The accident, which occurred on April 26 of 1986 at the fourth unit of the Chernobyl Nuclear Power Plant in the Ukrainian Soviet Socialist Republic of the Soviet Union, was the unprecedented accident in terms of, among other things, structural damages given to the reactor, an amount of radioactive materials released to the environment, and a number of casualties resulting from the accident. Investigation and analysis of the accident were conducted at JAERI by forming the Ad hoc Committee on the Chernobyl Accident within the organization under which Task Group A was responsible for the design and characteristics of the reactor and the accident sequence and Task Group B was responsible for behavior of radioactive materials and radiological consequences to the environment. The present report is the summary of the investigations and analyses which were carried out by the committee. (author)
The Research ad hoc committee on 'Dissemination of information' of the Atomic Energy Society of Japan was held 15 times from Oct. 1970 to Mar 1973. After that, The Special ad hoc committee on 'Dissemination of information' of the Atomic Energy Society of Japan was held 115 times from Apr. 1973 to Mar 2009. The history of these two committees is described. Activity report is arranged including the information on change of the member and topics of the meeting, and the minutes. Furthermore, the document list on International Nuclear Information System (INIS) from Japan is included. (author)
Atherton, Tim; Barthelemy, Ramon; Garmon, Savannah; Reeves, Kyle; APS Ad-Hoc Committee on LGBT Issues Team
Following the presentation of the findings and recommendations of the APS Ad-Hoc Committee on LGBT Issues (C-LGBT) by Committee Chair Michael Falk, a panel discussion will be held featuring several members of the committee. The discussion will focus on how APS can best ensure the recommendations of the committee are carried out in a timely fashion and other ideas on future APS efforts toward LGBT inclusion in physics. Discussion topics will also include the research and other input that shaped the committee's findings and recommendations.
Barr, R.; Giannotti, J.; Deuchler, W.; Scotti, R.; Stadter, J.; Walsh, J. P.; Weiss, R.
Now that the design work on the pilot plant is scheduled to start in the near future, DOE has considered it essential that an overall look be taken at the cold water pipe design process. The VSE Corporation, in its role as a support contractor to DOE, was tasked to organize a small study group to answer the question, Where do we stand on the verification of the computer models of the cold water pipe response by experimental measurements. The committee has studied all the available results of the cold water pipe development program. This report summarizes those results. The development and present capabilities of the computer programs used to calculate the response of a cold water pipe attached to a platform under known at-sea conditions are discussed. The various cold water pipe designs that have been done using the computer programs are summarized. The experiments that have been conducted up to the present time to measure the response of cold water pipes at-sea and in experimental tanks are described. The results of these experiments are presented. The experimental results are compared with the predictions made with the analytical computer programs. Conclusions drawn as a result of this analysis are presented and some recommendations are made. (WHK)
The Research Evaluation Committee, which consisted of 14 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Nuclear Safety Research in accordance with the Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the R and D accomplishments achieved for five years from Fiscal Year 1995 to Fiscal Year 1999 at Department of Reactor Safety Research, Department of Fuel Cycle Safety Research, Department of Environmental Safety Research and Department of Safety Research Technical Support in Tokai Research Establishment at JAERI. The Ad Hoc Review Committee consisted of 11 specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from December 2000 to February 2001. The evaluation was performed on the basis of the materials submitted in advance and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on December 11, 2000, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on March 16, 2001. This report describes the result of the evaluation by the Ad Hoc Review Committee on Nuclear Safety Research. (author)
The Research Evaluation Committee, which consisted of 13 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Advanced Science Research in accordance with the Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the accomplishments of the research completed in Fiscal Year 2000 and the adequacy of the programs of the research to be started in Fiscal Year 2002 at Advanced Science Research Center of JAERI. The Ad Hoc Review Committee consisted of eight specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from May to July 2001. The evaluation was performed on the basis of the materials submitted in advance and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on June 26, 2001, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on July 12, 2001. This report describes the result of the evaluation by the Ad Hoc Review Committee on Advanced Science Research. (author)
In 2014 the Executive Officer of the American Physical Society (APS), Kate Kirby, created an Ad-Hoc Committee on LGBT Issues (C-LGBT) charged with reporting on the obstacles to inclusion of LGBT physicists, a term which for the purpose of this report refers to persons who self-identify as lesbian, gay, bisexual, transgender, queer, questioning, intersex, or asexual, as well as other sexual and gender minorities. The full charge was as follows: ``The committee will advise the APS on the current status of LGBT issues in physics, provide recommendations for greater inclusion, and engage physicists in laying the foundation for a more inclusive physics community? More specifically, the committee will investigate LGBT representation in physics, assess the educational and professional climate in physics, recommend changes in policies and practices that impact LGBT physicists, and address other issues that affect inclusion.'' We will present the findings and recommendations of the C-LGBT final report, and a panel discussion will be held following the presentation to discuss the future of APS efforts toward LGBT inclusion in physics.
The Research Evaluation Committee, which consisted of 14 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on High-Temperature Engineering and Research in accordance with the 'Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the R and D accomplishments achieved for five years from Fiscal Year 1995 to Fiscal Year 1999 at Department of HTTR Project and Department of Advanced Nuclear Heat Technology in Oarai Research Establishment of JAERI. The Ad Hoc Review Committee consisted of nine specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from December 2000 to February 2001. The evaluation was performed on the basis of the materials submitted in advanced and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on December 8, 2000, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on March 16, 2001. This report describes the result of the evaluation by the Ad Hoc Review Committee on High-Temperature Engineering and Research. (author)
The Research Evaluation Committee, which consisted of 13 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Advanced Photon and Synchrotron Radiation Research in accordance with the 'Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the adequacy of the R and D programs to be implemented for five years starting in Fiscal Year 2002 at Advanced Photon Research Center and at Synchrotron Radiation Research Center in Kansai Research Establishment of JAERI. The Ad Hoc Review Committee consisted of ten specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from May to July 2001. The evaluation was performed on the basis of the materials submitted in advanced and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on June 21, 2001, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on July 12, 2001. This report describes the result of the evaluation by the Ad Hoc Review Committee on Advanced Photon and Synchrotron Radiation Research. (author)
The Research Evaluation Committee, which consisted of 13 members from outside of the Japan Atomic Energy Research Institute (JAERI), set up an Ad Hoc Review Committee on Materials Science Research in accordance with the Fundamental Guideline for the Evaluation of Research and Development (R and D) at JAERI' and its subsidiary regulations in order to evaluate the adequacy of the R and D programs to be implemented for five years starting in Fiscal Year 2003 at Department of Materials Science in Tokai Research Establishment of JAERI. The Ad Hoc Review Committee consisted of eight specialists from outside of JAERI. The Ad Hoc Review Committee conducted its activities from April 2002 to August 2002. The evaluation was performed on the basis of the materials submitted in advance and of the oral presentations made at the Ad Hoc Review Committee meeting which was held on June 5th, 2002, in line with the items, viewpoints, and criteria for the evaluation specified by the Research Evaluation Committee. The result of the evaluation by the Ad Hoc Review Committee was submitted to the Research Evaluation Committee, and was judged to be appropriate at its meeting held on August 5th, 2002. This report describes the result of the evaluation by the Ad Hoc Review Committee on Materials Science Research. (author)
Motivated by the exciting new application paradigm of using amalgamated technologies of the Internet and wireless, the next generation communication networks (also called 'ubiquitous', 'complex' and 'unstructured' networking) are changing the way we develop and apply our future systems and services at home and on local, national and global scales. Whatever the interconnection - a WiMAX enabled networked mobile vehicle, MEMS or nanotechnology enabled distributed sensor systems, Vehicular Ad hoc Networking (VANET) or Mobile Ad hoc Networking (MANET) - all can be classified under new networking s
Full Text Available We study the energy-efficient configuration of multihop paths with automatic repeat request (ARQ mechanism in wireless ad hoc networks. We adopt a cross-layer design approach and take both the quality of each radio hop and the battery capacity of each transmitting node into consideration. Under certain constraints on the maximum tolerable transmission delay and the required packet delivery ratio, we solve optimization problems to jointly schedule the transmitting power of each transmitting node and the retransmission limit over each hop. Numerical results demonstrate that the path configuration methods can either significantly reduce the average energy consumption per packet delivery or considerably extend the average lifetime of the multihop route.
National Assessment Governing Board, 2006
The task of the Ad Hoc Committee on Planning for the the National Assessment of Educational Progress (NAEP) 12th Grade Assessments in 2009 addresses three policy areas: (1) Conducting assessment at the state level in 12th grade; (2) Reporting on 12th grade student preparedness for college-credit coursework, training for employment and entrance…
R. Kaptein; M. Koolen; J. Kamps
In this paper we explore the use of category information for ad hoc retrieval in Wikipedia. We show that techniques for entity ranking exploiting this category information can also be applied to ad hoc topics and lead to significant improvements. Automatically assigned target categories are good sur
An evidence-based unified definition of lifelong and acquired premature ejaculation : report of the second International Society for Sexual Medicine Ad Hoc Committee for the Definition of Premature Ejaculation
Serefoglu, Ege Can; McMahon, Chris G; Waldinger, Marcel D; Althof, Stanley E; Shindel, Alan; Adaikan, Ganesh; Becher, Edgardo F; Dean, John; Giuliano, Francois; Hellstrom, Wayne J G; Giraldi, Annamaria; Glina, Sidney; Incrocci, Luca; Jannini, Emmanuele; McCabe, Marita; Parish, Sharon; Rowland, David; Segraves, R Taylor; Sharlip, Ira; Torres, Luiz Otavio
INTRODUCTION: The International Society for Sexual Medicine (ISSM) Ad Hoc Committee for the Definition of Premature Ejaculation developed the first evidence-based definition for lifelong premature ejaculation (PE) in 2007 and concluded that there were insufficient published objective data at that ti
An evidence-based unified definition of lifelong and acquired premature ejaculation : report of the second international society for sexual medicine ad hoc committee for the definition of premature ejaculation
Serefoglu, Ege Can; McMahon, Chris G; Waldinger, Marcel D; Althof, Stanley E; Shindel, Alan; Adaikan, Ganesh; Becher, Edgardo F; Dean, John; Giuliano, Francois; Hellstrom, Wayne Jg; Giraldi, Annamaria; Glina, Sidney; Incrocci, Luca; Jannini, Emmanuele; McCabe, Marita; Parish, Sharon; Rowland, David; Segraves, R Taylor; Sharlip, Ira; Torres, Luiz Otavio
INTRODUCTION: The International Society for Sexual Medicine (ISSM) Ad Hoc Committee for the Definition of Premature Ejaculation developed the first evidence-based definition for lifelong premature ejaculation (PE) in 2007 and concluded that there were insufficient published objective data at that ti
Biswas, Kamanashis; Ali, Md. Liakat
Mobile Ad Hoc Network (MANET) is a collection of communication devices or nodes that wish to communicate without any fixed infrastructure and pre-determined organization of available links. The nodes in MANET themselves are responsible for dynamically discovering other nodes to communicate. Although the ongoing trend is to adopt ad hoc networks for commercial uses due to their certain unique properties, the main challenge is the vulnerability to security attacks. A number of challenges like o...
Narayanan, Sathya; Byun, YoungJoon; Cebrowski Institute; CSUMB, C.S.I.T. Program
In conjunction with the NPS C.S. Department MWC Group, this research looks at establishing an Ad Hoc Peer-to-Peer network on cell phones, specifically using the Android OS. Work comprised of Android Device, Library, and Application Design. The Library used was AODV (Ad Hoc on demand Distance Vector) and hardware devices must be controlled directly in addition to application enhancements. A prototype has been created and communication was achieved. Future work to include enhancements to contro...
Rabel, Matthias Reinhard
A new in-vehicle network is developed and elaborated. The new protocol hierarchy aims at an ad hoc integration of typical in-vehicle networks, like CAN, IEEE 1394 and others. Therefore several communication protocols are developed. First an overall communication scheme needs to be available to allow end-to-end communication. This is done similar to OSI Layer 5, as session based communication. Sessions allow transitive communication paths without interruption. With this, an ad hoc behavior of ...
Full Text Available A vehicular Ad-hoc network is composed of moving cars as nodes without any infrastructure. Nodes self-organize to form a network over radio links. Security issues are commonly observed in vehicular ad hoc networks; like authentication and authorization issues. Secure Clustering plays a significant role in VANETs. In recent years, various secure clustering techniques with distinguishing feature have been newly proposed. In order to provide a comprehensive understanding of these techniques are designed for VANETs and pave the way for the further research, a survey of the secure clustering techniques is discussed in detail in this paper. Qualitatively, as a result of highlighting various techniques of secure clustering certain conclusions are drawn which will enhance the availability and security of vehicular ad hoc networks. Nodes present in the clusters will work more efficiently and the message passing within the nodes will also get more authenticated from the cluster heads.
Aldabbas, Hamza; Janicke, Helge; Al-Bayatti, Ali; 10.5121/ijwmn.2012.4117
Mobile ad hoc networks (MANETs) are self-configuring infrastructure-less networks comprised of mobile nodes that communicate over wireless links without any central control on a peer-to-peer basis. These individual nodes act as routers to forward both their own data and also their neighbours' data by sending and receiving packets to and from other nodes in the network. The relatively easy configuration and the quick deployment make ad hoc networks suitable the emergency situations (such as human or natural disasters) and for military units in enemy territory. Securing data dissemination between these nodes in such networks, however, is a very challenging task. Exposing such information to anyone else other than the intended nodes could cause a privacy and confidentiality breach, particularly in military scenarios. In this paper we present a novel framework to enhance the privacy and data confidentiality in mobile ad hoc networks by attaching the originator policies to the messages as they are sent between nod...
Unlike any other book in this area, this book provides innovative solutions to security issues, making this book a must read for anyone working with or studying security measures. Vehicular Ad Hoc Network Security and Privacy mainly focuses on security and privacy issues related to vehicular communication systems. It begins with a comprehensive introduction to vehicular ad hoc network and its unique security threats and privacy concerns and then illustrates how to address those challenges in highly dynamic and large size wireless network environments from multiple perspectives. This book is richly illustrated with detailed designs and results for approaching security and privacy threats.
Benslama, Malek; Batatia, Hadj
Random SALOHA and CSMA protocols that are used to access MAC in ad hoc networks are very small compared to the multiple and spontaneous use of the transmission channel. So they have low immunity to the problems of packet collisions. Indeed, the transmission time is the critical factor in the operation of such networks. The simulations demonstrate the positive impact of erasure codes on the throughput of the transmission in ad hoc networks. However, the network still suffers from the intermittency and volatility of its efficiency throughout its operation, and it switches quickly to the satura
An Evidence-Based Unified Definition of Lifelong and Acquired Premature Ejaculation: Report of the Second International Society for Sexual Medicine Ad Hoc Committee for the Definition of Premature Ejaculation
Serefoglu, Ege Can; McMahon, Chris G.; Waldinger, Marcel D.; Stanley E. Althof; Shindel, Alan; Adaikan, Ganesh; Becher, Edgardo F; Dean, John; Giuliano, Francois; Hellstrom, Wayne JG; Giraldi, Annamaria; Glina, Sidney; Incrocci, Luca; Jannini, Emmanuele; McCabe, Marita
INTRODUCTION: The International Society for Sexual Medicine (ISSM) Ad Hoc Committee for the Definition of Premature Ejaculation developed the first evidence-based definition for lifelong premature ejaculation (PE) in 2007 and concluded that there were insufficient published objective data at that time to develop a definition for acquired PE. AIM: The aim of this article is to review and critique the current literature and develop a contemporary, evidence-based definition for acquired PE and/o...
Oxygen-18 is a stable isotope that is used as a tracer for several biomedical applications. The two primary applications are the study of organismal energy expenditure and organ specific utilization of glucose. The former uses 18O along with deuterium to measure carbon dioxide production of free-living animals and humans. Total energy expenditure is calculated from carbon dioxide production using the standard equations of indirect calorimetry. The later uses 18O as a precursor for the production of 18F, a radionuclide that is incorporated into glucose homologues and injected into the circulating blood. When the glucose homologues are taken up by an organ (usually brain), the organ can be imaged using positron emission tomography (PET). Both of these techniques have become major research and, in the case of PET, diagnostic tools during the last decade. This growth in the use of these tools has increased the world-wide demand for 18O in the form of water. In 1998, this demand could not be met by suppliers and significant delivery delays have been encountered by many investigators and clinicians. Some suppliers are quoting delivery delays of a year. These delays have disrupted on-going research and delayed the start of new projects. The shortage has resulted in a price increase of nearly 50% in 18O water. The disruption of 18O supply in 1998 is the second such disruption in the past decade. Commercial suppliers could not provide sufficient product in late 1990 following the forced closure of the US government production facility at Los Alamos Laboratory. Delivery delays lasted throughout 1991. In August of 1998, the council of the North American Association for the Study of Obesity formed an ad hoc committee to gather information regarding the supply and demand for 18O and to investigate potential solutions to the problem
Full Text Available Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns and detailed local radio interactions. This study examines these factors alone and in combination, using simulation and analysis from first principles. Our results include both specific constants and general relationship Scaling helpful in understanding the limitations of wireless ad hoc networks. We examine interactions of the 802.11 MAC and ad hoc forwarding and the effect on capacity for several simple configurations and traffic patterns. While 802.11 discovers reasonably good schedules, we nonetheless observe capacities markedly less than optimal for very simple chain and lattice networks with very regular traffic patterns. We validate some simulation results with experiments. We also show that the traffic pattern determines whether an ad hoc network’s per node capacity will scale to large networks. In particular, we show that for total capacity to scale up with network size the average distance between source and destination nodes must remain small as the network grows. Nonlocal traffic patterns in which this average distance grows with the network size result in a rapid decrease of per node capacity.
Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Berket, Karlo [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment.
Modern HENP experiments such as CMS and Atlas involve as many as 2000 collaborators around the world. Collaborations this large will be unable to meet often enough to support working closely together. Many of the tools currently available for collaboration focus on heavy-weight applications such as videoconferencing tools. While these are important, there is a more basic need for tools that support connecting physicists to work together on an ad hoc or continuous basis. Tools that support the day-to-day connectivity and underlying needs of a group of collaborators are important for providing light-weight, non-intrusive, and flexible ways to work collaboratively. Some example tools include messaging, file-sharing, and shared plot viewers. An important component of the environment is a scalable underlying communication framework. In this paper we will describe our current progress on building a dynamic and ad hoc collaboration environment and our vision for its evolution into a HENP collaboration environment
Caballero-Gil, P; Molina-Gil, J; Hernández-Goya, C
A Vehicular Ad-Hoc Network (VANET) is a form of Mobile ad-hoc network, to provide communications among nearby vehicles and between vehicles and nearby fixed roadside equipment. The key operation in VANETs is the broadcast of messages. Consequently, the vehicles need to make sure that the information has been sent by an authentic node in the network. VANETs present unique challenges such as high node mobility, real-time constraints, scalability, gradual deployment and privacy. No existent technique addresses all these requirements. In particular, both inter-vehicle and vehicle-to-roadside wireless communications present different characteristics that should be taken into account when defining node authentication services. That is exactly what is done in this paper, where the features of inter-vehicle and vehicle-to-roadside communications are analyzed to propose differentiated services for node authentication, according to privacy and efficiency needs.
M. Kamalakannan; V. Khanaa
Early simulation experience with wireless ad hoc networks suggests that their capacity can be surprisingly low, due to the requirement that nodes forward each others’ packets. The achievable capacity depends on network size, traffic patterns and detailed local radio interactions. This study examines these factors alone and in combination, using simulation and analysis from first principles. Our results include both specific constants and general relationship Scaling helpful in understanding t...
Vey, Quentin; Pirovano, Alain; Radzik, José; Garcia, Fabien
Aeronautical communication systems are constantly evolving in order to handle the always increasing flow of data generated by civil aviation. In this article we first present communication systems currently used for en-route aircraft. We then propose Aeronautical Ad hoc NETwork (AANET) as a complementary communication system and demonstrate its connectivity and assess the throughput by simulations based on real aircraft trajectories over the French sky and over the Atlantic ocean.
Pervaiz, Mohammad O.; Cardei, Mihaela; Wu, Jie
Wireless networks provide rapid, untethered access to information and computing, eliminating the barriers of distance, time, and location for many applications ranging from collaborative, distributed mobile computing to disaster recovery (such as fire, flood, earthquake), law enforcement (crowd control, search, and rescue), and military communications (command, control, surveillance, and reconnaissance). An ad hoc network is a collection of wireless mobile hosts forming a temporary network without the aid of any established infrastructure or centralized administration [11
Full Text Available Mobile ad hoc networks (MANETs are self-configuring infrastructure-less networks comprised of mobile nodes that communicate over wireless links without any central control on a peer-to-peer basis.These individual nodes act as routers to forward both their own data and also their neighbours’ data by sending and receiving packets to and from other nodes in the network. The relatively easy configuration and the quick deployment make ad hoc networks suitable the emergency situations (such as human or natural disasters and for military units in enemy territory. Securing data dissemination between these nodes in such networks, however, is a very challenging task. Exposing such information to anyone else other than the intended nodes could cause a privacy and confidentiality breach, particularly in military scenarios. In this paper we present a novel framework to enhance the privacy and data confidentiality in mobile ad hoc networks by attaching the originator policies to the messages as they are sent between nodes. We evaluate our framework using the Network Simulator (NS-2 to check whether the privacy and confidentiality of the originator are met. For this we implemented the Policy Enforcement Points (PEPs, as NS-2 agents that manage and enforce the policies attached to packets at every node in the MANET.
Hearings before the Ad Hoc Committee on Maritime Education and Training of the Committee on Merchant Marine and Fisheries, Ninety-Third Congress; Second Session on Officer Requirements, and Session on Maritime Education Regarding Safety at Sea. Serial No. 93-44.
Congress of the U.S., Washington, DC. House Committee on Merchant Marine and Fisheries.
The publication consists of Congressional hearings before the Ad Hoc Committee on Maritime Education and Training: (1) June 26, 1974 hearing pertaining to officer requirements and (2) November 19, 1974 hearing on maritime education regarding safety at sea. Estimated cost per graduate for the U. S. Merchant Marine 1973 class was $31,100. Supply and…
Full Text Available In this article we present a survey of secure ad hoc routing protocols for wireless networks. Ad hoc network is a collection of nodes that is connected through a wireless medium forming rapidly changing topologies. Attacks on ad hoc network routing protocols disrupt network performance and reliability with there solution. We briefly present the most popular protocols that follow the table-driven and the source-initiated on-demand approaches. The comparison between the proposed solutions and parameters of ad hoc network shows the performance according to secure protocols. We discuss in this paper routing protocol and challenges and also discuss authentication in ad hoc network.
Full Text Available Most of the existing routing protocols for ad hoc networks are designed to scale in networks of a few hundred nodes. They rely on state concerning all links of the network or links on the route between a source and a destination. This may result in poor scaling properties in larger mobile networks or when node mobility is high. Using location information to guide the routing process is one of the most often proposed means to achieve scalability in large mobile networks. However, location-based routing is difficult when there are holes in the network topology. We propose a novel position-based routing protocol called Proximity Aware Routing for Ad-hoc networks (PARA to address these issues. PARA selects the next hop of a packet based on 2-hops neighborhood information. We introduce the concept of proximity discovery. The knowledge of a nodes 2-hops neighborhood enables the protocol to anticipate concave nodes and helps reduce the risks that the routing protocol will reach a concave node in the network. Our simulation results show that PARAs performance is better in sparse networks with little congestion. Moreover, PARA significantly outperforms GPSR for delivery ratio, transmission delay and path length. Our results also indicate that PARA delivers more packets than AODV under the same conditions.
We consider an ad hoc network which uses multihop routing and slotted ALOHA for its MAC contention. We show that the minimum time required for a packet to reach the destination from the origin scales linearly with the distance. We define this delay as the minimum time required for a causal path to form between the source and destination. We derive the distributional properties of the connection time using ideas from first passage percolation and epidemic processes. We show that the delay scales linearly with the distance and also provide asymptotic results (with respect to time) for the positions of the nodes which are able to receive information from a transmitter located at the origin. We also provide simulation results to support the theoretical results.
A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet
A dramatic increase in the number of computing devices with wireless communication capability has resulted in the emergence of a new class of computer worms which specifically target such devices. The most striking feature of these worms is that they do not require Internet connectivity for their propagation but can spread directly from device to device using a short-range radio communication technology, such as WiFi or Bluetooth. In this paper, we develop a new model for epidemic spreading of these worms and investigate their spreading in wireless ad hoc networks via extensive Monte Carlo simulations. Our studies show that the threshold behaviour and dynamics of worm epidemics in these networks are greatly affected by a combination of spatial and temporal correlations which characterize these networks, and are significantly different from the previously studied epidemics in the Internet.
Sarkar, Subir Kumar
The military, the research community, emergency services, and industrial environments all rely on ad hoc mobile wireless networks because of their simple infrastructure and minimal central administration. Now in its second edition, Ad Hoc Mobile Wireless Networks: Principles, Protocols, and Applications explains the concepts, mechanism, design, and performance of these highly valued systems. Following an overview of wireless network fundamentals, the book explores MAC layer, routing, multicast, and transport layer protocols for ad hoc mobile wireless networks. Next, it examines quality of serv
Ali Bazghandi; Mehdi Bazghandi
The purpose of this paper is investigating behaviors of Ad Hoc protocols in Agent-based simulation environments. First we bring brief introduction about agents and Ad Hoc networks. We introduce some agent-based simulation tools like NS-2. Then we focus on two protocols, which are Ad Hoc On-demand Multipath Distance Vector (AODV) and Destination Sequenced Distance Vector (DSDV). At the end, we bring simulation results and discuss about their reasons.
A wireless ad hoc network consists of a number of mobile nodes that temporarily form a dynamic infrastructure-less network. New routing protocols that can adapt to the frequent topology changes induced by node mobility and varying link qualities are needed. During the last decade dozens of different ad hoc routing protocols have been proposed, optimized and partially compared, mainly through simulation studies. This thesis takes an experimental approach to the evaluation of ad hoc routing pro...
Sujatha J; Mr. Manoj Challa
In ad hoc networking the polices are vulnerable to a wide range of security in network attacks.The design of enforcing and revoking policy mechanisms is a challenging task, especially in comparison tosecuring the ad hoc network. In this paper, the designed and implemented mechanism to provide a trustedcommunication for file sharing in ad-hoc network is explained, where the mechanism has been developedwith the help of polices where each policy is a combination of set of parameters. Simulation ...
Sarkar, Subir Kumar; Puttamadappa, C
Ad hoc mobile wireless networks have seen increased adaptation in a variety of disciplines because they can be deployed with simple infrastructures and virtually no central administration. In particular, the development of ad hoc wireless and sensor networks provides tremendous opportunities in areas including disaster recovery, defense, health care, and industrial environments. Ad Hoc Mobile Wireless Networks: Principles, Protocols and Applications explains the concepts, mechanisms, design, and performance of these systems. It presents in-depth explanations of the latest wireless technologies
Füßler, Holger; Mauve, Martin; Hartenstein, Hannes; Käsemann, Michael; Vollmer, Dieter
On this paper we investigate the use of ad-hoc routing algorithms for the exchange of data between vehicles. There are two main aspects that are of interest in this context: the specific characteristics of ad-hoc networks formed by vehicles and the applicability of existing ad-hoc routing schemes to networks that display these characteristics. In order to address both aspects we generate realistic vehicular movement patterns of highway traffic scenarios using a well validated traffic simulati...
Marwa Altayeb; Imad Mahgoub
In recent years, the aspect of vehicular ad hoc network (VANET) is becoming an interesting research area; VANET is a mobile ad hoc network considered as a special case of mobile ad hoc network (MANET). Similar to MANET, VANET is characterized as autonomous and self-configured wireless network. However, VANET has very dynamic topology, large and variable network size, and constrained mobility; these characteristics led to the need for efficient routing and resource saving VANET protocols, to f...
Vaishali D. Khairnar; Pradhan, S. N.
One of the emerging applications that belong to ambient systems is to transparently and directly interconnect vehicles on roads, making an ad hoc network that enables a variety of applications through distributed software without the need of any fixed and dedicated infrastructure. The network as well as the embedded computers and sensors in the vehicle will be invisible to the driver, who will get the required services during his journey. New type of ad hoc network is the Vehicular Ad hoc Net...
Mohammed, Mohammed Khalid Hassan
The continual changing of self-organizing nodes located in an infrastructure-less mesh network is called ad hoc network. The recent years have witnessed a rapid growth of interest in ad hoc networking. This research with the aid of Java Native Interface (JNI) and UNIX kernel tools for network, a method to build a Mobile Ad hoc Network (MANET) has been implemented for Android devices to provide supplementary way of communication in certain situations where network infrastructure does not exist...
The paper considers, the different multicasting routing protocols in wireless mobile Ad hoc network (MANET).An Ad hoc network is composed of mobile nodes without the presence of a wired support infrastructure .In this environment routing/multicasting protocols are faced with the challenge of producing multihop router under host mobility and band constraints. Various approaches and routing protocol have been proposed to address Ad hoc networking problems and multiple standardization effort wit...
Presenting cutting-edge research, Intrusion Detection in Wireless Ad-Hoc Networks explores the security aspects of the basic categories of wireless ad-hoc networks and related application areas. Focusing on intrusion detection systems (IDSs), it explains how to establish security solutions for the range of wireless networks, including mobile ad-hoc networks, hybrid wireless networks, and sensor networks.This edited volume reviews and analyzes state-of-the-art IDSs for various wireless ad-hoc networks. It includes case studies on honesty-based intrusion detection systems, cluster oriented-based
A novel mechanism was specified by which a node in ad hoc network may autoconfigure an IP address which is unique throughout the mobile ad hoc network. This new algorithm imposes less and constant overhead and delay in obtaining an IP address, and fully utilizes the available addresses space of an ad hoc network, and independent of the existing routing protocol, and less prone to security threats. Moreover, a new Join/Leave mechanism was proposed as an enhancement to the new IP address autoconfiguration algorithm, to support the overall operation of the existing routing protocol of wireless ad hoc networks.
Al-Nahari, Abdulaziz; Mohamad, Mohd Murtadha
Decreasing the route rediscovery time process in reactive routing protocols is challenging in mobile ad hoc networks. Links between nodes are continuously established and broken because of the characteristics of the network. Finding multiple routes to increase the reliability is also important but requires a fast update, especially in high traffic load and high mobility where paths can be broken as well. The sender node keeps re-establishing path discovery to find new paths, which makes for long time delay. In this paper we propose an improved multipath routing protocol, called Receiver-based ad hoc on demand multipath routing protocol (RB-AOMDV), which takes advantage of the reliability of the state of the art ad hoc on demand multipath distance vector (AOMDV) protocol with less re-established discovery time. The receiver node assumes the role of discovering paths when finding data packets that have not been received after a period of time. Simulation results show the delay and delivery ratio performances are improved compared with AOMDV. PMID:27258013
Full Text Available Indonesia is one of developing countries with high land traffic density. This traffic density could cause traffic jam, traffic accidents and other disturbances. This research had developed a simulator that could calculate the traffic density of roads in urban areas. With the use of this simulator, the researcher could calculate the time needed if the source node transports the message to the destination node by using the ad hoc network communication facility. In this research, every vehicle utilizes multi-hop communication in a communication network. The vehicle sends the message through flooding message and passes on the received message to other vehicles. Based on the simulation done on map size 10 km x 10 km with a total of 20 vehicles on the road, it was calculated that the simulator could transmit the message to its destination on the 106th second from node 3 and with the total of 200 vehicles on the road, the simulator could transmit the message to its destination on the 22nd second from node 5.
An Evidence-Based Unified Definition of Lifelong and Acquired Premature Ejaculation: Report of the Second International Society for Sexual Medicine Ad Hoc Committee for the Definition of Premature Ejaculation
Ege Can Serefoglu, MD
Conclusion: The ISSM unified definition of lifelong and acquired PE represents the first evidence-based definition for these conditions. This definition will enable researchers to design methodologically rigorous studies to improve our understanding of acquired PE. Serefoglu EC, McMahon CG, Waldinger MD, Althof SE, Shindel A, Adaikan G, Becher EF, Dean J, Giuliano F, Hellstrom WJG, Giraldi A, Glina S, Incrocci L, Jannini E, McCabe M, Parish S, Rowland D, Segraves RT, Sharlip I, and Torres LO. An evidence-based unified definition of lifelong and acquired premature ejaculation: Report of the second International Society for Sexual Medicine Ad Hoc Committee for the Definition of Premature Ejaculation. Sex Med 2014;2:41–59.
Friederich, Simon; Harlander, Robert; Karaca, Koray
We examine physicists' charge of ad hocness against the Higgs mechanism in the standard model of elementary particle physics. We argue that even though this charge never rested on a clear-cut and well-entrenched definition of "ad hoc", it is based on conceptual and methodological assumptions and pri
Full Text Available Ad hoc teamwork refers to the challenge of designing agents that can influence the behavior of a team, without prior coordination with its teammates. This paper considers influencing a flock of simple robotic agents to adopt a desired behavior within the context of ad hoc teamwork. Specifically, we examine how the ad hoc agents should behave in order to orient a flock towards a target heading as quickly as possible when given knowledge of, but no direct control over, the behavior of the flock. We introduce three algorithms which the ad hoc agents can use to influence the flock, and we examine the relative importance of coordinating the ad hoc agents versus planning farther ahead when given fixed computational resources. We present detailed experimental results for each of these algorithms, concluding that in this setting, inter-agent coordination and deeper lookahead planning are no more beneficial than short-term lookahead planning.
Demin Li; Jie Zhou; Jingjuan Zhu; Jiacun Wang
Ad hoc social networks are special social networks, such as ad hoc tactical social networks, ad hoc firefighter social networks, and ad hoc vehicular social networks. The social networks possess both the properties of ad hoc network and social network. One of the challenge problems in ad hoc social networks is opinion impact and consensus, and the opinion impact plays a key role for information fusion and decision support in ad hoc social networks. In this paper, consider the impact of physic...
This SpringerBrief investigates the special challenges of broadcast design in cognitive radio (CR) ad hoc networks. It introduces two broadcast protocols in CR ad hoc networks: a quality-of-service based broadcast protocol under blind information and a fully-distributed broadcast protocol with collision avoidance. A novel unified analytical model is also presented to analyze the performance of the broadcast protocols. This is the first book dedicated to the unique broadcast design challenges in CR ad hoc networks. The authors also discuss the recent research on the performance analysis of broa
Katie Genter; Peter Stone
Ad hoc teamwork refers to the challenge of designing agents that can influence the behavior of a team, without prior coordination with its teammates. This paper considers influencing a flock of simple robotic agents to adopt a desired behavior within the context of ad hoc teamwork. Specifically, we examine how the ad hoc agents should behave in order to orient a flock towards a target heading as quickly as possible when given knowledge of, but no direct control over, the behavior of the flock...
Mona Holsve Ofigsbø
Full Text Available The article proposes a simple, scalable and robust scheme for the distribution of revocation information in mobile ad hoc networks (MANETs. The scheme is intended for ad hoc networks with a planned origin, and where a common point of trust exists. Mobile ad hoc networks have limited available bandwidth. The revocation lists must therefore be specific to the network. They are established with the aid of trusted gateways reporting the identity of the nodes to a central trusted entity. To minimize overhead, the revocation lists are distributed along with the routing messages. In the articles we discuss how the scheme can be implemented in conjunction with the predominant routing protocols in ad hoc networks. The article also provides a detailed security analysis of the proposed protocols, partly based on the use of formal methods.
Goldsby, Michael E.; Johnson, Michael M.; Kilman, Dominique Marie (Sandia National Laboratories, Albuquerque, NM); Bierbaum, Neal Robert; Chen, Helen Y.; Ammerlahn, Heidi R.; Tsang, Rose P.; Nicol, David M. (University of Illinois, Urbana, IL)
This report describes the results of research targeting improvements in the robustness of message transport in wireless ad hoc networks. The first section of the report provides an analysis of throughput and latency in the wireless medium access control (MAC) layer and relates the analysis to the commonly used 802.11 protocol. The second section describes enhancements made to several existing models of wireless MAC and ad hoc routing protocols; the models were used in support of the work described in the following section. The third section of the report presents a lightweight transport layer protocol that is superior to TCP for use in wireless networks. In addition, it introduces techniques that improve the performance of any ad hoc source routing protocol. The fourth section presents a novel, highly scalable ad hoc routing protocol that is based on geographic principles but requires no localization hardware.
Sun Baolin; Li Layuan
In wireless ad hoc network environments, every link is wireless and every node is mobile. Those features make data lost easily as well as multicasting inefficient and unreliable. Moreover, Efficient and reliable multicast in wireless ad hoc network is a difficult issue. It is a major challenge to transmission delays and packet losses due to link changes of a multicast tree at the provision of high delivery ratio for each packet transmission in wireless ad hoc network environment.In this paper, we propose and evaluate Reliable Adaptive Multicast Protocol (RAMP) based on a relay node concept. Relay nodes are placed along the multicast tree. Data recovery is done between relay nodes. RAMP supports a reliable multicasting suitable for mobile ad hoc network by reducing the number of packet retransmissions. We compare RAMP with SRM (Scalable Reliable Multicast). Simulation results show that the RAMP has high delivery ratio and low end-to-end delay for packet transmission.
Full Text Available Ad hoc networks are acollection of mobile nodes communicating via wireless channels without any fixedinfrastructure. Because of their ease and low cost of building, ad hoc networks have a lot of attractiveapplications in different fields. The topology of ad hoc networks changes dynamically, and each node in thenetwork can act as a host or router.With the increase in the number of wirelessdevices andlarge amountof traffic to be exchanged, the demand for scalable routing protocols has increased. This paper presents ascalable routing protocol, based on AODV protocol, called the Extended Clustering Ad Hoc RoutingProtocol (ECRP. This is a hybrid protocol, which combines reactive and proactive approaches in routing.The protocol uses theGlobal PositioningSystem todetermine the position of certain nodesin the network.The evaluation methodology and simulation results obtained showthat the protocol is efficient and scaleswell in large networks
KERNÁCS János; SZILÁGYI Szabolcs
An ad hoc network is a self-organizingnetwork of wireless links connecting mobile nodes.The mobile nodes can communicate without aninfrastructure. They form an arbitrary topology, wherethe nodes play the role of routers and are free to moverandomly. Mobile ad hoc networks requireanonymous communications, in order to thwart newwireless passive attacks, and to protect new assets ofinformation such as nodes’ locations, motion patterns,network topology and traffic patterns in addition toconventio...
Mamun, Mohammad Saiful Islam; Miyaji, Atsuko
This paper1 presents an efficient approach to an existing batch verification system on Identity based group signature (IBGS) which can be applied to any Mobile ad hoc network device including Vehicle Ad hoc Networks (VANET). We propose an optimized way to batch signatures in order to get maximum throughput from a device in runtime environment. In addition, we minimize the number of pairing computations in batch verification proposed by B. Qin et al. for large scale VANET. We introduce a batch...
Nguyen, Son Thanh
Wireless and ad hoc communication systems create additional challenges for the implementation of security and reliability services when compared to fxed networks. On the one hand, the inherent characteristics of wireless environment contribute serious system vulnerabilities if the security requirements are not met. On the other hand, the mobility pattern as well as resource constraints of ad hoc devices make security design more di cult. The principal objective of SWACOM pro...
Shahrukh Khalid; Athar Mahboob; Choudhry Fahad Azim; Aqeel Ur Rehman
Ad hoc networks lack support of infrastructure and operate in a shared bandwidth wireless environment. Presently, such networks have been realized by various adaptations in Internet Protocol (IP) architecture which was developed for infrastructure oriented hierarchical networks. The IP architecture has its known problem and issues even in infrastructure settings, like IP address overloading, mobility, multihoming, and so forth. Therefore, when such architecture is implemented in ad hoc scenar...
Dong, Yao; Sadegh Aminian, Mohammad
Terrestrial free-space optical (FSO) communication uses visible or infrared wavelengths to broadcast high speed data wirelessly through the atmospheric channel. The performance of terrestrial FSO channel mainly depends on the local atmospheric conditions. Ad hoc networks offer cost-effective solutions for communications in areas where infrastructure is unavailable, e.g., intelligent transport system, disaster recovery and battlefield scenarios. Traditional ad hoc networks operate in the radio...
Boite, Julien; Leguay, Jérémie
International audience Cellular wireless technologies (e.g. LTE) can be used to build cellular ad hoc networks. In this new class of ad hoc networks, nodes are equipped with two radio interfaces: one being a terminal, the other one being an access point. In this context, attachment decisions based on traditional criteria (e.g. signal quality) may lead to network partitions or suboptimal path lengths, thus making access point selection critical to ensure efficient network connectivity. This...
Arjun Singh; Surbhi Chauhan; Kamal Kant; Reshma Doknaia
Secure and efficient communication among a set of mobile nodes is one of the most important aspects in ad-hoc wireless networks. Wireless networks are particularly vulnerable to intrusion, as they operate in open medium, and use cooperative strategies for network communications. By efficiently merging audit data from multiple network sensors, we analyze the entire ad hoc wireless network for intrusions and try to inhibit intrusion attempts. This paper presents an intrusion detection system fo...
In this work, we address the question of how to enable a system to operate despite the presence of misbehavior. Specifically, in a mobile ad-hoc network, how can we keep the network functional for normal nodes when other nodes do not route and forward correctly? Node misbehavior due to selfish or malicious reasons or faulty nodes can significantly degrade the performance of mobile ad-hoc networks. Existing approaches such as economic incentives or secure routing by cryptographic means allevi...
A, Renuka; Shet, K. C.
Mobile Ad-hoc Network (MANET) is a collection of autonomous nodes or terminals which communicate with each other by forming a multi-hop radio network and maintaining connectivity in a decentralized manner. The conventional security solutions to provide key management through accessing trusted authorities or centralized servers are infeasible for this new environment since mobile ad hoc networks are characterized by the absence of any infrastructure, frequent mobility, and wireless links. We p...
ZHANG Rui-shan; CHEN Ke-fei
A proactive threshold signature scheme is very important to tolerate mobile attack in mobile ad hoc networks. In this paper, we propose an efficient proactive threshold RSA signature scheme for ad hoc networks. The scheme consists of three protocols: the initial secret share distribution protocol, the signature generation protocol and the secret share refreshing protocol. Our scheme has three advantages. First, the signature generation protocol is efficient. Second, the signature generation protocol is resilient. Third, the share refreshing protocol is efficient.
de Graaf,, Dirk C; Berg, van den, C.A.; Boucherie, Richard J.; Brouwer, Frank; Bruin, de, K.; Elfrink, Herman; Fernandez-Diaz, Irene; Heemstra de Groot, Sonia; Haan, de, R.J.; Jongh, de, J.; Nunez, Sindo; Ommeren, van, F.J.; Roijers, Frank; Stemerdink, Jan; Tromp, Erik
Wireless ad-hoc networks will enable emergency services to continuously overview and act upon the actual status of the situation by retrieving and exchanging detailed up-to-date information between the rescue workers. Deployment of high-bandwidth, robust, self-organising ad-hoc networks will enable quicker response to typical what/where/when questions, than the more vulnerable low-bandwidth communication networks currently in use. This paper addresses a number of results of the Easy Wireless ...
Ramin Karimi; Norafida Ithnin; Shukor Abd Razak; Sara Najafzadeh
Vehicular Ad Hoc Networks are highly mobile wireless ad hoc networks. Routing of data in VANETs is a challenging task due to rapidly changing topology and high speed mobility of vehicles. Geographic routing protocols are becoming popular due to advancement and availability of GPS devices. In this paper, we review the existing non DTN Geographic Routing Protocols for VANETs and also provide a qualitative comparison of them.
Security has becomes a primary concern in order to provide protected communication between mobile nodes in a host environment .Unlike the wire line network, the unique characteristics mobile ad-hoc networkpose a collection on autonomous nodes of terminals. Which ommunication with each other by forming multihost radio network and maintaining connectivity in a decentralized manner. Node in Ad-hoc network path is dynamic network topology. These challenges clearly make a case for building multif...
Fugen stopped operating for 25 years on March 29, 2003. The report reviews the results of development of technologies of practical use of plutonium and the operation control and international cooperation. The evaluation terms are the objects, meaning, project, working system and results of researches and developments and others. Fugen had been operated safely for long time to prove the various kinds of technical performances. The basic technologies for demonstration reactor were not used, because its construction project was discontinued. However, a large fruits of storage of nuclear fuel cycle technologies, promoting nuclear industry technologies and influence of operation control technologies to LWR were obtained. It includes abstracts, construction of committee for FBR and fuel cycle (13 members), discussion, the evaluation method, evaluation results and reference. (S.Y.)
I. M. B. Nogales
Full Text Available Bluetooth is a cutting-edge technology used for implementing wireless ad hoc networks. In order to provide an overall scheme for mobile ad hoc networks, this paper deals with scatternet topology formation and routing algorithm to form larger ad hoc wireless Networks. Scatternet topology starts by forming a robust network, which is less susceptible to the problems posed by node mobility. Mobile topology relies on the presence of free nodes that create multiple connections with the network and on their subsequently rejoining the network. Our routing protocol is a proactive routing protocol, which is tailor made for the Bluetooth ad hoc network. The connection establishment connects nodes in a structure that simplifies packet routing and scheduling. The design allows nodes to arrive and leave arbitrarily, incrementally building the topology and healing partitions when they occur. We present simulation results that show that the algorithm presents low formation latency and also generates an efficient topology for forwarding packets along ad-hoc wireless networks.
LIN Wei; YANG Yong-Tian
A routing algorithm called DNH for increasing efficiency of mobile ad hoc network is presented, which is based on a new criterion called TSS ( Temporarily Steady State) , combining with wireless transmission theory that makes networks topology correspondingly stabilization. Also the DNH algorithm has the characteristics of giving up queuing in a node, but selecting another idle node instead of the node for forwarding data packets if the node has a full throughput. Simulation evaluation shows that selecting another node is better than queuing in a full throughout node if some conditions are satisfied, especially during a sea battle, every warship in ad hoc network wants to contest time and increase propagation reliability. The DNH algorithm can help decrease routing time, and raise efficiency of marine ad hoc networks.
Full Text Available Vehicular ad-hoc networks (VANETs are a promising communication scenario. Several new applications are envisioned, which will improve traffic management and safety. In comparison to other communication networks, Vehicular Ad-hoc Networks (VANETs have unique requirements with respect to applications, types of communication, self-organization and other issues. VANETspecific protocol layers, a staircase approach for interaction among layers and the use of an information connector for cross-layer information exchange using the publisher/subscriber pattern. The main goal of VANET is providing safety and comfort for passengers. Each vehicle equipped with VANET device will be a node in the Ad-hoc network and can receive
Mobile Ad-hoc Network (MANET) is a collection of autonomous nodes or terminals which communicate with each other by forming a multi-hop radio network and maintaining connectivity in a decentralized manner. The conventional security solutions to provide key management through accessing trusted authorities or centralized servers are infeasible for this new environment since mobile ad hoc networks are characterized by the absence of any infrastructure, frequent mobility, and wireless links. We propose a hierarchical group key management scheme that is hierarchical and fully distributed with no central authority and uses a simple rekeying procedure which is suitable for large and high mobility mobile ad hoc networks. The rekeying procedure requires only one round in our scheme and Chinese Remainder Theorem Diffie Hellman Group Diffie Hellmann and Burmester and Desmedt it is a constant 3 whereas in other schemes such as Distributed Logical Key Hierarchy and Distributed One Way Function Trees, it depends on the num...
Käsemann, Michael; Füßler, Holger; Hartenstein, Hannes; Mauve, Martin
We present and analyze a reactive location service RLS for mobile ad hoc networks. RLS provides a mobile node in a wireless ad-hoc network with the means to inquire the current geographical position of another node on-demand and can be used as a building block for location-based routing. We provide a comparison of RLS to an ideal omniscient location service as well as to the complex Grid Location Service (GLS). In addition, we compare the performance of greedy location-based routing in combin...
Vehicular ad hoc network (VANET) is an application of mobile ad hoc technology in transportation systems, it has become an important part of ITS. Since multi-hop link is hard to set up in sparse VANET, a traffic-aware routing (TAR) protocol is proposed which estimates vehicle average neighbors (VAN) of roads by exchanging beacon messages between encounter vehicles. Road with high VAN is preferred to be selected as part of forwarding path at intersection. Packets are forwarded to the next intersection in road in a greedy manner. Simulations show that TAR outperforms the compared protocols in terms of both packet delivery ratio and average end-to-end delay.
PRADIP M. JAWANDHIYA,
Full Text Available Security is an essential requirement in mobile ad hoc network (MANETs. Compared to wired networks, MANETs are more vulnerable to security attacks due to the lack of a trusted centralized authority and limited resources. Attacks on ad hoc networks can be classified as passive and active attacks, depending on whether the normal operation of the network is disrupted or not. In this paper, we are describing the all prominent attacks described in literature in a consistent manner to provide a concise comparison on attack types. To the best of our knowledge, this is the first paper that studies all the existing attacks on MANETs.
Full Text Available A spontaneously mannered decentralized network with no formal infrastructure and limited in temporal and spatial extent where each node communicate with each other over a wireless channel and is willing to forward data for other nodes is called as Wireless Ad Hoc network. In this research study, we proposed a routing strategy based on gossip based routing approach that follows the proactive routing with some treatment for wireless Ad Hoc network. The analytical verification of our proposed idea shows that it is a better approach based on gossip routing.
JIN Zhao-hui; WANG Shun-man; XU Kai; LIANG Qing
A new dynamic encryption application in ad-hoc networks is proposed. The advantages of this method are its being able to use the previous ciphertext as a seed of a new encryption process, rendering the encryption process effective in all communication process by continuous dynamic key generation together with synchronization, and its capability to cut back on system bandages to a greater extent, which is valuable for the ad-hoc circumstance. In addition, the rationality and effectiveness of this novel encryption method have been verified by the test results.
Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility o
Er. Rakesh Kumar,
Full Text Available hoc networks are self configuring network and by a random and quickly changing network topology; thus the need for a robust dynamic routing protocol can accommodate such an environment. Different protocols govern the mobile ad hoc networks and to improve the packet delivery ratio of Destination-Sequenced Distance Vector (DSDV routing protocol in mobile ad hoc networks with high mobility, a message exchange scheme for its invalid route reconstruction is being used. Three protocols AODV, DSDV and I-DSDV were simulated using NS-2 package and were compared in terms of packet delivery ratio, end to end delay routing overhead in different environment; varying number of nodes, speed and pause time. Simulation results show that IDSDVcompared with DSDV, it reduces the number of dropped data packets with little increased overhead at higher rates of node mobility but still compete with AODV in higher node speed and number of node.
Full Text Available Merging MPLS into multicast routing protocol in Mobile Ad hoc network is an elegant method to enhance the network performance and an efficient solution for multicast scalability and control overhead problems. Based on the Wireless MPLS technology, the mechanism and evaluation of a new multicast protocol, the Label Switching Multicast Routing Protocol (LSMRP is presented in this paper.
Al Hanbali, Ahmad; Altman, Eitan; Nain, Philippe
The Transmission Control Protocol (TCP) was designed to provide reliable end-to-end delivery of data over unreliable networks. In practice, most TCP deployments have been carefully designed in the context of wired networks. Ignoring the properties of wireless ad hoc networks can lead to TCP implemen
Khanpara, Pimal; Valiveti, Sharada; Kotecha, K.
The ad hoc networks have dynamic topology and are infrastructure less. So it is required to implement a new network protocol for providing efficient end to end communication based on TCP/IP structure. There is a need to re-define or modify the functions of each layer of TCP/IP model to provide end to end communication between nodes. The mobility of the nodes and the limited resources are the main reason for this change. The main challenge in ad hoc networks is routing. Due to the mobility of the nodes in the ad hoc networks, routing becomes very difficult. Ant based algorithms are suitable for routing in ad hoc networks due to its dynamic nature and adaptive behavior. There are number of routing algorithms based on the concept of ant colony optimizations. It is quite difficult to determine the best ant based algorithm for routing as these algorithms perform differently under various circumstances such as the traffic distribution and network topology. In this paper, the overview of such routing algorithms is given.
Location is fundamental information in Vehicular Ad-hoc Networks (VANETs). Almost all VANET applications rely on location information. Therefore it is of importance to ensure location information integrity, meaning that location information is original (from the generator), correct (not bogus or fabricated) and unmodified (value not changed). We…
Kock, B.A.; Schmidt, J.R.
This paper describes a concept combining mobile IP and ad hoc routing to create a robust mobile network. In this network all nodes are mobile and globally and locally reachable under the same IP address. Essential for implementing this network are the dynamic mobile IP routers. They act as gateways
Full Text Available In this paper, we describe a secure cluster-routing protocol based on a multilayer scheme in ad hoc networks. This work provides scalable, threshold authentication scheme in ad hoc networks. We present detailed security threats against ad hoc routing protocols, specifically examining cluster-based routing. Our proposed protocol, called "authentication based on multilayer clustering for ad hoc networks" (AMCAN, designs an end-to-end authentication protocol that relies on mutual trust between nodes in other clusters. The AMCAN strategy takes advantage of a multilayer architecture that is designed for an authentication protocol in a cluster head (CH using a new concept of control cluster head (CCH scheme. We propose an authentication protocol that uses certificates containing an asymmetric key and a multilayer architecture so that the CCH is achieved using the threshold scheme, thereby reducing the computational overhead and successfully defeating all identified attacks. We also use a more extensive area, such as a CCH, using an identification protocol to build a highly secure, highly available authentication service, which forms the core of our security framework.
Fernandez, F. M.; Garcia, J.; Semorádová, Iveta; Znojil, Miloslav
Roč. 54, č. 12 (2015), s. 4187-4203. ISSN 0020-7748 Institutional support: RVO:61389005 Keywords : quantum mechanics * physical Hilbert spaces * ad hoc inner product * singular potentials regularized * low lying energies Subject RIV: BE - Theoretical Physics Impact factor: 1.184, year: 2014
Full Text Available An ad hoc network is a group of wireless mobile hosts that are connected momentarily through wireless connections in the dearth of any centralized control or some supporting services. The mobile ad hoc network is at risk by its environment because of the vulnerabilities at channel and node level. The conventional security mechanisms deals with only protecting resources from unauthorized access, but are not capable to safeguard the network from who offer resources. Adding trust to the on hand security infrastructures would improvise the security of these environments. A trust oriented security framework for adhoc network using ontological engineering approach is proposed by modeling ad hoc network, the OLSR (Optimized Link State Routing protocol and trust model as OWL (Ontology Web language ontologies, which are integrated using Jena. In this model, a trustor can calculate its trust about trustee and use the calculated trust values to make decisions depending on the context of the application or interaction about granting or rejecting it. A number of experiments with a potential implementation of suggested framework are performed to validate the characteristics of a trust oriented model suggested by the literature by this framework
Many emerging applications in mobile adhoc networks involve group-oriented communication. Multicast is an efficient way of supporting group oriented applications, mainly in mobile environment with limited bandwidth and limited power. For using such applications in an adversarial environment as military, it is necessary to provide secure multicast communication. Key management is the fundamental challenge in designing secure multicast communications. In many multicast interactions, new member can join and current members can leave at any time and existing members must communicate securely using multicast key distribution within constrained energy for mobile adhoc networks. This has to overcome the challenging element of "1 affects n" problem which is due to high dynamicity of groups. Thus this paper shows the specific challenges towards multicast key management protocols for securing multicast key distribution in mobile ad hoc networks, and present relevant multicast key management protocols in mobile ad hoc n...
Imran, Muhammad; Qaraqe, Khalid; Alouini, Mohamed-Slim; Vasilakos, Athanasios
This book investigates energy management approaches for energy efficient or energy-centric system design and architecture and presents end-to-end energy management in the recent heterogeneous-type wireless network medium. It also considers energy management in wireless sensor and mesh networks by exploiting energy efficient transmission techniques and protocols. and explores energy management in emerging applications, services and engineering to be facilitated with 5G networks such as WBANs, VANETS and Cognitive networks. A special focus of the book is on the examination of the energy management practices in emerging wireless cellular and ad hoc networks. Considering the broad scope of energy management in wireless cellular and ad hoc networks, this book is organized into six sections covering range of Energy efficient systems and architectures; Energy efficient transmission and techniques; Energy efficient applications and services. .
Full Text Available Wireless Ad-hoc Network is a temporary and decentralized type of wireless network. Due to security vulnerabilities in the routing protocol currently, this type of network is unprotected to network layer attacks. Black-hole attack is such a type of attack and is a Denial-of-Service (DoS attack. Due to its nature, the attack makes the source node send all the data packets to a Black-hole node that ends up dropping all the packets. The aim of this paper is to reflect light on the severe effects of a Black-hole attack in a Wireless Ad-hoc network and the drawbacks of the security mechanisms being used for the mitigation of this attack.
Full Text Available The aim of this work is to model the nodes battery discharge in wireless ad hoc networks. Many work focus on the energy consumption in such networks. Even, the research in the highest layers of the ISO model, takes into account the energy consumption and efficiency. Indeed, thenodes that form such network are mobiles, so no instant recharge of battery. Also with special type of ad hoc networks are wireless sensors networks using non-rechargeable batteries. All nodes with an exhausted battery are considered death and left the network. To consider the energy consumption, in this work we model using a Markov chain, the discharge of the battery considering of instant activation and deactivation distribution function of these nodes.
Full Text Available Optimal multihop routing in ad hoc networks requires the exchange of control messages at the MAC and network layer in order to set up the (centralized optimization problem. Distributed opportunistic space-time collaboration (OST is a valid alternative that avoids this drawback by enabling opportunistic cooperation with the source at the physical layer. In this paper, the performance of OST is investigated. It is shown analytically that opportunistic collaboration outperforms (centralized optimal multihop in case spatial reuse (i.e., the simultaneous transmission of more than one data stream is not allowed by the transmission protocol. Conversely, in case spatial reuse is possible, the relative performance between the two protocols has to be studied case by case in terms of the corresponding capacity regions, given the topology and the physical parameters of network at hand. Simulation results confirm that opportunistic collaborative communication is a promising paradigm for wireless ad hoc networks that deserves further investigation.
Full Text Available Optimal multihop routing in ad hoc networks requires the exchange of control messages at the MAC and network layer in order to set up the (centralized optimization problem. Distributed opportunistic space-time collaboration (OST is a valid alternative that avoids this drawback by enabling opportunistic cooperation with the source at the physical layer. In this paper, the performance of OST is investigated. It is shown analytically that opportunistic collaboration outperforms (centralized optimal multihop in case spatial reuse (i.e., the simultaneous transmission of more than one data stream is not allowed by the transmission protocol. Conversely, in case spatial reuse is possible, the relative performance between the two protocols has to be studied case by case in terms of the corresponding capacity regions, given the topology and the physical parameters of network at hand. Simulation results confirm that opportunistic collaborative communication is a promising paradigm for wireless ad hoc networks that deserves further investigation.
Samara, Ghassan; Al-Salihy, Wafaa A H
Vehicular Ad hoc Networks (VANET) is one of the most challenging research area in the field of Mobile Ad Hoc Networks. In this research we proposed a dynamic power adjustment protocol that will be used for sending the periodical safety message. (Beacon)based on the analysis of the channel status depending on the channel congestion and the power used for transmission. The Beacon Power Control (BPC) protocol first sensed and examined the percentage of the channel congestion, the result obtained was used to adjust the transmission power for the safety message to reach the optimal power. This will lead to decrease the congestion in the channel and achieve good channel performance and beacon dissemination.
杨喜旺; 王华; 焦国太
Mobile Ad Hoc networks has been widely applied to military field, emergency management, public service and so on. Because it is uncertain on network and communication, a great deal of energy will be consumed with nodes increasing and creating routing each other. The reformative on-demand multicast routing protocol was putted forward by researching the energy consuming of multicast routing protocol in Ad Hoc. It will decrease consumption in a big multicast flooding through studying the relaying group net structure based on map or wormhole. The energy consumption is reduced 30% by creating the two kinds of routing principles: minimization of energy consumption and minimization of maximum nodes energy consumption. The simulation result indicates that the reformative RODMRP is effective to reduce the energy consuming while routing protocol built.
Full Text Available Security in sensor networks is one of the most relevant research topics in resource constrained wireless devices and networks. Several attacks can be suffered in ad hoc and wireless sensor networks (WSN, which are highly susceptible to attacks, due to the limited resources of the nodes. In this paper, we propose innovative and lightweight localization techniques that allow for intrusion identification and isolation schemes and provide accurate location information. This information is used by our routing protocol which additionally incorporates a distributed trust model to prevent several routing attacks to the network. We finally evaluate our algorithms for accurate localization and for secure routing which have been implemented and tested in real ad hoc and wireless sensor networks.
Chaqfeh, Moumena; Lakas, Abderrahmane; Lazarova-Molnar, Sanja
Vehicular Ad hoc Networks (VANETs) have become a cornerstone component of Intelligent Transportation Systems (ITS). VANET applications present a huge potential for improving road safety and travel comfort, hence the growing interest of both academia and industry. The main advantage of VANETs is its...... ad hoc nature which does not require fixed infrastructure or centralized administration. However, designing scalable information dissemination techniques for VANET applications remains a challenging task due to the inherent nature of such highly dynamic environments. Existing dissemination techniques...... often resort to simulation for performance evaluation and there are only few studies that offer mathematical modeling. In this paper we provide a comparative study of existing performance modeling approaches for data dissemination techniques designed for different VANET applications. © 2013 IEEE....
Wu, Celimuge; Kumekawa, Kazuya; Kato, Toshihiko
In Vehicular Ad hoc Networks (VANETs), general purpose ad hoc routing protocols such as AODV cannot work efficiently due to the frequent changes in network topology caused by vehicle movement. This paper proposes a VANET routing protocol QLAODV (Q-Learning AODV) which suits unicast applications in high mobility scenarios. QLAODV is a distributed reinforcement learning routing protocol, which uses a Q-Learning algorithm to infer network state information and uses unicast control packets to check the path availability in a real time manner in order to allow Q-Learning to work efficiently in a highly dynamic network environment. QLAODV is favored by its dynamic route change mechanism, which makes it capable of reacting quickly to network topology changes. We present an analysis of the performance of QLAODV by simulation using different mobility models. The simulation results show that QLAODV can efficiently handle unicast applications in VANETs.
Full Text Available In this paper we presents bandwidth estimation scheme for MANET, which uses some components of the two methods for the bandwidth estimation: 'Hello Bandwidth Estimation 'Listen Bandwidth Estimation. This paper also gives the advantages of the proposed method. The proposed method is based on the comparison of these two methods. Bandwidth estimation is an important issue in the Mobile Ad-hoc Network (MANET because bandwidth estimation in MANET is difficult, because each host has imprecise knowledge of the network status and links change dynamically. Therefore, an effective bandwidth estimation scheme for MANET is highly desirable. Ad hoc networks present unique advanced challenges, including the design of protocols for mobility management, effective routing, data transport, security, power management, and quality-of-service (QoS provisioning. Once these problems are solved, the practical use of MANETs will be realizable.
Supriya Kulkarni P
Full Text Available As the necessity of exchanging and sharing data increases, users demand easy connectivity, and fast networks whether they are at work, at home, or on the move. Nowadays, users are interested in interconnecting all their personal electronic devices (PEDs in an ad hoc fashion on the move. This type of network is referred to as Mobile Ad hoc NETwork (MANET. When in such network a smart antenna System (SAS is implemented then we can achieve maximum capacity and improve the quality and coverage. So we are intended to implement such a SAS in the MANET. In this paper we have shown significance of Throughput and Bit Error Rate by implementing SAS in MANET using MATLABR2010a.
Broadcast is an important operation in many network protocols. It is utilized to discover routes to unknown nodes in mobile ad hoc networks (MANETs) and is the key factor in scaling on-demand routing protocols to large networks. This paper presents the Ad Hoc Broadcast Protocol (AHBP) and its performance is discussed. In the protocol, messages are only rebroadcast by broadcast relay gateways that constitute a connected dominating set of the network. AHBP can efficiently reduce the redundant messages which make flooding-like protocols perform badly in large dense networks. Simulations are conducted to determine the performance characteristics of the protocol. The simulation results have shown excellent reduction of broadcast redundancy with AHBP. It also contributes to a reduced level of broadcast collision and congestion.
Nuraj L. Pradhan
We will also focus on an adaptive distributed power management (DISPOW algorithm as an example of the multi-parameter optimization approach which manages the transmit power of nodes in a wireless ad hoc network to preserve network connectivity and cooperatively reduce interference. We will show that the algorithm in a distributed manner builds a unique stable network topology tailored to its surrounding node density and propagation environment over random topologies in a dynamic mobile wireless channel.
K.Seshadri Ramana; A.A. Chari; N.Kasiviswanth
Mobile Ad Hoc Network (MANETs) is a Collection of mobile nodes connected with wireless links.MANET has no fixed topology as the nodes are moving constantly form one place to another place. All the nodes must co-operate with each other in order to route the packets. Cooperating nodes must trust each other. In defining and managing trust in a military MANET, we must consider the interactions between the composite cognitive, social, information and communication networks, and take into account t...
Paoliello Guimaraes, Rafael
Over the last years, Mobile Ad-hoc Networks (MANETs) have captured the attention of the research community. The flexibility and cost savings they provide, due to the fact that no infrastructure is needed to deploy a MANET, is one of the most attractive possibilities of this technology. However, along with the flexibility, lots of problems arise due to the bad quality of transmission media, the scarcity of resources, etc. Since real-time communications will be common in MANETs, there has been ...
Sarvesh Kumar Sharma
Full Text Available In this paper different optimization of Ad-hoc routing algorithm is surveyed and a new method using training based optimization algorithm for reducing the complexity of routing algorithms is suggested. A binary matrix is assigned to each node in the network and gets updated after each data transfer using the protocols. The use of optimization algorithm in routing algorithm can reduce the complexity of routing to the least amount possible.
Komal Zaman; Muddesar Iqbal; Muhammad Shafiq; Azeem Irshad; Saqib Rasool
MANET (Mobile Ad-hoc network) forms a temporary network of wireless mobile nodes without any infrastructure where all nodes are allowed to move freely, configure themselves and interconnect with its neighbors to perform peer to peer communication and transmission. TCP (Transmission Control Protocol) offers reliable, oriented connection and mechanism of end to end delivery. This article provides the review and comparison of existing variants of TCP for instance: The TCP Tahoe, The TCP Reno, Th...
Buchegger, Sonja; Le Boudec, Jean-Yves
Reputation systems in mobile ad-hoc networks can be tricked by the spreading of false reputation ratings, be it false accusations or false praise. Simple solutions such as exclusively relying on one`s own direct observations have drawbacks, as they do not make use of all the information available. We propose a fully distributed reputation system that can cope with false disseminated information. In our approach, everyone maintains a reputation rating and a trust rating about everyone ...
In Ad-hoc-Netzen sind aktive Mitarbeit aller Teilnehmer und Einbringung eigener, knapper Ressourcen zugunsten Anderer unverzichtbar. Das hier vorgestellte verteilte Zugangskontrollsystem schließt dazu unkooperative Nutznießer aus dem Netz aus. Grundlage dafür sind gegenseitige Kooperativitätseinschätzungen der autonomen, einander a priori meist unbekannten Teilnehmer, die durch automatische Verhaltensbeobachtung sowie durch Austausch und Verknüpfung von Einschätzungen ermittelt werden.
Li, Xu; Mitton, Nathalie; Simplot-Ryl, David
Hello protocol is the basic technique for neighborhood discovery in wireless ad hoc networks. It requires nodes to claim their existence/aliveness by periodic `hello' messages. Central to any hello protocol is the determination of `hello' message transmission rate. No fixed optimal rate exists in the presence of node mobility. The rate should in fact adapt to it, high for high mobility and low for low mobility. In this paper, we propose a novel mobility prediction based hello protocol, named ...
Li, Xu; Mitton, Nathalie; Simplot-Ryl, David
International audience Hello protocol is the basic technique for neighborhood discovery in wireless ad hoc networks. It requires nodes to claim their existence/ aliveness by periodic 'hello' messages. Central to a hello protocol is the determination of 'hello' message transmission rate. No fixed optimal rate exists in the presence of node mobility. The rate should in fact adapt to it, high for high mobility and low for low mobility. In this paper, we propose a novel mobility prediction bas...
de Spindler, Alexandre; Grossniklaus, Michael; Lins, Christoph; Norrie, Moira C.
Current mobile phone technologies have fostered the emergence of a new generation of mobile applications. Such applications allow users to interact and share information opportunistically when their mobile devices are in physical proximity or close to fixed installations. It has been shown how mobile applications such as collaborative filtering and location-based services can take advantage of ad-hoc connectivity to use physical proximity as a filter mechanism inherent to the application logi...
Full Text Available A mobile ad-hoc network (MANET is a self-configuring network of mobile routers (and associated hosts connected by wireless links—the union of which form an arbitrary topology. The routers are free to move randomly and organize themselves arbitrarily; thus, the network's wireless topology may change rapidly and unpredictably. MANETs are usually set up in situations of emergency for temporaryoperations or simply if there are no resources to set up elaborate networks. These types of networks operate in the absence of any fixed infrastructure, which makes them easy to deploy, at the same time however, due to the absence of any fixed infrastructure, it becomes difficult to make use of the existing routing techniques for network services, and this poses a number of challenges in ensuring the security of the communication, something that is not easily done as many of the demands of network security conflict with thedemands of mobile networks, mainly due to the nature of the mobile devices (e.g. low power consumption, low processing load. Many of the ad hoc routing protocols that address security issues rely on implicit trust relationships to route packets among participating nodes. Besides the general security objectives like authentication,confidentiality, integrity, availability and non-repudiation, the ad hoc routing protocols should also address location confidentiality, cooperation fairness and absence of traffic diversion. In this paper we attempt to analyze threats faced by the ad hoc network environment and provide a classification of the various security mechanisms. We analyzed the respective strengths and vulnerabilities of the existing routing protocols and suggest a broad and comprehensive framework that can provide a tangible solution.
Vu, Cong Hoan; Soneye, Adeyinka
A Mobile Ad hoc Network (MANET) consists of a set of communicating wireless mobile nodes or devices that do not have any form of fixed infrastructure or centralized authority. The security in MANET has become a significant and active topic within the research community. This is because of high demand in sharing streaming video and audio in various applications, one MANET could be setup quickly to facilitate communications in a hostile environment such as battlefield or emergency situation lik...
LI Xin; MIAO Jian-song; SUN Dan-dan; ZHOU Li-gang; DING Wei
A dynamic traffic distribution algorithm based on the minimization product of packet delay and packet energy consumption is proposed. The algorithm is based on packet delay and energy consumption in allocating traffic, which can optimize the network performance. Simulation demonstrated that the algorithm could dynamically adjust to the traffic distribution between paths, which can minimize the product of packet delay and energy consumption in mobile Ad hoc networks.
OLSR is a well-known proactive routing protocol designed for mobile ad hoc networks (MANETs). OLSR adopts a concept of an MPR mechanism where only mobile nodes selected as MPR nodes can retransmit broadcast packets received from other mobile nodes. Although OLSR reduces the number of broadcast packets, MPR nodes consume more energy than other mobile nodes. Since mobile nodes in MANETs are powered by battery with limited energy, energy efficiency is a critical issue in designing a routing prot...
Intrusion detection in wireless ad hoc networks is a challenging task because these networks change their topologies dynamically, lack concentration points where aggregated traffic can be analyzed, utilize infrastructure protocols that are susceptible to manipulation, and rely on noisy, intermittent wireless communications. Security remains a major challenge for these networks due their features of open medium, dynamically changing topologies, reliance on co-operative algorithms, absence of c...
Gufran Ahmad Ansari; Samir A. Elsagheer Mohamed; A. Nasr
Vehicular Ad Hoc Networks (VANET) is a very promising research venue that can offers many useful and critical applications including the safety applications. Most of these applications require that each vehicle knows precisely its current position in real time. GPS is the most common positioning technique for VANET. However, it is not accurate. Moreover, the GPS signals cannot be received in the tunnels, undergrounds, or near tall buildings. Thus, no positioning service can be obtained in the...
Vehicular Ad Hoc Networks (VANET) has mostly gained the attention of today's research efforts, while current solutions to achieve secure VANET, to protect the network from adversary and attacks still not enough, trying to reach a satisfactory level, for the driver and manufacturer to achieve safety of life and infotainment. The need for a robust VANET networks is strongly dependent on their security and privacy features, which will be discussed in this paper. In this paper a various types of ...
Farkas, Gyula; Genge, Bela; Haller, Piroska
We propose a new platform for implementing secure wireless ad hoc networks. Our proposal is based on a modular architecture, with the software stack constructed directly on the Ethernet layer. Within our platform we use a new security protocol that we designed to ensure mutual authentication between nodes and a secure key exchange. The correctness of the proposed security protocol is ensured by Guttman's authentication tests.
Eui-Jik Kim; Sungkwan Youm
This paper presents a selective cooperative transmission scheme (abbreviated SCT) for ad hoc network with directional antennas that leverages the benefits of directional-only antenna approach and cooperative communication. The main feature of SCT is its adaptability to the channel condition in the network. In other words, when the node sends data, SCT determines its transmission strategy on either direct or cooperative transmission via a relay node called a forwarder, depending on the transmi...
In this paper, we show that the use of directional antennas in wireless ad hoc networks can actually increase interference due to limitations of virtual carrier sensing. We derive a simple mathematical expression for interference in both physical and virtual carrier sense networks, which reveals counter-intuitively that receivers in large dense networks with directional antennas can experience larger interference than in omnidirectional networks unless the beamwidth is sufficiently small. Validity of mathematical analysis is confirmed using simulations.
Full Text Available Positioning a node in Vehicular Ad-Hoc networks is one of the most interested research areas in recent years. In many Ad-Hoc networks such as Vehicular Ad-Hoc networks in which the nodes are considered as vehicles, move very fast in streets and highways. So, to have a safe and fast transport system, any vehicle should know where a traffic problem such as a broken vehicle occurs. GPS is one of the equipments which have been widely used for positioning service. Problem statement: Vehicle can use a GPS receiver to determine its position. But, all vehicles have not been equipped with GPS or they cannot receive GPS signals in some places such as inside of a tunnel. In these situations, the vehicle should use a GPS free method to find its location. Approach: In this study, a new method based on transmission range had been suggested. Results: This algorithm had been compared with a similar algorithm ODAM in same situations. The best performance for Optimized Disseminating Alarm Message (ODAM is when 40% of nodes are equipped with GPS. Conclusion: We executed our algorithm on this situation and compared it with ODAM results. At the end of this study, we can see our algorithm in compare to ODAM has better results.
Security issues are always difficult to deal with in mobile ad hoc networks. People seldom studied the costs of those security schemes respectively and for some security methods designed and adopted beforehand, their effects are often investigated one by one. In fact, when facing certain attacks, different methods would respond individually and result in waste of resources.Making use of the cost management idea, we analyze the costs of security measures in mobile ad hoc networks and introduce a security framework based on security mechanisms cost management. Under the framework, the network system's own tasks can be finished in time and the whole network's security costs can be decreased. We discuss the process of security costs computation at each mobile node and in certain nodes groups. To show how to use the proposed security framework in certain applications, we give examples of DoS attacks and costs computation of defense methods. The results showed that more secure environment can be achieved based on the security framework in mobile ad hoc networks.
Li, Xiaolong; Yang, Yeon-Mo
Wireless Sensor Network (WSN) consists of numerous physically distributed autonomous devices used for sensing and monitoring the physical and/or environmental conditions. A WSN uses a gateway that provides wireless connectivity to the wired world as well as distributed networks. There are many open problems related to Ad-Hoc networks and its applications. Looking at the expansion of the cellular infrastructure, Ad-Hoc network may be acting as the basis of the 4th generation wireless technology with the new paradigm of ‘anytime, anywhere communications’. To realize this, the real challenge would be the security, authorization and management issues of the large scale WSNs. This book is an edited volume in the broad area of WSNs. The book covers various chapters like Multi-Channel Wireless Sensor Networks, its Coverage, Connectivity as well as Deployment. It covers comparison of various communication protocols and algorithms such as MANNET, ODMRP and ADMR Protocols for Ad hoc Multicasting, Location Based C...
Riyaz Shaik, P. Prasanna MuraliKrishna, DR. M.V. Subhramanyam
Full Text Available Now a day, one of the most attractive research topics in the area of Intelligent Traffic Control is Inter vehicle communication. In V2V communication or we can also call VANET i.e. Vehicular ad-hoc network; a vehicle can communicate with its neighboring vehicles even in the absence of a central Base Station. The concept of this shortest communication is to send vehicle safety messages one-to-one or one too-many vehicles via wireless connection. Such messages are generally short in length and have very short lifetime in which they have to reach at the target. The Inter-vehicle communication system is an adhoc network with high mobility and changing number of nodes, where mobile nodes animatedly create temporary networks and transferring messages from one node to others by using multiple hops due to restriction of tiny range. The routing in vehicular Ad hoc Networks (VANET has attracted many attentions during the last few years. So in this thesis we are focusing on the routing concept for the VANET i.e. Principles for routing, disintegration of the routing function and obligation. The data delivery through Vehicular Ad-hoc Networks is challenging since it must efficiently handle rapid topology changes and a fragmented network.
In this paper, we study the distributed-duality-based optimization of a multisubchannel ad hoc cognitive radio network (CRN) that coexists with a multicell primary radio network (PRN). For radio resource allocation in multiuser orthogonal frequency-division multiplexing (MU-OFDM) systems, the orthogonal-access-based exclusive subchannel assignment (ESA) technique has been a popular method, but it is suboptimal in ad hoc networks, because nonorthogonal access between multiple secondary-user links by using shared subchannel assignment (SSA) can bring a higher weighted sum rate. We utilize the Lagrangian dual composition tool and design low-complexity near-optimal SSA resource allocation methods, assuming practical discrete-rate modulation and that the CRN-to-PRN interference constraint has to strictly be satisfied. However, available SSA methods for CRNs are either suboptimal or involve high complexity and suffer from slow convergence. To address this problem, we design fast-convergence SSA duality schemes and introduce several novel methods to increase the speed of convergence and to satisfy various system constraints with low complexity. For practical implementation in ad hoc CRNs, we design distributed-duality schemes that involve only a small number of CRN local information exchanges for dual update. The effects of many system parameters are presented through simulation results, which show that the near-optimal SSA duality scheme can perform significantly better than the suboptimal ESA duality and SSA-iterative waterfilling schemes and that the performance loss of the distributed schemes is small, compared with their centralized counterparts. © 2012 IEEE.
Full Text Available We develop a timed calculus for Mobile Ad Hoc Networks embodying the peculiarities of local broadcast, node mobility and communication interference. We present a Reduction Semantics and a Labelled Transition Semantics and prove the equivalence between them. We then apply our calculus to model and study some MAC-layer protocols with special emphasis on node mobility and communication interference. A main purpose of the semantics is to describe the various forms of interference while nodes change their locations in the network. Such interference only occurs when a node is simultaneously reached by more than one ongoing transmission over the same channel.
The project aims to define and develop a metropolitan area, self-organizing and totally wireless network that we call Mobile Metropolitan Ad-hoc Network (MobileMAN). In a MobileMAN the users device are the network, no infrastructure is strictly required. A MobileMAN is finalized at providing, at a low cost and where and when is needed, the communication and interaction platform for people inside a man. It will support a kind of citizens network by which people could avoid the operators infras...
JI Xiao-jun; TIAN Chang; ZHANG Yu-sen
Wormhole attack is a serious threat against MANET (mobile ad hoc network) and its routing protocols.A new approach-tunnel key node identification (TKNI) was proposed. Based on tunnel-key-node identification and priority-based route discovery, TKNI can rapidly rebuild the communications that have been blocked by wormhole attack. Compared to previous approaches, the proposed approach aims at both static and dynamic topology environment, involves addressing visible and invisible wormhole attack modes, requires no extra hardware, has a low overhead, and can be easily applied to MANET.
Full Text Available In this study, we have proposed a multipath routing protocol for Mobile Ad Hoc Networks. Multipath routing overcomes various problems that occur in data delivery through a single path. The proposed protocol selects multiple neighbor nodes of source node to establish multiple paths towards destination. These nodes are selected based on their minimum remaining distance from destination. We have computed the length of various paths and average hops count for different node density in the network. We have considered only three paths for our evaluation. The results show that path-2 gives better results in term of hop count and path length among three paths.
In large scale model based development, analysis level models are more like knowledge bases than engineering artifacts. Their effectiveness depends, to a large degree, on the ability of domain experts to retrieve information from them ad hoc. For large scale models, however, existing query facili...... applied to several visual modeling languages, implemented, and validated in small case studies, and several controlled experiments....... facilities are inadequate. The Visual Model Query Language (VMQL) is a novel approach that uses the respective modeling language of the source model as the query language, too. The semantics of VMQL is defined formally based on graphs, so that query execution can be defined as graph matching. VMQL has been...
Sarkar, Subir Kumar
Due to significant advantages, including convenience, efficiency and cost-effectiveness, the implementation and use of wireless ad hoc and sensor networks have gained steep growth in recent years. This timely book presents the current state-of-the-art in these popular technologies, providing you with expert guidance for your projects in the field. You find broad-ranging coverage of important concepts and methods, definitions of key terminology, and a look at the direction of future research. Supported with nearly 150 illustrations, the book discusses a variety of critical topics, from topology
Full Text Available The use of standardized and optimized protocols has been recently advocated for different arthropod taxa instead of ad-hoc sampling or sampling with protocols defined on a case-by-case basis. We present a comparison of both sampling approaches applied for spiders in a natural area of Portugal. Tests were made to their efficiency, over-collection of common species, singletons proportions, species abundance distributions, average specimen size, average taxonomic distinctness and behavior of richness estimators. The standardized protocol revealed three main advantages: (1 higher efficiency; (2 more reliable estimations of true richness; and (3 meaningful comparisons between undersampled areas.
Los sistemas de redes ad hoc vehiculares (VANET) tienen como objetivo proporcionar una plataforma para diversas aplicaciones que pueden mejorar la seguridad vial, la eficiencia del tráfico, la asistencia a la conducción, la regulación del transporte, etc. o que pueden proveer de una mejor información y entretenimiento a los usuarios de los vehículos. Actualmente se está llevando a cabo un gran esfuerzo industrial y de investigación para desarrollar un mercado que se estima alcance en un futur...
With the advancement of wireless technology, vehicular ad hoc networks (VANETs) are emerging as a promising approach to realizing 'smart cities' and addressing many important transportation problems such as road safety, efficiency, and convenience.This brief provides an introduction to the large trace data set collected from thousands of taxis and buses in Shanghai, the largest metropolis in China. It also presents the challenges, design issues, performance modeling and evaluation of a wide spectrum of VANET research topics, ranging from realistic vehicular mobility models and opportunistic ro
Herrera Joancomartí, Jordi; Rifà Pous, Helena
El despliegue de un esquema de confianza es fundamental para poder desarrollar servicios de seguridad que permitan administrar y operar una red. Sin embargo, las soluciones empleadas en las redes tradicionales no se adaptan a un entorno ad hoc debido a la naturaleza dinámica y sin infraestructura de estas redes. En el presente trabajo se propone un esquema de confianza práctico y eficiente basado en una infraestructura de clave pública distribuida, umbral y jerárquica, que no requiere sincron...
Basagni, Stefano; Giordano, Silvia; Stojmenovic, Ivan
""An excellent book for those who are interested in learning the current status of research and development . . . [and] who want to get a comprehensive overview of the current state-of-the-art.""-E-Streams This book provides up-to-date information on research and development in the rapidly growing area of networks based on the multihop ad hoc networking paradigm. It reviews all classes of networks that have successfully adopted this paradigm, pointing out how they penetrated the mass market and sparked breakthrough research. Covering both physical issues and applica
Although wireless sensor networks (WSNs) have been employed across a wide range of applications, there are very few books that emphasize the algorithm description, performance analysis, and applications of network management techniques in WSNs. Filling this need, Wireless Ad Hoc and Sensor Networks: Management, Performance, and Applications summarizes not only traditional and classical network management techniques, but also state-of-the-art techniques in this area. The articles presented are expository, but scholarly in nature, including the appropriate history background, a review of current
Macha, Mitchell G. (Inventor); Bullock, John T. (Inventor)
A method and apparatus for a communication system technique involving ad hoc selection of at least two audio streams is provided. Each of the at least two audio streams is a packetized version of an audio source. A data connection exists between a server and a client where a transport protocol actively propagates the at least two audio streams from the server to the client. Furthermore, software instructions executable on the client indicate a presence of the at least two audio streams, allow selection of at least one of the at least two audio streams, and direct the selected at least one of the at least two audio streams for audio playback.
Dai Qinyun; Yao Wangsheng; Peng Jianmin; Su Gang
Network capacity is a key characteristic to evaluate the performance of wireless networks. The goal of this paper is to study the capacity of wireless ad hoc relay network. In the model, there is at most ns source nodes transmitting signal simultaneously in the network and the arbitrarily complex network coding is allowed. The upper capacity bound of the network model are derived from the max-flow min-cut theorem and the lower capacity bound are obtained by the rate-distortion function for the Gaussian source. Finally, simulation results show that the upper network capacity will decrease as the number of source nodes is increased.
Puja Kumari Sharma
Full Text Available MANET is a collection of self-configurable mobile nodes. Several routing protocols are proposed for ad hoc network among which DSR and AODV On demand routing protocols are mostly used. Existing Dynamic source routing protocol is not suitable for large network because packet size gets increased according to the number of nodes travelled by route discovery packet. In this paper, extended DSR routing protocol is proposed to eliminate the above limitation of existing DSR. Proposed protocol will be suitable for small and large both types of networks.
Full Text Available Today, mobile computing is one of the important issues in computer and network sciences. Using the processing power of mobile devices purposefully for solving complex issues is one of the research fields for researchers. One of the important issues in the optimization which needs a high processing power for finding the best possible answer is travelling salesman problem. In this paper, by providing a method based on the distributed parallel genetic algorithm on a number of mobile nodes in the Ad Hoc network, it was attempted to increase the speed of finding the best answer for the travelling salesman algorithm.
Muhammad Nawaz Khan
Full Text Available In mobile ad hoc network resource restrictions on bandwidth, processing capabilities, battery life and memory of mobile devices lead tradeoff between security and resources consumption. Due to some unique properties of MANETs, proactive security mechanism like authentication, confidentiality, access control and non-repudiation are hard to put into practice. While some additional security requirements are also needed, like cooperation fairness, location confidentiality, data freshness and absence of traffic diversion. Traditional security mechanism i.e. authentication and encryption, provide a security beach to MANETs. But some reactive security mechanism is required who analyze the routing packets and also check the overall network behavior of MANETs. Here we propose a local-distributed intrusion detection system for ad hoc mobile networks. In the proposed distributed-ID, each mobile node works as a smart agent. Data collect by node locally and it analyze that data for malicious activity. If any abnormal activity discover, it informs the surrounding nodes as well as the base station. It works like a Client-Server model, each node works in collaboration with server, updating its database each time by server using Markov process. The proposed local distributed- IDS shows a balance between false positive and false negative rate. Re-active security mechanism is very useful in finding abnormal activities although proactive security mechanism present there. Distributed local-IDS useful for deep level inspection and is suited with the varying nature of the MANETs.
Piran, Mohammad Jalil; Babu, G Praveen
The rapid increase of vehicular traffic and congestion on the highways began hampering the safe and efficient movement of traffic. Consequently, year by year, we see the ascending rate of car accidents and casualties in most of the countries. Therefore, exploiting the new technologies, e.g. wireless sensor networks, is required as a solution of reduction of these saddening and reprehensible statistics. This has motivated us to propose a novel and comprehensive system to utilize Wireless Sensor Networks for vehicular networks. We coin the vehicular network employing wireless Sensor networks as Vehicular Ad Hoc and Sensor Network, or VASNET in short. The proposed VASNET is particularly for highway traffic .VASNET is a self-organizing Ad Hoc and sensor network comprised of a large number of sensor nodes. In VASNET there are two kinds of sensor nodes, some are embedded on the vehicles-vehicular nodes- and others are deployed in predetermined distances besides the highway road, known as Road Side Sensor nodes (RSS...
Khyati Choure , Sanjay Sharma
Full Text Available In present scenario, in ad-hoc network, the behavior of nodes are not very stable. They do not work properly and satisfactory. They are not cooperative and acting selfishly. They show their selfishness to share their resources like bandwidth to save life of battery, they are not hasitate to block thepackets sent by others for forwarding and transmit their own packets. Due to higher Mobility of the different nodes makes the situation even more complicated. Multiple routing protocols especially for these conditions have been developed during the last few years, to find optimized routes from a source to some destination.But it is still difficult to know the actual shortest path without attackers or bad nodes. Ad-hoc network suffer from the lot of issues i.e. congestion, Throughput, delay, security, network overhead. Packet delivery ratio is the issues of ongoing research. Cause of node failure may be either natural failure of node links or it may be due to act of an attacker or bad node which may degrade performance of network slowly or drastically, which also need to identify or determined. In this paper, we identify the good and bad nodes. A simulation has been performed to achieve better performance of modified AODV. Good result has been obtained in terms of Throughout, Packet Delivery Ratio.
Full Text Available This paper addresses the issue of deafness problem in Mobile Ad Hoc Networks (MANETs using directional antennas. Directional antennas arebeneficial for wireless ad hoc networks consisting of a collection of wireless hosts. A suitable Medium Access Control (MAC protocol must be designed to best utilize directional antennas. Deafness is caused whentwo nodes are in ongoing transmission and a third node (Deaf Node wants to communicate with one of that node. But it get no response because transmission of two nodes are in process. Though directional antennas offer better spatial reuse, but this problem can have a serious impact on network performance. A New DMAC (Directional Medium Access Control protocol uses flags in DNAV (Directional Network Allocation Vector tables to maintain information regarding the transmissionbetween the nodes in the network and their neighbor’s location. Two performance matrices have been used to show the impact of New DMAC algorithm on Deafness problem using simulator. These are RTS Failure Ratio and RTS Retransmission due to timeout
Full Text Available The ad-hoc networks are the temporarily established wireless networks which does not require fixedinfrastructure it is also called as infrastructure less network. Because of some flaws of adhoc networksuch as shared wireless medium and lack of any central coordination makes them more prone to attacksin comparison with the wired network. Among all the attacks wormhole attack is the most severe attack.In this attack an attacker capture the packets at one location in the network and send it two anotherattacker at a distant location through tunnels which is established through different ways like packetencapsulation, using high power transmission or by using direct antennas. This tunnel between twocolluding attackers is virtual and it is called as a wormhole. The wormhole attack is possible even if theattacker has not comprised any hosts, and all communication provides authenticity and confidentiality.By using the various approaches for finding the solution over wormhole attack, the dynamic informationof the packets could still be modified. So in order to give more robust protection in some special scenariolike battlefields, which requires highly secured information, there is need of developing some securedmechanism for wormhole detection and prevention. Taking into consideration this problem the proposedscheme is developed. This paper discusses proposed works on wormhole attack along with its availablecounter measures in ad-hoc wireless network.
Yi Ping; Jiang Xinghao; Wu Yue; Liu Ning
Mobile ad hoc networking(MANET)has become an exciting and important technology in recent years,because of the rapid proliferation of wireless devices.Mobile ad hoc networks is highly vulnerable to attacks due to the open medium,dynamically changing network topology,cooperative algorithms,and lack of centralized monitoring and management point.The traditional way of protecting networks with firewalls and encryption software is no longer sufficient and effective for those features.A distributed intrusion detection approach based on timed automata is given.A cluster-based detection scheme is presented,where periodically a node is elected as the monitor node for a cluster.These monitor nodes can not only make local intrusion detection decisions,but also cooperatively take part in global intrusion detection.And then the timed automata is constructed by the way of manually abstracting the correct behaviours of the node according to the routing protocol of dynamic source routing(DSR).The monitor nodes can verify the behaviour of every nodes by timed automata,and validly detect real-time attacks without signatures of intrusion or trained data.Compared with the architecture where each node is its own IDS agent,the approach is much more efficient while maintaining the same level of effectiveness.Finally,the intrusion detection method is evaluated through simulation experiments.
Full Text Available Many crucial applications of MANETs like the battlefield, conference and disaster recovery defines the needs for group communications either one-to-many or many-to-many form. Multicast plays an important role in bandwidth scarce multihop mobile ad hoc networks comprise of limited battery power mobile nodes. Multicast protocols in MANETs generate many controls overhead for maintenance of multicast routingstructures due to frequent changes of network topology. Bigger multicast tables for the maintenance of network structures resultsin inefficient consumption of bandwidth of wireless links andbattery power of anemic mobile nodes, which in turn, pose thescalability problems as the network size is scaled up. However,many MANET applications demands scalability from time to time. Multicasting for MANETs, therefore, needs to reduce the state maintenance. As a remedy to these shortcomings, this paper roposes an overlay multicast protocol on application layer. In the proposed protocol titled “Scalable Overlay Multicasting in Mobile Ad Hoc Networks (SOM” the network nodes construct overlay hierarchical framework to reduce the protocols states and constrain their distribution within limited scope. Based on zone around each node, it constructs a virtual structure at application layer mapped with the physical topology at network layer, thus formed two levels of hierarchy. The concept of two level hierarchies reduces the protocol state maintenance and hence supports the vertical scalability. Protocol depends on the location information obtained using a distributed location service, which effectively reduces the overhead for route searching and updating the source based multicast tree.
Full Text Available In mobile ad hoc radio networks, mechanisms on how to access the radio channel are extremely important in order to improve network efficiency. In this paper, the load adaptable medium access control for ad hoc networks (LAMAN protocol is described. LAMAN is a novel decentralized multipacket MAC protocol designed following a cross-layer approach. Basically, this protocol is a hybrid CDMA-TDMA-based protocol that aims at throughput maximization in multipacket communication environments by efficiently combining contention and conflict-free protocol components. Such combination of components is used to adapt the nodes' access priority to changes on the traffic load while, at the same time, accounting for the multipacket reception (MPR capability of the receivers. A theoretical analysis of the system is developed presenting closed expressions of network throughput and packet delay. By simulations the validity of our analysis is shown and the performances of a LAMAN-based system and an Aloha-CDMA-based one are compared.
Kumar, Sumit; Mehfuz, Shabana
In mobile ad-hoc network (MANETs) flooding method is used for broadcasting route request (RREQ) packet from one node to another node for route discovery. This is the simplest method of broadcasting of RREQ packets but it often results in broadcast storm problem, originating collisions and congestion of packets in the network. A probabilistic broadcasting is one of the widely used broadcasting scheme for route discovery in MANETs and provides solution for broadcasting storm problem. But it does not consider limited energy of the battery of the nodes. In this paper, a new energy efficient probabilistic broadcasting (EEPB) is proposed in which probability of broadcasting RREQs is calculated with respect to remaining energy of nodes. The analysis of simulation results clearly indicate that an EEPB route discovery scheme in ad-hoc on demand distance vector (AODV) can increase the network lifetime with a decrease in the average power consumption and RREQ packet overhead. It also decreases the number of dropped packets in the network, in comparison to other EEPB schemes like energy constraint gossip (ECG), energy aware gossip (EAG), energy based gossip (EBG) and network lifetime through energy efficient broadcast gossip (NEBG).
Kunal Vikas Patil; M.R. Dhage
The vehicular ad hoc network (VANET) is a superior newtechnology. Vehicular ad hoc network (VANET) is a subclassof MANET that is mobile ad hoc networks. Vehicular ad hocnetwork provides wireless communication among vehicles andvehicles to roadside equipments. The communication betweenvehicles is more important for safety and more probably forentertainment as well. The performance of communicationdepends on how better the routing takes place in the network.Routing of data depends on routing pr...
Full Text Available Mobile nodes are organized randomly without any access point in Mobile Ad hoc Networks (MANETs. Due to the mobility of nodes, the network congestion occurs. So many congestion control mechanisms were proposed to avoid the congestion avoidance or reducing the congestion status. In this research work, we proposed to develop the Effective Congestion Avoidance Scheme (ECAS, which consists of congestion monitoring, effective routing establishment and congestionless based routing. The overall congestion status is measured in congestion monitoring. In routing establishment, we propose the contention metric in the particular channel in terms of, queue length of packet, overall congestion standard, packet loss rate and packet dropping ratio to monitor the congestion status. Based on the congestion standard, the congestionless based routing is established to reduce the packet loss, high overhead, long delay in the network. By extensive simulation, the proposed scheme achieves better throughput, packet delivery ratio, low end-to-end delay and overhead than the existing schemes.
This book is devoted to the encounter and interaction of agents such as robots with other agents and describes how they cooperate with their previously unknown teammates, forming an Ad Hoc team. It presents a new algorithm, PLASTIC, that allows agents to quickly adapt to new teammates by reusing knowledge learned from previous teammates. PLASTIC is instantiated in both a model-based approach, PLASTIC-Model, and a policy-based approach, PLASTIC-Policy. In addition to reusing knowledge learned from previous teammates, PLASTIC also allows users to provide expert-knowledge and can use transfer learning (such as the new TwoStageTransfer algorithm) to quickly create models of new teammates when it has some information about its new teammates. The effectiveness of the algorithm is demonstrated on three domains, ranging from multi-armed bandits to simulated robot soccer games.
Full Text Available Mobile Ad Hoc Network (MANETs is a Collection of mobile nodes connected with wireless links.MANET has no fixed topology as the nodes are moving constantly form one place to another place. All the nodes must co-operate with each other in order to route the packets. Cooperating nodes must trust each other. In defining and managing trust in a military MANET, we must consider the interactions between the composite cognitive, social, information and communication networks, and take into account the severe resource constraints (e.g., computing power, energy, bandwidth, time, and dynamics (e.g., topology changes, mobility, node failure, propagation channel conditions. Therefore trust is important word which affects the performance of MANET. There are several protocols proposed based on the trust. This paper is a survey of trust based protocols and it proposes some new techniques on trust management in MANETs
A network model is proposed to support service differentiation for mobile Ad Hoc networks by combining a fully distributed admission control approach and the DIFS based differentiation mechanism of IEEE802.11. It can provide different kinds of QoS (Quality of Service) for various applications. Admission controllers determine a committed bandwidth based on the reserved bandwidth of flows and the source utilization of networks. Packets are marked when entering into networks by markers according to the committed rate. By the mark in the packet header, intermediate nodes handle the Received packets in different manners to provide applications with the QoS corresponding to the pre-negotiated profile.Extensive simulation experiments showed that the proposed mechanism can provide QoS guarantee to assured service traffic and increase the channel utilization of networks.
A novel scheme is presented to integrate mobile ad hoc networks (MANETs) with the Internet and support mobility across wireless local area networks (WLANs) and MANETs. The mobile nodes, connected as a MANET, employ the optimize d link state routing (OLSR) protocol for routing within the MANET. Mobility management across WLANs and MANETs is achieved through the hierarchical mobile IPv6 (HMIPv6) protocol. The performance is evaluated on a HMIPv6 based test-bed composed of WLANs and MANETs. The efficiency gain obtained from using HMIPv6 in such a hybrid network is investigated. The investigation result shows that the use of HMIPv6 can achieve up to 27% gain on reducing the handoff latency when a mobile roams within a domain. Concerning the reduction of the signaling load on the Internet, the use of HMIPv6 can achieve at least a 54% gain and converges to 69%.
Full Text Available MANET (Mobile Ad-hoc network forms a temporary network of wireless mobile nodes without any infrastructure where all nodes are allowed to move freely, configure themselves and interconnect with its neighbors to perform peer to peer communication and transmission. TCP (Transmission Control Protocol offers reliable, oriented connection and mechanism of end to end delivery. This article provides the review and comparison of existing variants of TCP for instance: The TCP Tahoe, The TCP Reno, The TCP New Reno, The Lite, The Sack, The TCP Vegas, Westwood and The TCP Fack. TCP’s performance depends on the type of its variants due to missing of congestion control or improper activation procedures such as Slow Start, Fast Retransmission, and Congestion Avoidance, Retransmission, Fast Recovery, Selective Acknowledgement mechanism and Congestion Control. This analysis is essential to be aware about a better TCP implementation for a specific scenario and then nominated a suitable one.
Andrews, Jeff; Haenggi, Martin; Berry, Randy; Jafar, Syed; Guo, Dongning; Shakkottai, Sanjay; Heath, Robert; Neely, Michael; Weber, Steven; Yener, Aylin
The subject of this paper is the long-standing open problem of developing a general capacity theory for wireless networks, particularly a theory capable of describing the fundamental performance limits of mobile ad hoc networks (MANETs). A MANET is a peer-to-peer network with no pre-existing infrastructure. MANETs are the most general wireless networks, with single-hop, relay, interference, mesh, and star networks comprising special cases. The lack of a MANET capacity theory has stunted the development and commercialization of many types of wireless networks, including emergency, military, sensor, and community mesh networks. Information theory, which has been vital for links and centralized networks, has not been successfully applied to decentralized wireless networks. Even if this was accomplished, for such a theory to truly characterize the limits of deployed MANETs it must overcome three key roadblocks. First, most current capacity results rely on the allowance of unbounded delay and reliability. Second, ...
Molinaro, Antonella; Scopigno, Riccardo
This book presents vehicular ad-hoc networks (VANETs) from the their onset, gradually going into technical details, providing a clear understanding of both theoretical foundations and more practical investigation. The editors gathered top-ranking authors to provide comprehensiveness and timely content; the invited authors were carefully selected from a list of who’s who in the respective field of interest: there are as many from Academia as from Standardization and Industry sectors from around the world. The covered topics are organized around five Parts starting from an historical overview of vehicular communications and standardization/harmonization activities (Part I), then progressing to the theoretical foundations of VANETs and a description of the day-one standard-compliant solutions (Part II), hence going into details of vehicular networking and security (Part III) and to the tools to study VANETs, from mobility and channel models, to network simulators and field trial methodologies (Part IV), and fi...
Mobile Advertisement is a location-aware dissemination solution built on top of a vehicular ad-hoc network. We envision a network of WiFi access points that dynamically disseminate data to clients running on the car's smart device. The approach can be considered an alternative to the static advertisement billboards and can be useful to business companies wanting to dynamically advertise their products and offers to people driving their car. The clients can subscribe to information based on specific topics. We present design solutions that use access points as emitters for transmitting messages to wireless-enabled devices equipped on vehicles. We also present implementation details for the evaluation of the proposed solution using a simulator designed for VANET application. The results show that the application can be used for transferring a significant amount of data even under difficult conditions, such as when cars are moving at increased speeds, or the congested Wi-Fi network causes significant packet loss...
Hewer, Thomas D
Vehicle-to-vehicle communications can be used effectively for intelligent transport systems (ITS) and location-aware services. The ability to disseminate information in an ad-hoc fashion allows pertinent information to propagate faster through the network. In the realm of ITS, the ability to spread warning information faster and further is of great advantage to the receivers of this information. In this paper we propose and present a message-dissemination procedure that uses vehicular wireless protocols for influencing traffic flow, reducing congestion in road networks. The computational experiments presented in this paper show how an intelligent driver model (IDM) and car-following model can be adapted to 'react' to the reception of information. This model also presents the advantages of coupling together traffic modelling tools and network simulation tools.
In this work, we evaluate local capacity of wireless ad hoc networks with several medium access protocols and identify the most optimal protocol. We define local capacity as the average information rate received by a receiver randomly located in the network. We analyzed grid pattern protocols where simultaneous transmitters are positioned in a regular grid pattern, pure ALOHA protocols where simultaneous transmitters are dispatched according to a uniform Poisson distribution and exclusion protocols where simultaneous transmitters are dispatched according to an exclusion rule such as node coloring and carrier sense protocols. Our analysis allows us to conjecture that local capacity is optimal when simultaneous transmitters are positioned in a grid pattern based on equilateral triangles and our results show that this optimal local capacity is at most double the local capacity of simple ALOHA protocol. Our results also show that node coloring and carrier sense protocols approach the optimal local capacity by an ...
Full Text Available Notice Board is very essential part of any organization. This paper presents the design and implementation of M-Board (Mobile Notice Board for Ad-hoc Network Environment that can be established and made available for an educational or industry environment. The cost-free communication among the mobile phone clients and server takes place with the help of Bluetooth wireless technology. M-Board is particularly developed as an informative application environment to provide the basic information like daily events or timetable to the users. The design is based on the amalgamation of Java ME with other technologies like Java SE, Java EE, PHP and MySQL. The system is designed to provide simple, easy-to-use, cost-free solution in a ubiquitous environment. The system design is easily implemented and extensible allowing the number of clients in Personal Area Network (PAN for information exchange with the hotspot-server.
Mohamed, Samir A Elsagheer; Ansari, Gufran Ahmad
Vehicular Ad Hoc Networks (VANET) is a very promising research venue that can offers many useful and critical applications including the safety applications. Most of these applications require that each vehicle knows precisely its current position in real time. GPS is the most common positioning technique for VANET. However, it is not accurate. Moreover, the GPS signals cannot be received in the tunnels, undergrounds, or near tall buildings. Thus, no positioning service can be obtained in these locations. Even if the Deferential GPS (DGPS) can provide high accuracy, but still no GPS converge in these locations. In this paper, we provide positioning techniques for VANET that can provide accurate positioning service in the areas where GPS signals are hindered by the obstacles. Experimental results show significant improvement in the accuracy. This allows when combined with DGPS the continuity of a precise positioning service that can be used by most of the VANET applications.
Intrusion detection in wireless ad hoc networks is a challenging task because these networks change their topologies dynamically, lack concentration points where aggregated traffic can be analyzed, utilize infrastructure protocols that are susceptible to manipulation, and rely on noisy, intermittent wireless communications. Security remains a major challenge for these networks due their features of open medium, dynamically changing topologies, reliance on co-operative algorithms, absence of centralized monitoring points, and lack of clear lines of defense. In this paper, we present a cooperative, distributed intrusion detection architecture based on clustering of the nodes that addresses the security vulnerabilities of the network and facilitates accurate detection of attacks. The architecture is organized as a dynamic hierarchy in which the intrusion data is acquired by the nodes and is incrementally aggregated, reduced in volume and analyzed as it flows upwards to the cluster-head. The cluster-heads of adja...
Borch, Ole; Madsen, Per Printz; Broberg, Jacob Honor´e; Hede, Søren Thorhauge; Mikkelsen, Simon Bjerg; Pedersen, Jesper Ellgaard; Sørensen, Christian Br¨auner
In many applications multiple robots in Mobile Ad-hoc Networks are required to collaborate in order to solve a task. This paper shows by proof of concept that a Collaboration Layer can be modelled and designed to handle the collaborative communication, which enables robots in small to medium size...... provided to the application running on the robot. The services are generic because they can be used by many different applications, independent of the task to be solved. Likewise, specific services are requested from the underlying Virtual Machine, such as broadcast, multicast, and reliable unicast. A...... prototype of the Collaboration Layer has been developed to run in a simulated environment and tested in an evaluation scenario. In the scenario five robots solve the tasks of vacuum cleaning and entrance guarding, which involves the ability to discover potential co-workers, form groups, shift from one group...
Akay, Hilal; Tugcu, Tuna
Simulations used for evaluating the performance of routing protocols for Vehicular Ad Hoc Networks (VANET) are mostly based on random mobility and fail to consider individual behaviors of the vehicles. Unrealistic assumptions about mobility produce misleading results about the behavior of routing protocols in real deployments. In this paper, a realistic mobility modeling tool, Mobility for Vehicles (MOVE), which considers the basic mobility behaviors of vehicles, is proposed for a more accurate evaluation. The proposed model is tested against the Random Waypoint (RWP) model using AODV and OLSR protocols. The results show that the mobility model significantly affects the number of nodes within the transmission range of a node, the volume of control traffic, and the number of collisions. It is shown that number of intersections, grid size, and node density are important parameters when dealing with VANET performance.
Dong, Lei; Wang, Yongchao
In this paper, a distributed opportunistic channel access strategy in ad hoc network is proposed. We consider the multiple sources contend for the transmission opportunity, the winner source decides to transmit or restart contention based on the current channel condition. Owing to real data assumption at all links, the decision still needs to consider the stability of the queues. We formulate the channel opportunistic scheduling as a constrained optimization problem which maximizes the system average throughput with the constraints that the queues of all links are stable. The proposed optimization model is solved by Lyapunov stability in queueing theory. The successive channel access problem is decoupled into single optimal stopping problem at every frame and solved with Lyapunov algorithm. The threshold for every frame is different, and it is derived based on the instantaneous queue information. Finally, computer simulations are conducted to demonstrate the validity of the proposed strategy.
Wireless devices have scarcity of resources such as storage capacity and processing power. For WANETs, cooperative caching strategies are proposed in this paper to improve efficiency in information exchange in peer-to-peer fashion. The caching strategies such as small sized caches and large sized...... caches depend on the estimation of density of information being flown in the network. In the former strategy content replacement takes place when new information is received while in the latter a decision is made as to whether the information is to be cached and for how long. In either case every node is...... making expected content diversity and improve performance of information sharing in wireless ad hoc network....
Due to the wide use of communicating mobile devices, mobile ad hoc networks (MANETs) have gained in popularity in recent years. In order that the devices communicate properly, many protocols have been proposed working at different levels. Devices in an MANET are not stationary but may keep moving......, thus the network topology may undergo constant changes. Moreover the devices in an MANET are loosely connected not depending on pre-installed infrastructure or central control components, they exchange messages via wireless connections which are less reliable compared to wired connections. Therefore...... issues in MANETs e.g. mobility and unreliable connections. Specially speaking, 1. We first propose a discrete probabilistic process calculus with which we can model in an MANET that the wireless connection is not reliable, and the network topology may undergo changes. We equip each wireless connection...
The aim of this paper is to discuss the development of an automatic, low-cost system that exploits current or near future wireless communications technology to enable continuous tracking of the location of devices in all environments. The development of such a wireless sensor network involves system design, digital signal processing, protocol development, extraction of ranges and localisation. This paper focuses on the user requirements, system architecture and network positioning. The user requirements are presented with a focus on applications in geodesy. A high level strategy for the positioning function is presented based on an ad-hoc geodetic network positioning method including issues of accuracy, quality and reliability of the node positions. Results show that it is possible to achieve a position deviation that is of the size of the ranging error.
Full Text Available Wireless Mobile Ad-hoc network is upcoming next generation technology. The foremost reason to be the popularity of MANET is its infrastructure less nature. MANET is a group of wireless mobile nodes which are connected wirelessly. Nodes may be highly mobile because the beauty of wireless network (like MANET or cellular system lies in mobility. But due to this mobility of nodes, the topology of the node and network changed frequently. This frequent change topology affect to the communication between nodes. If nodes are within the range of each other they can communicate properly but if nodes are not in the range of each other, communication will not be possible smoothly or even ongoing communication may be disrupt or lost. So there is a need to develop and design a mechanism or system that can handle such types of situation and prevent communication failure or frequent link failure. In the present work a novel booster mechanism approach is proposed to overcome such situation or Link failure. In the proposed Approach, the level of the Power at both the Transmitter as well as Receiver is measured in order to maintain communication smooth between the nodes. If one node is moving away from the communicating node then both moving node will measure its receiving power with respect to the distance and if its current power level reaches the threshold level it switched “ON” its Booster and at the same time it send a message to source node which contains received power level of moving node due to this ,that source node also “ON” its Booster and thus both nodes connect together to protect the link failure during that mobility. The Booster Approach is a novel concept in the direction of smooth communication in dynamic or wireless environment in Mobile Ad hoc Network.
Mohammad Jalil Piran
Full Text Available The rapid increase of vehicular traffic and congest ion on the highways began hampering the safe and efficient movement of traffic. Consequently, year b y year, we see the ascending rate of car accidents and casualties in most of the countries. Therefore, exp loiting the new technologies, e.g. wireless sensor networks, is required as a solution of reduction of these sad dening and reprehensible statistics. This has motiv ated us to propose a novel and comprehensive system to utilize Wireless Sensor Networks for vehicular networks. W e coin the vehicular network employing wireless Senso r networks as Vehicular Ad Hoc and Sensor Network, or VASNET in short. The proposed VASNET is particularl y for highway traffic .VASNET is a self-organizing Ad Hoc and sensor network comprised of a large number of sensor nodes. In VASNET there are two kinds of sensor nodes, some are embedded on the vehicles-veh icular nodes- and others are deployed in predetermi ned distances besides the highway road, known as Road S ide Sensor nodes (RSS. The vehicular nodes are use d to sense the velocity of the vehicle for instance. We can have some Base Stations (BS such as Police Tra ffic Station, Firefighting Group and Rescue Team. The ba se stations may be stationary or mobile. VASNET provides capability of wireless communication betwe en vehicular nodes and stationary nodes, to increas e safety and comfort for vehicles on the highway road s. In this paper we explain main fundamentals and challenges of VASNET
Waqar Farooq; Khan, Muazzam A.; Saad Rehman; Nazar Abbas Saqib
Vehicular Ad Hoc Networks (VANETs) are autonomous and self-configurable wireless ad hoc networks and considered as a subset of Mobile Ad Hoc Networks (MANETs). MANET is composed of self-organizing mobile nodes which communicate through a wireless link without any network infrastructure. A VANET uses vehicles as mobile nodes for creating a network within a range of 100 to 1000 meters. VANET is developed for improving road safety and for providing the latest services of intelligent transport sy...
Wierzbicki, Adam; Zwierko, Aneta; Kotulski, Zbigniew
This paper describes a new protocol for authentication in ad-hoc networks. The protocol has been designed to meet specialized requirements of ad-hoc networks, such as lack of direct communication between nodes or requirements for revocable anonymity. At the same time, a ad-hoc authentication protocol must be resistant to spoofing, eavesdropping and playback, and man-in-the-middle attacks. The article analyzes existing authentication methods based on the Public Key Infrastructure, and finds th...
Bo Yang; Ali R. Hurson
Multimedia data are becoming popular in wireless ad hoc environments. However, the traditional content-based retrieval techniques are inefficient in ad hoc networks due to the multiple limitations such as node mobility, computation capability, memory space, network bandwidth, and data heterogeneity. To provide an efficient platform for multimedia retrieval, we propose to cluster ad hoc multimedia databases based on their semantic contents, and construct a virtual hierarchical indexing infrast...
Vasileios Karyotis; Anastasios Kakalis; Symeon Papavassiliou
In this paper, the spreading of malicious software over ad hoe networks, where legitimate nodes are prone to propagate the infections they receive from either an attacker or their already infected neighbors, is analyzed. Considering the Susceptible-Infected-Susceptible (SIS) node infection paradigm we propose a probabilistic model, on the basis of the theory of closed queuing networks, that aims at describing the aggregated behavior of the system when attacked by malicious nodes. Because of its nature, the model is also able to deal more effectively with the stochastic behavior of attackers and the inherent probabilistic nature of the wireless environment. The proposed model is able to describe accurately the asymptotic behavior of malware-propagative large scale ad hoc networking environments. Using the Norton equivalent of the closed queuing network, we obtain analytical results for its steady state behavior, which in turn is used for identifying the critical parameters affecting the operation of the network. Finally, through modeling and simulation, some additional numerical results are obtained with respect to the behavior of the system when multiple attackers are present, and regarding the time-dependent evolution and impact of an attack.
Di Wu; Zhisheng Liu; Yongxin Feng; Guangxing Wang
There are inherent vulnerabilities that are not easily preventable in the mobile Ad-Hoc networks.To build a highly secure wireless Ad-Hoc network,intrusion detection and response techniques need to be deployed;The intrusion detection and cluster-based Ad-Hoc networks has been introduced,then,an architecture for better intrusion detection based on cluster using Data Mining in wireless Ad-Hoc networks has been shown. A statistical anomaly detection approach has been used.The anomaly detection and trace analysis have been done locally in each node and possibly through cooperation with clusterhead detection in the network.
Full Text Available Multi-path routing represents a promising routing method for wireless mobile ad hoc networks. Multipath routing achieves load balancing and is more resilient to route failures. Numerous multipath routing protocols have been proposed for wireless ad hoc networks and the most important among them is Ad hoc On-demand Multipath Distance Vector (AOMDV. By virtual circuit approach, using the property of node disjointness, its performance is evaluated. The simulation in Network Simulator (ns2 shows that it is good in its throughput with packet delivery ratio with less delay. The results conclude that AOMDV performs well than Ad hoc On-demand Distance Vector (AODV in all above said aspects.
In Ad-hoc networks, key establishment protocol is mainly contributory ,Diffie-Hellman based key agree ment protocol. In this paper, Several typical protocols are analysed and evaluated, and then, their suitability is discussed from the point of view of Ad-Hoc networks.
Singh, Santosh Kumar
Spectrum is a scarce commodity, and considering the spectrum scarcity faced by the wireless-based service providers led to high congestion levels. Technical inefficiencies from pooled spectrum (this is nothing but the "common carrier principle" adopted in oil/gas/electricity pipelines/networks.), since all ad hoc networks share a common pool of channels, exhausting the available channels will force ad hoc networks to block the services. Researchers found that cognitive radio (CR) technology m...
Liu, R. (Rui); Lloyd, E. L. (Errol L.); Marathe, M. V. (Madhav V.); Ramanathan, R. (Ram); Ravi, S. S.
Topology control problems are concerned with the assignment of power values to nodes of an ad hoc network so that the power assignment leads to a graph topology satisfying some specified properties. This paper considers such problems under several optimization objectives, including minimizing the maximum power and minimizing the total power. A general approach leading to a polynomial algorithm is presented for minimizing maximum power for a class of graph properties, called monotone properties. The difficulty of generalizing the approach to properties that are not monoione is pointed out. Problems involving the minimization of total power are known to be NP-complete even for simple graph properties. A general approach that leads to an approximation algorithm for minimizing the total power for some monotone properties is presented. Using this approach, a new approximation algorithm for the problem of minimizing the total power for obtaining a 2-node-connected graph is obtained. It is shown that this algorithm provides a constant performance guarantee. Experimental results from an implementation of the approximation algorithm are also presented.
Utsu, Keisuke; Ishii, Hiroshi
This paper discusses the streaming of high rate media such as video or audio information over ad hoc networks in disaster situations or for temporary events when it is difficult to use fixed infrastructure. The conventional simple flooding is not applicable for this application because it generates a large number of redundant rebroadcast and heavy traffic load to the network. To restrain redundant rebroadcast messages, several methods have been proposed. But since those studies do not take into account the actual load condition at each node that will affect network efficiency, they cannot achieve both ensuring the high message reachability and reducing redundant rebroadcast. In this paper, we propose two novel load-aware flooding methods using the MAC transmission queue information at each node to make the decision about whether rebroadcast messages should be sent or not. Through network simulations, we evaluate and show the effectiveness of our proposals. The result shows that our proposals achieve both ensuring high message reachability and restraint of redundant rebroadcast comparing with existing methods.
Recent advances in embedded computing systems have led to the emergence of wireless sensor networks (SNETs), consisting of small, battery-powered motes with limited computation and radio communication capabilities. SNETs permit data gathering and computation to be deeply embedded in the physical environment. Large scale ad hoc sensor networks (ASNET), when deployed among mobile patients, can provide dynamic data query architecture to allow medical specialists to monitor patients at any place via the web or cellular network. In case of an emergency, doctors and/or nurses will be contacted automatically through their handheld personal digital assistants (PDAs) or cellular phones. In specific, the proposed network consists of sensor nodes at the first layer whose responsibility is to measure, collect and communicate, via wired or wireless interface, readings to a microcontroller presenting the second layer of architecture. Deployed microcontrollers process incoming readings and report to a central system via a wireless interface. The implemented network distinguishes between periodic sensor readings and critical or event driven readings where higher priorities is given for the latter. In this paper we implement 3 special cases for tracking and monitoring patients and doctors using SNETs. In addition, the performance of a large scale of our implementation has been tested by means of mathematical analysis. (author)
Wei-Qiang Xu; Tie-Jun Wu
Mobile ad hoc networks (MANETs) are a kind of very complex distributed communication systems with wireless mobile nodes that can be freely and dynamically self-organized into arbitrary and temporary network topologies. MANETs inherit several limitations of wireless networks, meanwhile make new challenges arising from the specificity of MANETs, such as route failures, hidden terminals and exposed terminals. When TCP is applied in a MANET environment, a number of tough problems have to be dealt with. In this paper, a comprehensive survey on this dynamic field is given. Specifically, for the first time all factors impairing TCP performance are identified based on network protocol hierarchy, I.e., lossy wireless channel at the physical layer; excessive contention and unfair access at the MAC layer; frail routing protocol at the network layer, the MAC layer and the network layer related mobile node; unfit congestion window size at the transport layer and the transport layer related asymmetric path. How these factors degrade TCP performance is clearly explained. Then, based on how to alleviate the impact of each of these factors listed above, the existing solutions are collected as comprehensively as possible and classified into a number of categories, and their advantages and limitations are discussed. Based on the limitations of these solutions, a set of open problems for designing more robust solutions is suggested.
Muneer Bani Yassein
Full Text Available Flying Ad-Hoc Networks (FANETs is a group of Unmanned Air Vehicles (UAVs which completed their work without human intervention. There are some problems in this kind of networks: the first one is the communication between (UAVs. Various routing protocols introduced classified into three categories, static, proactive, reactive routing protocols in order to solve this problem. The second problem is the network design, which depends on the network mobility, in which is the process of cooperation and collaboration between the UAV. Mobility model of FANET is introduced in order to solve this problem. In Mobility Model, the path and speed variations of the UAV and represents their position are defined. As of today, Random Way Point Model is utilized as manufactured one for Mobility in the greater part of recreation situations. The Arbitrary Way Point model is not relevant for the UAV in light of the fact that UAV do not alter their course and versatility, speed quickly at one time because of this reason, we consider more practical models, called Semi-Random Circular Movement (SRCM Mobility Model. Also, we consider different portability models, Mission Plan-Based (MPB Mobility Model, Pheromone-Based Model. Moreover, Paparazzi Mobility Model (PPRZM. This paper presented and discussed the main routing protocols and main mobility models used to solve the communication, cooperation, and collaboration in FANET networks.
Full Text Available In Mobile Ad hoc NETworks (MANETs, mobility of nodes, resource constraints and selfish behavior of nodes are important factors which may degrade the performance. Clustering is an effective scheme to improve the performance of MANETs features such as scalability, reliability, and stability. Each cluster member (CM is associated with only one cluster head (CH and can communicate with the CH by single hop communication. Mobility information is used by many existing clustering schemes such as weighted clustering algorithm (WCA Link expiration time prediction scheme and k-hop compound metric based clustering. In scheme 1 the CH election is based on a weighted sum of four different parameters such as node status, neighbor’s distribution, mobility, and remaining energy which brings flexibility but weight factor for each parameter if difficult. In scheme 2 lifetime of a wireless link between a node pair is predicted by GPS location information. In scheme 3 the predicted mobility parameter is combined with the connectivity to create a new compound metric for CH election. Despite various efforts in mobility clustering, not much work has been done specifically for high mobility nodes. Our proposed solution provides secure CH election and incentives to encourage nodes to honestly participating in election process. Mobility strategies are used to handle the various problems caused by node movements such as association losses to current CHs and CH role changes, for extending the connection lifetime and provide more stable clusters. The conducted simulation results shows that the proposed approach outperforms the existing clustering schemes.
Chauhan, Kamal Kumar; 10.5121/ijans.2012.2207
Secure communication between two nodes in a network depends on reliable key management systems that generate and distribute keys between communicating nodes and a secure routing protocol that establishes a route between them. But due to lack of central server and infrastructure in Mobile Ad hoc Networks (MANETs), this is major problem to manage the keys in the network. Dynamically changes in network's topology causes weak trust relationship among the nodes in the network. In MANETs a mobile node operates as not only end terminal but also as an intermediate router. Therefore, a multi-hop scenario occurs for communication in MANETs; where there may be one or more malicious nodes in between source and destination. A routing protocol is said to be secure that detects the detrimental effects of malicious node(s in the path from source to destination). In this paper, we proposed a key management scheme and a secure routing protocol that secures on demand routing protocol such as DSR and AODV. We assume that MANETs ...
Full Text Available In vehicular ad hoc networks (VANETs, a hotspot, such as a parking lot, is an information source and will receive inquiries from many vehicles for seeking any possible free parking space. According to the routing protocols in literature, each of the vehicles needs to flood its route discovery (RD packets to discover a route to the hotspot before sending inquiring packets to the parking lot. As a result, the VANET nearby an urban area or city center may incur the problem of broadcast storm due to so many flooding RD packets during rush hours. To avoid the broadcast storm problem, this paper presents a hotspot-enabled routing-tree based data forwarding method, called the intelligent information dissemination scheme (IID. Our method can let the hotspot automatically decide when to build the routing-tree for proactive information transmissions under the condition that the number of vehicle routing discoveries during a given period exceeds a certain threshold which is calculated through our developed analytical packet delivery model. The routing information will be dynamically maintained by vehicles located at each intersection near the hotspot if the maintaining cost is less than that of allowing vehicles to discover routes themselves. Simulation results show that this method can minimize routing delays for vehicles with lower packets delivery overheads.
Farivar, Masoud; Ashtiani, Farid
In this paper, we focus on two-dimensional connectivity in sparse vehicular ad hoc networks (VANETs). In this respect, we find thresholds for the arrival rates of vehicles at entrances of a block of streets such that the connectivity is guaranteed for any desired probability. To this end, we exploit a mobility model recently proposed for sparse VANETs, based on BCMP open queuing networks and solve the related traffic equations to find the traffic characteristics of each street and use the results to compute the exact probability of connectivity along these streets. Then, we use the results from percolation theory and the proposed fast algorithms for evaluation of bond percolation problem in a random graph corresponding to the block of the streets. We then find sufficiently accurate two dimensional connectivity-related parameters, such as the average number of intersections connected to each other and the size of the largest set of inter-connected intersections. We have also proposed lower bounds for the case ...
Kaiwartya, Omprakash; Kumar, Sushil; Lobiyal, D. K.; Abdullah, Abdul Hanan; Hassan, Ahmed Nazar
Geographic routing is one of the most investigated themes by researchers for reliable and efficient dissemination of information in Vehicular Ad Hoc Networks (VANETs). Recently, different Geographic Distance Routing (GEDIR) protocols have been suggested in the literature. These protocols focus on reducing the forwarding region towards destination to select the Next Hop Vehicles (NHV). Most of these protocols suffer from the problem of elevated one-hop link disconnection, high end-to-end delay and low throughput even at normal vehicle speed in high vehicle density environment. This paper proposes a Geographic Distance Routing protocol based on Segment vehicle, Link quality and Degree of connectivity (SLD-GEDIR). The protocol selects a reliable NHV using the criteria segment vehicles, one-hop link quality and degree of connectivity. The proposed protocol has been simulated in NS-2 and its performance has been compared with the state-of-the-art protocols: P-GEDIR, J-GEDIR and V-GEDIR. The empirical results clearly reveal that SLD-GEDIR has lower link disconnection and end-to-end delay, and higher throughput as compared to the state-of-the-art protocols. It should be noted that the performance of the proposed protocol is preserved irrespective of vehicle density and speed. PMID:25429415
TilotmaYadav; Partha Pratim Bhattacharya
In this paper, system operating margin (SOM) is estimated for vehicular ad-hoc networks in absence and presence of Rayleigh fading. The Ad-hoc IEEE 802.11 model is considered for estimating the signal strength and system operating margin. Rayleigh fading was then simulated and system operating margin are estimated in Rayleigh fading environment for different standard modulation schemes.
Sandberg, Chaleece; Sebastian, Rajani; Kiran, Swathi
Background: The typicality effect is present in neurologically intact populations for natural, ad-hoc, and well-defined categories. Although sparse, there is evidence of typicality effects in persons with chronic stroke aphasia for natural and ad-hoc categories. However, it is unknown exactly what influences the typicality effect in this…
Full Text Available The aim of this study is to analyze and compare performance of both reactive and proactive Mobile Ad hoc Networks (MANETs routing protocols using different environments. Wireless networks are divided into two types: infrastructure and ad hoc network. In wireless ad hoc networks each node can be a sender, router and receiver, so these types of network are less structure compared to infrastructure network. Therefore wireless ad hoc networks need special routing protocols to overcome the limitations of wireless ad hoc networks. Wireless ad hoc networks routing protocols can be categorized into two types: reactive (on demand routing protocols and proactive routing protocols. In proactive routing protocols the nodes periodically send control messages across the network to build routing table. Different routing protocols have been simulated using GloMoSim (Global Mobile Information system simulation library and PARSEC compiler. Five multi-hop wireless ad hoc network routing protocols have been simulated to cover a range of design choices: Wireless Routing Protocol (WRP, Fisheye State Routing (FSR, Dynamic Source Routing (DSR, Ad hoc On-demand Distance Vector (AODV and Location Aided Routing (LAR. The protocols are evaluated in different environments to investigate performance metrics. Performance metric includes the following aspects: packets deliver ratio, end-to-end delay and end-to-end throughput.
Full Text Available Business Intelligence drives strategic business decisions by providing timely and accurateinformation. Beneath the demand for constantly changing information-needs usually lay a highly complexentangled mesh of business rules, data sets, query logic and custom-ad hoc Reports. The discrete natureof ad hoc reports may lead to inefficiencies in processing times and also valuable business knowledge isbeing lost. If the ad hoc queries are viewed within a context of larger collection of queries we couldderive meaningful information worthy of reuse. Expert Query System (EQS is an approach that drives adhoc queries towards standardization, structure and documentation to reuse, recycle queries, harnessknowledge and reduce the foot prints of the subsequent ad hoc queries. Therefore, a comprehensive, realtime, manageable, and knowledge-based solution for ad hoc reporting is absolutely necessary. Weproposed an expert query system based on a common metadata model that incrementally matures itselfand presents information to the users in relative terms to empower business intelligence solution.
Senthil Murugan Tamilarasan
Full Text Available Mobile Ad Hoc Network is one of the wireless network in which mobile nodes are communicate with each other and have no infrastructure because no access point. The MANET protocols can be classified as proactive and reactive routing protocol. The proactive routing protocols, all nodes which participated in network have routing table. This table updated periodically and is used to find the path between source and destination. The reactive routing protocol, nodes are initiate route discovery procedure when on-demand routes. In order to find the better route in MANET, many routing protocols are designed in the recent years. But those protocols are not concentrating about communication links and battery energy. Communication links between nodes and energy of nodes are very important factor for improving quality of routing protocols. This study presents innovative Link Stability with Energy Aware (LSEA multipath routing protocol. The key idea of the protocol is find the link quality, maximum remaining energy and lower delay. Reflections of these factors are increasing the qualities like packet delivery ratio, throughputs and reduce end-to-end delay. The LSEAMRP was simulated on NS-2 and evaluation results also shown.
Singh, Santosh Kumar
Spectrum is a scarce commodity, and considering the spectrum scarcity faced by the wireless-based service providers led to high congestion levels. Technical inefficiencies from pooled spectrum (this is nothing but the "common carrier principle" adopted in oil/gas/electricity pipelines/networks.), since all ad hoc networks share a common pool of channels, exhausting the available channels will force ad hoc networks to block the services. Researchers found that cognitive radio (CR) technology may resolve the spectrum scarcity. CR network proved to next generation wireless communication system that proposed as a way to reuse under-utilised spectrum of licensee user (primary network) in an opportunistic and non-interfering basis. A CR is a self-configuring entity in a wireless networking that senses its environment, tracks changes, and frequently exchanges information with their networks. Adding this layer of such intelligence to the ad hoc network by looking at the overall geography of the network known as cogni...
Vaishali D. Khairnar
Full Text Available A Vehicular Ad hoc Network (VANET consists of vehicles which communicate with each other and exchange data via wireless communication links available between the vehicles which are in communication ranges of vehicles to improve the road safety in city. The communication between vehicles is used to provide road safety, comfort and entertainment. The performance of communication depends on how better routing takes place in the network. Routing data between the source and destination vehicle depends on the routing protocols being used in vehicular ad-hoc network. In this simulation based study we investigated about different ad hoc routing protocols for vehicular ad-hoc network (VANET. The main goal of our study was to identify which ad hoc routing protocol has better performance in highly mobile environment of vehicular ad-hoc network. We have measured the performance of routing protocols using 802.11p in vehicular ad-hoc network in which we considered the scenario of city (i.e. Route between Nerul and Vashi where we have take 1200 different types of vehicles and checked their performance. Routing protocols are selected after the literature review. The selected protocols are then evaluated through simulation under 802.11p in terms of performance metrics (i.e PDR & E2E delay
Fetter, Sibren; Berlanga, Adriana; Sloep, Peter
Fetter, S., Berlanga, A. J., & Sloep, P. B. (2010, 3-4 May). Using Ad Hoc Transient Communities to Strengthen Social Capital: Design Considerations. Presented at the 7th International Conference on Networked Learning (NLC-2010), Aalborg, Denmark.
von Hofer, Hanns
This research note questions the common practice of ad hoc chart reading without formulating a sensible statistical model of the data beforehand and argues that the random walk model should not be overlooked when analyzing time series of crime data.
... include: Ad-Hoc Task Force on Planetary Defense Terms of Reference. NASA Near Earth Object (NEO) Program... will need to sign in and show a valid government-issued picture identification such as driver's...
Full Text Available Routing protocol to the wireless ad hoc networks is very needed in the communication process between some terminals, to send the data packet through one or several node(s to the destination address where the network typology is always changing. Many previous works that discussed about routing ad hoc both for manet (mobile ad hoc networks and wireless networks, but the emphasis have more focus on comparing the performance of several routing ad hoc. While in this work, there is a bulding of routing algorithm model to gateway in land to the nodes that analogized as a boat that move on the sea. With the assumption that the communication inter terminals to radio band of Very High Frequency, thus algorithm that built in the simulation based on the range gap of the HF frequency. The result of this simulation will be developed as the platform to implement the service development of multiuser communication
Full Text Available Due to the advancement in wireless technologies, many of new paradigms have opened for communications. Among these technologies, mobile ad hoc networks play a prominent role for providing communication in many areas because of its independent nature of predefined infrastructure. But in terms of security, these networks are more vulnerable than the conventional networks because firewall and gateway based security mechanisms cannot be applied on it. That’s why intrusion detection systems are used as keystone in these networks. Many number of intrusion detection systems have been discovered to handle the uncertain activity in mobile ad hoc networks. This paper emphasized on proposed fuzzy based intrusion detection systems in mobile ad hoc networks and presented their effectiveness to identify the intrusions. This paper also examines the drawbacks of fuzzy based intrusion detection systems and discussed the future directions in the field of intrusion detection for mobile ad hoc networks.
Moharram, Mohammed Morsi; Azam, Farzana
Vehicular ad hoc networks (VANETs) are one special type of ad hoc networks that involves vehicles on roads. Typically like ad hoc networks, broadcast approach is used for data dissemination. Blind broadcast to each and every node results in exchange of useless and irrelevant messages and hence creates an overhead. Unicasting is not preferred in ad-hoc networks due to the dynamic topology and the resource requirements as compared to broadcasting. Simple broadcasting techniques create several problems on privacy, disturbance, and resource utilization. In this paper, we propose media mixing algorithm to decide what information should be provided to each user and how to provide such information. Results obtained through simulation show that fewer number of keys are needed to share compared to simple broadcasting. Privacy is also enhanced through this approach. PMID:24587749
National Aeronautics and Space Administration — Aquilent, Inc. proposes to support ad-hoc, content-based query and data retrieval from virtual observatories (VxO) by developing 1) Higher Order Query Services that...
Zafoune, Youcef; kanawati, Rushed; 10.5121/ijcnc.2010.2213
This paper presents a new approach in the management of mobile ad hoc networks. Our alternative, based on mobile agent technology, allows the design of mobile centralized server in ad hoc network, where it is not obvious to think about a centralized management, due to the absence of any administration or fixed infrastructure in these networks. The aim of this centralized approach is to provide permanent availability of services in ad hoc networks which are characterized by a distributed management. In order to evaluate the performance of the proposed approach, we apply it to solve the problem of mobile code localization in ad hoc networks. A comparative study, based upon a simulation, of centralized and distributed localization protocols in terms of messages number exchanged and response time shows that the centralized approach in a distributed form is more interesting than a totally centralized approach.
Chiu, HS; Wong Lui, KS
In mobile ad hoc networks, data transmission is performed within an untrusted wireless environment. Various kinds of attack have been identified and corresponding solutions have been proposed. Wormhole attack is one of the serious attacks which forms a serious threat in the networks, especially against many ad hoc wireless routing protocols and location-based wireless security system. We identify two types of wormhole attacks. In the first type, malicious nodes do not take part in finding rou...
Xing Zhang; Bang Liu; Jinchuan Tang
Vehicles have the characteristic of high mobility which makes vehicular ad hoc networks (VANETs) different from other mobile ad hoc networks (MANETs), it is more difficult to establish an end-to-end route in VANETs, and the source and destination nodes keep moving fast from their original locations. To guarantee a data packet will finally be received by the destination node in VANETs, and the location of the destination node must be tracked constantly. Advanced Greedy Forwarding (AGF (Naumov ...
Shrikant Pujar; Prof. Vasudev K Parvati
In this Paper, We are dealing with the Current Qos Models for MANETs. We have proposed theExtension of Stateless Wireless Ad Hoc Network (SWAN) in order to improve Qos by using the schedulingModule Stateless network model which uses Rate Control Algorithm to deliver service differentiation inmobile wireless ad hoc network in a simple, scalable manner. In the Results we have shown the CongestionFree Routing between two different nodes of a Network through Router.
Caleffi, Marcello; Paura, Luigi
In this paper, a reliability analysis is carried out to state a performance comparison between two recently proposed proactive routing algorithms. These protocols are able to scale in ad hoc and sensor networks by resorting to dynamic addressing, to face with the topology variability, which is typical of ad hoc, and sensor networks. Numerical simulations are also carried out to corroborate the results of the analysis.
Melanie Jung; Georg Fischer; Robert Weigel; Thomas Ussmueller
This paper introduces the key elements of a novel low-power, high precision localization system based on Time-Difference-of-Arrival (TDOA) distance measurements. The combination of multiple localizable sensor nodes, leads to an ad hoc network. Besides the localization functionality this ad hoc network has the additional advantage of a communication interface. Due to this a flexible positioning of the master station for information collection and the detection of static and mobile nodes is pos...
Hadded, Mohamed; Muhlethaler, Paul; Zagrouba, Rachid; Laouiti, Anis; Saidane, Leila Azouz
—Vehicular ad hoc networks (VANETs) where vehicles act as mobile nodes is an instance of Mobile Ad hoc NETworks (MANETs), which are essentially developed for intelligent transportation systems. A challenging problem when designing communication protocols in VANETs is coping with high vehicle mobility, which causes frequent changes in the network topology and leads to frequent breaks in communication. The clustering technique is being developed to reduce the impact of mobility between neighbor...
Liu, Fei; Heijenk, Geert; Braun, Torsten; Carle, Georg; Fahmy, Sonia; Koucheryavy, Yevgeni
A novel approach to performing context discovery in ad-hoc networks based on the use of attenuated Bloom filters is proposed in this paper. In order to investigate the performance of this approach, a model has been developed. This document describes the model and its validation. The model has been implemented in Matlab, and some results are also shown in this document. Attenuated Bloom filters appear to be a very promising approach for context discovery in ad hoc networks.
Ad hoc networks are temporary networks with a dynamic topology which don t have any established infrastructure or centralized administration. Consequently, in recent years many researchers have focused on these networks. These networks need efficient routing protocols in terms of Quality of Services (QOS) metrics. Ad hoc networks suffer from frequent and rapid topology changes that cause many challenges in their routing. Most of the routing protocols like this proposed protocol try to find a ...
Franz, Walter; Hartenstein, Hannes; Mauve, Martin
Vehicular Ad Hoc Networks (VANETs) represent an emerging topic in wireless communication and networking. VANETs are currently receiving a lot of attention due to their promise of considerably increasing safety and comfort while being on the road. High mobility, adverse channel conditions, and market introduction are some of the key challenges one has to deal with when designing these spontaneous networks. Inter-Vehicle-Communications Based on Ad Hoc Networking Principles covers results and ac...
Füßler, Holger; Torrent-Moreno, Marc; Krüger, Roland; Transier, Matthias; Hartenstein, Hannes; Effelsberg, Wolfgang
While Mobile Ad-Hoc Networks are generally studied using a randomized node movement model such as the Random Way-Point model , Vehicular Ad-Hoc Networks deal with street-bound vehicles following a completely different movement pattern. This results - among other things - in a completely different connectivity situation and new challenges for data dissemination or routing/forwarding algorithms. Thus, researchers need a) suitable movement patterns for simulation, and b) a solid statistical u...
Sabah, Nasser M. A.
ABSTRACT: A mobile ad-hoc network (MANET) is a collection of wireless mobile nodes forming a temporary network without the need for base stations or any other preexisting network infrastructure. Ad-hoc networking received a great interest due to its low cost, high flexibility, fast network establishment, self-reconfiguration, high speed for data services, rapid deployment and support for mobility. However, in a wireless network without a fixed infrastructure and with nodes’ mobility enabl...
Badarneh OsamahS; Kadoch Michel
Abstract Multicasting plays a crucial role in many applications of mobile ad hoc networks (MANETs). It can significantly improve the performance of these networks, the channel capacity (in mobile ad hoc networks, especially single-channel ones, capacity is a more appropriate term than bandwidth, capacity is measured in bits/s and bandwidth in Hz) and battery power of which are limited. In the past couple of years, a number of multicast routing protocols have been proposed. In spite of being d...
Ismail Hababeh; Issa Khalil; Abdallah Khreishah; Samir Bataineh
Ad-hoc networks are talented but are exposed to the risk of wormhole attacks. However, a wormhole attack can be mounted easily and forms stern menaces in networks, particularly against various ad-hoc wireless networks. The Wormhole attack distorts the network topology and decrease the network systems performance. Therefore, identifying the possibility of wormhole attacks and recognizing techniques to defend them are central to the security of wireless networks as a whole. In this study, we wi...
Chirag Jain; Vikas Raghuwanshi
A Network which is form spontaneously by the collection of wireless nodes without any centralized administration or already existing network infrastructure called Mobile Ad-hoc Network (MANET). Performance evaluation of different Ad-Hoc networks routing protocols viz. DSDV, AODV & DSR on the basis of four parameter such as Packet delivery ratio, throughput, packet drop and routing overhead is main objective of this paper. NS-2, which is a discrete event simulation tool, is used in which T...
Qazi Javed Ahmed; Mirza Aamir Mehmood; Abdul Qudoos
Mobile ad hoc network (MANET) is an organization of static and wireless mobile nodes having no any central administration and fixed infrastructure. In MANET, each node can acts as routing and hosting device. Performance comparison and analysis has been conducted by using four different scenarios in NS2 (Network Simulator) for which two reactive (AODV, DSR) and two proactive (OLSR, DSDV) ad hoc routing protocols have been selected by utilizing 802.11 wireless standard. The main goal is to find...
Reshmi, B. M.; Manvi, S. S.; Bhagyavati
Intrusion detection has over the last few years, assumed paramount importance within the broad realm of network security, more so in case of wireless mobile ad hoc networks. The inherently vulnerable characteristics of wireless mobile ad hoc networks make them susceptible to attacks in-spite of some security measures, and it may be too late before any counter action can take effect. As such, there is a need to complement traditional security mechanisms with efficient intrusion detection and r...
Mitrokotsa, A.; Komninos, N.; Douligeris, C.
Mobile ad hoc networks have received great attention in recent years, mainly due to the evolution of wireless networking and mobile computing hardware. Nevertheless, many inherent vulnerabilities exist in mobile ad hoc networks and their applications that affect the security of wireless transactions. As intrusion prevention mechanisms, such as encryption and authentication, are not sufficient we need a second line of defense, Intrusion Detection. In this pa-per we present an intrusion detecti...
In VANET, or Intelligent Vehicular Ad-HocNetworking, defines an intelligent way of usingVehicular Networking. In VANET integrates onmultiple ad-hoc networking technologies such as WIFIIEEE 802.11p, WAVE IEEE 1609, WIMAX IEEE802.16, Bluetooth, IRA, and ZIGBEE for easy,accurate, effective and simple communication betweenvehicles on dynamic mobility. Effective measuressuch as media communication between vehicles canbe enabled as well as methods to track the automotivevehicles. In VANET helps in ...
Vaishali D. Khairnar; Kotecha, Dr. Ketan
A Vehicular Ad-hoc Network (VANET) is a collection of wireless vehicle nodes forming a temporary network without using any centralized Road Side Unit (RSU). VANET protocols have to face high challenges due to dynamically changing topologies and symmetric links of networks. A suitable and effective routing mechanism helps to extend the successful deployment of vehicular ad-hoc networks. An attempt has been made to compare the performance of two On-demand reactive routing protocols namely AODV ...
P. Seethalakshmi; M. J.A. Jude; Rajendran, G
Problem statement: Mobile Ad Hoc Network (MANET) is a collection of wireless mobile nodes that dynamically forms a network. Most of the existing ad-hoc routing algorithms select the shortest path using various resources. However the selected path may not consider all the network parameters and this would result in link instability in the network. The problems with existing methods are frequent route change with respect to change in topology, congestion as result of traffic and battery limitat...
Dhananjay Bisen; Sanjeev Sharma
In a mobile ad hoc network, temporary link failures and route changes occur frequently. With the assumption that all packet losses are due to congestion, TCP performs poorly in such an environment. There are many versions of TCP which modified time to time as per need. In this paper modifications introduced on TCP New Reno over mobile ad-hoc networks using calculation of New Retransmission Time out (RTO), to improve performance in term of congestion control. To calculate New RTO, adaptive bac...
Hatem S. A. Hamatta
Full Text Available Wireless Mobile Ad-Hoc Networks is one of the attractive research field that growing exponentially in the last decade. it surrounded by much challenges that should be solved the improve establishment of such networks. Failure of wireless link is considered as one of popular challenges faced by Mobile Ad-Hoc Networks (MANETs. As this type of networks does not require any pre-exist hardware. As well as, every node have the ability of roaming where it can be connected to other nodes dynamically. Therefore, the network internal structure will be unpredictably changed frequently according to continuous activities between nodes that simultaneously update network topology in the basis of active ad-hoc nature. This model puts the functionality of routing operation in crucial angle in the area of research under mobile adhoc network field due to highly dynamic nature. Adapting such kernel makes MANET indigence new routing techniques to settle these challenges. Thereafter, tremendous amount of routing protocols proposed to argue with ad-hoc nature. Thus, it is quite difficult to specify which protocols operate efficiently under different mobile ad-hoc scenarios. This paper examines some of the prominent routing protocols that are designed for mobile ad-hoc networks by describing their structures, operations, features and then comparing their various characteristics.
PrefaceAD HOC WIRELESS NETWORKSA Modular Cross Layer Architecture for Ad Hoc Networks, M. Conti, J. Crowcroft, G. Maselli, and G. TuriRouting Scalability in MANETs, J. Eriksson, S. Krishnamurthy and M. FaloutsosUniformly Distributed Algorithm for Virtual Backbone Routing in Ad Hoc Wireless Networks, D.S. KimMaximum Necessary Hop Count for Packet Routing in MANET, X. Chen and J. ShenEfficient Strategyproof Multicast in Selfish Wireless Networks, X.-Yang LiGeocasting in Ad Hoc and Sensor Networks, I. StojmenovicTopology Control for Ad hoc Networks: Present Solutions and Open Issues, C.-C. Shen a
Full Text Available The desire to be connected anytime and anywhere has led to the development of wireless networks, opening new vista of research in pervasive and ubiquitous computing. Mobile Ad Hoc Networks (MANETs use portable devices such as mobile phones, laptops or personal digital assistants (PDAs for spontaneous establishment of communication. Most existing research in the area of mobile Ad Hoc Networks is limited to stand-alone isolated networks. But connectivity of a mobile Ad Hoc network to the Internet is also desirable as more and more applications and services in our society now depend on fixed infrastructure networks. It is therefore important that dynamically deployed wireless Ad Hoc networks should also gain access to these fixed networks and their services. The integration of MANETs into Internet increases the networking flexibility and coverage of existing infrastructure networks. Although researchers have proposed many solutions, but it is still unclear which one offer the best performance compared to the others. When an Ad Hoc network is connected to Internet, it is important for the mobile nodes to detect efficiently available Internet gateways providing access to the Internet. Internet gateway discovery time and handover delay have strong influence on packet delay and throughput. The key challenge in providing connectivity is to minimize the overhead of mobile IP and Ad Hoc routing protocol between Internet and Ad Hoc networks. There, this paper focuses on proposed technical solutions on Internet gateway discovery and also we briefly describe different ways to provide global Internet access for MANETs. Finally, some challenges are also mentioned which need in depth investigation.
The May 26, 1999 Resolution of the Joint Meeting of the Board of the Radiation Diagnosis and Radiation Therapy Section, Academic Council, Ministry of Health of Russia, the X-ray Diagnosis Ad Hoc Commission, Interdepartmental Scientific Council for Medical Radiology and Radiation Medicine, Russian Academy of Medical Sciences, and the Executive Committee, Russian Association of Radiologists
The text of the May 26, 1999 Resolution of the joint meeting of the Board of the Radiation Diagnosis and Radiation Therapy Section of the Ministry of Health of Russia with the X-ray Diagnostics Ad Hoc Problem Commission of the Intergovernmental Scientific Council for Medical Radiology and Radiation Medicine of the Russian Academy of Medical Sciences and the Executive Committee of Russian Association of Radiologists is presented. It is noted that in spite of the fact that the intervention radiology as an independent branch has not yet been formed, separate developments, aimed at application of invasive interventions under the control of radiodiagnostic methods are carried out in the area of bronco pulmonology, gastroenterology, mammology, gynecology, urology, oncology above 30 years and steps in legalization of this trend are also undertaken. Absence of statistical documentation on technical and staff provision of therapeutical-prophylactic establishments as well as unified terminology is noted. The tasks aimed at broader introduction of intervention radiology in Russia are set up
Full Text Available Mobile Ad-hoc Networks consist of wireless host that communicate with each other. The routes in a Mobile Ad-hoc Network may consist of many hops through other hosts between source and destination. The hosts are not fixed in a Mobile Adhoc Network; due to host mobility topology can change any time. Mobile Ad-hoc Networks are much more vulnerable to security attacks. Current research works on securing Mobile Adhoc Networks mainly focus on confidentiality, integrity,authentication, availability, and fairness. Design of routingprotocols is very much crucial in Mobile Ad-hoc Network. There are various techniques for securing Mobile Ad-hoc Network i.e. cryptography. Cryptography provides efficient mechanism to provide security, but it creates very much overhead. So, an approach is used which is analogous to Biological Immune System, known as Artificial Immune System (AIS. There is a reason of AIS to be used for security purposes because the Human Immune System (HIS protects the body against damage from an extremely large number of harmfulbacteria, viruses, parasites and fungi, termed pathogens. It doesthis largely without prior knowledge of the structure of thesepathogens. AIS provide security by determining non-trusted nodes and eliminate all non-trusted nodes from the network.
R. S.D. Wahida Banu
Full Text Available Problem statement: In mobile ad hoc networks there are a number of challenges in providing quality of service routing with energy efficiency and load balancing. Most routing protocols do not consider the problem of load balance. A routing protocol called energy Efficient Ad-hoc on Demand Vector (E2AODV is proposed. It addresses the quality of service issues such as throughput, end to end delay, load distribution and energy. Approach: This study presents a scheme to balance the load with energy efficiency considering both congestion and the nodes energy usage. A threshold value was used to judge if intermediate node was overloaded, variable and changing along with nodes interface queue length around the backward path. Results: The routing protocol called energy Efficient Ad hoc on Demand Vector (E2AODV that is intended to provide a reliable transmission with low energy consumption was compared with Ad-hoc on Demand Vector (AODV in terms of the packet delivery ratio, average end to end delay, load distribution and node energy consumption. Conclusion/Recommendation: E2AODV protocol chooses an optimum path with low energy usage. It provides a better scheme to balance the load with energy efficiency and packet delivery ratio. It can be further enhanced as a secure routing protocol for mobile ad-hoc networks.
Ansari, Imran Shafique
In ad hoc networks nodes cooperate with each other to form a temporary network without the aid of any centralized administration. No wired base station or infrastructure is supported, and each host communicates via radio packets. Each host must act as a router, since routes are mostly multi-hop, due to the limited power transmission set by government agencies, (e.g. the Federal Communication Commission (FCC), which is 1 Watt in Industrial Scientific and Medical (ISM) band. The natures of wireless mobile ad hoc networks depend on batteries or other fatiguing means for their energy. A limited energy capacity may be the most significant performance constraint. Therefore, radio resource and power management is an important issue of any wireless network. In this paper, a design for traffic light system employing ad hoc networks is proposed. The traffic light system runs automatically based on signals sent through a multi-hop ad hoc network of \\'n\\' number of nodes utilizing the Token Ring protocol, which is efficient for this application from the energy prospective. The experiment consists of a graphical user interface that simulates the traffic lights and laptops (which have wireless network adapters) are used to run the graphical user interface and are responsible for setting up the ad hoc network between them. The traffic light system has been implemented utilizing A Mesh Driver (which allows for more than one wireless device to be connected simultaneously) and Java-based client-server programs. © 2009 IEEE.
Full Text Available Multimedia data are becoming popular in wireless ad hoc environments. However, the traditional content-based retrieval techniques are inefficient in ad hoc networks due to the multiple limitations such as node mobility, computation capability, memory space, network bandwidth, and data heterogeneity. To provide an efficient platform for multimedia retrieval, we propose to cluster ad hoc multimedia databases based on their semantic contents, and construct a virtual hierarchical indexing infrastructure overlaid on the mobile databases. This content-aware clustering scheme uses a semantic-aware framework as the theoretical foundation for data organization. Several novel techniques are presented to facilitate the representation and manipulation of multimedia data in ad hoc networks: 1 using concise distribution expressions to represent the semantic similarity of multimedia data, 2 constructing clusters based on the semantic relationships between multimedia entities, 3 reducing the cost of content-based multimedia retrieval through the restriction of semantic distances, and 4 employing a self-adaptive mechanism that dynamically adjusts to the content and topology changes of the ad hoc networks. The proposed scheme is scalable, fault-tolerant, and efficient in performing content-based multimedia retrieval as demonstrated in our combination of theoretical analysis and extensive experimental studies.
An ad-hoc wireless network is a collection of nodes that come together to dynamically create a network, with no fixed infrastructure or centralized administration. An ad-hoc network is characterized by energy constrained nodes, bandwidth constrained links and dynamic topology. With the growing use of wireless networks (including ad-hoc networks) for real-time applications, such as voice, video, and real-time data, the need for Quality of Service (QoS) guarantees in terms of delay, bandwidth, and packet loss is becoming increasingly important. Providing QoS in ad-hoc networks is a challenging task because of dynamic nature of network topology and imprecise state information. Hence, it is important to have a dynamic routing protocol with fast re-routing capability, which also provides stable route during the life-time of the flows. In this thesis, we have proposed a novel, energy aware, stable routing protocol named, Stability-based QoS-capable Ad-hoc On-demand Distance Vector (SQ-AODV), which is an enhancement...
王秀芝; 石志东; 房卫东; 张小珑; 单联海
无线 Ad hoc 网络（MANET）的多跳、自组织、无固定设施以及运算资源有限等特性，使得传统网络中复杂度高的安全算法难以应用于其中。而采用与匿名技术相结合的安全机制，可较好地解决节点隐私和通信关系保密的安全问题。针对现有的匿名技术，采用对比分析的方法，对传统网络的匿名技术进行分析，总结技术上的优缺点，研究 Ad hoc 网络的匿名技术，并对比分析各种匿名通信协议的安全性能，为后续的研究与应用提供帮助。%Due to the features of Ad hoc networks such as multi-hop,self-organisation,non-infrastructure and limited resource,the security algorithms with high complexity in traditional networks are hard to be used in it.However to use the security mechanism combining with anonymous technology can well solve the security problem in regard to nodes’privacy and communication relationship secret.In this paper,targeted at existing anonymous technologies,we analyse their use in traditional networks with the method of comparative analysis, summarise the advantages and disadvantages in terms of technology,and meanwhile study the anonymous technologies used in Ad hoc networks,as well as compare and analyse the security performances of various anonymous communication protocol,these provide the help for subsequent researches and applications.
Full Text Available Mobile Ad hoc Networks are characterized by multi-hop wireless links, without any infrastructure and frequent node mobility. A class of ant colony based routing protocols has recently gained attention because of their adaptability to the network changes. AntHocNet is ant colony based hybrid algorithm, which combines reactive path setup with proactive path probing, maintenance and improvement. Multi-path routing represents a promising routing method for mobile ad hoc network. Multi-path routing achieves load balancing and is more resilient to route failures. This research introduces node disjoint multi-path property to AntHocNet routing algorithm. A virtual class room is one that can be established by using mobile devices and whose members can be dynamically added or removed. The implementation of virtual class room for lesson handling and query discussion using mobile ad hoc network is analyzed. The data are spread among the N (here N = 3 node disjoint routes from the beginning of the data transmission session. The performance metrics, average end-to-end delay, packet delivery ratio and load balancing have been analyzed for various pause times. The average end-to-end delay and packet delivery ratio have not varied significantly. Optimal load distribution is achieved by spreading the load among different node disjoint routes.
Krause, Wolfram; Glauche, Ingmar; Sollacher, Rudolf; Greiner, Martin
As a representative of a complex technological system, the so-called wireless multihop ad hoc communication networks are discussed. They represent an infrastructure-less generalization of todays wireless cellular phone networks. Lacking a central control authority, the ad hoc nodes have to coordinate themselves such that the overall network performs in an optimal way. A performance indicator is the end-to-end throughput capacity. Various models, generating differing ad hoc network structure via differing transmission power assignments, are constructed and characterized. They serve as input for a generic data traffic simulation as well as some semi-analytic estimations. The latter reveal that due to the most-critical-node effect the end-to-end throughput capacity sensitively depends on the underlying network structure, resulting in differing scaling laws with respect to network size.
Mann Raminder P
Full Text Available Wireless ad hoc sensor networks differ from wireless ad hoc networks from the following perspectives: low energy, lightweight routing protocols, and adaptive communication patterns. This paper proposes an energy-aware routing protocol (EARP suitable for ad hoc wireless sensor networks and presents an analysis for its energy consumption in various phases of route discovery and maintenance. Based on the energy consumption associated with route request processing, EARP advocates the minimization of route requests by allocating dynamic route expiry times. This paper introduces a unique mechanism for estimation of route expiry time based on the probability of route validity, which is a function of time, number of hops, and mobility parameters. In contrast to AODV, EARP reduces the repeated flooding of route requests by maintaining valid routes for longer durations.