred to as DNA symmetric-key cryptosystem (DNASC). In DNASC,both encryption and decryption keys are formed by DNA probes, while its ciphertext is embedded in a specially designed DNA chip (microarray). The security of this system is mainly rooted in difficult biology processes and problems, rather than conventional computing technology, thus it is unaffected by changes from the attack of the coming quantum computer. The encryption process is a fabrication of a specially designed DNA chip and the decryption process is the DNA hybridization.In DNASC, billions of DNA probes are hybridized and identified at the same time,thus the decryption process is conducted in a massive, parallel way. The great potential in vast parallelism computation and the extraordinary information density of DNA are displayed in DNASC to some degree.

  15. A Matter of Trust: Ten Key Insights from Recent Public Opinion Research on Attitudes about Education among Hispanic Parents, Students and Young Adults

    Science.gov (United States)

    Gasbarra, Paul; Johnson, Jean

    2008-01-01

    In many respects, Hispanic families share the aspirations and anxieties of many other families nationwide: They are keenly focused on the role completing high school and going to college will play in their children's future. Students and young adults see success in school and college as key to interesting work and a prosperous future, and most are…

  16. PUBLIC KEY ENCRYPTION WITH MULTI-KEYWORD SEARCH BASED ON IPE%基于内积加密的支持多关键字检索的公钥加密方案

    Institute of Scientific and Technical Information of China (English)

    刘蓬涛

    2013-01-01

    Public-key encryption with multi-keyword search (PEMKS) is the extension of the public-key encryption with keyword search (PEKS),it can support the receiver to search all subsets of keywords embedded in the ciphertext.In this paper,we construct a PEMKS scheme by using inner-product encryption (IPE) scheme aiming at the problems of multi-keyword search in public key encryption as well as ciphertext length,and give the security analysis on it.%支持多关键字检索的公钥加密(PEMKS)是支持关键字检索的公钥加密(PEKS)的扩展,能够支持接收者对嵌入密文中的所有关键字的子集进行检索.针对公钥加密中的多关键字检索以及密文长度问题,利用内积加密方案构造一个支持多关键字检索的公钥加密方案并给出安全性分析.

  17. Key Statistics on Public Elementary and Secondary Education Reported by State and by Regional, Locale, and Wealth Clusters, 1987-88. Survey Report.

    Science.gov (United States)

    Davis, Jo Ann

    Regional and subregional division characteristics of public elementary and secondary education in the United States are reported. Characteristics associated with urbanicity and wealth are also reported. Factors examined are those most commonly used to identify the resources, needs, organization, and special characteristics of education within each…

  18. Key points of ifre protection analysis of public places of entertainment%公共娱乐场所的消防防火要点分析

    Institute of Scientific and Technical Information of China (English)

    张伟

    2015-01-01

    Now the number of public places of entertainment is increasing.When people relax in public places,they will ignore the safety hazard.This article will start with the definition and characteristics of public entertainment,analyze and study the hidden fire hazards,and put forward the fire prevention and fire prevention and management measures,in order to provide reference and reference for the elimination of public entertainment places.%现在公共娱乐场所数量与日俱增。人们在公共娱乐场所放松时,会忽视安全隐患。本文将从公共娱乐场所界定及其火灾特点入手,分析和研究公共场所存在的火灾隐患,最后提出消防防火要点及管理措施,以期为消除公共娱乐场所安全隐患提供参考和借鉴。

  19. Systematic Management of Change Is the Key to Successful Staff Development. An Initial Study of the Bloomfield Public Schools Staff Development Project. Teacher Essentials, Styles & Strategies (TESS).

    Science.gov (United States)

    Celso, Nicholas; Morris, Harold

    Confronted by a maturing staff, lower teacher turnover rates, declining enrollments, and more sophisticated instructional methods, the Bloomfield (New Jersey) Public School District adopted an ambitious staff development initiative in 1983. This paper describes the planning and implementation strategies used to launch Bloomfield's Teaching…

  20. Systematic Management of Change Is the Key to Successful Staff Development. An Initial Study of the Bloomfield Public Schools Staff Development Project. Teacher Essentials, Styles & Strategies (TESS).

    Science.gov (United States)

    Celso, Nicholas; Morris, Harold

    Confronted by a maturing staff, lower teacher turnover rates, declining enrollments, and more sophisticated instructional methods, the Bloomfield (New Jersey) Public School District adopted an ambitious staff development initiative in 1983. This paper describes the planning and implementation strategies used to launch Bloomfield's Teaching…

  1. Algorithm for finding partitionings of hard variants of boolean satisfiability problem with application to inversion of some cryptographic functions.

    Science.gov (United States)

    Semenov, Alexander; Zaikin, Oleg

    2016-01-01

    In this paper we propose an approach for constructing partitionings of hard variants of the Boolean satisfiability problem (SAT). Such partitionings can be used for solving corresponding SAT instances in parallel. For the same SAT instance one can construct different partitionings, each of them is a set of simplified versions of the original SAT instance. The effectiveness of an arbitrary partitioning is determined by the total time of solving of all SAT instances from it. We suggest the approach, based on the Monte Carlo method, for estimating time of processing of an arbitrary partitioning. With each partitioning we associate a point in the special finite search space. The estimation of effectiveness of the particular partitioning is the value of predictive function in the corresponding point of this space. The problem of search for an effective partitioning can be formulated as a problem of optimization of the predictive function. We use metaheuristic algorithms (simulated annealing and tabu search) to move from point to point in the search space. In our computational experiments we found partitionings for SAT instances encoding problems of inversion of some cryptographic functions. Several of these SAT instances with realistic predicted solving time were successfully solved on a computing cluster and in the volunteer computing project SAT@home. The solving time agrees well with estimations obtained by the proposed method.

  2. Two New Approaches for Secured Image Steganography Using Cryptographic Techniques and Type Conversions

    Directory of Open Access Journals (Sweden)

    Sujay Narayana

    2011-02-01

    Full Text Available The science of securing a data by encryption is Cryptography whereas the method of hiding secretmessages in other messages is Steganography, so that the secret’s very existence is concealed. The term‘Steganography’ describes the method of hiding cognitive content in another medium to avoid detectionby the intruders. This paper introduces two new methods wherein cryptography and steganography arecombined to encrypt the data as well as to hide the encrypted data in another medium so the fact that amessage being sent is concealed. One of the methods shows how to secure the image by converting it intocipher text by S-DES algorithm using a secret key and conceal this text in another image bysteganographic method. Another method shows a new way of hiding an image in another image byencrypting the image directly by S-DES algorithm using a key image and the data obtained is concealedin another image. The proposed method prevents the possibilities of steganalysis also.

  3. Pre-Mrna Introns as a Model for Cryptographic Algorithm:. Theory and Experiments

    Science.gov (United States)

    Regoli, Massimo

    2010-01-01

    The RNA-Crypto System (shortly RCS) is a symmetric key algorithm to cipher data. The idea for this new algorithm starts from the observation of nature. In particular from the observation of RNA behavior and some of its properties. In particular the RNA sequences have some sections called Introns. Introns, derived from the term "intragenic regions", are non-coding sections of precursor mRNA (pre-mRNA) or other RNAs, that are removed (spliced out of the RNA) before the mature RNA is formed. Once the introns have been spliced out of a pre-mRNA, the resulting mRNA sequence is ready to be translated into a protein. The corresponding parts of a gene are known as introns as well. The nature and the role of Introns in the pre-mRNA is not clear and it is under ponderous researches by Biologists but, in our case, we will use the presence of Introns in the RNA-Crypto System output as a strong method to add chaotic non coding information and an unnecessary behaviour in the access to the secret key to code the messages. In the RNA-Crypto System algorithm the introns are sections of the ciphered message with non-coding information as well as in the precursor mRNA.

  4. A Secure Key Distribution System of Quantum Cryptography Based on the Coherent State

    Science.gov (United States)

    Guo, Guang-Can; Zhang, Xiao-Yu

    1996-01-01

    The cryptographic communication has a lot of important applications, particularly in the magnificent prospects of private communication. As one knows, the security of cryptographic channel depends crucially on the secrecy of the key. The Vernam cipher is the only cipher system which has guaranteed security. In that system the key must be as long as the message and most be used only once. Quantum cryptography is a method whereby key secrecy can be guaranteed by a physical law. So it is impossible, even in principle, to eavesdrop on such channels. Quantum cryptography has been developed in recent years. Up to now, many schemes of quantum cryptography have been proposed. Now one of the main problems in this field is how to increase transmission distance. In order to use quantum nature of light, up to now proposed schemes all use very dim light pulses. The average photon number is about 0.1. Because of the loss of the optical fiber, it is difficult for the quantum cryptography based on one photon level or on dim light to realize quantum key-distribution over long distance. A quantum key distribution based on coherent state is introduced in this paper. Here we discuss the feasibility and security of this scheme.

  5. Key Theories from Critical Medical Anthropology for Public Health Research. Part II: Medicine in the Social System, Medicine as a Social System

    Directory of Open Access Journals (Sweden)

    Jennifer J. Carroll

    2014-06-01

    Full Text Available This article summarizes four significant theoretical concepts from the field of Critical Medical Anthropology in two parts: in the first part, biopower/discipline and explanatory models; in the second, structural violence, and identity politics and biological citizenship. The four subjects reviewed here have been chosen for their importance to our understanding of human behaviors related to health and illness, as well as for the impact that they can have on theory, research, and practice in the field of public health. These critical theories can provide new ways of thinking about professional roles, medical decisions, disease diagnosis and etiology, treatment adherence, prevention messaging, and all sorts of health-related behaviors and systems of understanding. They can also help public health researchers shed light on the human beliefs and activities that shape patterns of disease within and across populations. Whether a research question is being formulated or research findings are being analyzed, the critical social theories outlined here can foster a more holistic understanding of the human element in any public health project.

  6. Keyed shear joints

    DEFF Research Database (Denmark)

    Hansen, Klaus

    This report gives a summary of the present information on the behaviour of vertical keyed shear joints in large panel structures. An attemp is made to outline the implications which this information might have on the analysis and design of a complete wall. The publications also gives a short...

  7. Wireless Physical Layer Security: On the Performance Limit of Secret-Key Agreement

    KAUST Repository

    Zorgui, Marwen

    2015-05-01

    Physical layer security (PLS) is a new paradigm aiming at securing communications between legitimate parties at the physical layer. Conventionally, achieving confidentiality in communication networks relies on cryptographic techniques such as public-key cryptography, secret-key distribution and symmetric encryption. Such techniques are deemed secure based on the assumption of limited computational abilities of a wiretapper. Given the relentless progress in computational capacities and the dynamic topology and proliferation of modern wireless networks, the relevance of the previous techniques in securing communications is more and more questionable and less and less reliable. In contrast to this paradigm, PLS does not assume a specific computational power at any eavesdropper, its premise to guarantee provable security via employing channel coding techniques at the physical layer exploiting the inherent randomness in most communication systems. In this dissertation, we investigate a particular aspect of PLS, which is secret-key agreement, also known as secret-sharing. In this setup, two legitimate parties try to distill a secret-key via the observation of correlated signals through a noisy wireless channel, in the presence of an eavesdropper who must be kept ignorant of the secret-key. Additionally, a noiseless public channel is made available to the legitimate parties to exchange public messages that are also accessible to the eavesdropper. Recall that key agreement is an important aspect toward realizing secure communications in the sense that the key can be used in a one-time pad scheme to send the confidential message. In the first part, our focus is on secret-sharing over Rayleigh fading quasi-static channels. We study the fundamental relationship relating the probability of error and a given target secret-key rate in the high power regime. This is characterized through the diversity multiplexing tradeoff (DMT) concept, that we define for our model and then

  8. Completely device-independent quantum key distribution

    Science.gov (United States)

    Aguilar, Edgar A.; Ramanathan, Ravishankar; Kofler, Johannes; Pawłowski, Marcin

    2016-08-01

    Quantum key distribution (QKD) is a provably secure way for two distant parties to establish a common secret key, which then can be used in a classical cryptographic scheme. Using quantum entanglement, one can reduce the necessary assumptions that the parties have to make about their devices, giving rise to device-independent QKD (DIQKD). However, in all existing protocols to date the parties need to have an initial (at least partially) random seed as a resource. In this work, we show that this requirement can be dropped. Using recent advances in the fields of randomness amplification and randomness expansion, we demonstrate that it is sufficient for the message the parties want to communicate to be (partially) unknown to the adversaries—an assumption without which any type of cryptography would be pointless to begin with. One party can use her secret message to locally generate a secret sequence of bits, which can then be openly used by herself and the other party in a DIQKD protocol. Hence our work reduces the requirements needed to perform secure DIQKD and establish safe communication.

  9. DNA-based cryptographic methods for data hiding in DNA media.

    Science.gov (United States)

    Marwan, Samiha; Shawish, Ahmed; Nagaty, Khaled

    2016-12-01

    Information security can be achieved using cryptography, steganography or a combination of them, where data is firstly encrypted using any of the available cryptography techniques and then hid into any hiding medium. Recently, the famous genomic DNA has been introduced as a hiding medium, known as DNA steganography, due to its notable ability to hide huge data sets with a high level of randomness and hence security. Despite the numerous cryptography techniques, to our knowledge only the vigenere cipher and the DNA-based playfair cipher have been combined with the DNA steganography, which keeps space for investigation of other techniques and coming up with new improvements. This paper presents a comprehensive analysis between the DNA-based playfair, vigenere, RSA and the AES ciphers, each combined with a DNA hiding technique. The conducted analysis reports the performance diversity of each combined technique in terms of security, speed, hiding capacity in addition to both key size and data size. Moreover, this paper proposes a modification of the current combined DNA-based playfair cipher technique, which makes it not only simple and fast but also provides a significantly higher hiding capacity and security. The conducted extensive experimental studies confirm such outstanding performance in comparison with all the discussed combined techniques. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. An update on the side channel cryptanalysis of MACs based on cryptographic hash functions

    DEFF Research Database (Denmark)

    Gauravaram, Praveen; Okeya, Katsuyuki

    2007-01-01

    into consideration. Next, we propose new hybrid NMAC/HMAC schemes for security against side channel attacks assuming that their underlying block cipher is ideal. We then show that M-NMAC, MDx-MAC and a variant of the envelope MAC scheme based on DM with an ideal block cipher are secure against DPA attacks.......Okeya has established that HMAC/NMAC implementations based on only Matyas-Meyer-Oseas (MMO) PGV scheme and his two refined PGV schemes are secure against side channel DPA attacks when the block cipher in these constructions is secure against these attacks. The significant result of Okeya's analysis...... is that the implementations of HMAC/NMAC with the Davies-Meyer (DM) compression function based hash functions such as MD5 and SHA-1 are vulnerable to side channel attacks. In this paper, first we show a partial key recovery attack on NMAC/HMAC based on Okeya's two refined PGV schemes by taking practical constraints...

  11. Teaching design discussion of trivium cryptographic algorithm%Trivium密码算法的教学设计探讨

    Institute of Scientific and Technical Information of China (English)

    韦永壮; 张润莲

    2012-01-01

      Trivium cipher algorithm is ultimately one of the selected algorithm of the European Stream Cipher Scheme ( eSTREAM ). Because of its following characteristic such as simple, graceful, fast software and hardware, security and so on, in academia and industry,it was widely payed attention to. According to existed actual problems of Trivium cryptographic algorithm in the teaching and the characteristics of the students in senior information profession, the structure of Trivium algorithm analyzed, the teaching design were put forward from the view of Boolean function, valuable teaching ideas were provided for peer.%  Trivium密码算法是欧洲流密码计划(eSTREAM)的最终入选算法之一。由于其结构简洁、优美、软硬件实现快速、安全性好等特点,倍受学术界和工业界的广泛关注。针对Trivium密码算法实际教学中存在的问题及信息专业高年级学生的特点,分析了Trivium算法的结构,提出从布尔函数的角度来进行教学设计,包括算法部件分析、加解密过程、性能及安全性等环节,为同行提供有价值的教学思路。

  12. Research capacity and culture of the Victorian public health allied health workforce is influenced by key research support staff and location.

    Science.gov (United States)

    Williams, Cylie; Miyazaki, Koki; Borkowski, Donna; McKinstry, Carol; Cotchet, Matthew; Haines, Terry

    2015-06-01

    The aim of the present study was to identify and understand the self-rated research capacity and culture of the allied health workforce. METHODS. The present study was a cross-sectional survey. The Research Capacity and Culture tool was disseminated to all Victorian public health allied health departments. General demographic data were also collected, including the presence of an organisational allied health research lead. Five hundred and twenty fully completed surveys were returned by participants; all allied health disciplines and all grades were represented. One hundred and eighty-six participants had an organisational allied health research lead and 432 were located in a metropolitan-based health service. There were significant differences (P organisational and team research skills between those with and without a research lead, together with those in different service locations (metropolitan vs non-metropolitan). Higher self-ratings in individual research skills (P organisational level has a flow-down effect on research capacity and culture.

  13. 卫生应急关键技术筛选框架设计与结果分析*%Research on the Framework Design of Selecting Key Techniques of Public Health Emergency Response and the Analysis of Results

    Institute of Scientific and Technical Information of China (English)

    吴群红; 胥娇; 郝艳华; 宁宁

    2013-01-01

      目的:探讨卫生应急关键技术概念、内涵、筛选框架、原则及方法。方法:运用头脑风暴法及专题讨论法,构建卫生应急关键技术筛选框架,通过议题小组法明确卫生应急关键技术筛选标准,运用德尔菲法筛选关键技术。结果:设计了基于突发公共卫生事件分类、生命周期处置流程、技术层次、技术范畴的四维卫生应急关键技术研究框架,通过平均算术法和秩和法筛选了包括一级、二级技术在内的9大类共59项基层迫切需要的卫生应急关键技术集。结论:卫生应急关键技术的框架设计和筛选方法具有科学性、实用性和可操作性,研究可为今后进一步遴选、研究和开发关键技术提供概念框架和工具指南。%Objective: To explore the concept, connotation, selection framework, principles and methods of selecting the key techniques of health emergency. Methods: By using method of brainstorming and focused group discussion, the framework of selecting the key techniques of public health emergency was constructed, the criteria for key techniques selection was developed through nominal group discussion method;then a set of key techniques were identified through nominal group discussion method. Results:The framework for selecting key techniques was designed based on four dimensions: the classification of emergency events, life cycle of emergency response, level of techniques and technique category; based on the results of arithmetic average and rank sum method, 59 key techniques out of 9 types were selected. Conclusion: Selection framework and method of public health emergency key techniques are scientific, feasible, and applicable, which provide the conceptual framework and guideline for further research.

  14. 基于McEliece公钥密码体制的盲签名算法研究%Blind Signature Scheme Based on McEliece Public Key Cryptosystem

    Institute of Scientific and Technical Information of China (English)

    赵程程; 李子臣; 刘念; 阎晓妲

    2012-01-01

    Due to the threat of quantum computer on public - key cryptography, the public key cryptosystems against quantum computing has become the focus of research in information security field. A blind sig- nature based on McEliece public key cryptography was proposed aiming at protecting of consumers'anonymi- ty. By Hash on a message and blind process ensure signed message and behavior cannot be linked. At the same time the signature of receiver's identity is kept secret and will never be leaked out, with unconditional intractability and security for this kind of blind signature is analyzed. Result shows that this model has the advantages of inheriting the security of McEliece public-key cryptography, having the general basic proper- ties of digital signatures and blind signatures, resisting quantum computer attack and eventually has a very strong security.%由于量子计算机对现用公钥密码体制的威胁,抵抗量子计算的公钥密码体制已经成为信息安全领域研究的重点。针对消费者的匿名性保护问题,本文提出一种基于McEliece公钥密码体制的盲签名算法。通过对消息进行Hash,盲化和去盲过程,保证签名的消息与签署行为不可链接,且永远不会被泄露,具有无条件不可追踪性。文章还对这种盲签名的安全性进行分析,分析结果表明,此模型既继承了McEliece公钥密码体制的安全性,能抵抗量子计算机的攻击,也具有一般数字签名和盲签名的基本性质,具有很强的安全性。

  15. Propuesta de aplicación de un sistema de Infraestructura de Clave Pública (Public Key Infrastructure "PKI" y los Certificados Digitales en la trazabilidad de productos agrícolas

    Directory of Open Access Journals (Sweden)

    Juan Carlos Sepúlveda Peña

    2009-01-01

    Full Text Available Hoy día la trazabilidad de los productos y las actividades en la cadena de suministro se han convertido en un nuevo factor a tener en cuenta en la cadena de distribución de alimentos y la agroindustria. Cada vez más, consumidores en muchas partes del mundo demandan de pruebas verificables de trazabilidad como uno criterio importante de la calidad / inocuidad de los productos alimenticios. El presente artículo propone una solución a esta problemática introduciendo el uso de un sistema de Infraestructura de Clave Pública (Public Key Infrastructure "PKI" y los certificados digitales (CD.

  16. Health statistics - Key data on health 2002 (Data 1970-2001 Luxembourg: Office for Official Publications of the European Communities,2002

    Directory of Open Access Journals (Sweden)

    Antonio G. de Belvis

    2004-06-01

    Full Text Available

    Since 1990s, the European institutions have been discussing on the importance to establish a Health
    Indicators Monitoring System.

    This system would: undertake a “critical review of existing health data and indicators; develop appropriate methods for the collection of the progressively comparable health data needed to establish these indicators; develop a reliable system for the transfer and sharing of health data and indicators, essentially by means of the telematic interchange of data; identify methods and tools required for conducting analyses and producing reports on state of health, trends and determinants, and the impact of health-related policies” (according to the speech made by the European Commission representative, Mr. Frédéric Sicard, during the former EUPHA Conference held in Rome, last November.
    These are the outcomes of the Health statistics — Key data on health 2002, issued on March 8th 2004 and prepared by the Office for National Statistics (ONS, United Kingdom, and the sector ‘Health and safety’, of Unit E.3 (Education, health and culture of Eurostat, on behalf of the European Commission.

  17. Time-Dependent Cryptographic Protocol Logic and Its Formal Semantics%时间相关密码协议逻辑及其形式化语义

    Institute of Scientific and Technical Information of China (English)

    雷新锋; 刘军; 肖军模

    2011-01-01

    在密码协议中,主体的认知与信仰状态是随时间推移而不断变化的.为了在协议分析中体现这种动态性,提出一种时间相关密码协议逻辑.该逻辑基于谓词模态逻辑,通过在谓词及模态词中引入时间参数以体现时间因素,使得逻辑可表达各个主体在协议不同时间点的行为、知识及信仰.给出该逻辑的形式化语义,在避免逻辑语言二义性的同时保证了逻辑的可靠性.该语义基于Kripke结构,将可能世界建立在主体局部世界与时间局部世界的基础上,使得任一可能世界能够反映协议的一个可能的全过程.该逻辑为密码协议,特别是时间相关密码协议提供了灵活的分析方法,增强了基于逻辑方法的协议分析能力.%In cryptographic protocols, the agent's epistemic and doxastic states are changeable over time. To model these dynamics, a time-dependent cryptographic protocol logic is proposed. Our logic is based on the predicate modal logic and the time factor can be expressed in it by invoking a time variable as a parameter of predicates and modal operators. This makes it possible to model every agent's actions, knowledges and beliefs at different time points. We also give the formal semantics of our logic to avoid the ambiguity of its language and make the logic sound. The semantics is based on the kripke structure and the possible world in it is built both on the local world of agent and the specific world of time. This makes every possible world can give a global view of each point of the protocol. Our logic provides a flexible method for analyzing the cryptographic protocols, especially the time-dependent cryptographic protocols, and increases the power of the logical method for analyzing protocols.

  18. Depth keying

    Science.gov (United States)

    Gvili, Ronen; Kaplan, Amir; Ofek, Eyal; Yahav, Giora

    2003-05-01

    We present a new solution to the known problem of video keying in a natural environment. We segment foreground objects from background objects using their relative distance from the camera, which makes it possible to do away with the use of color for keying. To do so, we developed and built a novel depth video camera, capable of producing RGB and D signals, where D stands for the distance to each pixel. The new RGBD camera enables the creation of a whole new gallery of effects and applications such as multi-layer background substitutions. This new modality makes the production of real time mixed reality video possible, as well as post-production manipulation of recorded video. We address the problem of color spill -- in which the color of the foreground object is mixed, along its boundary, with the background color. This problem prevents an accurate separation of the foreground object from its background, and it is most visible when compositing the foreground objects to a new background. Most existing techniques are limited to the use of a constant background color. We offer a novel general approach to the problem with enabling the use of the natural background, based upon the D channel generated by the camera.

  19. Promoting awareness of key resources for evidence-informed decision making in public health: An evaluation of a webinar series about knowledge translation methods and tools

    Directory of Open Access Journals (Sweden)

    Jennifer eYost

    2016-04-01

    awareness and stimulating use of resources for evidence-informed decision making and knowledge translation in public health practice.

  20. Promoting Awareness of Key Resources for Evidence-Informed Decision-making in Public Health: An Evaluation of a Webinar Series about Knowledge Translation Methods and Tools.

    Science.gov (United States)

    Yost, Jennifer; Mackintosh, Jeannie; Read, Kristin; Dobbins, Maureen

    2016-01-01

    stimulating use of resources for evidence-informed decision-making and knowledge translation in public health practice.

  1. Public verifiable multi-signcryption scheme%可公开验证的多重签密方案

    Institute of Scientific and Technical Information of China (English)

    陈军; 刘锋; 高伟

    2011-01-01

    签密技术能在一个逻辑步骤内同时实现签名和加密两项功能,相比较以往的“先签名后加密”有较高的效率.克服张键红等人提出的多重签密模型的不足,构造了一个新的多重签密方案.该方案的优点:安全性上实现了消息的保密性、不可否认性、可公开验证性、前向安全性,能抗合谋攻击,安全性能高;签密算法和验证算法复杂度小,灵活性好;方案简洁易于实际操作.%Signcryption is a new cryptographic technology,which simultaneously fulfills both the function of digital signature and public key encryption in a logically single step, and more efficient than the traditional "signature followed by encryption" approach.The paper points out the weakness of the previous signcryption scheme proposed by ZHANG Jianhong et al., and constructs a new signcryption scheme.The new scheme provides message confidentiality,non-repudiation,forward secrecy, and public verifiability.So,it is simple and can be set up easily.

  2. Public-key Encryption Based on Extending Discrete Chebyshev Polynomials' Definition Domain to Real Number%基于实数域扩散离散Chebyshev多项式的公钥加密算法

    Institute of Scientific and Technical Information of China (English)

    陈宇; 韦鹏程

    2011-01-01

    将Chebyshev多项式与模运算相结合,对其定义在实数域上进行了扩展,经过理论验证和数据分析,总结出实数域多项式应用于公钥密码的一些性质.利用RSA公钥算法和EIGamal公钥算法的算法结构,提出基于有限域离散Chebyshev多项式的公钥密码算法.该算法结构类似于RSA算法,其安全性基于大数因式分解的难度或者与El-Gamal的离散对数难度相当,能够抵抗对于RSA的选择密文攻击,并且易于软件实现.%By combining Chebyshev polynomials with modulus compute,extending Chebyshev polynomials' definition domain to real number, some conclusions were drawn by theoretic verification and data analysis. Making use of the framework of the traditional public-key algorithm RSA and ElGamal, proposed a chaotic public-key encryption algorithm based on extending discrete Chebyshev polynomials' definition domain to Real number. Its security is based on the intractability of the integer factorization problem as RSA,and it is able to resist the chosen cipher-text attack against RSA and easy to be implemented.

  3. Free-space Quantum Key Distribution over 10 km in Daylight and at Night

    Science.gov (United States)

    Hughes, Richard; Nordholt, Jane; Peterson, Charles

    2002-05-01

    In quantum key distribution (QKD) single-photon transmissions transfer the shared, secret random number sequences, known as cryptographic keys that are used to encrypt and decrypt secret communications. Because the security of QKD is based on principles of quantum physics and information theory an adversary can neither successfully tap the key transmissions, nor evade detection. We have performed QKD using the four-state Â"BB84Â" protocol with non-orthogonal photon polarization states across a 10-km line-of-sight path in daylight and at night [1]. We transferred secret, cryptographic quality random numbers at practical rates with security against technologically feasible eavesdropping strategies. By relating the secrecy capacity (secret bits transferred per transmitted bit), which had values up to 10-3, to properties of the atmospheric channel we are able to infer the secrecy capacity of free-space QKD under other atmospheric conditions and over other, longer transmission distances. 1. R. J. Hughes, J. E. Nordholt, D. Derkacs and C. G. Peterson, Los Alamos report LA-UR-02-449.

  4. Secure Key Management in the Cloud

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Jakobsen, Thomas Pelle; Nielsen, Jesper Buus

    2013-01-01

    We consider applications involving a number of servers in the cloud that go through a sequence of online periods where the servers communicate, separated by offline periods where the servers are idle. During the offline periods, we assume that the servers need to securely store sensitive informat......We consider applications involving a number of servers in the cloud that go through a sequence of online periods where the servers communicate, separated by offline periods where the servers are idle. During the offline periods, we assume that the servers need to securely store sensitive...... information such as cryptographic keys. Applications like this include many cases where secure multiparty computation is outsourced to the cloud, and in particular a number of online auctions and benchmark computations with confidential inputs. We consider fully autonomous servers that switch between online...... and offline periods without communicating with anyone from outside the cloud, and semi-autonomous servers that need a limited kind of assistance from outside the cloud when doing the transition. We study the levels of security one can – and cannot – obtain in this model, propose light-weight protocols...

  5. 对短公钥的基于身份数字签名算法的安全性攻击∗%Attacks on Identity-based Digital Signature Algorithm with Short Public Key

    Institute of Scientific and Technical Information of China (English)

    郑红; 范佳

    2015-01-01

    An identity-based digital signature scheme with short public key is discussed. Two kinds of attacks on this algorithm indi-cates that this algorithm could not fairly satisfy the claimed security requirement. More specifically, Type I attacker could calculate all other users′valid private keys, if he gets one user′s private key. Type II attacker is able to forge a user′s signature on any other messa-ges if he gets this user′s one signature.%研究了一个具有短公钥特征的基于身份的数字签名算法。通过两种安全性攻击,指出该算法并不满足其所声称的安全性。运用第一种攻击,如果攻击者获得某个用户私钥,则他可以计算系统内所有其他用户的合法私钥。运用第二种攻击,如果攻击者获得了某个用户的一个合法签名,则他可以伪造该用户对任意其他消息的合法签名。

  6. A trustworthy key generation prototype based on DDR3 PUF for wireless sensor networks.

    Science.gov (United States)

    Liu, Wenchao; Zhang, Zhenhua; Li, Miaoxin; Liu, Zhenglin

    2014-06-30

    Secret key leakage in wireless sensor networks (WSNs) is a high security risk especially when sensor nodes are deployed in hostile environment and physically accessible to attackers. With nowadays semi/fully-invasive attack techniques attackers can directly derive the cryptographic key from non-volatile memory (NVM) storage. Physically Unclonable Function (PUF) is a promising technology to resist node capture attacks, and it also provides a low cost and tamper-resistant key provisioning solution. In this paper, we designed a PUF based on double-data-rate SDRAM Type 3 (DDR3) memory by exploring its memory decay characteristics. We also described a prototype of 128-bit key generation based on DDR3 PUF with integrated fuzzy extractor. Due to the wide adoption of DDR3 memory in WSN, our proposed DDR3 PUF technology with high security levels and no required hardware changes is suitable for a wide range of WSN applications.

  7. A Trustworthy Key Generation Prototype Based on DDR3 PUF for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Wenchao Liu

    2014-06-01

    Full Text Available Secret key leakage in wireless sensor networks (WSNs is a high security risk especially when sensor nodes are deployed in hostile environment and physically accessible to attackers. With nowadays semi/fully-invasive attack techniques attackers can directly derive the cryptographic key from non-volatile memory (NVM storage. Physically Unclonable Function (PUF is a promising technology to resist node capture attacks, and it also provides a low cost and tamper-resistant key provisioning solution. In this paper, we designed a PUF based on double-data-rate SDRAM Type 3 (DDR3 memory by exploring its memory decay characteristics. We also described a prototype of 128-bit key generation based on DDR3 PUF with integrated fuzzy extractor. Due to the wide adoption of DDR3 memory in WSN, our proposed DDR3 PUF technology with high security levels and no required hardware changes is suitable for a wide range of WSN applications.

  8. An Identity-Based Group Key Agreement Proto col for Low-Power Mobile Devices

    Institute of Scientific and Technical Information of China (English)

    TENG Jikai; WU Chuankun

    2016-01-01

    In wireless mobile networks, group mem-bers join and leave the group frequently, a dynamic group key agreement protocol is required to provide a group of users with a shared secret key to achieve cryptographic goal. Most of previous group key agreement protocols for wireless mobile networks are static and employ traditional PKI. This paper presents an ID-based dynamic authen-ticated group key agreement protocol for wireless mobile networks. In Setup and Join algorithms, the protocol re-quires two rounds and each low-power node transmits con-stant size of messages. Furthermore, in Leave algorithm, only one round is required and none of low-power nodes is required to transmit any message, which improves the effi-ciency of the entire protocol. The protocol’s AKE-security with forward secrecy is proved under Decisional bilinear in-verse Diffie-Hellman (DBIDH) assumption. It is addition-ally proved to be contributory.

  9. On Classical and Quantum Cryptography

    CERN Document Server

    Volovich, I V; Volovich, Ya.I.

    2001-01-01

    Lectures on classical and quantum cryptography. Contents: Private key cryptosystems. Elements of number theory. Public key cryptography and RSA cryptosystem. Shannon`s entropy and mutual information. Entropic uncertainty relations. The no cloning theorem. The BB84 quantum cryptographic protocol. Security proofs. Bell`s theorem. The EPRBE quantum cryptographic protocol.

  10. Obfuscation for Cryptographic Purposes

    NARCIS (Netherlands)

    D. Hofheinz (Dennis); J. Malone-Lee; M. Stam; S. Vadhan

    2007-01-01

    textabstractAn obfuscation of a function F should satisfy two requirements: firstly, using it should be possible to evaluate F; secondly, should not reveal anything about F that cannot be learnt from oracle access to F. Several definitions for obfuscation exist. However, most of them are either

  11. Enhanced OneTime Pad Cipher with MoreArithmetic and Logical Operations with Flexible Key Generation Algorithm

    Directory of Open Access Journals (Sweden)

    S.G.Srikantaswamy

    2011-12-01

    Full Text Available The process of exchanging information is called Communication. The basic Communication system involvestransmitter, receiver and the channel. The data transmitted by the sender reaches receiver through thechannel. The unauthorized parties (cracker,hacker, eavesdropper, or attacker should not be able to access the information at the channel. Therefore transmitting data securely from the sender to the receiver is a very important aspect. A cryptographic system is unconditionally secure if the cipher text produced by the system does not contain enough information to determine uniquely the corresponding plaintext, no matter how much cipher text is available. A cryptographic system is said to be computationally secure if the cost of breaking the cipher exceeds the value of the encrypted information and the time required to break the cipher exceeds the useful lifetime of the content. One time pad system can be called as unconditionally secure algorithm, if the keys (pad usedare truly random in nature. In this paper, we are demonstrating that one-time pad can be used as an efficient encryption scheme by involving arithmetic and logical operations. Here we proposed a new key generation technique, to generate a key of any length just by providing a seed value, to encrypt the message. The problem generating key value has been solved by the use of key generation algorithm.

  12. Autonomous open-source hardware apparatus for quantum key distribution

    Directory of Open Access Journals (Sweden)

    Ignacio H. López Grande

    2016-01-01

    Full Text Available We describe an autonomous, fully functional implementation of the BB84 quantum key distribution protocol using open source hardware microcontrollers for the synchronization, communication, key sifting and real-time key generation diagnostics. The quantum bits are prepared in the polarization of weak optical pulses generated with light emitting diodes, and detected using a sole single-photon counter and a temporally multiplexed scheme. The system generates a shared cryptographic key at a rate of 365 bps, with a raw quantum bit error rate of 2.7%. A detailed description of the peripheral electronics for control, driving and communication between stages is released as supplementary material. The device can be built using simple and reliable hardware and it is presented as an alternative for a practical realization of sophisticated, yet accessible quantum key distribution systems. Received: 11 Novembre 2015, Accepted: 7 January 2016; Edited by: O. Martínez; DOI: http://dx.doi.org/10.4279/PIP.080002 Cite as: I H López Grande, C T Schmiegelow, M A Larotonda, Papers in Physics 8, 080002 (2016

  13. New Public Key Certificate Revocation Scheme Based on One-way Hash Chain%基于单向散列链的公钥证书撤销机制

    Institute of Scientific and Technical Information of China (English)

    李景峰; 潘恒; 祝跃飞

    2006-01-01

    证书撤销是公钥基础设施(PKI,Public Key Infrastructure)研究和应用的难点问题.本文首先讨论了当前应用最广泛的两类证书撤销机制-证书撤销列表(CRL, Certificate Revocation List)和在线证书状态协议(OCSP, Online Certificate Status Protocol),剖析了这两种机制各自存在的不足.在此基础上,提出了一种基于单向散列链的证书撤销机制.

  14. PMI-based MIMO OFDM PHY Integrated Key Exchange (P-MOPI) Scheme

    CERN Document Server

    Lan, Pang-Chang; Lee, Chia-Han; Yeh, Ping-Cheng; Cheng, Chen-Mou

    2011-01-01

    In the literature, J.-P. Cheng et al. have proposed the MIMO-OFDM PHY integrated (MOPI) scheme for achieving physical-layer security in practice without using any cryptographic ciphers. The MOPI scheme uses channel sounding and physical-layer network coding (PNC) to prevent eavesdroppers from learning the channel state information (CSI). Nevertheless, due to the use of multiple antennas for PNC at transmitter and beamforming at receiver, it is not possible to have spatial multiplexing nor use space-time codes in our previous MOPI scheme. In this paper, we propose a variant of the MOPI scheme, called P-MOPI, that works with a cryptographic cipher and utilizes precoding matrix index (PMI) as an efficient key-exchange mechanism. With channel sounding, the PMI is only known between the transmitter and the legal receiver. The shared key can then be used, e.g., as the seed to generate pseudo random bit sequences for securing subsequent transmissions using a stream cipher. By applying the same techniques at independ...

  15. New QC-LDPC codes based Niederreiter cryptography scheme by using dual public-key%基于QC-LD PC码的双公钥 Niederreiter密码方案

    Institute of Scientific and Technical Information of China (English)

    李冲; 韩益亮

    2016-01-01

    As an important research ofpost-quantum cryptography,code-based cryptography had excellent characteristics of low complexity and high security.With the code-based cryptosystem as the core knowledge,we constructed a new QC-LDPC codes based Niederreiter cryptography scheme by using dual public-key.And the safety analysis shows that the new scheme not only resists the common method of attack,but also meets the IND-CCA2 security.The analysis of performance of the scheme is also given.We can get the conclusions that public key sizes reduce by 63%and the information rate increase by 47%.%基于编码的公钥密码体制作为抗量子攻击密码理论的重要研究内容,具有加/解密复杂性低和安全性高的优异特性。针对Niederreiter公钥密码体制进行了研究,利用QC-LDPC码和双公钥的相关知识构造了一种新的Niederreiter加密方案。安全性分析表明,加密方案能抵抗常见攻击方法的同时满足随机预言机模型下的IND-CCA2安全。最后对方案的性能进行分析,较原有Niederreiter密码的公钥量减少63%和信息率提高47%的结论。

  16. ClaimChain: decentralized public key infrastructure

    OpenAIRE

    Kulynych, Bogdan

    2017-01-01

    La infraestructura de clave pública (PKI) es un componente necesario para el funcionamiento de las comunicaciones seguras modernas. Esta infraestructura permite a los miembros participantes establecer claves criptográficas para sus destinatarios, manteniendo relaciones de alta integridad entre usuarios (nombres, direcciones u otros identificadores) y las claves públicas utilizadas para cifrar y verificar los mensajes. Los sistemas PKI existentes presentan diferentes concesio...

  17. Approximate Public Key Authentication with Information Hiding

    Energy Technology Data Exchange (ETDEWEB)

    THOMAS,EDWARD V.; DRAELOS,TIMOTHY J.

    2000-10-01

    This paper describes a solution for the problem of authenticating the shapes of statistically variant gamma spectra while simultaneously concealing the shapes and magnitudes of the sensitive spectra. The shape of a spectrum is given by the relative magnitudes and positions of the individual spectral elements. Class-specific linear orthonormal transformations of the measured spectra are used to produce output that meet both the authentication and concealment requirements. For purposes of concealment, the n-dimensional gamma spectra are transformed into n-dimensional output spectra that are effectively indistinguishable from Gaussian white noise (independent of the class). In addition, the proposed transformations are such that statistical authentication metrics computed on the transformed spectra are identical to those computed on the original spectra.

  18. Anonymity-Preserving Public-Key Encryption

    DEFF Research Database (Denmark)

    Kohlweiss, Markulf; Maurer, Ueli; Onete, Cristina

    2013-01-01

    A receiver-anonymous channel allows a sender to send a message to a receiver without an adversary learning for whom the message is intended. Wireless broadcast channels naturally provide receiver anonymity, as does multi-casting one message to a receiver population containing the intended receive...

  19. METADATA DRIVEN EFFICIENT KEY GENERATION AND DISTRIBUTION IN CLOUD SECURITY

    Directory of Open Access Journals (Sweden)

    R. Anitha

    2014-01-01

    Full Text Available With rapid development of cloud computing to a greater extent IT industries outsource their sensitive data at cloud data storage location. To keep the stored data confidential against untrusted cloud service providers, a natural way is to store only encrypted data in the cloud severs and providing an efficient access control mechanism using a competent cipher key-Cmxn, which is becoming a promising cryptographic solution. In this proposed model the cipher key is generated based on attributes of metadata. The key problems of this approach includes, the generation of cipher key-Cmxn and establishing an access control mechanism for the encrypted data using cipher key, where keys cannot be revoked without the involvement of data owner and the Metadata Data Server (MDS, hence makes data owner feels comfortable about the data stored. From this study, we propose a novel Metadata driven efficient key generation and distribution policies for cloud data security system by exploiting the characteristic of the metadata stored. Our design enforces security by providing two novel features. 1. Generation of Cipher key-Cmxn using modified feistel network, which holds good for the avalanche effect as each round of the feistel function, depends on the previous round. 2. A novel key distribution policy is designed where the encryption and decryption keys cannot be compromised without the involvement of data owner and the Metadata Data Server (MDS, hence makes data owner comfortable about the data stored. We have implemented a security model that incorporates our ideas and evaluated the performance and scalability of the secured model.

  20. 基于RO模型的公钥加密方案安全性分析与证明%Analysis and Proving of the Security on Public Key Scheme Based on RO Model

    Institute of Scientific and Technical Information of China (English)

    黄贻望; 袁科; 杨英杰

    2012-01-01

    Information Security is the fundamentality of the security society,but the cryptography is the key technology of information seCurity, so the security of design and application to crypto scheme or protocol becomes the most focus issue for people.First,this paper introduction the RO model,correlation induction judgement and define adversary model,then analyzing and proving the security of the scheme of public key with this model,and achieved the expectation result.%信息安全是信息社会存在的根基,而密码学是信息安全技术的核心部分,因此,对密码方案或协议的设计与应用的安全性成为人们最为关注的问题。本文首先介绍随机预言模型(RO)及相关的归约论断和敌手模型定义,并运用这种模型对公钥加密方案进行了安全性分析,同时给出了证明,结果达到预期的安全性目标。

  1. Anticollusion Attack Noninteractive Security Hierarchical Key Agreement Scheme in WHMS

    Directory of Open Access Journals (Sweden)

    Kefei Mao

    2016-01-01

    Full Text Available Wireless Health Monitoring Systems (WHMS have potential to change the way of health care and bring numbers of benefits to patients, physicians, hospitals, and society. However, there are crucial barriers not only to transmit the biometric information but also to protect the privacy and security of the patients’ information. The key agreement between two entities is an essential cryptography operation to clear the barriers. In particular, the noninteractive hierarchical key agreement scheme becomes an attractive direction in WHMS because each sensor node or gateway has limited resources and power. Recently, a noninteractive hierarchical key agreement scheme has been proposed by Kim for WHMS. However, we show that Kim’s cryptographic scheme is vulnerable to the collusion attack if the physicians can be corrupted. Obviously, it is a more practical security condition. Therefore, we proposed an improved key agreement scheme against the attack. Security proof, security analysis, and experimental results demonstrate that our proposed scheme gains enhanced security and more efficiency than Kim’s previous scheme while inheriting its qualities of one-round communication and security properties.

  2. Efficient Quantum Key Distribution

    CERN Document Server

    Ardehali, M; Chau, H F; Lo, H K

    1998-01-01

    We devise a simple modification that essentially doubles the efficiency of a well-known quantum key distribution scheme proposed by Bennett and Brassard (BB84). Our scheme assigns significantly different probabilities for the different polarization bases during both transmission and reception to reduce the fraction of discarded data. The actual probabilities used in the scheme are announced in public. As the number of transmitted signals increases, the efficiency of our scheme can be made to approach 100%. The security of our scheme (against single-photon eavesdropping strategies) is guaranteed by a refined analysis of accepted data which is employed to detect eavesdropping: Instead of lumping all the accepted data together to estimate a single error rate, we separate the accepted data into various subsets according to the basis employed and estimate an error rate for each subset individually. Our scheme is the first quantum key distribution with an efficiency greater than 50%. We remark that our idea is rath...

  3. Security assurance capability assessment based on entropy weight method for cryptographic module%基于熵权法的密码模块安全保障能力评估

    Institute of Scientific and Technical Information of China (English)

    粟登银; 徐开勇; 高杨

    2012-01-01

    To solve the problems that the index value of cryptographic modules is not fixed, the index system is hardly built, and the security assurance ability can not be quantitatively assessed, a security assurance capability assessment for cryptographic module was proposed. The description on indexes by interval number was applied to illustrate the security attribute of cryptographic modules. This paper determined the weight vector of each period point by entropy weight coefficient method combined with expert decision weight method. According to the interval multi-attribute decision methodology, a feasible methodology was adopted to solve the interval Information Assurance ( IA) capability evaluation problem of cryptographic modules. Finally, through analyzing two kinds of cryptographic modules, the experimental results show that the proposed method is feasible.%针对密码模块这类信息安全产品指标值不固定、指标系统难以建立、安全保障能力难以定量评估的问题,提出了一种定量描述密码模块安全保障能力的可行方法.方法运用区间数描述密码模块的安全属性,采用熵权法结合主观赋权法确定每个安全属性的权重值,运用区间型多属性决策方法进行综合评价,最后运用所提方法对两种商用密码模块进行了实例分析,计算结果表明所提方法可行.

  4. Unique Physically Anchored Cryptographic Theoretical Calculation of the Fine-Structure Constant {\\alpha} Matching both the g/2 and Interferometric High-Precision Measurements

    CERN Document Server

    Rhodes, Charles Kirkham

    2010-01-01

    The fine-structure constant {\\alpha}, the dimensionless number that represents the strength of electromagnetic coupling in the limit of sufficiently low energy interactions, is the crucial fundamental physical parameter that governs a nearly limitless range of phenomena involving the interaction of radiation with materials. Ideally, the apparatus of physical theory should be competent to provide a calculational procedure that yields a quantitatively correct value for {\\alpha} and the physical basis for its computation. This study presents the first demonstration of an observationally anchored theoretical procedure that predicts a unique value for {\\alpha} that stands in full agreement with the best (~370 ppt) high-precision experimental determinations. In a directly connected cryptographic computation, the method that gives these results also yields the magnitude of the cosmological constant {\\Omega}{\\Lambda} in conformance with the observational data and the condition of perfect flatness ({\\Omega}{\\Lambda} +...

  5. Authenticated Key Agreement in Group Settings

    Institute of Scientific and Technical Information of China (English)

    LI Ming; WANG Yong; GU Da-wu; BAI Ying-cai

    2006-01-01

    An enhanced definition of implicit key authentication and a secure group key agreement scheme from pairings are presented. This scheme combines the merits of group public key and key trees to achieve a communication-efficient and authenticated group key agreement protocol. Besides, it avoids dependence on signature or MAC by involving member's long-term keys and short-term keys in the group key. Furthermore, the idea behind this design can be employed as a general approach to extend the authenticated two-party Diffie-Hellman protocols to group settings.

  6. 公共制造云服务平台架构及其支撑技术研究%Research of structure and key technologies for public manufacturing cloud service platform

    Institute of Scientific and Technical Information of China (English)

    张倩; 齐德昱

    2013-01-01

    To make small and medium enterprises(SME) fully enjoy the benefits brought by the cloud manufacturing,this paper analyzed the operating principle of public manufacturing cloud,and proposed the structure of public manufacturing cloud service platform for the SME,as well as its formal description.It discussed several key technologies such as cloud manufacturing resource management,collaborative design,and QoS management.Based on the multi-level hierarchical control structure,it constructed a cloud manufacturing resource management and monitoring model.It also built a service-oriented virtual collaborative design environment based on the infrastructure of the platform,which could support the design of complex product.The operation model of the platform shows that the proposed platform is applicable and exemplary.%为了能使量大面广的中小企业充分享受云制造的益处,分析了公共制造云的运行原理,搭建了一个面向中小企业的公共制造云服务平台架构,并给出了其形式化描述.对平台所涉及的关键支撑技术如云制造资源管理、协同设计及QoS管理进行分析,提出了基于多级递阶控制结构的云制造资源管理与监控模型,以及在云制造基础设施之上构建了支持复杂产品设计、面向服务的虚拟协同设计环境.最后通过公共制造云服务平台运作模型说明了平台的应用性和示范性.

  7. Reforming profit-seeking mechanism is the key to public hospital reform%破除逐利机制是公立医院改革的关键

    Institute of Scientific and Technical Information of China (English)

    钟东波

    2015-01-01

    逐利机制是我国公立医院诸多问题的总根源,破除逐利机制是公立医院改革的关键。逐利机制不是公立医院自主追求的结果,而是政府一系列政策选择的意外结果。逐利机制有三个主要环节:创收压力机制、成本放大机制和收入挂钩机制。因而,破除公立医院逐利机制也应从此三个方面着手综合施策,而改革收入挂钩机制是其中具有决定意义的环节。%The profit-seeking mechanism which has emerged as an unexpected result of a series of policy choices during the market-oriented healthcare reform is the root cause of almost all problems among the public hospi-tals, and hence the key to the public hospital reform.The mechanism is comprised by three components including the pressure mechanism to create the revenue, the enlargement mechanism to reimburse costs, and the linkage mecha-nism between employee income and hospital surplus.Therefore, a comprehensive policy package should be adopted to undertake these three aspects among which the linkage mechanism is the crucial one.

  8. 重庆市建立公共文化服务体系协调组工作的重难点%Key Points and Difficulties in Establishing Chongqing Public Cultural Service System Coordinating Group

    Institute of Scientific and Technical Information of China (English)

    彭泽明

    2014-01-01

    In order to differentiate Chongqing Public Cultural Service System Coordinating Group ( hereafter referred to as Coordinating Group) from formerly-established steering groups and bureau-level joint conferences, prompt leading departments to actually exercise their functions and perform their duties, as well as motivate relevant departments to make concerted efforts and cooperate close-ly, this paper explores the key points and difficulties in establishing the Coordinating Group such as working principles, risk aversion, main content and working procedures in order to provide refer-ences for the establishment of a harmonious, efficient, authoritative and sustaining public cultural service system in Chongqing.%为了使重庆市公共文化服务体系协调组有别于以往建立的领导小组和局际联席会议,使牵头部门切实发挥作用、履行职责,相关部门齐心协力、深度融合,本文从学理上对公共文化服务体系协调组建立的工作原则、风险规避、主要内容、工作流程四个重点、难点问题进行了初步探究,试图为重庆市建立和谐、高效、权威、持续的公共文化服务体系协调组提供借鉴和参考。

  9. Key China Energy Statistics 2012

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fino-Chen, Cecilia [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-05-01

    The China Energy Group at Lawrence Berkeley National Laboratory (LBNL) was established in 1988. Over the years the Group has gained recognition as an authoritative source of China energy statistics through the publication of its China Energy Databook (CED). The Group has published seven editions to date of the CED (http://china.lbl.gov/research/chinaenergy-databook). This handbook summarizes key statistics from the CED and is expressly modeled on the International Energy Agency’s “Key World Energy Statistics” series of publications. The handbook contains timely, clearly-presented data on the supply, transformation, and consumption of all major energy sources.

  10. Key China Energy Statistics 2011

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lu, Hongyou [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fino-Chen, Cecilia [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-01-15

    The China Energy Group at Lawrence Berkeley National Laboratory (LBNL) was established in 1988. Over the years the Group has gained recognition as an authoritative source of China energy statistics through the publication of its China Energy Databook (CED). In 2008 the Group published the Seventh Edition of the CED (http://china.lbl.gov/research/chinaenergy-databook). This handbook summarizes key statistics from the CED and is expressly modeled on the International Energy Agency’s “Key World Energy Statistics” series of publications. The handbook contains timely, clearly-presented data on the supply, transformation, and consumption of all major energy sources.

  11. 基于多变量公钥密码体制的代理重签名方案%Proxy Re-signature Scheme Based on Multivariate Public Key Cryptography

    Institute of Scientific and Technical Information of China (English)

    孙昌毅; 李益发; 斯雪明

    2012-01-01

    Almost proxy re-signature schemes are hardness of big integer factoring problem and Discrete Logarithm(DL) problem. But the quantum computer can solve this question in polynomial time, which may cause potential security risks to the schemes. This paper uses the characteristics that multivariate public key cryptography can resist quantum computer attack, to design a new proxy re-signature scheme. Theoretical analysis shows that the scheme fits internal and external security, and it is efficient.%代理重签名方案大多是基于大数分解和离散对数难题设计的,而量子计算机能在多项式时间内求解这些难题,从而给方案造成安全隐患.为此,利用多变量公钥密码体制可以抵抗量子攻击的特性,设计一个新的代理重签名方案.理论分析结果表明,该方案满足内部安全性和外部安全性,且运算效率高.

  12. 可撤销的无需安全信道带关键字搜索公钥加密方案%Revocable Secure Channel Free Public Key Encryption with Keyword Search

    Institute of Scientific and Technical Information of China (English)

    于瑞琴

    2011-01-01

    通常的密码系统IBE或者PKI都必须提供从系统中撤销用户私钥的途径,同样PEKS也应该提供撤销陷门的方式. 笔者构造了1个可高效撤销的无需安全信道带关键字搜索公钥加密方案. 在该方案中,实际更新的数量仅为关键字陷门数量的对数级,这使得它非常实用.%Any setting,PKI- or identity-based,must provide a means to revoke users from the system. Efficient revocation is a well-studied problem in the traditional PKI or identity-based setting. This paper proposes revocable secure channel free public key encryption with keyword search scheme. In the scheme,the actually updated-keywords number is only the logarithm of the number of users, which makes it very practical.

  13. 空间信息网基于证书的混合式公钥基础设施%Certificate-based hybrid public key infrastructure for space information networks

    Institute of Scientific and Technical Information of China (English)

    任方; 马建峰; 郝选文

    2012-01-01

    考察了由卫星和接入节点所构成的分层式空间信息网模型,首次提出了一种适用于该网络模型的基于证书的公钥基础设施。该模型中作为核心网络的卫星层采用分布式CA管理证书,而其他节点作为接入节点,其证书管理采用集中式CA。该模型具有很强的可扩展性和一定的安全性,适用于空间信息网复杂而多变的环境。%With the development of space communication technologies, security issues in space information networks become increasingly important. However, there has been no good solution to this problem in satellite networks. This paper investigates the layered model of space information networks, which consist infrastructure suitable for of satellites and access nodes; and proposes a certificate-based public key the this model. In this model, the Certificate Management of satellite layer uses distributed CA, and the Certificate Management of other nodes (as access nodes) uses centralized CA. The proposed mode is highly scalable and has a certain degree of safety. So it is applicable to the complex and changeable environment in space information networks.

  14. Supporting Symmetric 128-bit AES in Networked Embedded Systems: An Elliptic Curve Key Establishment Protocol-on-Chip

    Directory of Open Access Journals (Sweden)

    Roshan Duraisamy

    2007-02-01

    Full Text Available The secure establishment of cryptographic keys for symmetric encryption via key agreement protocols enables nodes in a network of embedded systems and remote agents to communicate securely in an insecure environment. In this paper, we propose a pure hardware implementation of a key agreement protocol, which uses the elliptic curve Diffie-Hellmann and digital signature algorithms and enables two parties, a remote agent and a networked embedded system, to establish a 128-bit symmetric key for encryption of all transmitted data via the advanced encryption scheme (AES. The resulting implementation is a protocol-on-chip that supports full 128-bit equivalent security (PoC-128. The PoC-128 has been implemented in an FPGA, but it can also be used as an IP within different embedded applications. As 128-bit security is conjectured valid for the foreseeable future, the PoC-128 goes well beyond the state of art in securing networked embedded devices.

  15. Supporting Symmetric 128-bit AES in Networked Embedded Systems: An Elliptic Curve Key Establishment Protocol-on-Chip

    Directory of Open Access Journals (Sweden)

    Strangio MaurizioAdriano

    2007-01-01

    Full Text Available The secure establishment of cryptographic keys for symmetric encryption via key agreement protocols enables nodes in a network of embedded systems and remote agents to communicate securely in an insecure environment. In this paper, we propose a pure hardware implementation of a key agreement protocol, which uses the elliptic curve Diffie-Hellmann and digital signature algorithms and enables two parties, a remote agent and a networked embedded system, to establish a 128-bit symmetric key for encryption of all transmitted data via the advanced encryption scheme (AES. The resulting implementation is a protocol-on-chip that supports full 128-bit equivalent security (PoC-128. The PoC-128 has been implemented in an FPGA, but it can also be used as an IP within different embedded applications. As 128-bit security is conjectured valid for the foreseeable future, the PoC-128 goes well beyond the state of art in securing networked embedded devices.

  16. Proof-of-principle field test of quantum key distribution immune to detector attacks

    CERN Document Server

    Rubenok, A; Chan, P; Lucio-Martinez, I; Tittel, W

    2012-01-01

    Quantum key distribution (QKD) promises the distribution of cryptographic keys whose secrecy is guaranteed by fundamental laws of quantum physics. After more than two decades devoted to the improvement of theoretical understanding and experimental realization, recent results in quantum hacking have reminded us that the information theoretic security of QKD protocols does not necessarily imply the same level of security for actual implementations. Of particular concern are attacks that exploit vulnerabilities of single photon detectors. Here we report the first proof-of-principle demonstration of a QKD protocol that removes the threat of any such attack. Our fiber-based implementation took advantage of three different locations within the city of Calgary. Its simplicity and robustness to environment-induced property variations of deployed optical fibers, along with the enhanced level of security offered by the protocol, confirms QKD as a viable technology for safeguarding secrets in transmission.

  17. Multiplexing scheme for simplified entanglement-based large-alphabet quantum key distribution

    CERN Document Server

    Dada, Adetunmise C

    2015-01-01

    We propose a practical quantum cryptographic scheme which combines high information capacity, such as provided by high-dimensional quantum entanglement, with the simplicity of a two-dimensional Clauser-Horne-Shimony-Holt (CHSH) Bell test for security verification. By applying a state combining entanglement in a two-dimensional degree of freedom, such as photon polarization, with high-dimensional correlations in another degree of freedom, such as photon orbital angular momentum (OAM) or path, the scheme provides a considerably simplified route towards security verification in quantum key distribution (QKD) aimed at exploiting high-dimensional quantum systems for increased secure key rates. It also benefits from security against collective attacks and is feasible using currently available technologies.

  18. Two-Round Password-Only Authenticated Key Exchange in the Three-Party Setting

    Directory of Open Access Journals (Sweden)

    Junghyun Nam

    2015-01-01

    Full Text Available We present the first provably-secure three-party password-only authenticated key exchange (PAKE protocol that can run in only two communication rounds. Our protocol is generic in the sense that it can be constructed from any two-party PAKE protocol. The protocol is proven secure in a variant of the widely-accepted model of Bellare, Pointcheval and Rogaway (2000 without any idealized assumptions on the cryptographic primitives used. We also investigate the security of the two-round, three-party PAKE protocol of Wang, Hu and Li (2010 and demonstrate that this protocol cannot achieve implicit key authentication in the presence of an active adversary.

  19. Enhancing E-Voting Systems By Leveraging Biometric Key Generation (Bkg

    Directory of Open Access Journals (Sweden)

    V. C. Ossai

    2013-10-01

    Full Text Available The adoption of e-voting methods in electioneering processes will effectively reduce cost as well as enhance election activities. What makes an e-voting model reliable and acceptable is its ability to properly authenticate voters and provide a secure means through which a voter can express his/her franchise. This paper therefore proposes a design of an e-voting system that leverages a Biometric Encryption scheme known as Biometric key Generation (BKG which is a secured strategy that entails using of biometrics to generate secure cryptographic keys. The main objective of this research is to improve on the already existing E-voting systems adopting a secured bio-cryptographic technique vis Biometric key Generation (BKG as well as using a secure transmission channel for confidential datasets of a voting process. This work develops a simulation model of an E-voting system which adopts relevant algorithms with emphasis on biometric key generation schemes. The simulation of a prototype model of the electronic voting system is developed using Proteus 7.6 application software. The prototype model would consist of electronic kiosk polling booths that are all networked to the state electoral collection center and collection centers that are networked to the national electoral collection center via a VPN backbone. The proposed e-voting system uses a Virtual Private Network (VPN as the means of communication between the various polling booths and collection points. The results of validation show that the proposed model facilitates the adoption of E-governance in the developing countries.

  20. Key aspects congenital infection

    Directory of Open Access Journals (Sweden)

    Yu. V. Lobzin

    2014-01-01

    Full Text Available The key questions to solve the problem of congenital infection in the Russian Federation are: using in national practice over world accepted terminology adapted to the recommendations of the World Health Organization; representation of the modern concepts of an infectious process in the classification of congenital infections; scientific development and introducing in clinical practice the «standard case definitions», applied to different congenital infections; optimization of protocols and clinical guidelines for diagnosis, treatment and prevention of congenital infections; improvement a knowledge in the infectious disease for all  pecialists involved in the risk assessment of congenital infections, manage pregnancy and children. Based on our experience and analysis of publications, the authors suggest possible solutions.