WorldWideScience

Sample records for multimedia broadcast multicast

  1. Effective Radio Resource Management for Multimedia Broadcast/Multicast Services in UMTS Networks

    Directory of Open Access Journals (Sweden)

    Soares Armando

    2006-01-01

    Full Text Available Broadcast and multicast offer a significant improvement of spectrum utilization, and become particularly important where information channels are shared among several users. Mobile cellular environments are expected to evolve with the technological approaches necessary to facilitate the deployment of multimedia services, such as streaming, file download, and carousel services. The perspective that video streaming in wireless networks services is an attractive service to end-users has spurred the research in this area. To provide for a video delivery platform in UMTS, the third generation partnership project (3GPP addressed this problem with the introduction of the multimedia broadcast and multicast services (MBMS in 3GPP Release 6. In this document we analyse several effective radio resource management techniques to provide MBMS, namely, use of nonuniform QAM constellations, multicode, and macrodiversity to guarantee the optimal distribution of QoS depending on the location of mobiles.

  2. An enhanced framework for providing multimedia broadcast/multicast service over heterogeneous networks

    Institute of Scientific and Technical Information of China (English)

    Yi-han XU; Chee-Onn CHOW; Mau-Luen THAM; Hiroshi ISHII

    2014-01-01

    Multimedia broadcast multicast service (MBMS) with inherently low requirement for network resources has been proposed as a candidate solution for using such resources in a more efficient manner. On the other hand, the Next Generation Mobile Network (NGMN) combines multiple radio access technologies (RATs) to optimize overall network performance. Handover performance is becoming a vital indicator of the quality experience of mobile user equipment (UE). In contrast to the conventional vertical handover issue, the problem we are facing is how to seamlessly transmit broadcast/multicast sessions among heterogeneous networks. In this paper, we propose a new network entity, media independent broadcast multicast service center (MIBM-SC), to provide seamless handover for broadcast/multicast sessions over heterogeneous networks, by extensions and enhancements of MBMS and media independent information service (MIIS) architectures. Additionally, a network selection scheme and a cell transmission mode selection scheme are proposed for selecting the best target network and best transmission mode. Both schemes are based on a load-aware network capacity estimation algorithm. Simulation results show that the pro-posed approach has the capability to provide MBMS over heterogeneous networks, with improved handover performance in terms of packet loss rate, throughput, handover delay, cell load, bandwidth usage, and the peak signal-to-noise ratio (PSNR).

  3. Cross-layer design of LT codes and LDPC codes for satellite multimedia broadcast/multicast services

    Institute of Scientific and Technical Information of China (English)

    Wang Zhenbang; Wang Zhenyong; Gu Xuemai; Guo Qing

    2013-01-01

    According to large coverage of satellites, there are various channel states in a satellite broadcasting network. In order to introduce an efficient rateless transmission method to satellite multimedia broadcasting/multicast services with finite-length packets, a cross-layer packet transmis-sion method is proposed with Luby transform (LT) codes for efficiency in the network layer and low density parity check (LDPC) codes for reliability in the physical layer jointly. The codewords gen-erated from an LT encoder are divided into finite-length packets, which are encoded by an LDPC encoder subsequently. Based on noise and fading effects of satellite channels, the LT packets received from an LDPC decoder either have no error or are marked as erased, which can be mod-eled as a binary erasure channels (BECs). By theoretical analysis on LT parameters and LDPC parameters, the relationships between LDPC code rates in the physical layer and LT codes word lengths in the network layer are investigated. With tradeoffs between the LT codes word lengths and the LDPC code rates, optimized cross-layer solutions are achieved with a binary search algo-rithm. Verified by simulations, the proposed solution for cross-layer parameters design can provide the best transmission mode according to satellite states, so as to improve throughput performance for satellite multimedia transmission.

  4. Transmission techniques for emergent multicast and broadcast systems

    CERN Document Server

    da Silva, Mario Marques; Dinis, Rui; Souto, Nuno; Silva, Joao Carlos

    2010-01-01

    Describing efficient transmission schemes for broadband wireless systems, Transmission Techniques for Emergent Multicast and Broadcast Systems examines advances in transmission techniques and receiver designs capable of supporting the emergent wireless needs for multimedia broadcast and multicast service (MBMS) requirements. It summarizes the research and development taking place in wireless communications for multimedia MBMS and addresses the means to improved spectral efficiency to allow for increased user bit rate, as well as increased capacity of the digital cellular radio network.The text

  5. Multimedia Conferencing System and Multicasting

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The multimedia conferencing system is an important tool for Computer-supported Cooperative Work (CSCW), and also one of the basic techniques supporting team work in the Concurrent Engineering. In this paper the architecture and function modules of the reported multimedia conferencing system are described. Then in order to reduce the network bandwidth required by the conferencing system, two methods for sending the conferencing data by using multicasting are discussed.

  6. Multimedia multicast on the Internet

    CERN Document Server

    Benslimane, Abderrahim

    2010-01-01

    This book examines multicast technology and will be a key text for undergraduate engineering students and master students in networks and telecoms. However, it will be equally useful for a wide range of professionals in this research field. Multicast routing was introduced with the advent of multiparty applications (for example, videoconferencing on the Internet) and collaborative work (for example, distributed simulations). It is related to the concept of group communication, a technique introduced to reduce communication costs. The various problems of multicast routing on the Internet are

  7. IP MULTICAST GROUP MANAGEMENT FOR BROADCAST LANS DISTRIBUTION

    Institute of Scientific and Technical Information of China (English)

    阿姆贾德

    2001-01-01

    Problems of the current IGMP mechanism were identified, such as unnecessary periodic probing of hosts and leave latency, which wastes bandwidth and cause more traffic and overhead. Alternative mechanism that preserve the IP multicast model but employ join/leave messages to track local group membership for broadcast LANs (shared medium LANs) was proposed in this paper. We describe the implementation requirements of the new mechanism and compare it to existing one, demonstrating that join/leave approach is uniformly superior for the environment of broadcast LANs.

  8. Distributed multicast routing algorithm with dynamic performance in multimedia networks

    Institute of Scientific and Technical Information of China (English)

    Zhu Baoping; Zhang Kun

    2009-01-01

    Tbe delay and DVBMT problem is known to be NP-complete. In this paper, an efficient distributed dynamic multicast muting algorithm was proposed to produce muting trees with delay and delay variation constraints. The pro-posed algorithm is fully distributed, and supports the dynamic reorganizing of the muhicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and muting success ratio as compared with other existing algorithms, and performs excellently in delay variation performance under lower time complexity, which ensures it to support the requirements of real-time multimedia communications more effectively.

  9. All-optical broadcast and multicast technologies based on PPLN waveguide

    DEFF Research Database (Denmark)

    Ye, Lingyun; Wang, Ju; Hu, Hao

    2013-01-01

    All-optical 1×4 broadcast and 1×3 multicast experiments of a 40-Gb/s return-to-zero on-off keying (RZ-OOK) signal based on a periodically poled lithium niobate (PPLN) waveguide are demonstrated in this letter. Clear opened eye diagrams and error-free performance are achieved for the broadcast...

  10. Optimizing Energy and Modulation Selection in Multi-Resolution Modulation For Wireless Video Broadcast/Multicast

    KAUST Repository

    She, James

    2009-11-01

    Emerging technologies in Broadband Wireless Access (BWA) networks and video coding have enabled high-quality wireless video broadcast/multicast services in metropolitan areas. Joint source-channel coded wireless transmission, especially using hierarchical/superposition coded modulation at the channel, is recognized as an effective and scalable approach to increase the system scalability while tackling the multi-user channel diversity problem. The power allocation and modulation selection problem, however, is subject to a high computational complexity due to the nonlinear formulation and huge solution space. This paper introduces a dynamic programming framework with conditioned parsing, which significantly reduces the search space. The optimized result is further verified with experiments using real video content. The proposed approach effectively serves as a generalized and practical optimization framework that can gauge and optimize a scalable wireless video broadcast/multicast based on multi-resolution modulation in any BWA network.

  11. Advanced Broadcast/Multicast Channel Capable Carrier Reuse WDM-PON

    Directory of Open Access Journals (Sweden)

    Ashish Nema

    2013-02-01

    Full Text Available Advanced broadcast/multicast carriers reuse WDM-PON is mainly used to provide the broadcast and unicast signal at the destination end. It uses the splitting capability of a power splitter and the cyclic property of arrayed waveguide grating at the middle remote node. The broadcast channel with the help of AWG and with a dedicated unicast channel can be overlaid and subsequently transmitted to each Optical network unit (ONU simultaneously. Another advantage of this WDM-PON a very small interface between the broadcast channel and with the unicast channel and it is shared by all ONU. The optical carrier to subcarrier ratio on the bit error rate performance can be minimized by increasing the extinction ratio of the delay interferometer used at remote node. The result is implemented by opti-system 7.0 software tools

  12. China formally issued mobile multimedia broadcasting industry standard

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ October 24, 2006, China SARFT (State Administration of Radio Film and Television) formally issued the China mobile multimedia broadcasting (namely,Mobile TV) industry standard. The standard is a STiMi standard self-developed in China and put into practice from November 1 this year.

  13. Vast Educational Mobile Content Broadcasting using ARMrayan Multimedia Mobile CMS

    CERN Document Server

    Fatahi, Somayeh; Jahromi, Zahra Forootan

    2010-01-01

    The huge information flow currently available to young generation makes it difficult for educational centers to train them as needed. Most of these information flows occur in transportation time or while on public areas. Competing with commercial information streams is far out of educational centers time and budget. For creating enough mobile applications for vast educational mobile content broadcasting that can match young spirits as well, we designed and developed the ARMrayan Multimedia Mobile CMS as the software that helps communities, educational, cultural or marketing centers in a way that ordinary operators be able to create a variety of fully functional multimedia mobile applications such as tutorials, catalogues, books, and guides in minutes without writing even a line of code. In this paper, we present the role of our developed software in our proposed vast educational content broadcasting system using kiosks and Bluetooth advertising, which will lead to a great leap in M-commerce marketing and publ...

  14. Vast Educational Mobile Content Broadcasting using ARMrayan Multimedia Mobile CMS

    OpenAIRE

    2010-01-01

    The huge information flow currently available to young generation makes it difficult for educational centers to train them as needed. Most of these information flows occur in transportation time or while on public areas. Competing with commercial information streams is far out of educational centers time and budget. For creating enough mobile applications for vast educational mobile content broadcasting that can match young spirits as well, we designed and developed the ARMrayan Multimedia Mo...

  15. Multicast Services of QoS-Aware Active Queue Management over IP Multimedia Applications

    Science.gov (United States)

    Hwang, I.-Shyan; Hwang, Bor-Jiunn; Chang, Pen-Ming

    2010-10-01

    Recently, the multimedia services such as IPTV, video conference emerges to be the main traffic source. When UDP coexists with TCP, it induces not only congestion collapse but also unfairness problem. In this paper, a new Active Queue Management (AQM) algorithm, called Traffic Sensitive Active Queue Management (TSAQM), is proposed for providing multimedia services. The TSAQM comprise Dynamic Weight Allocate Scheme (DWAS) and Service Guarantee Scheme (SGS), the purpose of DWAS is to allocate resource with fairness and high end-user utility, and the purpose of SGS is to determine the satisfactory threshold (TH) and threshold region (TR). Several objectives of this proposed scheme include achieving high end-user utility for video service, considering the multicast as well as unicast proprieties to meet inter-class fairness and achieving the QoS requirement by adjusting the thresholds adaptively based on traffic situations.

  16. Dynamic Reconfiguration of IP Domain Middleware Stacks to Support Multicast Multimedia Distribution in a Heterogeneous Environment

    Directory of Open Access Journals (Sweden)

    Kevin Curran

    2005-01-01

    Full Text Available Seamless connectivity to multiple wireless networks independently of a fixed point is becoming increasingly important for mobile devices however wireless networks differ in bandwidth, size and access costs each requiring protocol functions to enable devices to communicate efficiently. In addition, due to the divergence of users and applications, traditional stacks are frequently enriched with additional functionality such as transport protocol functionality, synchronisation and presentation coding which can lead to a performance bottleneck due to the insufficient processing power and memory of portable devices. We argue that an extensible middleware is needed to cover small resource constrained devices to full-fledged desktop computers thus we investigate dynamic micro-protocols which enable devices to adopt specific protocol stacks at runtime in an attempt to optimise the stack to the functionality that is actually required by the application thus eliminating additional overhead functionality provided by generic stacks. A side effect of this is that it allows devices such as PDAs to offer protocol functions, which would not normally be available due to their memory constraints. Memory constrained devices are catered for through the deployment of a client-proxy overlay network where proxies offload processing. The problem of the ?common denominator bandwidth? is overcome through multicast media groups where clients subscribe to different quality of services in accordance with resource availability and move between groups according to bandwidth availability over time. Our end result is a Java middleware for multimedia streaming to heterogeneous mobile clients, utilising dynamic configuration of protocols with respect to application requirements and available network resources. Performance is increased through application specific tailored protocols and reducing protocol complexity allows stacks to fit inside the limited memory space of current

  17. 量子隐形传态网络的广播与组播%Broadcast and multicast in quantum teleportation internet

    Institute of Scientific and Technical Information of China (English)

    周小清; 邬云文

    2012-01-01

    The physical principle of broadcast and multicast is given. When Alice needs to send out an information, she sends out a conjunction claim signal to the switch that connects with hers. After receiving the conjunction claim the signal, the switch pass to examines the purpose address to judge whether it is a point-to-point communication or broadcast and multicast. If the purpose address is A or B or C address, then the switch carries on the correspondence operation of point-to-point; if the purpose address is a D address or an address (local or appointed network webcasting) with special meaning, then the switch carries on the correspondence operation of broadcast and multicast. With broadcast and multicast, the fidelity decreases with the increase of receiving terminal number, and its limit is 2/3.%给出了广播与组播的物理原理.当Alice需要发送信息时,就向与自己相连的交换机发送一连接请求信号,交换机收到连接请求信号后通过检测目的地址判断是点到点的通信还是组播与广播;若目的地址是A类、B类或C类地址,则进行点到点的通信操作;若目的地址是D类地址或是有特殊意义的地址(本地网络,指定网络广播),则启动量子信息的广播与组播操作.广播与组播时的保真度随受话终端数的增加而减小,其极限为2/3.

  18. A Source-Based Multicast Scheme in IEEE 802.16 Mesh Mode

    Directory of Open Access Journals (Sweden)

    Ali Azarpeyvand

    2012-12-01

    Full Text Available WiMAX based on IEEE 802.16 is known as one of effective technologies for transmission of multimedia to groups of receivers. There are two operational modes in WiMAX: point to multi point (PMP for single hop transmission and a mesh node for multi-hop transmission. The current standard only defines unicast transmission under mesh mode thus the performance is deteriorated for multimedia applications with multicast nature. In this paper, we first propose a mechanism for source-based tree topology construction aiming at facilitating multicast transmission in WiMAX mesh network. In the proposed approach, the multicast tree is constructed considering available link’s bandwidth and multicast group members. After constructing the multicast tree we propose a novel scheduling algorithm to improve the transmission throughout. In the proposed scheduling algorithm a parent node uses broadcasting when the number of its children belonging to a multicast group excesses a threshold. Extensive simulation results show that the proposed multicast mechanism improves multicast transmission efficiency and reduces scheduling time slots noticeably in comparison to the approach mandated by the IEEE 802.16 standard.

  19. Performance evaluation of Eureka-147 with RS(204, 188) code for mobile multimedia broadcasting

    Science.gov (United States)

    Chang, Seung-Gi; Ha, Victor H. S.; Zhang, Zhiming; Kim, Yongje

    2003-06-01

    The demand for mobile multimedia broadcasting service is increasing consistently as more people expect seamless outdoor connections and communication capabilities. In this paper, we introduce the digital multimedia broadcasting (DMB) system based on Eureka-147 that has been tentatively adopted in Korea. Since Eureka-147 is originally designed for broadcasting digital audio data, it provides a bit error rate (BER) of about 10-4 while the transmission of compressed video data, for example, requires the BER of about 10-9. To deal with this mismatch, the Korean DMB standard is considering the addition of the RS(204,188) coder to Eureka-147. In this paper, we apply the RS(204,188) coder to the Eureka-147 and present the simulation results on the performance of this modified system at various transmission and protection modes. We conclude that the addition of RS(204,188) coder to Eureka-147 in the Korean DMB system results in the satisfactory level of BER for mobile multimedia broadcasting services.

  20. Design of an Advertisement Scenario for Electric Vehicles Using Digital Multimedia Broadcasting

    Science.gov (United States)

    Lee, Junghoon; Kim, Hye-Jin; Shin, In-Hye; Cho, Jason; Lee, Sang Joon; Kwak, Ho-Young

    This paper designs an integrative advertisement system based on digital multimedia broadcasting for the electric vehicles, which need a lot of driving information for battery efficiency and charge planning. The advertiser interface interacts with the advertisement processing system to pay the fee and have the contents endorsed. The advertisement contents are registered, monitored, encoded, and finally delivered to vehicles according to the contract via the broadcasting center. Here, this paper defines a new frame format on the data service stream and is in the process of developing and verifying the encoder and decoder modules. Our system is expected to provide the fundamentals for the development of diverse electric vehicle services.

  1. Performance and Rekeying Analysis of Multicast Security in LTE

    Directory of Open Access Journals (Sweden)

    Mohsen M. Tantawy

    2013-07-01

    Full Text Available Multimedia Broadcast Multicast Services (MBMS is apoint-to-multipointinterface specification forexisting and upcoming3GPPcellular networks, which is designed to provide efficient delivery ofbroadcastandmulticastservices, within a cellorwithin the core network. Target applications includemobile TVandradio broadcasting, file delivery and emergency alerts.Themain goal of this paper is to assess theperformance of the Secure Multicast Overlay (SMO and the Group Security Association (GSA. Wefunctionally compare GSA with SMO, in terms of Keys management procedures and look up policiesshowing that GSAsolution is appropriate in certain circumstances and SMO solution is appropriate inothers. The comparison will be for different parameters and different services.Also the computational costand storage cost forLogical Key Hierarchy (LKHtreewith and without dynamicrekeying willbecalculated.

  2. IP over optical multicasting for large-scale video delivery

    Science.gov (United States)

    Jin, Yaohui; Hu, Weisheng; Sun, Weiqiang; Guo, Wei

    2007-11-01

    In the IPTV systems, multicasting will play a crucial role in the delivery of high-quality video services, which can significantly improve bandwidth efficiency. However, the scalability and the signal quality of current IPTV can barely compete with the existing broadcast digital TV systems since it is difficult to implement large-scale multicasting with end-to-end guaranteed quality of service (QoS) in packet-switched IP network. China 3TNet project aimed to build a high performance broadband trial network to support large-scale concurrent streaming media and interactive multimedia services. The innovative idea of 3TNet is that an automatic switched optical networks (ASON) with the capability of dynamic point-to-multipoint (P2MP) connections replaces the conventional IP multicasting network in the transport core, while the edge remains an IP multicasting network. In this paper, we will introduce the network architecture and discuss challenges in such IP over Optical multicasting for video delivery.

  3. Online scene change detection of multicast (MBone) video

    Science.gov (United States)

    Zhou, Wensheng; Shen, Ye; Vellaikal, Asha; Kuo, C.-C. Jay

    1998-10-01

    Many multimedia applications, such as multimedia data management systems and communication systems, require efficient representation of multimedia content. Thus semantic interpretation of video content has been a popular research area. Currently, most content-based video representation involves the segmentation of video based on key frames which are generated using scene change detection techniques as well as camera/object motion. Then, video features can be extracted from key frames. However most of such research performs off-line video processing in which the whole video scope is known as a priori which allows multiple scans of the stored video files during video processing. In comparison, relatively not much research has been done in the area of on-line video processing, which is crucial in video communication applications such as on-line collaboration, news broadcasts and so on. Our research investigates on-line real-time scene change detection of multicast video over the Internet. Our on-line processing system are designed to meet the requirements of real-time video multicasting over the Internet and to utilize the successful video parsing techniques available today. The proposed algorithms extract key frames from video bitstreams sent through the MBone network, and the extracted key frames are multicasted as annotations or metadata over a separate channel to assist in content filtering such as those anticipated to be in use by on-line filtering proxies in the Internet. The performance of the proposed algorithms are demonstrated and discussed in this paper.

  4. Application-Network Cross Layer Multi-variable Cost Function for Application Layer Multicast of Multimedia Delivery over Convergent Networks

    OpenAIRE

    Le, Tien Anh; Nguyen, Hang; Nguyen, Manh Cuong

    2015-01-01

    International audience; Application layer multicast (ALM) algorithms are either similar or conceptually based on network layer multicast's cost functions. In this research work, a new application-network cross layer multi-variable cost function is proposed. It optimizes the variable requirements and available resources from both the application and the network layers. It can dynamically update the available resources required for reaching a particular node on the ALM's media distribution tree...

  5. Programming Technology of IP Multicast and Broadcast Based on Socket%基于套接字的IP多目通信及广播通信编程技术

    Institute of Scientific and Technical Information of China (English)

    李冬霞; 苏广川; 沈瑛

    2001-01-01

    Beginning with the simple introduction of socket which is the most commonly used application program interfaces in UNIX/LINUX communication domain, the concrete programming procedures to realize multicast and broadcast based on socket is provided, according to TCP/IP protocol in LINUX system. The acquiring and converting of broadcast destination address and multicast address, the setting of multicast options, the joining in and withdrawing from the multicast group, and the receiving and sending of datagram are all demonstrated in it, the related system calls and simple explication of C programming are also included.%简单介绍了UNIX/LINUX通信域中最常用的应用程序接口——套接字,在此基础上,详细描述了在LINUX系统中按照TCP/IP协议,实现基于套接字的多目通信、广播通信的具体编程步骤,包括广播目的地址、多目地址的获取与转换,多目通信中特征选项的设置,多目组的加入与退出,报文的发送与接收等,同时也给出了相关的系统调用及程序段说明.

  6. Membangun Server Multicast Berbasis Streaming Menggunakan Centos

    Directory of Open Access Journals (Sweden)

    Irwan Susanto

    2009-11-01

    Full Text Available The development of IP-based technology contribute to the development of telecomunication and information technology.  One of  IP-based technology application is streaming multicast, as part of broadcasting. The streaming  process is made by accessing  Telkom-2 broadcast  through AKATEL LAN network, then  server forward it to clients using multicast IP system. Multicast IP is D-class IP, which is able to send data package in realtime. In multicast system, server only send one data package to  some clients with same speed transmition. The Telkom-2 broadcast is already accessed before   sent as data package. Server will access Telkom-2 broadcast using parabola antenna and Hughes modem, then forward it to clients through AKATEL LAN network. Clients must conect to server via AKATEL LAN network and already  instaled VLC player, in order to be able to access the Telkom-2 broadcast

  7. One Way Multimedia Broadcasting as a Tool for Education and Development in Developing Nations

    Science.gov (United States)

    Chandrasekhar, M. G.; Venugopal, D.; Sebastian, M.; Chari, B.

    2000-07-01

    An improved quality of life through education and developmental communication is an important necessity of societal up-liftment in the new millennium, especially in the developing nations. The population explosion and the associated pressure on the scarce resources to meet the basic necessities have made it more or less impossible for most of the nations to invest reasonable resources in realizing adequate channels of formal education. Thanks to the developments in satellite communication and associated technologies, new vistas are available today to provide education and developmental communication opportunities to millions of people, spread across the globe. Satellite based Digital Audio and Multimedia Broadcasting is one such new development that is being viewed as an innovative space application in the coming decades. The potential of DAB technology to reach education, information and entertainment directly to the user through a specially designed receiver could be efficiently utilized by the developing nations to overcome their difficulties in realizing formal channels of education and information dissemination. WorldSpace plans to launch three geo-stationary satellites that would cover most of the developing economies in Africa, the Mediterranean, the Middle East, Asia, Latin America and the Caribbean. Apart from a variety of digital, high quality audio channels providing news, views, education and entertainment opportunities, the end users can also get a responsive multimedia. The multimedia is being planned as a specially packaged offering that can meet the demand of students, professionals as well as certain special groups who have certain specific data and information requirements. Apart from WorldSpace, renowned agencies/firms from different parts of the world shall provide the required content to meet these requirements. Though the Internet option is available, higher telephone charges and the difficulty in getting access have made this option less

  8. Application of Multicast-based Video Conference on CERNET Backbone

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Multicast-based video conference is a representative application in advanced network. In multi-point video conference using multicast can get better efficiency facilitated by inner-group broadcast mechanism. In the application, the multicast-based network resources assignment, management and security should be considered together. This paper presents a framework model of multicast-based video conferencing application with three layers. And a practical multicast-based video conferencing is implemented in CERNET(China Education and Research Network) backbone. The practice is valuable for the development of multicast-based video conferencing application in China.

  9. CodedStream: live media streaming with overlay coded multicast

    Science.gov (United States)

    Guo, Jiang; Zhu, Ying; Li, Baochun

    2003-12-01

    Multicasting is a natural paradigm for streaming live multimedia to multiple end receivers. Since IP multicast is not widely deployed, many application-layer multicast protocols have been proposed. However, all of these schemes focus on the construction of multicast trees, where a relatively small number of links carry the multicast streaming load, while the capacity of most of the other links in the overlay network remain unused. In this paper, we propose CodedStream, a high-bandwidth live media distribution system based on end-system overlay multicast. In CodedStream, we construct a k-redundant multicast graph (a directed acyclic graph) as the multicast topology, on which network coding is applied to work around bottlenecks. Simulation results have shown that the combination of k-redundant multicast graph and network coding may indeed bring significant benefits with respect to improving the quality of live media at the end receivers.

  10. Performance Evaluation of Multicast Video Distribution using LTE-A in Vehicular Environments

    OpenAIRE

    Thota, Jayashree; Bulut, Berna; Doufexi, Angela; Armour, Simon; Nix, Andrew

    2017-01-01

    Application Layer Forward Error Correction (AL-FEC) based on Raptor codes has been employed in Multimedia Broadcast/Multicast Services (MBMS) to improve reliability. This paper considers a cross-layer system based on the latest Raptor Q codes for transmitting high data rate video. Multiple Input Multiple Output (MIMO) channels in a realistic outdoor environment for a user moving at 50kmph in an LTE-A system is considered. A link adaptation model with optimized cross-layer parameters is propos...

  11. Multicasting in a WDM-upgraded Resilient Packet Ring

    Science.gov (United States)

    Scheutzow, Michael; Seeling, Patrick; Maier, Martin; Reisslein, Martin

    2007-05-01

    The recently approved IEEE 802.17 Resilient Packet Ring (RPR) network deteriorates under multicast traffic to legacy ring technologies that do not support spatial reuse. We extend our multicast approach with spatial reuse from a currently single-channel RPR to WDM-upgraded multichannel RPR networks, where each node can transmit packets on all wavelengths and receive on one wavelength, and analyze their multicast capacity. Our analysis provides a convenient method for evaluating the multicast and reception capacities of WDM-upgraded RPR networks for a wide range of uniform unicast, multicast, and broadcast traffic scenarios.

  12. Apache cluster in multimedia broadcast content management platform%Apache集群在多媒体内容播控管理平台上的应用*

    Institute of Scientific and Technical Information of China (English)

    张小锋; 朱晓民

    2013-01-01

    随着终端用户的增加,多媒体内容播控管理平台对高访问量、高并发的需求越来越高。本文首先介绍了Apache集群的原理,然后将其应用于多媒体内容播控管理平台中,通过均衡负载,减轻了服务器的负担,提高了响应速度。%With the increasing of the end users, the multimedia broadcast content management platform requires web service with higher speed and better performance. This paper ifrst introduces the principle of the Apache cluster, and then uses the techenique in multimedia broadcast content management platform. Through balancing the load of web servers, it can reduce the burden of server and improve the response speed.

  13. A Heuristic Algorithm for Core Selection in Multicast Routing

    Institute of Scientific and Technical Information of China (English)

    Manas Ranjan Kabat; Manoj Kumar Patel; Chita Ranjan Tripathy

    2011-01-01

    With the development of network multimedia technology,more and more real-time multimedia applications need to transmit information using multicast.The basis of multicast data transmission is to construct a multicast tree.The main problem concerning the construction of a shared multicast tree is selection of a root of the shared tree or the core point.In this paper,we propose a heuristic algorithm for core selection in multicast routing.The proposed algorithm selects core point by considering both delay and inter-destination delay variation.The simulation results show that the proposed algorithm performs better than the existing algorithms in terms of delay variation subject to the end-to-end delay bound.The mathematical time complexity and the execution time of the proposed algorithm are comparable to those of the existing algorithms.

  14. Next generation mobile broadcasting

    CERN Document Server

    Gómez-Barquero, David

    2013-01-01

    Next Generation Mobile Broadcasting provides an overview of the past, present, and future of mobile multimedia broadcasting. The first part of the book-Mobile Broadcasting Worldwide-summarizes next-generation mobile broadcasting technologies currently available. This part covers the evolutions of the Japanese mobile broadcasting standard ISDB-T One-Seg, ISDB-Tmm and ISDB-TSB; the evolution of the South Korean T-DMB mobile broadcasting technology AT-DMB; the American mobile broadcasting standard ATSC-M/H; the Chinese broadcasting technologies DTMB and CMMB; second-generation digital terrestrial

  15. Reliable multicasting in the Xpress Transport Protocol

    Energy Technology Data Exchange (ETDEWEB)

    Atwood, J.W. [Concordia Univ., Montreal, PQ (Canada); Catrina, O. [Polytehnica Univ., Bucharest (Romania); Fenton, J. [Mentat, Inc., Los Angeles, CA (United States); Strayer, W.T. [Sandia National Labs., Livermore, CA (United States)

    1996-12-01

    The Xpress Transport Protocol (XTP) is designed to meet the needs of distributed, real-time, and multimedia systems. This paper describes the genesis of recent improvements to XTP that provide mechanisms for reliable management of multicast groups, and gives details of the mechanisms used.

  16. Enhanced power saving mechanism for supporting multicast services in 802.11 wireless LANs

    Institute of Scientific and Technical Information of China (English)

    Yong HE; Rui-xi YUAN; Xiao-jun MA; Jun LI

    2009-01-01

    Traditional 802. 11 power saving mechanism (PSM) treats multicast and broadcast traffic equally, and suffers significant performance degradation with multicast background traffic. This paper proposes an enhanced PSM that effectively differentiates multicast streams. It re-arranges the virtual bitmap of the traffic indication map (TIM) to carry traffic status for multicast groups and introduces a concept of sequential transmission of multi-addressed data to facilitate differentiation among multicast groups. Our analysis shows that the enhanced PSM can effectively save power in mixed traffic environments.

  17. Cross-Layer Optimal Rate Allocation for Heterogeneous Wireless Multicast

    Directory of Open Access Journals (Sweden)

    Amr Mohamed

    2009-01-01

    Full Text Available Heterogeneous multicast is an efficient communication scheme especially for multimedia applications running over multihop networks. The term heterogeneous refers to the phenomenon when multicast receivers in the same session require service at different rates commensurate with their capabilities. In this paper, we address the problem of resource allocation for a set of heterogeneous multicast sessions over multihop wireless networks. We propose an iterative algorithm that achieves the optimal rates for a set of heterogeneous multicast sessions such that the aggregate utility for all sessions is maximized. We present the formulation of the multicast resource allocation problem as a nonlinear optimization model and highlight the cross-layer framework that can solve this problem in a distributed ad hoc network environment with asynchronous computations. Our simulations show that the algorithm achieves optimal resource utilization, guarantees fairness among multicast sessions, provides flexibility in allocating rates over different parts of the multicast sessions, and adapts to changing conditions such as dynamic channel capacity and node mobility. Our results show that the proposed algorithm not only provides flexibility in allocating resources across multicast sessions, but also increases the aggregate system utility and improves the overall system throughput by almost 30% compared to homogeneous multicast.

  18. Data broadcasting: merging digital broadcasting with the Internet

    DEFF Research Database (Denmark)

    2001-01-01

    resulting from dense traffic on the Internet * Considers the technical implications of data broadcasting over different network infrastructures * Examines the process of developing and launching multimedia channels in a data broadcasting environment. Essential, up to date coverage for executives...

  19. Delay-Constrained Multicast Routing Algorithm Based on Average Distance Heuristic

    CERN Document Server

    Ling, Zhou; Yu-xi, Zhu; 10.5121/ijcnc.2010.2212

    2010-01-01

    Multicast is the ability of a communication network to accept a single message from an application and to deliver copies of the message to multiple recipients at different location. With the development of Internet, Multicast is widely applied in all kinds of multimedia real-time application: distributed multimedia systems, collaborative computing, video-conferencing, distance education, etc. In order to construct a delay-constrained multicast routing tree, average distance heuristic (ADH) algorithm is analyzed firstly. Then a delay-constrained algorithm called DCADH (delay-constrained average distance heuristic) is presented. By using ADH a least cost multicast routing tree can be constructed; if the path delay can't meet the delay upper bound, a shortest delay path which is computed by Dijkstra algorithm will be merged into the existing multicast routing tree to meet the delay upper bound. Simulation experiments show that DCADH has a good performance in achieving a low-cost multicast routing tree.

  20. QOS-BASED MULTICAST ROUTING OPTIMIZATION ALGORITHMS FOR INTERNET

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Most of the multimedia applications require strict Quality-of-Service (QoS) guarantee during the communication between a single source and multiple destinations. The paper mainly presents a QoS Multicast Routing algorithms based on Genetic Algorithm (QMRGA). Simulation results demonstrate that the algorithm is capable of discovering a set of QoS-based near optimized, non-dominated multicast routes within a few iterations, even for the networks environment with uncertain parameters.

  1. Using IGMP V3 for controllable multicast over EPON

    Science.gov (United States)

    Zhang, Chuanhao; Liu, Deming; Zhang, Li; Wu, Guangsheng

    2008-11-01

    The character of 1Gbps bandwidth and tree-based structure make EPON very suitable for broadcast or multicast services such as IPTV. The document proposed a novel scheme, based on the former research for controllable multicast over EPON system, mainly considering system security and maintainability. It can both control the IPTV program source's and the receiver's validity, improving the efficiency and precision. The processing of the two configurations mode is given in detail.

  2. New multicast authentication protocol for entrusted members using advanced encryption standard

    Directory of Open Access Journals (Sweden)

    Reham Abdellatif Abouhogail

    2011-12-01

    Full Text Available Today there is a widening in digital technologies and increasing in new multimedia services like: pay-per-view TV, interactive simulations, teleconferencing. So there is an increasing demand for multicast communication. There is a number of security issues in multicast communication directly related to the specific nature of multicast. In this paper, we propose a new scheme for authenticating streamed data delivered in real-time over an insecure network, and we concentrate on the multicast authentication problem. Important requirements of multicast communication protocols are: to perform authentication in real-time, to resist packet loss and to have low communication and computation overheads. In this paper, a new multicast authentication scheme is proposed. It is suitable for real time applications. It uses the advanced encryption standard algorithm to solve the problem of entrusted members. This scheme uses the idea of the new index number each time the member sends certain block of packets in the multicast group.

  3. Multimedia

    Institute of Scientific and Technical Information of China (English)

    Andrew; Scales; 张少林

    1997-01-01

    Imagine a world where your TV, telephone and computer areall one system. You have a central central box connected to thetelephone line and several screens in different rooms around yourhome or office. You can speak to these screens and call up whateverservices you like-services such as movies, videophone, homeshopping, telebanking, interactive video games and English lessons. This is the world of multimedia, a world where books, text,

  4. Multimedia

    Directory of Open Access Journals (Sweden)

    Eva Milková

    2015-01-01

    Full Text Available This paper is based on many years’ experience with multimedia applications supporting the area of computer science education and it could serve as an inspirational material directed to all educators developing students’ algorithmic thinking. Education of subjects related with computer science is from the perspective of other for centuries taught subjects, still in its infancy. Even nowadays a teaching method aimed at developing algorithmic thinking of students is still the subject of extensive discussions and teachers are looking for different ways on how to access it to students. Next to the educational approach to this base of computer science it is also important to find a suitable support for students’ self-learning. Multimedia applications give teachers an excellent chance to demonstrate and visualize the subject matter more clearly and comprehensibly, as well as also enabling them to prepare study material for students which optimizes their study habits. Along with large software products developed by a team of professionals there are also various smaller programs dealing with objects appropriate to course subject matter created on a script given by the teacher with regard to students’ needs. In the paper such application prepared to intensify self-preparation of students in subjects developing algorithmic thinking is introduced and its benefit discussed. Animations useful to be used as an introductory complement to lectures are introduced as well. At the end advantages of the professional virtual learning environment containing such study material are mentioned.

  5. Distributed QoS multicast routing protocol in ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    Sun Baolin; Li Layuan

    2006-01-01

    Quality of service (QoS) routing and multicasting protocols in ad hoc networks are face with the challenge of delivering data to destinations through multihop routes in the presence of node movements and topology changes. The multicast routing problem with multiple QoS constraints is discussed, which may deal with the delay, bandwidth and cost metrics, and describes a network model for researching the ad hoc networks QoS multicast routing problem. It presents a distributed QoS multicast routing protocol (DQMRP). The proof of correctness and complexity analysis of the DQMRP are also given. Simulation results show that the multicast tree optimized by DQMRP is better than other protocols and is fitter for the network situations with frequently changed status and the real-time multimedia application. It is an available approach to multicast routing decision with ultiple QoS constraints.

  6. A Primer of Multicast Routing

    CERN Document Server

    Rosenberg, Eric

    2012-01-01

    Whereas unicast routing determines a path from one source node to one destination node, multicast routing determines a path from one source to many destinations, or from many sources to many destinations. We survey multicast routing methods for when the set of destinations is static, and for when it is dynamic. While most of the methods we review are tree based, some non-tree methods are also discussed. We survey results on the shape of multicast trees, delay constrained multicast routing, aggregation of multicast traffic, inter-domain multicast, and multicast virtual private networks. We focu

  7. QoS Routing in Multicast Networks Based on Imperialism Competition Algorithm

    Directory of Open Access Journals (Sweden)

    Parisa Mollamohammada

    Full Text Available At the age of multimedia communications and high speed networks, multicast is one of the mechanisms which we can employ to enjoy the power of internet. On the other hand, increase in real-time multimedia applications, has emerged the need for Quality of S ...

  8. Topology-aware Overlay Multicast over IP Multicast Networks

    Institute of Scientific and Technical Information of China (English)

    CHEN Xiao; SHAO Hua-gang; WANG Wei-nong

    2008-01-01

    Most existing overlay multicast approaches refuse to consider any network layer support no matter whether it is available or not. This design principle greatly increases the complexity of the routing algorithms and makes the overlay topologies incompatible with the underlying network. To address these issues, topology-aware overlay multicast over IP multicast networks (TOMIMN) was proposed as a novel overlay multicast protocol, which exploits the cooperation between end-hosts and IP multicast routers to construct a topology-aware overlay tree. Through a little modification to protocol independent multicast sparse mode (PIM-SM),a multicast router is able to receive registration from nearby group members and redirect passing-by join re-quests to them. Due to the multicast router's support, TOMIMN organizes its group members into an overlay multicast tree efficiently, which matches the physical network topology well.

  9. UNICAST FORWARDED MULTI-SOURCE MULTICAST ROUTING PROTOCOL FOR MANET

    Directory of Open Access Journals (Sweden)

    J. Rangarajan

    2013-03-01

    Full Text Available In mobile ad hoc network, nodes co-operatively form a network independent of any fixed base station infrastructure. Every node in a mobile ad-hoc network can function as a router and forwards the data packets to the other nodes. Multicasting plays an important role whenever group communications are required. Most of the existing multicast routing protocols in mobile ad hoc networks consider only one source in a multicast group and become inefficient when the protocol is extended to multi-source multicasting. In this paper, we propose a unicast forwarded multi-source multicast routing protocol, for ad hoc networks which is having more than one source in a group. Here, the sources of the group also act as a receiver for other sources in that group. The proposed routing method is a cluster based one and avoids the flooding or broadcasting of control packets to form routing structure. On executing source joining and receiver joining procedures, a complete path for multicast data transfer was established. As the join request control packets are forwarded only through cluster-heads and junction nodes, lower amount of control overhead is incurred. Simulation result shows that the proposed protocol maintains the delivery ratio with reduced control overhead and utilizes the bandwidth efficiently.

  10. Netrawalm: Network Based Resource Aware Application Layer Multicast for Multiparty Video Conference

    CERN Document Server

    Ruso, T

    2011-01-01

    IP Multicast is one of the most absolute method for large bandwidth Internet applications such as video conference, IPTV, E-Learning and Telemedicine etc., But due to security and management reason IP Multicast is not enabled in Internet backbone routers. To achieve these challenges, lot of Application Layer Multicast (ALM) has been proposed. All the existing protocols such as NICE, ZIGZAG and OMNI are trying to reduce average delay by forming a Multicast tree. But still that problem has not been addressed fully. We are proposing a new protocol called NetRawALM, which will address the average delay, Reliability between nodes, Scalability of conference, Heterogeneity and resilient data distribution for real time multimedia applications by constructing the Network based Resource aware Multicast tree algorithm. This is very dynamic and decentralised. The proposed architecture is a LAN aware; it is used to reduce Internet Traffic.

  11. Multicast routing with bandwidth and delay constraints based on genetic algorithms

    Directory of Open Access Journals (Sweden)

    Ahmed Younes

    2011-07-01

    Full Text Available Many multimedia communication applications require a source to send multimedia information to multiple destinations through a communication network. To support these applications, it is necessary to determine a multicast tree of minimal cost to connect the source node to the destination nodes subject to delay constraints on multimedia communication. This problem is known as multimedia multicast routing and has been proved to be NP-complete. The paper proposes a genetic algorithm for solving multimedia multicast routing, which find the low-cost multicasting tree with bandwidth and delay constraints. In the proposed algorithm, the k shortest paths from the source node to the destination nodes are used for genotype representation. The simulation results show that the proposed algorithm is able to find a better solution, fast convergence speed and high reliability. It can meet the real-time requirement in multimedia communication networks. The scalability and the performance of the algorithm with increasing number of network nodes are also quite encouraged.

  12. Experimental Evaluation of a Scalable WiFi Multicast Scheme in the ORBIT Testbed

    OpenAIRE

    Bejerano, Yigal; Ferragut, Jaime; Guo, Katherine; Gupta, Varun; Gutterman, Craig; Nandagopal, Thyaga; Zussman, Gil

    2014-01-01

    IEEE 802.11-based wireless local area networks, referred to as WiFi, have been globally deployed and the vast majority of the mobile devices are currently WiFi-enabled. While WiFi has been proposed for multimedia content distribution, its lack of adequate support for multicast services hinders its ability to provide multimedia content distribution to a large number of devices. In earlier work, we proposed a dynamic scheme called AMuSe that selects a subset of the multicast receivers as feedba...

  13. An Intelligent Multicast Ad-hoc On demand Distance Vector Protocol for MANETs

    Directory of Open Access Journals (Sweden)

    E. Baburaj

    2008-06-01

    Full Text Available Recently multicast ro uting protocols in Mobile Ad-hoc Networks (MANETs are emerging for wireless group communication. This includes application such as multipoint data dissemination and multiparty conferencing which made the analytical design and development of the MANETs in a very efficient manner. For MANETs there are several multicast routing protocols are available, but they perform well under specific scenarios only. The topology of a MANET changes adequately based on the random mobility of network nodes, unlike the network topology of a wired network which is static.Multicast routing protocol outperforms the basic broadcast routing by sharing the resources along general links, while sending information to a set of predefined multiple destinations in a concurrent way. Due to the lack of redundancy in multipath and multicast structures, the multicast routing protocols are vulnerable to the component failure in ad-hoc networks. So it is the dire need to solve the problem optimally. One of the efficient techniques for solving the optimization problem is the Genetic Algorithm (GA. The key factors that determine the performance of GA is by the well designed architecture of chromosomes and operators in the intelligent algorithm. This paper proposes a new genetic algorithm based Multicast Ad-hoc On demand Distance Vector Protocol for MANETs (GA-MAODV, which improves the packet delivery ratio of the routing messages. The GAbased MAODV allows each node in the network to send out multicast data packets, and the multicast data packets are broadcast when propagating along the multicast group tree.

  14. Analytical modeling of bargaining solutions for multicast cellular services

    Directory of Open Access Journals (Sweden)

    Giuseppe Araniti

    2013-07-01

    Full Text Available Nowadays, the growing demand for group-oriented services over mobile devices has lead to the definition of new communication standards and multimedia applications in cellular systems. In this article we study the use of game theoretic solutions for these services to model and perform a trade-off analysis between fairness and efficiency in the resources allocation. More precisely, we model bargaining solutions for the multicast data services provisioning and introduce the analytical resolution for the proposed solutions.

  15. Multicast and IP Multicast Support in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jorge Sá Silva

    2008-03-01

    Full Text Available Multicast potentially optimises bandwidth consumption and node resources, when several users simultaneously participate in a communication session. Nevertheless, contrary to the expectations, IP multicast has not experienced widespread deployment, with the exception of IPTV. On the other hand, emerging Wireless Sensor Network (WSN applications could greatly benefit from multicast and constitute another field where multicast can be an effective and efficient technique. The questions are: do multicast advantages hold in WSN scenarios? Can we use IP Multicast functionality in WSNs? This paper discusses and evaluates the use of multicast in WSNs. Specifically, we evaluate the use of Source-Specific Multicast, as it is one of the most promising paradigms for IP networking, considering both IPv4 and IPv6 in WSNs. A sensor platform with IP and multicast support that is being developed in our lab is presented. Concurrently, simulation studies were performed in order to assess the usefulness of multicast in WSNs. The results clearly point to the benefits of the use of this technique in processing and energy-restricted environments such as this one.

  16. SUPPORTING MPLS VPN MULTICAST

    Institute of Scientific and Technical Information of China (English)

    Wang Yufeng; Wang Wendong; Cheng Shiduan

    2004-01-01

    MPLS(Multi-Protocol Label Switching) VPN(Virtual Private Network) traffic has been deployed widely, but currently only supports unicast. This paper briefly introduces several available MPLS VPN multicast approaches, and then analyzes their disadvantages. A novel mechanism that uses two-layer label stack to support MPLS VPN explicit multicast is proposed and the process is discussed in detail. The scalability and performance of the proposed mechanism are studied analytically. The result shows that our solution has great advantage over the currently available scheme in terms of saving core network bandwidth and improving the scalability.

  17. Multicast Capacity Scaling of Wireless Networks with Multicast Outage

    CERN Document Server

    Liu, Chun-Hung

    2010-01-01

    Multicast transmission has several distinctive traits as opposed to more commonly studied unicast networks. Specially, these include (i) identical packets must be delivered successfully to several nodes, (ii) outage could simultaneously happen at different receivers, and (iii) the multicast rate is dominated by the receiver with the weakest link in order to minimize outage and retransmission. To capture these key traits, we utilize a Poisson cluster process consisting of a distinct Poisson point process (PPP) for the transmitters and receivers, and then define the multicast transmission capacity (MTC) as the maximum achievable multicast rate times the number of multicast clusters per unit volume, accounting for outages and retransmissions. Our main result shows that if $\\tau$ transmission attempts are allowed in a multicast cluster, the MTC is $\\Theta\\left(\\rho k^{x}\\log(k)\\right)$ where $\\rho$ and $x$ are functions of $\\tau$ depending on the network size and density, and $k$ is the average number of the inte...

  18. Data broadcasting: merging digital broadcasting with the Internet

    DEFF Research Database (Denmark)

    2001-01-01

    This fully revised and updated edition of Data Broadcasting presents an exhaustive overview of the specific data broadcasting and bordering technologies concerned. Answering a wealth of questions, it describes this new technology in detail, examining how it differs from established technologies......, and for what means it can be used. It also analyses data broadcasting from the perspectives of both the medium and business. * Features the latest developments in electronic media * Discusses the major media opportunities of data broadcasting * Shows how data broadcasting can overcome many notorious problems...... resulting from dense traffic on the Internet * Considers the technical implications of data broadcasting over different network infrastructures * Examines the process of developing and launching multimedia channels in a data broadcasting environment. Essential, up to date coverage for executives...

  19. NETRAWALM: NETWORK BASED RESOURCE AWARE APPLICATION LAYER MULTICAST FOR MULTIPARTY VIDEO CONFERENCE

    Directory of Open Access Journals (Sweden)

    T. Ruso

    2011-10-01

    Full Text Available IP Multicast is one of the most absolute method for large bandwidth Internet applications such as videoconference, IPTV, E-Learning and Telemedicine etc., But due to security and management reason IPMulticast is not enabled in Internet backbone routers. To achieve these challenges, lot of ApplicationLayer Multicast (ALM has been proposed. All the existing protocols such as NICE, ZIGZAG and OMNIare trying to reduce average delay by forming a Multicast tree. But still that problem has not beenaddressed fully. We are proposing a new protocol called NetRawALM, which will address the averagedelay, Reliability between nodes, Scalability of conference, Heterogeneity and resilient data distributionfor real time multimedia applications by constructing the Network based Resource aware Multicast treealgorithm. This is very dynamic and decentralised. The proposed architecture is a LAN aware; it is usedto reduce Internet Traffic.

  20. QoS-aware multicast routing protocol for Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    Sun Baolin; Li Layuan

    2006-01-01

    Ad hoc wireless networks consist of mobile nodes interconnected by multihop communication paths. Unlike conventional wireless networks, ad hoc networks have no fixed network infrastructure or administrative support. Due to bandwidth constraint and dynamic topology of mobile ad hoc networks, supporting Quality of Service (QoS) is an inherently complex, difficult issue and very important research issue. MAODV (Multicast Ad hoc Ondemand Distance Vector) routing protocol provides fast and efficient route establishment between mobile nodes that need to communicate with each other. MAODV has minimal control overhead and route acquisition latency. In addition to unicast routing, MAODV supports multicast and broadcast as well.The multicast routing problem with multiple QoS constraints, which may deal with the delay, bandwidth and packet loss measurements is discussed, and a network model for researching the ad hoc network QoS multicast routing problem is described. It presents a complete solution for QoS multicast routing based on an extension of the MAODV routing protocol that deals with delay, bandwidth and packet loss measurements. The solution is based on lower layer specifics. Simulation results show that, with the proposed QoS multicast routing protocol, end-to-end delay, bandwidth and packet loss on a route can be improved in most of cases. It is an available approach to multicast routing decision with multiple QoS constraints.

  1. A Multicast Routing Algorithm for Datagram Service in Delta LEO Satellite Constellation Networks

    Directory of Open Access Journals (Sweden)

    Yanpeng Ma

    2014-04-01

    Full Text Available Satellites can broadcast datagram over wide areas, therefore, the satellite network has congenital advantages to implement multicast service. LEO satellite has the property of efficient bandwidth usage, lower propagation delay and lower power consumption in the user terminals and satellites. Therefore, the constellation network composed by LEO satellites is an essential part of future satellite communication networks. In this paper, we propose a virtual center based multicast (VCMulticast routing algorithm for LEO satellite constellation network. The algorithm uses the geographic center information of group users to route multicast datagrams, with less memory, computer power and signaling overhead. We evaluate the delay and performance of our algorithm by means of simulations in the OPENET simulator. The results indicate that the delay of the proposed multicast method exceeds the minimum propagation by at most 29.1% on the average, which is a quite acceptable achievement, considering the resource overhead reduction that can be introduced by our proposal

  2. RMAC: A Reliable MAC Protocol Supporting Multicast for Wireless Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    Wei-Sheng Si; Cheng-Zhi Li

    2005-01-01

    This paper presents a new reliable MAC protocol called "RMAC" supporting reliable multicast for wireless ad hoc networks. By utilizing the busy tones to realize the multicast reliability, RMAC has three novelties: (1) it uses a variablelength control frame to stipulate an order for the receivers to respond, thus solving the feedback collision problem; (2) it extends the usage of busy tone for preventing data frame collisions into the multicast scenario; and (3) it introduces a new usage of busy tone for acknowledging data frames positively. In addition, RMAC is generalized into a comprehensive MAC protocol that provides both reliable and unreliable services for all the three modes of communications: unicast, multicast,and broadcast, making it capable of supporting various upper-layer protocols. The evaluation shows that RMAC achieves high reliability with very limited overhead. RMAC is also compared with other reliable MAC protocols, showing that RMAC not only provides higher reliability but also involves lower cost.

  3. Internet连续媒体多播技术综述%Survey of Techniques for Internet Continuous Media Multicast

    Institute of Scientific and Technical Information of China (English)

    杨明; 张福炎

    2002-01-01

    Continuous media multicast has been an important component of many networked services such as audio-visual broadcast and video conferencing.The problems of scalability,congestion control,heterogeneity and reliability,which confront Internet continuous media multicast,are presented first,and then overview of the adaptive rate control schemes and techniques to solve these problems are stated.Finally,we discuss some treds and unsolved issues in the field.

  4. Scalable Multicasting over Next-Generation Internet Design, Analysis and Applications

    CERN Document Server

    Tian, Xiaohua

    2013-01-01

    Next-generation Internet providers face high expectations, as contemporary users worldwide expect high-quality multimedia functionality in a landscape of ever-expanding network applications. This volume explores the critical research issue of turning today’s greatly enhanced hardware capacity to good use in designing a scalable multicast  protocol for supporting large-scale multimedia services. Linking new hardware to improved performance in the Internet’s next incarnation is a research hot-spot in the computer communications field.   The methodical presentation deals with the key questions in turn: from the mechanics of multicast protocols to current state-of-the-art designs, and from methods of theoretical analysis of these protocols to applying them in the ns2 network simulator, known for being hard to extend. The authors’ years of research in the field inform this thorough treatment, which covers details such as applying AOM (application-oriented multicast) protocol to IPTV provision and resolving...

  5. Design, Implementation, and Verification of the Reliable Multicast Protocol. Thesis

    Science.gov (United States)

    Montgomery, Todd L.

    1995-01-01

    This document describes the Reliable Multicast Protocol (RMP) design, first implementation, and formal verification. RMP provides a totally ordered, reliable, atomic multicast service on top of an unreliable multicast datagram service. RMP is fully and symmetrically distributed so that no site bears an undue portion of the communications load. RMP provides a wide range of guarantees, from unreliable delivery to totally ordered delivery, to K-resilient, majority resilient, and totally resilient atomic delivery. These guarantees are selectable on a per message basis. RMP provides many communication options, including virtual synchrony, a publisher/subscriber model of message delivery, a client/server model of delivery, mutually exclusive handlers for messages, and mutually exclusive locks. It has been commonly believed that total ordering of messages can only be achieved at great performance expense. RMP discounts this. The first implementation of RMP has been shown to provide high throughput performance on Local Area Networks (LAN). For two or more destinations a single LAN, RMP provides higher throughput than any other protocol that does not use multicast or broadcast technology. The design, implementation, and verification activities of RMP have occurred concurrently. This has allowed the verification to maintain a high fidelity between design model, implementation model, and the verification model. The restrictions of implementation have influenced the design earlier than in normal sequential approaches. The protocol as a whole has matured smoother by the inclusion of several different perspectives into the product development.

  6. multicast utilizando Simulated Annealing

    Directory of Open Access Journals (Sweden)

    Yezid Donoso

    2005-01-01

    Full Text Available En este artículo se presenta un método de optimización multiobjetivo para la solución del problema de balanceo de carga en redes de transmisión multicast, apoyándose en la aplicación de la meta-heurística de Simulated Annealing (Recocido Simulado. El método minimiza cuatro parámetros básicos para garantizar la calidad de servicio en transmisiones multicast: retardo origen destino, máxima utilización de enlaces, ancho de banda consumido y número de saltos. Los resultados devueltos por la heurística serán comparados con los resultados arrojados por el modelo matemático propuesto en investigaciones anteriores.

  7. SOME NOTES ON COST ALLOCATION IN MULTICASTING

    Directory of Open Access Journals (Sweden)

    Darko Skorin-Kapov

    2012-12-01

    Full Text Available We analyze the cost allocation strategies with the problef of broadcasting information from some source to a number of communication network users. A multicast routing chooses a minimum cost tree network that spans the source and all the receivers. The cost of such a network is distributed among its receivers who may be individuals or organizations with possibly conflicting interests. Providing network developers, users and owners with practical computable 'fair' cost allocation solution procedures is of great importance for network mamagement. Consequently, this multidisciplinary problem was extensively studied by Operational Researchers, Economists, Mathematicians and Computer Scientists. The fairness of various proposed solutions was even argued in US courts. This presentation overviews some previously published, as well as some recent results, in the development of algorithmic mechanisms to efficiently compute 'attractive' cost allocation solutions for multicast networks. Specifically, we will analyze cooperative game theory based cost allocation models that avoid cross subsidies and/or are distance and population monotonic. We will also present some related open cost allocation problems and the potential contribution that such models might make to this problem in the future.

  8. QoS Supported IPTV Service Architecture over Hybrid-Tree-Based Explicit Routed Multicast Network

    Directory of Open Access Journals (Sweden)

    Chih-Chao Wen

    2012-01-01

    Full Text Available With the rapid advance in multimedia streaming and multicast transport technology, current IP multicast protocols, especially PIM-SM, become the major channel delivery mechanism for IPTV system over Internet. The goals for IPTV service are to provide two-way interactive services for viewers to select popular program channel with high quality for watching during fast channel surfing period. However, existing IP multicast protocol cannot meet above QoS requirements for IPTV applications between media server and subscribers. Therefore, we propose a cooperative scheme of hybrid-tree based on explicit routed multicast, called as HT-ERM to combine the advantages of shared tree and source tree for QoS-supported IPTV service. To increase network utilization, the constrained shortest path first (CSPF routing algorithm is designed for construction of hybrid tree to deliver the high-quality video stream over watching channel and standard quality over surfing channel. Furthermore, the Resource Reservation Protocol- Traffic Engineering (RSVP-TE is used as signaling mechanism to set up QoS path for multicast channel admission control. Our simulation results demonstrated that the proposed HT-ERM scheme outperforms other multicast QoS-based delivery scheme in terms of channel switching delay, resource utilization, and blocking ratio for IPTV service.

  9. Modeling of reliable multicasting services

    DEFF Research Database (Denmark)

    Barkauskaite, Monika; Zhang, Jiang; Wessing, Henrik

    2010-01-01

    This paper addresses network survivability for Multicast transport over MPLS-TP ring topology networks. Protection mechanisms standardized for unicast are not fully suitable for multicast point-to-multipoint transmission and multicast schemes are not standardized yet. Therefore, this paper...... investigates one of the proficient protection schemes and uses OPNET Modeler for analyzing and designing networks with the chosen protection method. For failure detection and protection switching initiation, the OAM (Operation, Administration and Maintenance) functions will be added to the system model. From...

  10. An Improved Multicast Routing Algorithm

    Institute of Scientific and Technical Information of China (English)

    蒋廷耀; 李庆华

    2004-01-01

    Multicasting is a communication service that allows an application to efficiently transmit copies of data packets to a set of destination nodes. The problem of finding a minimum cost multicast tree can be formulated as a minimum Steiner tree problem in networks, which is NP-completeness. MPH (minimum path cost heuristic) algorithm is a famous solution to this problem. In this paper,we present a novel solution TPMPH (two phase minimum path cost heuristic) to improve the MPH by generating the nodes and the edges of multicast tree separately. The cost of multicast tree generated by the proposed algorithm with the same time as MPH is no more than that of MPH in the worst case. Extensive simulation results show that TPMPH can effectively improve the performance on MPH, and performs better in large-scale networks and wireless networks.

  11. Protection switching for carrier ethernet multicast

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Berger, Michael Stübert

    2010-01-01

    This paper addresses network survivability for IPTV multicast transport in Carrier Ethernet networks. The impact of link failures is investigated and suggestions for intelligent multicast resilience schemes are proposed. In particular, functions of the multicast tree are integrated with the Carrier...

  12. Bluetooth broadcasting

    OpenAIRE

    Ho, Johan

    2006-01-01

    Background: The wireless technology Bluetooth has rapidly become more commonly supported by electronic devices like mobile phones and PDAs. Several companies are currently developing Bluetooth broadcasting systems to use for marketing. This report is a result of researching the use of Bluetooth broadcasting for delivering information for more general purposes, how well Bluetooth actually works for broadcasting, and also on the topic of user privacy. Results: Broadcasting with Bluetooth did w...

  13. A Secure Network Coding Based on Broadcast Encryption in SDN

    Directory of Open Access Journals (Sweden)

    Yue Chen

    2016-01-01

    Full Text Available By allowing intermediate nodes to encode the received packets before sending them out, network coding improves the capacity and robustness of multicast applications. But it is vulnerable to the pollution attacks. Some signature schemes were proposed to thwart such attacks, but most of them need to be homomorphic that the keys cannot be generated and managed easily. In this paper, we propose a novel fast and secure switch network coding multicast (SSNC on the software defined networks (SDN. In our scheme, the complicated secure multicast management was separated from the fast data transmission based on the SDN. Multiple multicasts will be aggregated to one multicast group according to the requirements of services and the network status. Then, the controller will route aggregated multicast group with network coding; only the trusted switch will be allowed to join the network coding by using broadcast encryption. The proposed scheme can use the traditional cryptography without homomorphy, which greatly reduces the complexity of the computation and improves the efficiency of transmission.

  14. Many-to-Many Multicast Routing Schemes under a Fixed Topology

    Directory of Open Access Journals (Sweden)

    Wei Ding

    2013-01-01

    Full Text Available Many-to-many multicast routing can be extensively applied in computer or communication networks supporting various continuous multimedia applications. The paper focuses on the case where all users share a common communication channel while each user is both a sender and a receiver of messages in multicasting as well as an end user. In this case, the multicast tree appears as a terminal Steiner tree (TeST. The problem of finding a TeST with a quality-of-service (QoS optimization is frequently NP-hard. However, we discover that it is a good idea to find a many-to-many multicast tree with QoS optimization under a fixed topology. In this paper, we are concerned with three kinds of QoS optimization objectives of multicast tree, that is, the minimum cost, minimum diameter, and maximum reliability. All of three optimization problems are distributed into two types, the centralized and decentralized version. This paper uses the dynamic programming method to devise an exact algorithm, respectively, for the centralized and decentralized versions of each optimization problem.

  15. A Rough Penalty Genetic Algorithm for Multicast Routing in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Chih-Hao Lin

    2013-01-01

    Full Text Available Multicast routing is an effective way to transmit messages to multiple hosts in a network. However, it is vulnerable to intermittent connectivity property in mobile ad hoc network (MANET especially for multimedia applications, which have some quality of service (QoS requirements. The goal of QoS provisioning is to well organize network resources to satisfy the QoS requirement and achieve good network delivery services. However, there remains a challenge to provide QoS solutions and maintain end-to-end QoS with user mobility. In this paper, a novel penalty adjustment method based on the rough set theory is proposed to deal with path-delay constraints for multicast routing problems in MANETs. We formulate the problem as a constrained optimization problem, where the objective function is to minimize the total cost of the multicast tree subject to QoS constraints. The RPGA is evaluated on three multicast scenarios and compared with two state-of-the-art methods in terms of cost, success rate, and time complexity. The performance analyses show that this approach is a self-adaptive method for penalty adjustment. Remarkably, the method can address a variety of constrained multicast routing problems even though the initial routes do not satisfy all QoS requirements.

  16. Digital audio and video broadcasting by satellite

    Science.gov (United States)

    Yoshino, Takehiko

    In parallel with the progress of the practical use of satellite broadcasting and Hi-Vision or high-definition television technologies, research activities are also in progress to replace the conventional analog broadcasting services with a digital version. What we call 'digitalization' is not a mere technical matter but an important subject which will help promote multichannel or multimedia applications and, accordingly, can change the old concept of mass media, such as television or radio. NHK Science and Technical Research Laboratories has promoted studies of digital bandwidth compression, transmission, and application techniques. The following topics are covered: the trend of digital broadcasting; features of Integrated Services Digital Broadcasting (ISDB); compression encoding and transmission; transmission bit rate in 12 GHz band; number of digital TV transmission channels; multichannel pulse code modulation (PCM) audio broadcasting system via communication satellite; digital Hi-Vision broadcasting; and development of digital audio broadcasting (DAB) for mobile reception in Japan.

  17. Using MPEG- at the Consumer Terminal in Broadcasting

    Directory of Open Access Journals (Sweden)

    Lalmas Mounia

    2002-01-01

    Full Text Available The European Union IST research programme SAMBITS (System for Advanced Multimedia Broadcast and IT Services project is using Digital Video Broadcasting (DVB, the DVB Multimedia Home Platform (MHP standard, MPEG- and MPEG- in a studio production and multimedia terminal system to integrate broadcast data and Internet data. This involves using data delivery over multiple paths and the use of a back channel for interaction. MPEG- is being used to identify programme content and to construct queries to allow users to identify and retrieve interesting related content. Searching for content is being carried out using the HySpirit search engine. The paper deals with terminal design issues, the use of MPEG- for broadcasting applications and using a consumer broadcasting terminal for searching for material related to a broadcast.

  18. System for Multicast File Transfer

    Directory of Open Access Journals (Sweden)

    Dorin Custura

    2012-03-01

    Full Text Available The distribution of big files over the network from a single source to a large number of recipients is not efficient by using standard client-server or even peer-to peer file transfer protocols.  Thus, the transfer of a hierarchy of big files to multiple destinations can be optimized in terms of bandwidth usage and data storage reads by using multicast networking. In order to achieve that, a simple application layer protocol can be imagined. It uses multicast UDP as transport and it provides a mechanism for data ordering and retransmission. Some security problems are also considered in this protocol, because at this time the Internet standards supporting multicast security are still in the development stage.

  19. Evaluación de mecanismos de soporte de tráfico multicast con movilidad basada en red

    OpenAIRE

    González Díaz, Sergio

    2015-01-01

    Con el auge actual de Internet y el incremento en el uso de dispositivos móviles ha aumentado el consumo de contenido multimedia, del cual cabe destacar el streaming de vídeo, el vídeo bajo demanda y la IPTV. Muchos de estos servicios hacen uso de Multicast, un método de transmisión de datos a múltiples redes y destinatarios de manera simultánea. Para poder realizar transmisiones de datos multicast hay direcciones IP reservadas, tanto en IPv4 como en IPv6. El funcionamiento de ...

  20. Proposing an Optimum Multicasting Routing Algorithm Using Ant Colony for Improving QoS in Wireless Mesh Network

    Directory of Open Access Journals (Sweden)

    Mohsen Shakibafakhr

    2013-11-01

    Full Text Available Wireless mesh networks (WMNs are new emerging networks which are anticipated to resolve many limitations of ad-hoc networks, sensor networks and wireless local area networks and improve their performance. But still there are many unresolved research challenge in this area. In this paper we have proposed source-specific multicast protocol for wireless mesh network, which has many application in, multimedia, radio and TV multicasting and distance learning. We have used core-based approach to construct minimum cost tree (MCT among member nodes and optimized this tree for multiple metrics by applying ant colony optimization metaphor.

  1. Network Coding in a Multicast Switch

    CERN Document Server

    Kim, MinJi; Medard, Muriel; Eryilmaz, Atilla; Koetter, Ralf

    2008-01-01

    The problem of serving multicast flows in a crossbar switch is considered. Intra-flow linear network coding is shown to achieve a larger rate region than the case without coding. A traffic pattern is presented which is achievable with coding but requires a switch speedup when coding is not allowed. The rate region with coding can be characterized in a simple graph-theoretic manner, in terms of the stable set polytope of the "enhanced conflict graph". No such graph-theoretic characterization is known for the case of fanout splitting without coding. The minimum speedup needed to achieve 100% throughput with coding is shown to be upper bounded by the imperfection ratio of the enhanced conflict graph. When applied to KxN switches with unicasts and broadcasts only, this gives a bound of min{(2K-1)/K,2N/(N+1)} on the speedup. This shows that speedup, which is usually implemented in hardware, can often be substituted by network coding, which can be done in software. Computing an offline schedule (using prior knowled...

  2. Multicast Routing in Satellite Network

    Institute of Scientific and Technical Information of China (English)

    郭惠玲; 宋姝; 李磊; 刘志涛; 郭鹏程

    2004-01-01

    There are some problems in the dual-layer satellite MPLs metworks to be composed of LEO and MEO. In order to solve the problems, this paper presents a plan by means of unicast LSP to implement multicast in the dual-layer satellite MPLs networks. It has advantages of saving space and reducing extra charge.

  3. Broadcasting house

    DEFF Research Database (Denmark)

    Sattrup, Peter Andreas

    2008-01-01

    Regarding the transformation of the Danish Broadcasting Hq. (1934-1945) in Frederiksberg by Vilhelm Lauritzen into the Royal Danish Academy of Music. Analysis, principles, flexibility and change.......Regarding the transformation of the Danish Broadcasting Hq. (1934-1945) in Frederiksberg by Vilhelm Lauritzen into the Royal Danish Academy of Music. Analysis, principles, flexibility and change....

  4. Application Layer Multicast Technology of Streaming Media

    Directory of Open Access Journals (Sweden)

    Jiansheng Liu

    2011-08-01

    Full Text Available With the rapid development of network technology, Internet business has been transferred from a simple text into a host text, audio, video and other streaming services. Application layer multicast is one of the key technologies to protect the large-scale service quality of streaming media system, which has become an important part of study. Based on the application layer multicast technology, it focused on analyzing the effects of application layer multicast to the  large-scale of media streaming system, and summarized the typical characteristics of the system. It takes efficiency of multicast robustness, scalability, and the continuity as evaluation indexes, and summarized the typical multicast. In the end,the drawbacks and develop directions of application layer multicast were discussed.

  5. IP MULTICAST GROUP MANAGEMENT FOR BROADCAST LANS DISTRIBUTION

    Institute of Scientific and Technical Information of China (English)

    Amjad; M.T.; Said(

    2001-01-01

    [1]Milner R, Parrow J, Walker D. A calculus of mobile processes[J]. Information and computation, 1992,100:1~77.[2]Milner R. Communication and Concurrency[M]. [s.l.]: Prentice Hall, 1989.[3]Pierce B, Sangiorgi D. Typing and subtyping for mobile processes[J]. Journal of Mathematical Structures in Computer Science, 1996,6(5):409~453.[4]Dam M. On the decidability of process equivalence for the π-calculus[J]. Theoretical Computer Science,1997,163:214~228.[5]Montanari U, Pistore M. Checking bismilarity for finitary π-calculus[A]. CONCUR'95[C]. Lecture Notes in Computer Science 962, Springer, 1995.42~56.[6]Victor B, Moller F. The mobility workbench--A tool for the π-calculus[A]. CAV'94[C]. Lecture Notes in Comuter Science 8188, Springer,1994.428~440.[7]李舟军.传值CCS和π-演算中互模拟等价的验证理论与算法[D].长沙:国防科技大学,1999.[8]Lin H. Symbolic transition graph with assignment[A]. CONCUR'96 [C], Lecture Notes in Computer Science 1119,Springer, 1996.50~65.[9]Boreale M, De Nicola R. A symbolic semantis for the π-calculus[J]. Information and Computation, 1996,126:34~52.[10]Pugh W, Bultan T, Gerber R. Symbolic model checking of infinite state systems using Presberger arithmetic [A].CAV'97[C]. Lecture Notes in Computer Science 1254, Springer, 1997.[11]Wolper P, Boigelot B. An automata-theoretic approach to Presburger arithmetic constraints[A]. Proceedings of Static Analysis Symposium[C]. Lecture in Computer Science 983, Springer, 1995.21~32.

  6. QoS and QoE Aware N-Screen Multicast Service

    Directory of Open Access Journals (Sweden)

    Ghulam Sarwar

    2016-01-01

    Full Text Available The paper focuses on ensuring the quality-of-service (QoS and quality-of-experience (QoE requirements of users having heterogeneous devices in a multicast session. QoS parameters such as bit rate, delays, and packet losses are good indicators for optimizing network services but fall short in characterizing user perception (QoE. In N-Screen service, the users have different devices with heterogeneous attributes like screen size, resolution, and access network interface, and the users have different QoE on N-Screen devices with the same QoS parameters. We formulate the objective function of the N-Screen multicast grouping to ensure the minimum user’s QoE with smaller bandwidth requirement. We propose a dynamic user reassignment scheme to maintain and satisfy the QoE by adapting the user’s membership to the varying network conditions. The proposed schemes combine the available bandwidth and multimedia visual quality to ensure the QoS and QoE. In the network architecture, we introduce the functions of the QoS and QoE aware multicast group management and the estimation schemes for the QoS and QoE parameters. The simulation results show that the proposed multicast service ensures the network QoS and guarantees the QoE of users in the varying network conditions.

  7. End to End Delay Improvement in Heterogeneous Multicast Network using Genetic Optimization

    Directory of Open Access Journals (Sweden)

    V. Chandrasekar

    2012-01-01

    Full Text Available Problem statement: Multicast is a concept of group communication which refers to transmitting the same data or messages from a source to multiple destinations in the network. This one-to-many group communication is a generalization of the concepts of one-to-one unicast and one-to-all broadcast. To deliver data from the sender to all receivers efficiently, routing plays an important role in multicast communication. In QoS multicast, every receiver must receive the data within their own specified QoS constraints. This becomes challenging especially if the network is a heterogeneous network made up of wired and wireless devices. Approach: This study investigates the performance of Protocol Independent Multicast-Sparse Mode (PIM-SM protocol in a heterogeneous network running an video conferencing application and proposes an enhanced routing protocol using Genetic Optimizing techniques to improve QOS parameters in the wireless part. Results and Conclusion: Extensive simulations were carried out using the proposed technique and existing PIM-SM. The proposed optimization technique not only improves the throughput of the network but also decreased the end to end delay."

  8. Employing Multicast in P2P Overlay Networks

    Science.gov (United States)

    Kolberg, Mario

    The work on multicast has evolved from bottom IP layer multicast to Application Layer Multicast. While there are issues with the dep-loyment of IP layer multicast, it outperforms Application Layer Multicast. However, the latter has the advantage of an easier dep-loyment. Furthermore, as will be illustrated later in this Chapter, IP layer multicast has the potential to make parallel overlay operations more efficient. Application Layer Multicast is primarily used to send application specific messages/data to a number of nodes.

  9. Dvnamic Retransmission Control for Reliable Mobile Multicast

    Institute of Scientific and Technical Information of China (English)

    LIN Yu(林宇); WU HaiTao(邬海涛); WANG ChongGang(王重钢); CHENG ShiDuan(程时端)

    2003-01-01

    Most existing multicast protocols adopt a static retransmission scheme (unicastor multicast) to retransmit lost packets. In the mobile multicast environment, static multicast re-transmission mode may lead to congestion in the receivers' wireless interfaces, while static unicastmode may result in great network load. Both static unicast and multicast retransmission modeswill cause a performance loss. This paper logically divides the mobile multicast network into fixedand mobile parts, and focuses on the mobile part. Then this paper analyzes the retransmissioncosts when multicast or unicast mode is chosen. Two main parameters are used to compare theirefficiencies: the average air-interface utilization of each receiver and the average network load.Based on the results of analysis, two new algorithms, called NLPA (Network Load Priority Algo-rithm) and AUPA (Air-interface Utilization Priority Algorithm) are presented. Finally, simulationresults conclude that, with proper parameters, both NLPA and AUPA can dynamically alternatebetween unicast and multicast retransmission modes according to the conditions of network andreceiver, and avoid congestion in receivers' wireless interfaces as well as great network load, witha better use of network and terminal resources.

  10. Providing resilience for carrier ethernet multicast traffic

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang

    2009-01-01

    This paper presents an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we detail how multicast traffic, which is essential for e.g. IPTV can be protected. We present Carrier Ethernet resilience methods for linear and ring networks and show by simulation...... that the availability of a multicast connection can be significantly increased by applying relevant resilience techniques....

  11. Multicast Routing Protocols in Adhoc Mobile networks

    Directory of Open Access Journals (Sweden)

    S.Nagaprasad,

    2010-11-01

    Full Text Available The majority of applications are in areas where rapid deployment and dynamic reconfiguration are necessary and a wire line network is not available. These include military battlefields, emergency search and rescue sites, classrooms, and conventions where participants share information dynamically using their mobile devices. Well established routing protocols do exist to offer efficient multicasting service in conventional wired networks. These protocols, having been designed for fixed networks, may fails to keep up with node movements and frequent topology changes in a MANET. Therefore, adapting existing wired multicast protocols as such to a MANET, which completely lacks infrastructure, appear less promising. Providing efficient multicasting over MANET faces many challenges, includes scalability,quality of service, reliable service, security, Address configuration, Applications for multicast over MANET. The existing multicast routing protocol do not addresses these issues effectively over Mobile Adhoc Networks (MANET.

  12. A Multicast Routing to Improve Multicast Capacity with Minimal Network Coding Cellsin WDM Networks

    Science.gov (United States)

    Liu, Huanlin; Zhou, Bangtao; Chen, Yong

    2014-12-01

    Multicast routing based on network coding can save large wavelength channels with high network coding operation costs for the all-optical WDM network. An optical multicast routing algorithm based on minimum network coding cells to reach the multicast max-flow is proposed in the paper. The algorithm selects path in the K shortest paths from source to each destination which meets the two criteria. One is to select paths making the least probability of dropping multicast max-flow. The other is to make the path lowest potential path coding cells in the K shortest paths. We investigate that the previously proposed multicast algorithms based on network coding choose the shortest paths or link-disjoint highest shared links to construct network coding sub-graph which may result in the large coding operation cost and decrease the possibility of getting the maximal multicast flow. The simulation results show that the proposed algorithm can effectively reduce the network coding cells and improve the possibility of achieving the multicast max-flow by using our designed two path selection criteria. In addition, the proposed multicast algorithm deteriorates a very limited multicast link costs which is very close to the lowest link costs. So, the proposed algorithm can get the cost-effective multicast routing for the optical networks.

  13. Routing in DiffServ multicast environment

    Science.gov (United States)

    Verma, Shekhar

    2002-07-01

    QOS aware applications have propelled the development of two complementary technologies, Multicasting and Differentiated Services. To provide the required QOS on the Internet, either the bandwidth needs to be increased (Multicasting) or limited bandwidth prioritized among users (DiffServ). Although, the bandwidth on the Internet is continually increasing, the backbone is still insufficient to support QOS without resource allocations. Hence, there is a need to map multicasting in a DiffServ Environment to conserve network bandwidth and to provision this bandwidth in an appropriate fashion. In this regard, two issues have to be addressed. One, the key difference between multicast and DiffServe routing is the structure of the multicast tree. This tree is maintained in multicast aware routers whereas in DiffServe, the core routers maintain no state information regarding the flows. Second, the task of restructuring the multicast tree when members join/leave. Currently, the first issue is addressed by embedding the multicast information within the packet itself as an additional header field. In this paper, we propose a neural network based heuristic approach to address the second problem of routing in a dynamic DiffServe Multicast environment. Many dynamic multicast routing algorithms have been proposed. The greedy algorithm creates a near optimal tree when a node is added but requires many query/reply messages. The PSPT algorithm cannot construct a cost optimal tree. The VTDM algorithm requires the estimated number of nodes that will join and is not flexible. The problem of building an optimal tree to satisfy QOS requirements at minimum cost and taking minimum network resources is NP- complete and none of the above solutions give an optimal solution. We have modeled this combinatorial optimization as a nonlinear programming problem and trained an artificial neural network to solve the problem. The problem is tractable only when the QOS parameters are combined into Diff

  14. MULTICAST ROUTING WITH QUALITY OF SERVICE CONSTRAINTS IN THE AD HOC WIRELESS NETWORKS

    Directory of Open Access Journals (Sweden)

    Abdellah Idrissi

    2014-01-01

    Full Text Available The recent multimedia applications and services are very demanding in terms of Quality of Service (QoS. This creates new challenges in ensuring QoS when delivering those services over wireless networks. Motivated by the need of supporting high quality multicast applications in wireless ad hoc networks, we propose a network topology that can minimize the power when connecting the source node to the destination nodes in multicast sessions with the respect of the QoS provisions. We formulated the problem as integer linear programming problem with a set of energy and QoS constraints. We minimize the total power of energy used by nodes while satisfying QoS constraints (Bandwidth and maximum delay that are crucial to wireless ad hoc network performance.

  15. Transactional interactive multimedia banner

    Science.gov (United States)

    Shae, Zon-Yin; Wang, Xiping; von Kaenel, Juerg

    2000-05-01

    Advertising in TV broadcasting has shown that multimedia is a very effective means to present merchandise and attract shoppers. This has been applied to the Web by including animated multimedia banner ads on web pages. However, the issues of coupling interactive browsing, shopping, and secure transactions e.g. from inside a multimedia banner, have only recently started to being explored. Currently there is an explosively growing amount of back-end services available (e.g., business to business commerce (B2B), business to consumer (B2C) commerce, and infomercial services) in the Internet. These services are mostly accessible through static HTML web pages at a few specific web portals. In this paper, we will investigate the feasibility of using interactive multimedia banners as pervasive access point for the B2C, B2B, and infomercial services. We present a system architecture that involves a layer of middleware agents functioning as the bridge between the interactive multimedia banners and back-end services.

  16. Storage format for personalized broadcasting content consumption

    Science.gov (United States)

    Jin, Sung Ho; Jang, Jea-Seok; Min, Hyun-Seok; Ro, Yong Man; Kim, Hui Yong

    2007-01-01

    In this paper, we propose a storage format which binds digital broadcasts with related data such as TV-Anytime metadata, additional multimedia resources, and personal viewing history. The goal of the proposed format is to make it possible to offer personalized content consumption after recording broadcasting contents to storage devices, e.g., HD-DVD and Blu-ray Disc. To achieve that, we adopt MPEG-4 file format as a container and apply a binary format for scenes (BIFS) for representing and rendering personal viewing history. In addition, TV-Anytime metadata is used to describe broadcasts and to refer to the additional multimedia resources, e.g, images, audio clips, and short video clips. To demonstrate the usefulness of the proposed format, we introduce an application scenario and test it on that scenario.

  17. Public Broadcasting.

    Science.gov (United States)

    Shooshan, Harry M.; Arnheim, Louise

    This paper, the second in a series exploring future options for public policy in the communications and information arenas, examines some of the issues underlying public broadcasting, primarily public television. It advances two reasons why quality local public television programming is scarce: funds for the original production of programming have…

  18. Single-Source Oriented Application Level Multicast

    Institute of Scientific and Technical Information of China (English)

    PI Ren-jie; SONG Jun-de

    2004-01-01

    Using application level multicast can partly pad the lack of IP multicast deployment. To perform single-source applications in hierarchical topology, we propose an application level multicast approach, Hierarchical Topology Aware Grouping (HTAG), which exploits information about path overlap among members and topological hierarchy to construct overlay tree at different network layers. We present simulations of both our protocol and the TAG over generated hierarchical topologies. The results indicate the effectiveness of our approach in reducing duplicate packets and preserving available bandwidth, with reasonable delays increase.

  19. Research on performance of multicasting in optical packet switched networks

    Institute of Scientific and Technical Information of China (English)

    Xin Liu; Yuefeng Ji; Lin Bai; Hongxiang Wang; Yongmei Sun

    2009-01-01

    @@ Different multicasting schemes in optical packet switched networks are discussed, including the parallel mode, serial mode, and hybrid mode multicasting schemes.Simulated modeling technique is applied to compare the network-level performance of the three multicasting schemes.A conclusion can be drawn from the results that since the hybrid-mode multicasting scheme can increase the multicast success ratio and reduce the packet retransmission times compared with the other two schemes, it is the best choice for delivering multicasting sessions in the optical packet switched networks.

  20. The reliable multicast protocol application programming interface

    Science.gov (United States)

    Montgomery , Todd; Whetten, Brian

    1995-01-01

    The Application Programming Interface for the Berkeley/WVU implementation of the Reliable Multicast Protocol is described. This transport layer protocol is implemented as a user library that applications and software buses link against.

  1. Evaluating multicast resilience in carrier ethernet

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang;

    2010-01-01

    This paper gives an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we show how multicast traffic, which is essential for IPTV can be protected. We detail the ackground for resilience mechanisms and their control and e present Carrier Ethernet...... resilience methods for linear nd ring networks. By simulation we show that the vailability of a multicast connection can be significantly increased by applying protection methods....

  2. Evaluating multicast resilience in carrier ethernet

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang

    2010-01-01

    This paper gives an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we show how multicast traffic, which is essential for IPTV can be protected. We detail the ackground for resilience mechanisms and their control and e present Carrier Ethernet...... resilience methods for linear nd ring networks. By simulation we show that the vailability of a multicast connection can be significantly increased by applying protection methods....

  3. ISMuS: interactive, scalable, multimedia streaming platform

    Science.gov (United States)

    Cha, Jihun; Kim, Hyun-Cheol; Jeong, Seyoon; Kim, Kyuheon; Patrikakis, Charalampos; van der Schaar, Mihaela

    2005-08-01

    Technical evolutions in the field of information technology have changed many aspects of the industries and the life of human beings. Internet and broadcasting technologies act as core ingredients for this revolution. Various new services that were never possible are now available to general public by utilizing these technologies. Multimedia service via IP networks becomes one of easily accessible service in these days. Technical advances in Internet services, the provision of constantly increasing network bandwidth capacity, and the evolution of multimedia technologies have made the demands for multimedia streaming services increased explosively. With this increasing demand Internet becomes deluged with multimedia traffics. Although multimedia streaming services became indispensable, the quality of a multimedia service over Internet can not be technically guaranteed. Recently users demand multimedia service whose quality is competitive to the traditional TV broadcasting service with additional functionalities. Such additional functionalities include interactivity, scalability, and adaptability. A multimedia that comprises these ancillary functionalities is often called richmedia. In order to satisfy aforementioned requirements, Interactive Scalable Multimedia Streaming (ISMuS) platform is designed and developed. In this paper, the architecture, implementation, and additional functionalities of ISMuS platform are presented. The presented platform is capable of providing user interactions based on MPEG-4 Systems technology [1] and supporting an efficient multimedia distribution through an overlay network technology. Loaded with feature-rich technologies, the platform can serve both on-demand and broadcast-like richmedia services.

  4. Multipoint Multimedia Conferencing System with Group Awareness Support and Remote Management

    Science.gov (United States)

    Osawa, Noritaka; Asai, Kikuo

    2008-01-01

    A multipoint, multimedia conferencing system called FocusShare is described that uses IPv6/IPv4 multicasting for real-time collaboration, enabling video, audio, and group awareness information to be shared. Multiple telepointers provide group awareness information and make it easy to share attention and intention. In addition to pointing with the…

  5. Multimedia Information Extraction

    CERN Document Server

    Maybury, Mark T

    2012-01-01

    The advent of increasingly large consumer collections of audio (e.g., iTunes), imagery (e.g., Flickr), and video (e.g., YouTube) is driving a need not only for multimedia retrieval but also information extraction from and across media. Furthermore, industrial and government collections fuel requirements for stock media access, media preservation, broadcast news retrieval, identity management, and video surveillance.  While significant advances have been made in language processing for information extraction from unstructured multilingual text and extraction of objects from imagery and vid

  6. Multimedia Retrieval

    NARCIS (Netherlands)

    Blanken, H.M.; Vries, de A.P.; Blok, H.E.; Feng, L.

    2007-01-01

    Retrieval of multimedia data is different from retrieval of structured data. A key problem in multimedia databases is search, and the proposed solutions to the problem of multimedia information retrieval span a rather wide spectrum of topics outside the traditional database area, ranging from inform

  7. Policies and Economics of Digital Multimedia Transmission

    CERN Document Server

    Gerami, Mohsen

    2010-01-01

    There are different Standards of digital multimedia transmission, for example DVB in Europe and ISDB in Japan and DMB in Korea, with different delivery system (example MPEG-2, MPEG-4).This paper describe an overview of Digital Multimedia Transmission (DMT) technologies. The economic aspects of digital content & software solution industry as a strategic key in the future will be discussed. The study then focuses on some important policy and technology issues, such S-DMB, T-DMB, Digital Video Broadcasting Handheld (DVB-H) and concludes DMT policies for convergence of telecommunications and broadcasting.

  8. Policies and Economics of Digital Multimedia Transmission

    Directory of Open Access Journals (Sweden)

    Mohsen Gerami

    2010-03-01

    Full Text Available There are different Standards of digital multimedia transmission, for example DVB in Europe and ISDB in Japan and DMB in Korea, with different delivery system (example MPEG-2, MPEG-4.This paper describe an overview of Digital Multimedia Transmission (DMT technologies. The economic aspects of digital content and software solution industry as a strategic key in the future will be discussed. The study then focuses on some important policy and technology issues, such S-DMB, T-DMB, Digital Video Broadcasting Handheld (DVB-H and concludes DMT policies for convergence of telecommunications and broadcasting.

  9. Storage and distribution system for multimedia information

    Science.gov (United States)

    Murakami, Tokumichi

    1994-06-01

    Recent advances in technologies such as digital signal processing, LSI devices and storage media have led to an explosive growth in multimedia environment. Multimedia information services are expected to provide an information-oriented infrastructure which will integrate visual communication, broadcasting and computer services. International standardizations in video/audio coding accelerate permeation of these services into society. In this paper, from trends of R & D and international standardization in video coding techniques, an outline is given of a storage and distribution system for multimedia information, and a summary of the requirements of digital storage media.

  10. Efficient Cluster Based Multicast Tree for Secure Multicast Communication for Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    D.Suganya Devi

    2010-05-01

    Full Text Available Secure multicast communication in mobile adhoc networks is challenging due to its inherent characteristics of infrastructure-less architecture with lack of central authority, limited resources such as bandwidth, time and power. Hence key management is the fundamental challenge in achieving secure communication using multicast key distribution in mobile adhoc networks. In many multicast interactions, due to its frequent node mobility, new member can join and current members can leave at a time due to node failure which causes delay in multicast transmission. This paper proposes a new efficient cluster based multicast tree (CBMT algorithm for secure multicast Communication, in which source node uses Multicast version of Destination Sequenced Distance Vector(MDSDV routing protocol to collects its 1 hop neighbors to form cluster and each node which have child node is elected as the Local controllers of the created clusters. It also tolerates the faults that causes due to failure of nodes. Simulation results shows the demonstration of CBMT using MDSDV have better system performance in terms of end to end delay and fault tolerance rate under varying network conditions.

  11. Security in Multicasting System with Diversity Combining Techniques

    Directory of Open Access Journals (Sweden)

    Rosni Sayed

    2016-10-01

    Full Text Available This paper is concerned with a Rayleigh fading multicasting SIMO network, where a single source transmits to a group of users in the presence of an eavesdropper. We consider selection combining (SC and maximal ratio combining (MRC diversity techniques at the receivers and eavesdropper. We derive the closed-form analytical expressions for the probability of nonzero secrecy multicast capacity, and ergodic secrecy multicast capacity. This analysis shows, how the channel diversity enhances security in multicast channels. We also present a comparison between SC and MRC diversity techniques to show which technique is better for secure wireless multicasting.

  12. Secluding Efficient Geographic Multicast Protocol against Multicast Attacks

    Directory of Open Access Journals (Sweden)

    A. Amuthan

    2013-09-01

    Full Text Available A Mobile Ad-hoc Network (MANETs is composed of Mobile Nodes without any infrastructure. The network nodes in MANETs, not only act as ordinary network nodes but also as the routers for other peer devices. The dynamic topology, lack of a fixed infrastructure and the wireless nature make MANETs susceptible to the security attacks. To add to that, due to the inherent, severe constraints in power, storage and computational resources in the MANET nodes, incorporating sound defense mechanisms against such attacks is also non-trivial. Therefore, interest in research of Mobile Ad-hoc NETworks has been growing since last few years. Security is a big issue in MANETs as they are infrastructure-less and autonomous. The main objective of this paper is to address some basic security concerns in EGMP protocol which is a multicast protocol found to be more vulnerable towards attacks like blackhole, wormhole and flooding attacks. The proposed technique uses the concepts of certificate to prevent these attacks and to find the malicious node. These attacks are simulated using NS2.28 version and the proposed proactive technique is implemented. The following metrics like packet delivery ratio, control overhead, total overhead and End to End delay are used to prove that the proposed solution is secure and robust.

  13. Keyphrase Cloud Generation of Broadcast News

    OpenAIRE

    Marujo, Luis; Viveiros, Márcio; Neto, João Paulo da Silva

    2013-01-01

    This paper describes an enhanced automatic keyphrase extraction method applied to Broadcast News. The keyphrase extraction process is used to create a concept level for each news. On top of words resulting from a speech recognition system output and news indexation and it contributes to the generation of a tag/keyphrase cloud of the top news included in a Multimedia Monitoring Solution system for TV and Radio news/programs, running daily, and monitoring 12 TV channels and 4 Radios.

  14. Scalable Energy Efficient Location Aware Multicast Protocol for MANET (SEELAMP)

    CERN Document Server

    Kamboj, Pariza

    2010-01-01

    Multicast plays an important role in implementing the group communications in bandwidth scarce multihop mobile ad hoc networks. However, due to the dynamic topology of MANETs it is very difficult to build optimal multicast trees and maintaining group membership, making even more challenging to implement scalable and robust multicast in Mobile Ad hoc Networks (MANET). A scalable and energy efficient location aware multicast algorithm, called SEELAMP, for mobile ad hoc networks is presented in the paper that is based on creation of shared tree using the physical location of the nodes for the multicast sessions. It constructs a shared bi-directional multicast tree for its routing operations rather than a mesh, which helps in achieving more efficient multicast delivery. The algorithm uses the concept of small overlapped zones around each node for proactive topology maintenance with in the zone. Protocol depends on the location information obtained using a distributed location service, which effectively reduces th...

  15. Reliable adaptive multicast protocol in wireless Ad hoc networks

    Institute of Scientific and Technical Information of China (English)

    Sun Baolin; Li Layuan

    2006-01-01

    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.

  16. On Satellite Multicast to Heterogeneous Receivers

    Science.gov (United States)

    2001-01-01

    combined into one bulk file. Let the multicast source use Reed-Solomon erasure ( RSE ) coding (e.g. [Mac97]) and let the bulk file be encoded into W ≥ 1... RSE -based FEC blocks. Each FEC block consists of h data packets and c parity packets – all of the same length. We assume a multicast tree that has a... RSE -based FEC block, a receiver must receive at least h distinct packets, either data or parity, from the same FEC block. To allow a systematic way

  17. Approche cross-layer pour services multimedia évolutifs distribués sur la prochaine génération de réseaux convergents : architectures et performances

    OpenAIRE

    Le, Tien Anh

    2012-01-01

    Multimedia services are the killer applications on next generation convergent networks. Video contents are the most resource consuming part of a multimedia flux. Video transmission, video multicast and video conferencing services are the most popular types of video communication with increasing difficulty levels. Four main parts of the distributed cross-layer scalable multimedia services over next generation convergent networks are considered in this research work, both from the architecture ...

  18. Protection of multicast scalable video by secret sharing: simulation results

    Science.gov (United States)

    Eskicioglu, Ahmet M.; Dexter, Scott; Delp, Edward J., III

    2003-06-01

    Security is an increasingly important attribute for multimedia applications that require prevention of unauthorized access to copyrighted data. Two approaches have been used to protect scalable video content in distribution: Partial encryption and progressive encryption. Partial encryption provides protection for only selected portions of the video. Progressive encryption allows transcoding with simple packet truncation, and eliminates the need to decrypt the video packets at intermediate network nodes with low complexity. Centralized Key Management with Secret Sharing (CKMSS) is a recent approach in which the group manager assigns unique secret shares to the nodes in the hierarchical key distribution tree. It allows the reconstruction of different keys by communicating different activating shares for the same prepositioned information. Once the group key is established, it is used until a member joins/leaves the multicast group or periodic rekeying occurs. In this paper, we will present simulation results regarding the communication and processing requirements of the CKMSS scheme applied to scalable video. In particular, we have measured the rekey message size and the processing time needed by the server for each join/leave request and periodic rekey event.

  19. Providing resilience for carrier ethernet multicast traffic

    DEFF Research Database (Denmark)

    Ruepp, Sarah Renée; Wessing, Henrik; Zhang, Jiang

    2009-01-01

    This paper presents an overview of the Carrier Ethernet technology with specific focus on resilience. In particular, we detail how multicast traffic, which is essential for e.g. IPTV can be protected. We present Carrier Ethernet resilience methods for linear and ring networks and show by simulation...

  20. Performance of Superposition Coded Broadcast/Unicast Service Overlay System

    Science.gov (United States)

    Yoon, Seokhyun; Kim, Donghee

    The system level performance of a superposition coded broadcast/unicast service overlay system is considered. Cellular network for unicast service only is considered as interference limited system, where increasing the transmission power does not help improve the network throughput especially when the frequency reuse factor is close to 1. In such cases, the amount of power that does not contribute to improving the throughput can be considered as “unused.” This situation motivates us to use the unused power for broadcast services, which can be efficiently provided in OFDM based single frequency networks as in digital multimedia broadcast systems. In this paper, we investigate the performance of such a broadcast/unicast overlay system in which a single frequency broadcast service is superimposed over a unicast cellular service. Alternative service multiplexing using FDM/TDM is also considered for comparison.

  1. Conflict-Aware Relay Selection for Multicast in MUD based Wireless Networks

    Directory of Open Access Journals (Sweden)

    Asma Ben Hassouna

    2013-04-01

    Full Text Available Multipoint Relays (MPR [1] selection is a good step toward building a very proficient routing scheme for multicast/broadcast communications. It considers the fact that data transmitted by a node is overheard by all the users in the sender’s communication range, called the Wireless Broadcast Advantage (WBA [2][4][6]. However, when a node elects its MPR nodes it does not consider their channel qualities (i.e. they do not consider the Multi-User Diversity (MUD [3][5] factor, that has a significant influence on the network performance. Many other works consider the MUD and the rate adaptation (RA features [15][16]. However these works are distorted by severe simplifications that are made about some common wireless network problems such as: the number of transmissions, the access scheduling, the interference conflicts, etc. In this paper, we introduce three new MUD, WBA and RA based relay selection schemes. The first one proposed, called the Efficient Multi-user Diversity based Relay (E-MDR selection scheme,  is done over steps by exploiting the channel qualities in term of maximum achievable data rate (or channel capacity. The proposed EMDR based flooding strategy achieves the best multicast throughput without considering concurrent transmissions. It aims jointly (i to reduce the number of relays, (ii to maximize the throughput of each single multicast session (or partition, (iii to reduce the number of transmissions, (iv to exploit extremely the offered link capacities and as a consequence (v to enhance the allover network throughput. The second MUD, WBA and RA based relay selection scheme, called the Conflict free Multi-user Diversity based Relay (C-MDR selection scheme, performs relay selection with consideration of the interference factor. It targets (i to select relay nodes and their data transmission rates that maximize the multicast throughput, (ii to consider the effect of access scheduling when choosing relay nodes and (iii to resolve

  2. Intelligent Broadcasting in Mobile Ad Hoc Networks: Three Classes of Adaptive Protocols

    Directory of Open Access Journals (Sweden)

    Colagrosso Michael D

    2007-01-01

    Full Text Available Because adaptability greatly improves the performance of a broadcast protocol, we identify three ways in which machine learning can be applied to broadcasting in a mobile ad hoc network (MANET. We chose broadcasting because it functions as a foundation of MANET communication. Unicast, multicast, and geocast protocols utilize broadcasting as a building block, providing important control and route establishment functionality. Therefore, any improvements to the process of broadcasting can be immediately realized by higher-level MANET functionality and applications. While efficient broadcast protocols have been proposed, no single broadcasting protocol works well in all possible MANET conditions. Furthermore, protocols tend to fail catastrophically in severe network environments. Our three classes of adaptive protocols are pure machine learning, intra-protocol learning, and inter-protocol learning. In the pure machine learning approach, we exhibit a new approach to the design of a broadcast protocol: the decision of whether to rebroadcast a packet is cast as a classification problem. Each mobile node (MN builds a classifier and trains it on data collected from the network environment. Using intra-protocol learning, each MN consults a simple machine model for the optimal value of one of its free parameters. Lastly, in inter-protocol learning, MNs learn to switch between different broadcasting protocols based on network conditions. For each class of learning method, we create a prototypical protocol and examine its performance in simulation.

  3. Intelligent Broadcasting in Mobile Ad Hoc Networks: Three Classes of Adaptive Protocols

    Directory of Open Access Journals (Sweden)

    Michael D. Colagrosso

    2006-11-01

    Full Text Available Because adaptability greatly improves the performance of a broadcast protocol, we identify three ways in which machine learning can be applied to broadcasting in a mobile ad hoc network (MANET. We chose broadcasting because it functions as a foundation of MANET communication. Unicast, multicast, and geocast protocols utilize broadcasting as a building block, providing important control and route establishment functionality. Therefore, any improvements to the process of broadcasting can be immediately realized by higher-level MANET functionality and applications. While efficient broadcast protocols have been proposed, no single broadcasting protocol works well in all possible MANET conditions. Furthermore, protocols tend to fail catastrophically in severe network environments. Our three classes of adaptive protocols are pure machine learning, intra-protocol learning, and inter-protocol learning. In the pure machine learning approach, we exhibit a new approach to the design of a broadcast protocol: the decision of whether to rebroadcast a packet is cast as a classification problem. Each mobile node (MN builds a classifier and trains it on data collected from the network environment. Using intra-protocol learning, each MN consults a simple machine model for the optimal value of one of its free parameters. Lastly, in inter-protocol learning, MNs learn to switch between different broadcasting protocols based on network conditions. For each class of learning method, we create a prototypical protocol and examine its performance in simulation.

  4. Quantum broadcast communication

    Institute of Scientific and Technical Information of China (English)

    Wang Jian; Zhang Quan; Tang Chao-Jing

    2007-01-01

    Broadcast encryption allows the sender to securely distribute his/her secret to a dynamically changing group of users over a broadcast channel. In this paper, we just take account of a simple broadcast communication task in quantum scenario, in which the central party broadcasts his secret to multi-receiver via quantum channel. We present three quantum broadcast communication schemes. The first scheme utilizes entanglement swapping and GreenbergerHorne-Zeilinger state to fulfil a task that the central party broadcasts the secret to a group of receivers who share a group key with him. In the second scheme, based on dense coding, the central party broadcasts the secret to multi-receiver,each of which shares an authentication key with him. The third scheme is a quantum broadcast communication scheme with quantum encryption, in which the central party can broadcast the secret to any subset of the legal receivers.

  5. Hybrid Multicast Transmission for Public Safety Network in 5G

    Directory of Open Access Journals (Sweden)

    Fei Qi

    2016-01-01

    Full Text Available We investigate the application of wireless multicast technology in public safety network (PSN in future wireless communication system. The hybrid unicast/multicast transmission system is proposed and analyzed in 3D massive multi-input multioutput (MIMO channel. The mutual coupling channel model is adopted under the different antenna array configuration scenarios. The proposed hybrid system adopts multicast beamforming in the multicast groups as well as multiuser-MIMO (MU-MIMO linear precoding in the unicast group to increase system throughput. The null space method based interference cancellation is further performed between each group to eliminate signal leakage generated from each group. Comparisons between two types of antenna array configurations, different channel models, linear precoding as well as multicast beamforming, and user grouping strategies for multicast services are presented and analyzed by simulation.

  6. On locality of Generalized Reed-Muller codes over the broadcast erasure channel

    KAUST Repository

    Alloum, Amira

    2016-07-28

    One to Many communications are expected to be among the killer applications for the currently discussed 5G standard. The usage of coding mechanisms is impacting broadcasting standard quality, as coding is involved at several levels of the stack, and more specifically at the application layer where Rateless, LDPC, Reed Slomon codes and network coding schemes have been extensively studied, optimized and standardized in the past. Beyond reusing, extending or adapting existing application layer packet coding mechanisms based on previous schemes and designed for the foregoing LTE or other broadcasting standards; our purpose is to investigate the use of Generalized Reed Muller codes and the value of their locality property in their progressive decoding for Broadcast/Multicast communication schemes with real time video delivery. Our results are meant to bring insight into the use of locally decodable codes in Broadcasting. © 2016 IEEE.

  7. A Heuristic Algorithm for QoS Multicast Routing

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In recent years, QoS multicast routing has continued to be a very important research topic in the areas of net-works. This paper presents a heuristic algorithm for the QoS multicast routing (HAQMR). This heuristic algorithmdeals with delay and bandwidth constraints and has low cost. The HAQMR attempts to significantly reduce the overheadfor constructing a multicast tree. the proof for correctness of the HAQMR is given, and the performance of the HAQMRis evaluated by simulations. The study shows that HAQMR provides an available approach to QoS multicast routing.

  8. Efficient Multicast Support in High-Speed Packet Switches

    Directory of Open Access Journals (Sweden)

    Lotfi Mhamdi

    2007-06-01

    Full Text Available The tremendous growth of the Internet coupled with newly emerging applications has created a vital need for multicast traffic support by backbone routers and ATM switches. Considerable research work has been done on Input Queued (IQ switches to handle multicast traffic flows. Unfortunately, all previously proposed solutions were of no practical value because they either lack performance or were simply too complex to implement. Internally Buffered Crossbar (IBC switches, where a limited small amount of memory is added in each crosspoint of the crossbar fabric, on the other hand, have been considered as a robust alternative to buffer-less crossbar switches to improve the switching performance. However, very little has been done on multicasting in IBC switches. In this paper, we fill this gap and study the multicasting problem in IBC switches. In particular, we propose a novel IBC based multicast architecture along with a simple scheduling scheme named Multicast cross-point Round Robin (MXRR. Our scheme was shown to handle multicast traffic more efficiently and far better than all previous schemes for both the multicast FIFO architecture as well as the multicast k FIFO queues architecture. Yet, MXRR is both practical and achieves high performance.

  9. An Optimal Multicast Algorithm for Cube-Connected Cycles

    Institute of Scientific and Technical Information of China (English)

    宋建平; 侯紫峰; 史云涛

    2000-01-01

    This paper presents an efficient algorithm that implements oneto-many, or multicast, communication in one-port wormhole-routed cube-connected cycles (CCCs) in the absence of hardware multicast support. By exploiting the properties of the switching technology and the use of virtual channels, a minimumtime multicast algorithm is presented for n-dimensional CCCs that use deterministic routing of unicast messages. The algorithm can deliver a multicast message to m - 1destinations in [log2 m] message-passing steps, while avoiding contention among the constituent unicast messages. Performance results of a simulation study on CCCs with up to 10,240 nodes are also given.

  10. Dynamic multicast traffic grooming in WDM networks

    Institute of Scientific and Technical Information of China (English)

    CHENG Xiao-jun; GE Ning; FENG Chong-xi

    2006-01-01

    Dynamic multicast traffic grooming in wavelength division multiplexing (WDM) networks was analyzed to minimize networkwide costs and to increase the network resource utilization.A network model was developed for dynamic multicast traffic grooming with resource constraints and an algorithm that can provide quality of service (QoS)was proposed.The QoS is measured by the maximum number of lightpaths passing between the source and the destinations.The blocking probability of the algorithm was assessed in simulations.The results show that a higher QoS requirement results in higher blocking probability,and when the QoS requirement is low,changes in the QoS requirements have only small effects on the blocking probability.

  11. Performance optimization for multicast packet authentication

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    In secure multicast, one of the challenging problems is the authentication of multicast packets. This paper presents a novel scheme to address this problem, which combines ideas in both the hash tree schemes and the hash chain schemes. In this scheme, a group of packets is partitioned into equal-sized subgroups. Then a Merkle hash tree is built for each subgroup of packets, and the hash value of every root is appended to preceding packets to form hash chains. Its performance is analyzed and simulated using Biased Coin Toss loss model and 2-state Markov Chain loss model, respectively. Compared with the original hash chain schemes, results show that this scheme is much more efficient in term of communication overhead.

  12. Fault recovery in the reliable multicast protocol

    Science.gov (United States)

    Callahan, John R.; Montgomery, Todd L.; Whetten, Brian

    1995-01-01

    The Reliable Multicast Protocol (RMP) provides a unique, group-based model for distributed programs that need to handle reconfiguration events at the application layer. This model, called membership views, provides an abstraction in which events such as site failures, network partitions, and normal join-leave events are viewed as group reformations. RMP provides access to this model through an application programming interface (API) that notifies an application when a group is reformed as the result of a some event. RMP provides applications with reliable delivery of messages using an underlying IP Multicast (12, 5) media to other group members in a distributed environment even in the case of reformations. A distributed application can use various Quality of Service (QoS) levels provided by RMP to tolerate group reformations. This paper explores the implementation details of the mechanisms in RMP that provide distributed applications with membership view information and fault recovery capabilities.

  13. Tunable Sparse Network Coding for Multicast Networks

    DEFF Research Database (Denmark)

    Feizi, Soheil; Roetter, Daniel Enrique Lucani; Sørensen, Chres Wiant

    2014-01-01

    complexity. At the end of a transmission, when receivers have accumulated degrees of freedom, coding density is increased. We propose a family of tunable sparse network codes (TSNCs) for multicast erasure networks with a controllable trade-off between completion time performance to decoding complexity...... a mechanism to perform efficient Gaussian elimination over sparse matrices going beyond belief propagation but maintaining low decoding complexity. Supporting simulation results are provided showing the trade-off between decoding complexity and completion time....

  14. Performance Analysis of Dual-Priority Multilayer Multistage Interconnection Networks under Multicast Environment

    Directory of Open Access Journals (Sweden)

    Dimitris C. Vasiliadis

    2011-06-01

    Full Text Available Next-generation network architectures strive to achieve high bandwidth and ultralow latency for the packets traversing the offered end-to-end paths. Multistage Interconnection Networks (MINs are often employed for implementing NGNs, but while MINs are fairly flexible in handling varieties of traffic loads, they tend to quickly saturate under broadcast and multicast traffic, especially at increasing size networks. As a response to this issue, multilayer MINs have been proposed, however their performance prediction and evaluation has not been studied sufficiently insofar. In this paper, we evaluate and discuss the performance of multilayer MINs under multicast traffic, considering also two levels of packet priorities, since support for multiple QoS levels is an indispensible requirement for NGNs. Different offered loads and buffer size configurations are examined in this context, and performance results are given for the two most important network performance factors, namely packet throughput and delay. We also introduce and calculate a universal performance fac­tor, which includes the importance aspect of each of the above main performance factors. The findings of this study can be used by NGN system designers in order to predict the performance of each configuration and adjust the design of their communication infrastructure to the traffic requirements at hand.

  15. Cross-Layer Designs in Coded Wireless Fading Networks with Multicast

    CERN Document Server

    Rajawat, Ketan; Giannakis, Georgios B

    2010-01-01

    A cross-layer design along with an optimal resource allocation framework is formulated for wireless fading networks, where the nodes are allowed to perform network coding. The aim is to jointly optimize end-to-end transport layer rates, network code design variables, broadcast link flows, link capacities, average power consumption, and short-term power allocation policies. As in the routing paradigm where nodes simply forward packets, the cross-layer optimization problem with network coding is non-convex in general. It is proved however, that with network coding, dual decomposition for multicast is optimal so long as the fading at each wireless link is a continuous random variable. This lends itself to provably convergent subgradient algorithms, which not only admit a layered-architecture interpretation but also optimally integrate network coding in the protocol stack. The dual algorithm is also paired with a scheme that yields near-optimal network design variables, namely multicast end-to-end rates, network ...

  16. Context based multimedia information retrieval

    DEFF Research Database (Denmark)

    Mølgaard, Lasse Lohilahti

    with the help of contextual knowledge. Our approach to model the context of multimedia is based on unsupervised methods to automatically extract meaning. We investigate two paths of context modelling. The first part extracts context from the primary media, in this case broadcast news speech, by extracting...... through an approximation based on non-negative matrix factorisation NMF. The second part of the work tries to infer the contextual meaning of music based on extra-musical knowledge, in our case gathered from Wikipedia. The semantic relations between artists are inferred using linking structure...

  17. Scalable Overlay Multicasting in Mobile Ad Hoc Networks (SOM

    Directory of Open Access Journals (Sweden)

    Pariza Kamboj

    2010-10-01

    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.

  18. A Secure and Stable Multicast Overlay Network with Load Balancing for Scalable IPTV Services

    Directory of Open Access Journals (Sweden)

    Tsao-Ta Wei

    2012-01-01

    Full Text Available The emerging multimedia Internet application IPTV over P2P network preserves significant advantages in scalability. IPTV media content delivered in P2P networks over public Internet still preserves the issues of privacy and intellectual property rights. In this paper, we use SIP protocol to construct a secure application-layer multicast overlay network for IPTV, called SIPTVMON. SIPTVMON can secure all the IPTV media delivery paths against eavesdroppers via elliptic-curve Diffie-Hellman (ECDH key exchange on SIP signaling and AES encryption. Its load-balancing overlay tree is also optimized from peer heterogeneity and churn of peer joining and leaving to minimize both service degradation and latency. The performance results from large-scale simulations and experiments on different optimization criteria demonstrate SIPTVMON's cost effectiveness in quality of privacy protection, stability from user churn, and good perceptual quality of objective PSNR values for scalable IPTV services over Internet.

  19. Security Challenges in Multicast Communication for Mobile Ad Hoc Network

    Directory of Open Access Journals (Sweden)

    S. Gunasekaran

    2010-01-01

    Full Text Available Problem statement: Multicasting communication network accepted a single message from an application and delivered copies of the message to multiple recipients at different locations. Recently, there has been an explosion of research literature on multicast communication environment. The objective of this study were to contribute the complexity of supporting current multicast applications, (i the lack of reliable multicast transport mechanisms at the network level and (ii the lack of network support for large scale multicast communication. The scaling problem of secure multicast key distribution compounded for the case where sender-specific keys need to be distributed to a group and required for sender-specific authentication of data traffic and minimize control overhead (iii compare RC4, AES-128,RS(2 and RS(3 computation time of both algorithms. Approach: Algorithms were collected and performed computation time. In general the multicast key distribution scheme implemented for distributing 128 bit session keys. Thus the Maximum Distance Separable Codes (MDS Codes needed for their encoding and decoding process. In rekeying scheme errors were occurred during over period of time or at a particular point of time and to eliminate all these errors in the level of encryption and decryption mechanism. The MDS codes played an important role in providing security services for multicast, such as traffic, integrity, authentication and confidentiality, is particularly problematic since it requires securely distributing a group (session key to each of a group’s receivers. Results: First we showed that internet multicasting algorithms based on reverse path forwarding were inherently unreliable and present a source-tree-based reliable multicasting scheme also. The new scheme proposed and used as an inter-gateway protocol and worked on top of the previously developed distance vector and link state internet routing schemes. Next, to support large scale

  20. Secure Multicast Routing Algorithm for Wireless Mesh Networks

    Directory of Open Access Journals (Sweden)

    Rakesh Matam

    2016-01-01

    Full Text Available Multicast is an indispensable communication technique in wireless mesh network (WMN. Many applications in WMN including multicast TV, audio and video conferencing, and multiplayer social gaming use multicast transmission. On the other hand, security in multicast transmissions is crucial, without which the network services are significantly disrupted. Existing secure routing protocols that address different active attacks are still vulnerable due to subtle nature of flaws in protocol design. Moreover, existing secure routing protocols assume that adversarial nodes cannot share an out-of-band communication channel which rules out the possibility of wormhole attack. In this paper, we propose SEMRAW (SEcure Multicast Routing Algorithm for Wireless mesh network that is resistant against all known active threats including wormhole attack. SEMRAW employs digital signatures to prevent a malicious node from gaining illegitimate access to the message contents. Security of SEMRAW is evaluated using the simulation paradigm approach.

  1. Multicast Routing Problem Using Tree-Based Cuckoo Optimization Algorithm

    Directory of Open Access Journals (Sweden)

    Mahmood Sardarpour

    2016-06-01

    Full Text Available The problem of QoS multicast routing is to find a multicast tree with the least expense/cost which would meet the limitations such as band width, delay and loss rate. This is a NP-Complete problem. To solve the problem of multicast routing, the entire routes from the source node to every destination node are often recognized. Then the routes are integrated and changed into a single multicast tree. But they are slow and complicated methods. The present paper introduces a new tree-based optimization method to overcome such weaknesses. The recommended method directly optimizes the multicast tree. Therefore a tree-based typology including several spanning trees is created which combines the trees two by two. For this purpose, the Cuckoo Algorithm is used which is proved to be well converged and makes quick calculations. The simulation conducted on different types of network typologies proved that it is a practical and influential algorithm.

  2. Methods and Applications in Interactive Broadcasting

    Directory of Open Access Journals (Sweden)

    George Lekakos

    2007-09-01

    Full Text Available Interactive TV technology has been addressed in many previous works, but there is sparse research on the topic of interactive content broadcasting and how to support the production process. In this article, the interactive broadcasting process is broadly defined to include studio technology and digital TV applications at consumer set-top boxes. In particular, augmented reality studio technology employs smart-projectors as light sources and blends real scenes with interactive computer graphics that are controlled at end-user terminals. Moreover, TV producer-friendly multimedia authoring tools empower the development of novel TV formats. Finally, the support for user-contributed content raises the potential to revolutionize the hierarchical TV production process, by introducing the viewer as part of content delivery chain.

  3. 无线网络终端协作多播技术研究%Cooperative Multicast Scheme Research in Wireless Networks

    Institute of Scientific and Technical Information of China (English)

    谢飞

    2014-01-01

    终端协作多播技术,因其能有效改善广播多播吞吐量的瓶颈问题而成为新的研究方向。针对当前多媒体广播多播业务的流行,对传统广播多播的缺点做了简要分析,介绍了协作通信与协作多播的基本原理,重点分析了当前国内外协作多播技术的研究现状,从中继节点的协作方式、协作策略与协作中继选择、多阶段协作多播三方面展开阐述,概括出当前的研究主要集中于提高吞吐量与降低系统功耗两方面。最后,对协作多播提出了展望,说明了协作多播走向商用还需解决的问题。%Multicast communication is an efficient mechanism for one-to-many transmissions over a broadcast wireless channel,but the group member with the worst channel condition becomes the bottleneck and results in conservative resource utilization. Cooperative multicast has gotten much attention because it can achieve high throughput than existing multicast scheme.A detailed introduction of the research status of cooperative multicast is given in this article,from which we find that most researches focus on the relay selection and the energy efficient cooperative multicast scheme.

  4. Radio broadcasting via satellite

    Science.gov (United States)

    Helm, Neil R.; Pritchard, Wilbur L.

    1990-10-01

    Market areas offering potential for future narrowband broadcast satellites are examined, including international public diplomacy, government- and advertising-supported, and business-application usages. Technical issues such as frequency allocation, spacecraft types, transmission parameters, and radio receiver characteristics are outlined. Service and system requirements, advertising revenue, and business communications services are among the economic issues discussed. The institutional framework required to provide an operational radio broadcast service is studied, and new initiatives in direct broadcast audio radio systems, encompassing studies, tests, in-orbit demonstrations of, and proposals for national and international commercial broadcast services are considered.

  5. Link-Aware Nice Application Level Multicast Protocol

    Directory of Open Access Journals (Sweden)

    Dina Helal

    2014-06-01

    Full Text Available Multicast is one of the most efficient ways to distribute data to multiple users. There are different types of Multicast such as IP Multicast, Overlay Multicast, and Application Layer Multicast (ALM. In this paper, we present a link-aware Application Layer (ALM Multicast algorithm. Our proposed algorithm, Link Aware-NICE (LA-NICE [1], is an enhanced version of the NICE protocol [2]. LA-NICE protocol uses the variations of bandwidth or capacity in communication links to improve multicast message delivery and minimize end-to-end delay. OMNeT++ simulation frame work [3] was used to evaluate LA-NICE. The evaluation is done through a comparison between LA-NICE and NICE. The simulation results showed that LA-NICE produces an increased percentage of success ful message delivery ranging from 2% to 10% compared to NICE. Also, LA-NICE has less average delay and less average message hop count than NICE which reduces the overall latency of message delivery.

  6. An Economic Case for End System Multicast

    Science.gov (United States)

    Analoui, Morteza; Rezvani, Mohammad Hossein

    This paper presents a non-strategic model for the end-system multicast networks based on the concept of replica exchange economy. We believe that microeconomics is a good candidate to investigate the problem of selfishness of the end-users (peers) in order to maximize the aggregate throughput. In this solution concept, the decisions that a peer might make, does not affect the actions of the other peers at all. The proposed mechanism tunes the price of the service in such a way that general equilibrium holds.

  7. A multicast dynamic wavelength assignment algorithm based on matching degree

    Institute of Scientific and Technical Information of China (English)

    WU Qi-wu; ZHOU Xian-wei; WANG Jian-ping; YIN Zhi-hong; ZHANG Long

    2009-01-01

    The wavelength assignment with multiple multicast requests in fixed routing WDM network is studied. A new multicast dynamic wavelength assignment algorithm is presented based on matching degree. First, the wavelength matching degree between available wavelengths and multicast routing trees is introduced into the algorithm. Then, the wavelength assign-ment is translated into the maximum weight matching in bipartite graph, and this matching problem is solved by using an extended Kuhn-Munkres algorithm. The simulation results prove that the overall optimal wavelength assignment scheme is obtained in polynomial time. At the same time, the proposed algorithm can reduce the connecting blocking probability and improve the system resource utilization.

  8. Cooperative relay-based multicasting for energy and delay minimization

    KAUST Repository

    Atat, Rachad

    2012-08-01

    Relay-based multicasting for the purpose of cooperative content distribution is studied. Optimized relay selection is performed with the objective of minimizing the energy consumption or the content distribution delay within a cluster of cooperating mobiles. Two schemes are investigated. The first consists of the BS sending the data only to the relay, and the second scheme considers the scenario of threshold-based multicasting by the BS, where a relay is selected to transmit the data to the mobiles that were not able to receive the multicast data. Both schemes show significant superiority compared to the non-cooperative scenarios, in terms of energy consumption and delay reduction. © 2012 IEEE.

  9. Application of Multicasting in Surveillance Systems%多播在数字监控系统中的应用

    Institute of Scientific and Technical Information of China (English)

    苏士美; 李海芳

    2003-01-01

    This paper discusses problems of multicasting and its application. Two ways are proposed to overcome theproblems of multicasting according to the architectures of current networks and the functional requirements of asurveillance System. One is that Winsock API is directly used to implement multicasting on a network supportingmulticasting. The other adopts the technology of proxy server and tunneling on a network not supporting multicast-ing. In addition,this paper discusses some techniques of multicasting,such as sending,resending,auto-adjusting withthe change of the transmission quality of networks,and the management of multicast group and multicast addresses.

  10. Milestones in Broadcasting: Antennas.

    Science.gov (United States)

    Media in Education and Development, 1985

    1985-01-01

    Briefly describes the development of antennas in the prebroadcast era (elevated antenna, selectivity to prevent interference between stations, birth of diplex, directional properties, support structures), as well as technological developments used in long-, medium-, and short-wave broadcasting, VHF/FM and television broadcasting, and satellite…

  11. Educational Broadcasting--Radio.

    Science.gov (United States)

    Ahamed, Uvais; Grimmett, George

    This manual is intended for those who must conduct educational radio broadcasting training courses in Asia-Pacific countries without the resources of experienced personnel, as well as for individuals to use in self-learning situations. The selection of material has been influenced by the need to use broadcasting resources effectively in programs…

  12. ATM: The Key To Harnessing the Power of Networked Multimedia.

    Science.gov (United States)

    Gross, Rod

    1996-01-01

    ATM (Asynchronous Transfer Mode) network technology handles the real-time continuous traffic flow necessary to support desktop multimedia applications. Describes network applications already used: desktop video collaboration, distance learning, and broadcasting video delivery. Examines the architecture of ATM technology, video delivery and sound…

  13. A Novel Approach for Core Selection in Shared Tree Multicasting

    Directory of Open Access Journals (Sweden)

    Bidyut Gupta

    2014-03-01

    Full Text Available Multicasting is preferred over multiple unicasts from the viewpoint of better utilization of network bandwidth. Multicasting can be done in two different ways: source based tree approach and shared tree approach. Protocols such as Core Based Tree (CBT, Protocol Independent Multicasting Sparse Mode (PIM-SM use shared treeapproach. Shared tree approach is preferred over source-based tree approach because in the later construction of minimum cost treeper source is needed unlike a single shared tree in the former approach.The work presented in this paper provides an efficient core selection method for shared tree multicasting. In this work, we have used a new concept known as pseudo diameter for core selection. The presented methodselects more than one core to achieve fault tolerance

  14. Efficient Resource Management for Multicast Ad Hoc Networks: Survey

    Directory of Open Access Journals (Sweden)

    Amit Chopra

    2016-09-01

    Full Text Available Group communication over multicast ad hoc network suffers from insufficient utilization of limited resources, i.e. shared channel, battery, data processing capabilities and storage space etc. Multicast routing protocol should be able to manage all these resources because their consumption depends upon different factors, i.e. Unicast/Multicast network operations, dynamic topology due to mobility, control overhead due to scalability, packet loss and retransmission due to collision and congestion etc. All these factors may cause unnecessary network load, delay and unfair resource utilization. However, multicast ad hoc routing protocols are more efficient than Unicast routing protocols, but they also suffer from performance degradation factors discussed above. Researchers have developed various layer wise solutions for resource optimization. In this paper, we will explore the different schemes for fair utilization of network resources.

  15. Mobile Multicast in Hierarchical Proxy Mobile IPV6

    Science.gov (United States)

    Hafizah Mohd Aman, Azana; Hashim, Aisha Hassan A.; Mustafa, Amin; Abdullah, Khaizuran

    2013-12-01

    Mobile Internet Protocol Version 6 (MIPv6) environments have been developing very rapidly. Many challenges arise with the fast progress of MIPv6 technologies and its environment. Therefore the importance of improving the existing architecture and operations increases. One of the many challenges which need to be addressed is the need for performance improvement to support mobile multicast. Numerous approaches have been proposed to improve mobile multicast performance. This includes Context Transfer Protocol (CXTP), Hierarchical Mobile IPv6 (HMIPv6), Fast Mobile IPv6 (FMIPv6) and Proxy Mobile IPv6 (PMIPv6). This document describes multicast context transfer in hierarchical proxy mobile IPv6 (H-PMIPv6) to provide better multicasting performance in PMIPv6 domain.

  16. A Proactive Tree Recovery Mechanism for Resilient Overlay Multicast

    Directory of Open Access Journals (Sweden)

    Poorna Satyanarayana B.

    2012-06-01

    Full Text Available Overlay multicast constructs a multicast delivery tree among end hosts. An important problem for making overlay multicast more dependable is how to recover from node departures in order to minimize the disruption of service to those affected nodes. In this paper, we propose a proactive tree recovery mechanism to make the overlay multicast resilient to these failures and unexpected events. The salient feature of the approach is that rescue plans for multiple non-leaf nodes can work together for their respective children when they fail or leave at the same time. Extensive simulations demonstrate that our proactive approach can recover from node departures much faster than reactive methods, while the quality of trees restored and the cost of recovery are reasonable

  17. SPHERE: a scalable multicast framework in overlay networks

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper presents Sphere, a scalable multicast framework in overlay network. Sphere is a highly efficient, self-organizing and robust multicast protocol overlayed on the Internet. The main contributions of this paper are twofold. First, Sphere organizes the control topology of overlay network in two directions: horizontal and vertical. The horizontal meshes are used to locate and organize hosts in tracks, and the vertical meshes are used to manage the data paths between tracks. Second, Sphere balances stress and stretch of the overlay network by assigning hosts into different tracks and clusters. This structure distributes stress on the multicast trees uniformly, and meantime makes path stretch as small as possible.Simulations results show that Sphere can support multicast with large group size and has good performance on organizing meshes and building data delivery trees.

  18. Secure Group Communications for Large Dynamic Multicast Group

    Institute of Scientific and Technical Information of China (English)

    Liu Jing; Zhou Mingtian

    2003-01-01

    As the major problem in multicast security, the group key management has been the focus of research But few results are satisfactory. In this paper, the problems of group key management and access control for large dynamic multicast group have been researched and a solution based on SubGroup Secure Controllers (SGSCs) is presented, which solves many problems in IOLUS system and WGL scheme.

  19. Merging Network Coding with Feedback Management in Multicast Streaming

    DEFF Research Database (Denmark)

    Moreira, André; Almeida, Luis; Roetter, Daniel Enrique Lucani

    2015-01-01

    Reliable multicast over wireless poses interesting challenges arising from the unreliable nature of the wireless medium. Recovering lost packets is particularly challenging in multicast scenarios since different receivers lose different packets. For this reason, simply retransmitting packets does......-case delay as required for QoS sensitive applications. We show preliminary simulation results that confirm the bounded decoding delay of our approach in a streaming application....

  20. Key Management for Secure Multicast over IPv6 Wireless Networks

    Directory of Open Access Journals (Sweden)

    Siddiqi Mohammad Umar

    2006-01-01

    Full Text Available Multicasting is an efficient method for transmission and routing of packets to multiple destinations using fewer network resources. Along with widespread deployment of wireless networks, secure multicast over wireless networks is an important and challenging goal. In this paper, we extend the scope of a recent new key distribution scheme to a security framework that offers a novel solution for secure multicast over IPv6 wireless networks. Our key management framework includes two scenarios for securely distributing the group key and rekey messages for joining and leaving a mobile host in secure multicast group. In addition, we perform the security analysis and provide performance comparisons between our approach and two recently published scenarios. The benefits of our proposed techniques are that they minimize the number of transmissions required to rekey the multicast group and impose minimal storage requirements on the multicast group. In addition, our proposed schemes are also very desirable from the viewpoint of transmission bandwidth savings since an efficient rekeying mechanism is provided for membership changes and they significantly reduce the required bandwidth due to key updating in mobile networks. Moreover, they achieve the security and scalability requirements in wireless networks.

  1. Towards the Capacity Region of Multiplicative Linear Operator Broadcast Channels

    CERN Document Server

    Pang, Yimin

    2010-01-01

    Recent research indicates that packet multicasting employing random linear network coding can be regarded as transmitting subspaces as codewords over a linear operator channel (LOC). A LOC is normally viewed as a discrete memoryless unicast subspace channel over a finite field. In this paper we propose the framework of linear operator broadcast channels (LOBCs) and start initial work on determining their capacity region. LOBC correspond to a single-source multiple-recipients network, where every recipient's subchannel is a LOC having its own capacity. Our discussion concerns a class of constant-dimension multiplicative LOBCs (CMLOBCs), whose input subspaces have constant dimension and missing vectors of a subspace constitute the only possible channel interference. We first give a necessary and sufficient condition for a CMLOBC being stochastically degraded. Then we classify weakly and strongly degraded CMLOBCs. By numerically computing capacity regions with an Arimoto-Blahut type algorithm and discussing seve...

  2. Implications of Internet on Broadcasting

    DEFF Research Database (Denmark)

    Henten, Anders; Tadayoni, Reza

    One of the main challenges within broadcasting research in the recent years has been to understand the evolution from traditional broadcasting to digital broadcasting. The aim of this paper is to step further and give an analysis of Internet’s influence on traditional broadcasting services...

  3. Flexible Broadcasting of Scalable Video Streams in Broadband Wireless System

    Directory of Open Access Journals (Sweden)

    D. Lavanya

    2015-02-01

    Full Text Available This paper presents a novel cross-layer optimization framework to improve the quality of user experience (QOE and energy efficiency of the heterogeneous wireless multimedia broadcast receivers. User grouping is based on the respective UE resolution capabilities and received SNR. A UE capability is determined by the BS at the time of service subscription, when the UE sends its type information, i.e., the number of layers it wants to receive. The UE periodically updated its channel condition to the BS through the uplink channel. This joint optimization is achieved by grouping the users based on their device capabilities and estimated channel conditions experienced by them and broadcasting adaptive content to these groups. The adaptive multimedia content is obtained by using scalable video coding (SVC with optimal source encoding parameters resulted from an innovative cooperative game. Energy saving at user terminals results from using a layer-aware time slicing approach in the transmission stage. Time slicing approach allows discontinuous reception at the UEs, thereby facilitating the UE to turn-off the radio when not receiving data bursts and hence saving energy. A trade-off between energy saving and QOE is observed, and is incorporated in the definition of a utility function of the players in the formulated heterogeneous user composition and physical channel aware game. An adaptive modulation and coding scheme is also optimally incorporated in order to maximize the reception quality of the broadcast receivers, while maximizing the network broadcast capacity.

  4. Multimedia storytelling

    Science.gov (United States)

    Linder, C. A.; Wilbert, M.; Holmes, R. M.

    2010-12-01

    Multimedia video presentations, which integrate still photographs with video clips, audio interviews, ambient sounds, and music, are an effective and engaging way to tell science stories. In July 2009, Linder joined professors and undergraduates on an expedition to the Kolyma River in northeastern Siberia. This IPY science project, called The Polaris Project (http://www.thepolarisproject.org), is an undergraduate research experience where students and faculty work together to increase our understanding of climate change impacts, including thawing permafrost, in this remote corner of the world. During the summer field season, Linder conducted dozens of interviews, captured over 20,000 still photographs and hours of ambient audio and video clips. Following the 2009 expedition, Linder blended this massive archive of visual and audio information into a 10-minute overview video and five student vignettes. In 2010, Linder again traveled to Siberia as part of the Polaris Project, this time mentoring an environmental journalism student who will lead the production of a video about the 2010 field season. Using examples from the Polaris productions, we will present tips, tools, and techniques for creating compelling multimedia science stories.

  5. Financing Public Service Broadcasting

    DEFF Research Database (Denmark)

    Berg, Christian Edelvold; Lund, Anker Brink

    2012-01-01

    Broadcasting (PSB) financing regimes in Europe, concluding that Denmark, Finland, Iceland, Norway, and Sweden may still be considered conventional, licence fee PSB countries, but with some interesting differences in relation to competitive and market oriented alternatives of resource provision...

  6. Network coding for multi-resolution multicast

    DEFF Research Database (Denmark)

    2013-01-01

    A method, apparatus and computer program product for utilizing network coding for multi-resolution multicast is presented. A network source partitions source content into a base layer and one or more refinement layers. The network source receives a respective one or more push-back messages from one...... or more network destination receivers, the push-back messages identifying the one or more refinement layers suited for each one of the one or more network destination receivers. The network source computes a network code involving the base layer and the one or more refinement layers for at least one...... of the one or more network destination receivers, and transmits the network code to the one or more network destination receivers in accordance with the push-back messages....

  7. Multicast Protocol for Uni-Directional Networks

    Institute of Scientific and Technical Information of China (English)

    黄皓; 陈贵海; 谢立; 孙钟秀

    2000-01-01

    A very inexpensive receive-only satellite receiver can receive high bandwidth traffic from a feeder. Therefore the connection between the feeder and the receiver is uni-directional. The existing routing protocols, such as Link-State and Distance-Vector, are designed on the premise that any links are bidirectional and they cannot handle the uni-directional links. In this paper, a dynamic multicast routing protocol is proposed, which can handle uni-directional networks. This protocol can also adapt to the dynamic change of the topology of the network and has good scalability. A formal description of the protocol by Petri net is given. Liveness,deadlock free and other properties of the protocol are proved.

  8. Multicast Routing Based on Hybrid Genetic Algorithm

    Institute of Scientific and Technical Information of China (English)

    CAO Yuan-da; CAI Gui

    2005-01-01

    A new multicast routing algorithm based on the hybrid genetic algorithm (HGA) is proposed. The coding pattern based on the number of routing paths is used. A fitness function that is computed easily and makes algorithm quickly convergent is proposed. A new approach that defines the HGA's parameters is provided. The simulation shows that the approach can increase largely the convergent ratio, and the fitting values of the parameters of this algorithm are different from that of the original algorithms. The optimal mutation probability of HGA equals 0.50 in HGA in the experiment, but that equals 0.07 in SGA. It has been concluded that the population size has a significant influence on the HGA's convergent ratio when it's mutation probability is bigger. The algorithm with a small population size has a high average convergent rate. The population size has little influence on HGA with the lower mutation probability.

  9. Protocol Independent Multicast Based States Allocation

    Directory of Open Access Journals (Sweden)

    G Hemalatha

    2012-02-01

    Full Text Available In this paper the Protocol Independent Multicast (PIM protocol is being used. The PIM protocol avoids the packet drop and diverting problem. The PIM protocol is not dependent on any specific unicast routing protocol. It is IP routing independent protocol. The PIM uses the unicast and multicast information to create a distribution tree along the reverse path from the receivers towards the source. The PIM protocol consists of three modes such as sparse mode, dense mode and bidirectional mode. The sparse mode is used to sends the file from router to a receiver. The dense mode is used to sends the file from router to multiple receivers. The bidirectional mode is used to sends the message from router to sender and then continue the other process depending on the sender requirements. The client sends the file from sender to destination via the router. First the sender selects the file name and receiver name for transmission. Then the state is assigned automatically depend upon the user selection. The state can be defined by the number of destination selected to transmit the file from the source. If the sender selects single destination, it will assign “Without forwarding state router” for transmission. Otherwise it will assign “Forwarding state router” for transmission. If the receiver is not available, the router sends a message to sender such that “the requested receiver is not available”. Then the client will decide the file is transfer or not, it will reply with transfer the file, then the file will be transferred until the file will be discarded at client side. If the sender tries the same process after two times, the router will display the warning message as “the requested receiver is not available, this file will be discarded at client side”. Then it continues the other process.

  10. Broadcasters Hit Home Straight

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    China’s broadcasters enter the final phase of preparations fbr next year’s Olympic Games The most critical information we are keen on delivering is that every- thing is going well,said Sun Weijia, Director of the Media Operations Department of the Beijing Organizing Committee for the Games of of the XXIX Olympiad(BOCOG)on the eve of the 2007 World Broadcasters Conference.

  11. Cost-Effective and Fast Handoff Scheme in Proxy Mobile IPv6 Networks with Multicasting Support

    Directory of Open Access Journals (Sweden)

    Illkyun Im

    2014-01-01

    Full Text Available With recent advancements in wireless communication technologies, mobile multicasting is becoming important, in an effort to use network resources more efficiently. In the past, when various mobile IP-based multicast techniques were proposed, the focus was on the costs needed for network delivery to provide multicast services, as well as on minimizing the multicast handover delay. However, it is fundamentally difficult to resolve the problems of handover delay and tunnel convergence for techniques using MIPv6 (Mobile IPv6, a host-based mobility management protocol. To resolve these problems, the network-based mobility management protocol PMIPv6 (Proxy Mobile IPv6 was standardized. Although performance is improved in PMIPv6 over MIPv6, it still suffers from problems of handover delay and tunnel convergence. To overcome these limitations, a technique called LFH (Low-cost and Fast Handoff is proposed in this paper, for fast and low-cost mobility management with multicasting support in PMIPv6 networks. To reduce the interactions between the complex multicast routing protocol and multicast messages, a simplified proxy method called MLD (Multicast Listener Discovery is implemented and modified. Furthermore, a TCR (Tunnel Combination and Reconstruction algorithm was used in the multicast handover procedure within the LMA (Local Mobility Anchor domain, as well as in the multicast handover procedure between domains, in order to overcome the problem of tunnel convergence. It was found that, compared to other types of multicast techniques, LFH reduces multicast delay, and requires lower cost.

  12. Hadamard quantum broadcast channels

    Science.gov (United States)

    Wang, Qingle; Das, Siddhartha; Wilde, Mark M.

    2017-10-01

    We consider three different communication tasks for quantum broadcast channels, and we determine the capacity region of a Hadamard broadcast channel for these various tasks. We define a Hadamard broadcast channel to be such that the channel from the sender to one of the receivers is entanglement-breaking and the channel from the sender to the other receiver is complementary to this one. As such, this channel is a quantum generalization of a degraded broadcast channel, which is well known in classical information theory. The first communication task we consider is classical communication to both receivers, the second is quantum communication to the stronger receiver and classical communication to other, and the third is entanglement-assisted classical communication to the stronger receiver and unassisted classical communication to the other. The structure of a Hadamard broadcast channel plays a critical role in our analysis: The channel to the weaker receiver can be simulated by performing a measurement channel on the stronger receiver's system, followed by a preparation channel. As such, we can incorporate the classical output of the measurement channel as an auxiliary variable and solve all three of the above capacities for Hadamard broadcast channels, in this way avoiding known difficulties associated with quantum auxiliary variables.

  13. A Mobility-aware Broadcasting Infrastructure for a Wireless Internet with Hotspots

    NARCIS (Netherlands)

    Hesselman, Cristian; Eertink, Henk; Widya, Ing; Huizer, Erik; Kermani, P.

    2003-01-01

    In this paper, we consider the problem of adaptively delivering live multimedia broadcasts (e.g., for applications such as TV, radio, or e-cinema) to a potentially large number of mobile hosts that roam about in a wireless internet with hotspots. We take a user-oriented approach based on an applicat

  14. Performance analysis of optical multicast in a new switching structure

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The emergence of new services demands multicast function in optical network.Because of the high cost and complex architecture of multicast capable (MC) node, splitter-sharing switch structure is introduced in which the light splitters are shared by all input signals.To accommodate to this situation, by extending resource ReSerVation protocol-traffic engineering (RSVP-TE) and open shortest path first-traffic engineering (OSPF-TE), a new optical multicast mechanism is provided and the signaling flow and its finite state machine model are given.At the same time, a multicast routing algorithm in splitter-sharing optical network and a changing link weight policy to balance network traffic are proposed.Simulations in NSFNET show no matter with or without wavelength converters, when the number of splitters is 25% of that demanded by traditional MC nodes, the multicast performance has been close to the ideal circumstance.Wavelength converters and changing link weight help much in improving the traffic performance when the number of splitters is adequate.

  15. Reliable Multicast Error Recovery Algorithm in Ad-Hoc Networks

    Directory of Open Access Journals (Sweden)

    Tariq Abdullah

    2012-11-01

    Full Text Available Mobile ad hoc network is an autonomous system of mobile nodes characterized by wireless links. The major challenge in ad hoc networks lies in adapting multicast communication to several environments, where mobility is unlimited and failures are frequent. Reliable multicast delivery requires a multicast message to be received by all mobile nodes in the communication group. The recovery mechanism requires feedback messages from each one of the receivers. In the tree-based recovery protocols, a group of nodes into recovery regions designate a forwarding node per region for retransmitting lost messages. In this study, local error recovery algorithm is applied within these relatively smaller regions, where the repaired packets are retransmitted only to the requested receivers in the local group. These receivers create a sub group from the local group which itself is a subgroup of the global multicast group. By applying local error recovery algorithm, the number of duplicated packets, due to packets retransmission, decreases which lead to improving the system performance. Simulation results demonstrate the scalability of the proposed algorithm in comparison to Source Tree Reliable Multicast (STRM protocol. The algorithm achieved up to 2.33% improvement on the percentage of duplicated packets in stable mobility speed without incurring any further communication or intense computation overhead.

  16. Mobility based multicast routing in wireless mesh networks

    Science.gov (United States)

    Jain, Sanjeev; Tripathi, Vijay S.; Tiwari, Sudarshan

    2013-01-01

    There exist two fundamental approaches to multicast routing namely minimum cost trees and shortest path trees. The (MCT's) minimum cost tree is one which connects receiver and sources by providing a minimum number of transmissions (MNTs) the MNTs approach is generally used for energy constraint sensor and mobile ad hoc networks. In this paper we have considered node mobility and try to find out simulation based comparison of the (SPT's) shortest path tree, (MST's) minimum steiner trees and minimum number of transmission trees in wireless mesh networks by using the performance metrics like as an end to end delay, average jitter, throughput and packet delivery ratio, average unicast packet delivery ratio, etc. We have also evaluated multicast performance in the small and large wireless mesh networks. In case of multicast performance in the small networks we have found that when the traffic load is moderate or high the SPTs outperform the MSTs and MNTs in all cases. The SPTs have lowest end to end delay and average jitter in almost all cases. In case of multicast performance in the large network we have seen that the MSTs provide minimum total edge cost and minimum number of transmissions. We have also found that the one drawback of SPTs, when the group size is large and rate of multicast sending is high SPTs causes more packet losses to other flows as MCTs.

  17. Multimedia technologies in education.

    Science.gov (United States)

    Liaskos, Joseph; Diomidus, Marianna

    2002-01-01

    In general multimedia is the combination of visual and audio representations. These representations could include elements of texts, graphic arts, sound, animation, and video. However, multimedia is restricted in such systems where information is digitalized and is processed by a computer. Interactive multimedia and hypermedia consist of multimedia applications that the user has more active role. Education is perhaps the most useful destination for multimedia and the place where multimedia has the most effective applications, as it enriches the learning process. Multimedia both in nursing education and in medical informatics education has several applications as well. A multimedia project can be developed even as a "stand alone" application (on CD-ROM), or on World Wide Web pages on Internet. However several technical constraints exist for developing multimedia applications on Internet. For developing multimedia projects we need hardware and software, talent and skill. The software requirements for multimedia development consist of one or more authoring systems and various editing applications for text, images, sounds and video. In this chapter different software tools for creating multimedia applications are presented. In the last part of this chapter, two examples of multimedia educational training programs are discussed. Both are "stand alone" applications (CD-ROMs). The first, examines several aspects of the electronic patient record by using videos, audio descriptions, lectures and glossary, while the second one presents several topics regarding epidemiology and epidemiological research by using graphics, sound and animation.

  18. 47 CFR 1.4000 - Restrictions impairing reception of television broadcast signals, direct broadcast satellite...

    Science.gov (United States)

    2010-10-01

    ... broadcast signals, direct broadcast satellite services or multichannel multipoint distribution services. 1... Broadcast Satellite Services, or Multichannel Multipoint Distribution Services or the Ability To Receive or... broadcast signals, direct broadcast satellite services or multichannel multipoint distribution services....

  19. A SURVEY ON MULTICAST ROUTING PROTOCOLS FOR PERFORMANCE EVALUATION IN WIRELESS SENSOR NETWORK

    Directory of Open Access Journals (Sweden)

    A. Suruliandi

    2015-03-01

    Full Text Available Multicast is a process used to transfer same message to multiple receivers at the same time. This paper presents the simulation and analysis of the performance of six different multicast routing protocols for Wireless Sensor Network (WSN. They are On Demand Multicast Routing Protocol (ODMRP, Protocol for Unified Multicasting through Announcement (PUMA, Multicast Adhoc On demand Distance Vector Protocol (MAODV, Overlay Boruvka-based Adhoc Multicast Protocol (OBAMP, Application Layer Multicast Algorithm (ALMA and enhanced version of ALMA (ALMA-H for WSN. Among them, ODMRP, MAODV and PUMA are reactive protocols while OBAMP, ALMA and ALMA-H are proactive protocols. This paper compares the performance of these protocols with common parameters such as Throughput, Reliability, End-to-End delay and Packet Delivery Ratio (PDR with increasing the numbers of nodes and increasing the speed of the nodes. The main objective of this work is to select the efficient multicast routing protocol for WSN among six multicast routing protocol based on relative strength and weakness of each protocol. The summary of above six multicast routing protocols is presented with a table of different performance characteristics. Experimental result shows that ODMRP attains higher throughput, reliability and higher packet delivery ratio than other multicast routing protocol, while incurring far less end-to-end delay.

  20. The Special Broadcasting Service and Australia's Ethnic Broadcasting Activities.

    Science.gov (United States)

    Sklovsky, G.A.

    1979-01-01

    Broadcasting services for non-English speaking peoples in Australia are reviewed both for radio and television. Broadcasting criteria for ethnic groups, funding levels, and current facilities are discussed. (RAO)

  1. Multicast Address Management and Connection Control Based on Hierarchical Autonomous Structure

    Institute of Scientific and Technical Information of China (English)

    WANG Jian; ZHANG Fuyan

    1999-01-01

    Multicast capability, including multicast address and multicast routing mechanisms, at the network layeris necessary in order to reduce the bandwidth requirements of multiparty, multicast applications. Based on hierarchical autonomous structure in accordance with the self-organization topologies of Internet, the paper puts forward a multicast address management scheme that is shown to be robust and scalable. Connection control hierarchy (CCH) based on master/slave relationship and a simple efficient building algorithm of multi-point connection is also built. The paper also describes the normal operations of multicast address management andmulti-point connection controller. Through simulation experiment, HAM, CM and DDM of Multicast Address Allocation are compared. HAM integrates the merits of CM and DDM, which is efficient as a whole, robust andscalable. CCH raises the efficiency of connection control, and is highly robust, flexible and scalable.

  2. Multicasting along Energy—Efficient Meshes in Mobile Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    JIANGHai; CHENGShixin; HEYongming

    2003-01-01

    In consideration that current mesh-based multicast routing protocols for mobile ad hoc networks don't tend to form energy-efficient multicast infrastruc-ture, we propose a new Energy-efficient multicast rout-ing protocol (E2MRP) for mobile ad hoc networks. The two main characteristics of E2MRP are: (1) using in turn the criteria for minimum energy consumed per packet and minimum maximum node cost during the course of relaying group (RG) creation and maintenance; (2)forming a graph-based multicast infrastructure instead of a tree-based one. Compared to multicast incremen-tal power (MIP) and on-demand multicast routing pro-tocol (ODMRP), as the simulation results show, E2MRP tremendously reduces the energy consumption rate of nodes and hence prolongs the lifetime of nodes and net-works, especially when the size of multicast group is small and node mobility is low.

  3. Reliable multicast for the Grid: a case study in experimental computer science.

    Science.gov (United States)

    Nekovee, Maziar; Barcellos, Marinho P; Daw, Michael

    2005-08-15

    In its simplest form, multicast communication is the process of sending data packets from a source to multiple destinations in the same logical multicast group. IP multicast allows the efficient transport of data through wide-area networks, and its potentially great value for the Grid has been highlighted recently by a number of research groups. In this paper, we focus on the use of IP multicast in Grid applications, which require high-throughput reliable multicast. These include Grid-enabled computational steering and collaborative visualization applications, and wide-area distributed computing. We describe the results of our extensive evaluation studies of state-of-the-art reliable-multicast protocols, which were performed on the UK's high-speed academic networks. Based on these studies, we examine the ability of current reliable multicast technology to meet the Grid's requirements and discuss future directions.

  4. A Novel OBDD-Based Reliability Evaluation Algorithm for Wireless Sensor Networks on the Multicast Model

    Directory of Open Access Journals (Sweden)

    Zongshuai Yan

    2015-01-01

    Full Text Available The two-terminal reliability calculation for wireless sensor networks (WSNs is a #P-hard problem. The reliability calculation of WSNs on the multicast model provides an even worse combinatorial explosion of node states with respect to the calculation of WSNs on the unicast model; many real WSNs require the multicast model to deliver information. This research first provides a formal definition for the WSN on the multicast model. Next, a symbolic OBDD_Multicast algorithm is proposed to evaluate the reliability of WSNs on the multicast model. Furthermore, our research on OBDD_Multicast construction avoids the problem of invalid expansion, which reduces the number of subnetworks by identifying the redundant paths of two adjacent nodes and s-t unconnected paths. Experiments show that the OBDD_Multicast both reduces the complexity of the WSN reliability analysis and has a lower running time than Xing’s OBDD- (ordered binary decision diagram- based algorithm.

  5. Performance Evaluation of Unicast and Broadcast Mobile Ad hoc Network Routing Protocols

    CERN Document Server

    Debnath, Sumon Kumar; Islam, Nayeema

    2010-01-01

    Efficient routing mechanism is a challenging issue for group oriented computing in Mobile Ad Hoc Networks (MANETs). The ability of MANETs to support adequate Quality of Service (QoS) for group communication is limited by the ability of the underlying ad-hoc routing protocols to provide consistent behavior despite the dynamic properties of mobile computing devices. In MANET QoS requirements can be quantified in terms of Packet Delivery Ratio (PDR), Data Latency, Packet Loss Probability, Routing Overhead, Medium Access Control (MAC) Overhead and Data Throughput etc. This paper presents an in depth study of one to many and many to many communications in MANETs and provides a comparative performance evaluation of unicast and broadcast routing protocols. Dynamic Source Routing protocol (DSR) is used as unicast protocol and BCAST is used to represent broadcast protocol. The performance differentials are analyzed using ns2 network simulator varying multicast group size (number of data senders and data receivers). Bo...

  6. Quantum broadcast scheme and multi-output quantum teleportation via four-qubit cluster state

    Science.gov (United States)

    Yu, Yan; Zha, Xin Wei; Li, Wei

    2017-02-01

    In this paper, two theoretical schemes of the arbitrary single-qubit states via four-qubit cluster state are proposed. One is three-party quantum broadcast scheme, which realizes the broadcast among three participants. The other is multi-output quantum teleportation. Both allow two distant receivers to simultaneously and deterministically obtain the arbitrary single-qubit states, respectively. Compared with former schemes of an arbitrary single-qubit state, the proposed schemes realize quantum multi-cast communication efficiently, which enables Bob and Charlie to obtain the states simultaneously in the case of just knowing Alice's measurement results. The proposed schemes play an important role in quantum information, specially in secret sharing and quantum teleportation.

  7. Effectief leren van multimedia

    NARCIS (Netherlands)

    Kester, Liesbeth

    2013-01-01

    Kester, L. (2012, March). Effectief leren van multimedia [Effective learning from multimedia]. Keynote presented at a miniconference Learning Sciences of the Open University of the Netherlands, Eindhoven, the Netherlands.

  8. Effectief leren van multimedia

    NARCIS (Netherlands)

    Kester, Liesbeth

    2013-01-01

    Kester, L. (2012, March). Effectief leren van multimedia [Effective learning from multimedia]. Keynote presented at a miniconference Learning Sciences of the Open University of the Netherlands, Eindhoven, the Netherlands.

  9. Reformative multicast routing protocol based on Ad Hoc

    Institute of Scientific and Technical Information of China (English)

    杨喜旺; 王华; 焦国太

    2008-01-01

    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.

  10. Efficient Non-Repudiation Multicast Source Authentication Schemes

    Institute of Scientific and Technical Information of China (English)

    李先贤; 怀进鹏

    2002-01-01

    In secure multicast communication, packet source authentication is a bot-tleneck problem due to the dynamic property of the multicast group, unreliability of datatransmission and the large number of data packets. This paper proposes a novel authentica-tion scheme called B-MSAS (Balance Multicast Source Authentication Scheme) that can beused to solve this problem, in which a new message authentication technique is introduced.This scheme dramatically reduces the signature size overhead and raises the signature rate. Itprovides the non-repudiation service, high loss resistance, and can easily be scaled up to poten-tially millions of receivers, and hence has a sweeping applicability. It should have applicationsto many practical problems.

  11. Algorithm for Delay-Constrained Minimal Cost Group Multicasting

    Institute of Scientific and Technical Information of China (English)

    SUN Yugeng; WANG Yanlin; YAN Xinfang

    2005-01-01

    Group multicast routing algorithms satisfying quality of service requirements of real-time applications are essential for high-speed networks. A heuristic algorithm was presented for group multicast routing with bandwidth and delay constrained. A new metric was designed as a function of available bandwidth and delay of link. And source-specific routing trees for each member were generated in the algorithm by using the metric, which satisfy member′s bandwidth and end-to-end delay requirements. Simulations over random network were carried out to compare the performance of the proposed algorithm with that from literature.Experimental results show that the algorithm performs better in terms of network cost and ability in constructing feasible multicast trees for group members. Moreover,the algorithm can avoid link blocking and enhance the network behavior efficiently.

  12. A History of Multimedia.

    Science.gov (United States)

    Burke, Larry Kenneth

    The history of multimedia and descriptions of various multimedia events from 1900 to 1972 are presented. The development of multimedia events is described for four eras and four main classifications of events: multiscreen presentations, electronic media and performers, environmental theater, and environments. Five appendixes include a discussion…

  13. Multimedia Authoring and Annotation

    NARCIS (Netherlands)

    Bulterman, D.C.A.; Cesar Garcia, P.S.; Munson, E.; Pimentel, M.G.C.

    2014-01-01

    With the massive amount of captured multimedia, authoring is more relevant than ever. Multimedia content is available in many settings including the web, mobile devices, desktop applications, as well as games and interactive TV. The authoring and production of multimedia documents demands attention

  14. Overlay Multicast Networks : Elements, Architectures and Performance

    OpenAIRE

    Constantinescu, Doru

    2007-01-01

    Today, the telecommunication industry is undergoing two important developments with implications on future architectural solutions. These are the irreversible move towards Internet Protocol (IP)-based networking and the deployment of broadband access. Taken together, these developments offer the opportunity for more advanced and more bandwidth-demanding multimedia applications and services, e. g., IP television (IPTV), Voice over IP (VoIP) and online gaming. A plethora of Quality of Service (...

  15. Application layer multicast routing solution based on genetic algorithms

    Institute of Scientific and Technical Information of China (English)

    Peng CHENG; Qiufeng WU; Qionghai DAI

    2009-01-01

    Application layer multicast routing is a multi-objective optimization problem.Three routing con-straints,tree's cost,tree's balance and network layer load distribution are analyzed in this paper.The three fitness functions are used to evaluate a multicast tree on the three indexes respectively and one general fitness function is generated.A novel approach based on genetic algorithms is proposed.Numerical simulations show that,compared with geometrical routing rules,the proposed algorithm improve all three indexes,especially on cost and network layer load distribution indexes.

  16. QUANTIFIED COST-BALANCED ROUTING SCHEME FOR OVERLAY MULTICAST

    Institute of Scientific and Technical Information of China (English)

    Lu Jun; Ruan Qiuqi

    2006-01-01

    This paper focuses on the quantitative analysis issue of the routing metrics tradeoff problem, and presents a Quantified Cost-Balanced overlay multicast routing scheme (QCost-Balanced) to the metric tradeoff problem between overlay path delay and access bandwidth at Multicast Server Nodes (MSN) for real-time applications over Internet. Besides implementing a dynamic priority to MSNs by weighing the size of its service clients for better efficiency, QCost-Balanced tradeoffs these two metrics by a unified tradeoff metric based on quantitative analysis. Simulation experiments demonstrate that the scheme achieves a better tradeoff gain in both two metrics, and effective performance in metric quantitative control.

  17. Optimization of multicast optical networks with genetic algorithm

    Science.gov (United States)

    Lv, Bo; Mao, Xiangqiao; Zhang, Feng; Qin, Xi; Lu, Dan; Chen, Ming; Chen, Yong; Cao, Jihong; Jian, Shuisheng

    2007-11-01

    In this letter, aiming to obtain the best multicast performance of optical network in which the video conference information is carried by specified wavelength, we extend the solutions of matrix games with the network coding theory and devise a new method to solve the complex problems of multicast network switching. In addition, an experimental optical network has been testified with best switching strategies by employing the novel numerical solution designed with an effective way of genetic algorithm. The result shows that optimal solutions with genetic algorithm are accordance with the ones with the traditional fictitious play method.

  18. Empirical Evaluation of Superposition Coded Multicasting for Scalable Video

    KAUST Repository

    Chun Pong Lau

    2013-03-01

    In this paper we investigate cross-layer superposition coded multicast (SCM). Previous studies have proven its effectiveness in exploiting better channel capacity and service granularities via both analytical and simulation approaches. However, it has never been practically implemented using a commercial 4G system. This paper demonstrates our prototype in achieving the SCM using a standard 802.16 based testbed for scalable video transmissions. In particular, to implement the superposition coded (SPC) modulation, we take advantage a novel software approach, namely logical SPC (L-SPC), which aims to mimic the physical layer superposition coded modulation. The emulation results show improved throughput comparing with generic multicast method.

  19. Design of an IPTV Multicast System for Internet Backbone Networks

    OpenAIRE

    T. H. Szymanski; Gilbert, D

    2010-01-01

    The design of an IPTV multicast system for the Internet backbone network is presented and explored through extensive simulations. In the proposed system, a resource reservation algorithm such as RSVP, IntServ, or DiffServ is used to reserve resources (i.e., bandwidth and buffer space) in each router in an IP multicast tree. Each router uses an Input-Queued, Output-Queued, or Crosspoint-Queued switch architecture with unity speedup. A recently proposed Recursive Fair Stochastic Matrix Decompos...

  20. Unified broadcast in sensor networks

    DEFF Research Database (Denmark)

    Hansen, Morten Tranberg; Jurdak, Raja; Kusy, Branislav

    2011-01-01

    to consolidate these broadcasts focus on piggybacking information into existing services but such tight coupling between protocols limits code reuse and interoperability of applications. We present Unified Broadcast (UB) which combines broadcasts from multiple protocols while maintaining a modular architecture......Complex sensor network applications include multiple services such as collection, dissemination, time synchronization, and failure detection protocols. Many of these protocols require local state maintenance through periodic broadcasts which leads to high control overhead. Recent attempts...

  1. HIGH-BANDWITH MULTICAST IN COOPERATIVE ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    A.Darwin Marks

    2015-10-01

    Full Text Available We study the matter of maximizing the printed rate in peer-to-peer (P2P systems underneath node degree bounds, i.e., the quantity of neighbors a node will at the same time hook up with is upper-bounded. The matter is important for supporting high-quality video streaming in P2P systems and is difficult because of its combinatorial nature. during this paper, we tend to address this drawback by providing the primary distributed answer that achieves near-optimal broadcast rate underneath capricious node degree bounds and over capricious overlay graph. It runs on individual nodes and utilizes solely the measuring from their one-hop neighbors, creating the answer simple to implement and all-mains to see churn and network dynamics. Our answer consists of 2 distributed algorithmic programs planned during this paper which will be of freelance interests: a network-coding-based broadcasting algorithm that optimizes the printed rate given a topology, and a Markov-chain target-hunting topology hopping algorithmic program that optimizes the topology. Our distributed broadcasting algorithmic program achieves the optimum broadcast rate over capricious P2P topology, whereas antecedently planned distributed algorithms get optimality just for P2P complete graphs. We tend to prove the optimality of our answer and its convergence to a district round the optimal equilibrium underneath strident measurements or while not time-scale separation assumptions. we tend to demonstrate the effectiveness of our answer in simulations victimization transmission information measure statistics of web hosts.

  2. Generalized no-broadcasting theorem.

    Science.gov (United States)

    Barnum, Howard; Barrett, Jonathan; Leifer, Matthew; Wilce, Alexander

    2007-12-14

    We prove a generalized version of the no-broadcasting theorem, applicable to essentially any nonclassical finite-dimensional probabilistic model satisfying a no-signaling criterion, including ones with "superquantum" correlations. A strengthened version of the quantum no-broadcasting theorem follows, and its proof is significantly simpler than existing proofs of the no-broadcasting theorem.

  3. ARMrayan Multimedia Mobile CMS: a Simplified Approach towards Content-Oriented Mobile Application Designing

    OpenAIRE

    Manashty, Ali Reza; Raji, Mohammad Reza Ahmadzadeh; Jahromi, Zahra Forootan; Rajabzadeh, Amir

    2010-01-01

    The ARMrayan Multimedia Mobile CMS (Content Management System) is the first mobile CMS that gives the opportunity to users for creating multimedia J2ME mobile applications with their desired content, design and logo; simply, without any need for writing even a line of code. The low-level programming and compatibility problems of the J2ME, along with UI designing difficulties, makes it hard for most people -even programmers- to broadcast their content to the widespread mobile phones used by ne...

  4. From Broadcast to Podcast

    DEFF Research Database (Denmark)

    Fibiger, Bo

    2007-01-01

    This paper will present the development from broadcasted educational television up to the actual use of streaming video and mobile units in eLearning. The paper will discuss the following topics: what can we learn from history? – and what are the new challenges and possibilities in mobile technol...

  5. Restricted broadcast process theory

    NARCIS (Netherlands)

    Ghassemi, F.; Fokkink, W.J.; Movaghar, A.; Cerone, A.; Gruner, S.

    2008-01-01

    We present a process algebra for modeling and reasoning about Mobile Ad hoc Networks (MANETs) and their protocols. In our algebra we model the essential modeling concepts of ad hoc networks, i.e. local broadcast, connectivity of nodes and connectivity changes. Connectivity and connectivity changes a

  6. Virtue Broadcasting - directorate change

    CERN Multimedia

    2003-01-01

    The Board of Virtue Broadcasting Plc ("Virtue") have announced the appointment of Mr. Klaus Ackerstaff as the CEO of the main Board. He began his professional career at CERN, where he was responsible for the IT infrastructure of the OPAL (particle physics) project (1/2 page).

  7. PERANCANGAN DAN IMPLEMENTASI APLIKASI INTERNET RADIO MENGGUNAKAN MULTIMEDIA DATABASE MELALUI PENERAPAN ONTOLOGY DAN METADATA

    Directory of Open Access Journals (Sweden)

    M. Rudy Erwansyah

    2012-05-01

    scheduling, reporting, user and ontology. In the implementation of internet application of this radio, the audio data management uses multimedia database by applying metadata and ontology, so that the process of indexing and retrieval can be reused quickly on the broadcast. This application can also be used in carrying out the radio broadcast automatically during specified hours. This internet radio application has been able to meet the needs of radio Heartline.

  8. Deploying Next Generation Multicast-enabled Applications Label Switched Multicast for MPLS VPNs, VPLS, and Wholesale Ethernet

    CERN Document Server

    Joseph, Vinod

    2011-01-01

    The growth, scale, and prominence of video applications over the years have placed emphasis on the most scalable and efficient way to deliver multi-play content (voice, video and data) to the end user. Multicast is the most effective and efficient carrier of video applications from a network standpoint. Financial organizations deploy large-scale multicast infrastructures to enable trading and e-commerce. The introduction of 4G and beyond makes this technology even more indispensible since mobile operators need an efficient mechanism to deliver repetitive content to many a handset, and multicas

  9. VMCast: A VM-Assisted Stability Enhancing Solution for Tree-Based Overlay Multicast.

    Science.gov (United States)

    Gu, Weidong; Zhang, Xinchang; Gong, Bin; Zhang, Wei; Wang, Lu

    2015-01-01

    Tree-based overlay multicast is an effective group communication method for media streaming applications. However, a group member's departure causes all of its descendants to be disconnected from the multicast tree for some time, which results in poor performance. The above problem is difficult to be addressed because overlay multicast tree is intrinsically instable. In this paper, we proposed a novel stability enhancing solution, VMCast, for tree-based overlay multicast. This solution uses two types of on-demand cloud virtual machines (VMs), i.e., multicast VMs (MVMs) and compensation VMs (CVMs). MVMs are used to disseminate the multicast data, whereas CVMs are used to offer streaming compensation. The used VMs in the same cloud datacenter constitute a VM cluster. Each VM cluster is responsible for a service domain (VMSD), and each group member belongs to a specific VMSD. The data source delivers the multicast data to MVMs through a reliable path, and MVMs further disseminate the data to group members along domain overlay multicast trees. The above approach structurally improves the stability of the overlay multicast tree. We further utilized CVM-based streaming compensation to enhance the stability of the data distribution in the VMSDs. VMCast can be used as an extension to existing tree-based overlay multicast solutions, to provide better services for media streaming applications. We applied VMCast to two application instances (i.e., HMTP and HCcast). The results show that it can obviously enhance the stability of the data distribution.

  10. An Optical Multicast Routing with Minimal Network Coding Operations in WDM Networks

    Directory of Open Access Journals (Sweden)

    Huanlin Liu

    2014-01-01

    Full Text Available Network coding can improve the optical multicast routing performance in terms of network throughput, bandwidth utilization, and traffic load balance. But network coding needs high encoding operations costs in all-optical WDM networks due to shortage of optical RAM. In the paper, the network coding operation is defined to evaluate the number of network coding operation cost in the paper. An optical multicast routing algorithm based on minimal number of network coding operations is proposed to improve the multicast capacity. Two heuristic criteria are designed to establish the multicast routing with low network coding cost and high multicast capacity. One is to select one path from the former K shortest paths with the least probability of dropping the multicast maximal capacity. The other is to select the path with lowest potential coding operations with the highest link shared degree among the multiple wavelength disjoint paths cluster from source to each destination. Comparing with the other multicast routing based on network coding, simulation results show that the proposed multicast routing algorithm can effectively reduce the times of network coding operations, can improve the probability of reaching multicast maximal capacity, and can keep the less multicast routing link cost for optical WDM networks.

  11. VMCast: A VM-Assisted Stability Enhancing Solution for Tree-Based Overlay Multicast.

    Directory of Open Access Journals (Sweden)

    Weidong Gu

    Full Text Available Tree-based overlay multicast is an effective group communication method for media streaming applications. However, a group member's departure causes all of its descendants to be disconnected from the multicast tree for some time, which results in poor performance. The above problem is difficult to be addressed because overlay multicast tree is intrinsically instable. In this paper, we proposed a novel stability enhancing solution, VMCast, for tree-based overlay multicast. This solution uses two types of on-demand cloud virtual machines (VMs, i.e., multicast VMs (MVMs and compensation VMs (CVMs. MVMs are used to disseminate the multicast data, whereas CVMs are used to offer streaming compensation. The used VMs in the same cloud datacenter constitute a VM cluster. Each VM cluster is responsible for a service domain (VMSD, and each group member belongs to a specific VMSD. The data source delivers the multicast data to MVMs through a reliable path, and MVMs further disseminate the data to group members along domain overlay multicast trees. The above approach structurally improves the stability of the overlay multicast tree. We further utilized CVM-based streaming compensation to enhance the stability of the data distribution in the VMSDs. VMCast can be used as an extension to existing tree-based overlay multicast solutions, to provide better services for media streaming applications. We applied VMCast to two application instances (i.e., HMTP and HCcast. The results show that it can obviously enhance the stability of the data distribution.

  12. Performance of QoS-based multicast routing algorithms for real-time communication

    Science.gov (United States)

    Verma, Sanjeev; Pankaj, Rajesh K.; Leon-Garcia, Alberto

    1997-10-01

    In recent years, there has been a lot of interest in providing real-time multimedia services like digital audio and video over packet-switched networks such as Internet and ATM. These services require certain quality of service (QoS) from the network. The routing algorithm should take QoS factor for an application into account while selecting the most suitable route for the application. In this paper, we introduce a new routing metric and use it with two different heuristics to compute the multicast tree for guaranteed QoS applications that need firm end-to-end delay bound. We then compare the performance of our algorithms with the other proposed QoS-based routing algorithms. Simulations were run over a number of random networks to measure the performance of different algorithms. We studied routing algorithms along with resource reservation and admission control to measure the call throughput over a number of random networks. Simulation results show that our algorithms give a much better performance in terms of call throughput over other proposed schemes like QOSPF.

  13. Research of Mobile Multicast Based on Mobile IP%基于移动IP的移动组播技术研究

    Institute of Scientific and Technical Information of China (English)

    张斌; 张汝云; 邬江兴

    2003-01-01

    This paper discusses the method of mobile multicast based on mobile IP protocol proposed by IETF. At first, the paper analyzes the methods of Remote subscription and Home subscription, points out the latent problem in mobile ip protocol,and gives the methods of mobile multicast and multicast agent to solve mobile multicast problem, then compares delivery cost of multicast and delivery delay of multicast packets as well as disruption of multicast service due to mobility in four kinds of methods of mobile multicast.

  14. Lossless Multicast Handovers in Proxy Fast Mobile IPv6 Networks

    NARCIS (Netherlands)

    Meijerink, Bernd; Heijenk, G.J.

    2015-01-01

    There is a demand in the Public Protection and Disaster Relief (PPDR) community for high bandwidth services on mobile devices. Group communication is an important aspect of PPDR networks. In IP based networks multicast is the preferred method to efficiently transmit data to more than one receiver si

  15. Dynamic multicast routing scheme in WDM optical network

    Science.gov (United States)

    Zhu, Yonghua; Dong, Zhiling; Yao, Hong; Yang, Jianyong; Liu, Yibin

    2007-11-01

    During the information era, the Internet and the service of World Wide Web develop rapidly. Therefore, the wider and wider bandwidth is required with the lower and lower cost. The demand of operation turns out to be diversified. Data, images, videos and other special transmission demands share the challenge and opportunity with the service providers. Simultaneously, the electrical equipment has approached their limit. So the optical communication based on the wavelength division multiplexing (WDM) and the optical cross-connects (OXCs) shows great potentials and brilliant future to build an optical network based on the unique technical advantage and multi-wavelength characteristic. In this paper, we propose a multi-layered graph model with inter-path between layers to solve the problem of multicast routing wavelength assignment (RWA) contemporarily by employing an efficient graph theoretic formulation. And at the same time, an efficient dynamic multicast algorithm named Distributed Message Copying Multicast (DMCM) mechanism is also proposed. The multicast tree with minimum hops can be constructed dynamically according to this proposed scheme.

  16. Using Multicast-SNMP to coordinate Distributed Management Agents

    NARCIS (Netherlands)

    Schönwälder, J.

    1996-01-01

    This paper presents a mechanism that allows one to implement coordination primitives for cooperating management agents based on the Simple Network Management Protocol (SNMP). The multicast extensions presented in this paper allow one to maintain group information of cooperating SNMP agents. We also

  17. WIMAX Basics From PHY Layer to Scheduling And Multicasting Approaches

    Directory of Open Access Journals (Sweden)

    Khaled Elleithy

    2011-02-01

    Full Text Available WiMAX (Worldwide Interoperability for Microwave Access is an emerging broadband wirelesstechnology for providing Last mile solutions for supporting higher bandwidth and multiple serviceclasses with various quality of service requirement. The unique architecture of the WiMAX MAC andPHY layers that uses OFDMA to allocate multiple channels with different modulation schema andmultiple time slots for each channel allows better adaptation of heterogeneous user’s requirements. Themain architecture in WiMAX uses PMP (Point to Multipoint, Mesh mode or the new MMR (Mobile Multihop Mode deployments where scheduling and multicasting have different approaches. In PMP SS(Subscriber Station connects directly to BS (Base Station in a single hop route so channel conditionsadaptations and supporting QoS for classes of services is the key points in scheduling, admission controlor multicasting, while in Mesh networks SS connects to other SS Stations or to the BS in a multi hoproutes, the MMR mode extends the PMP mode in which the SS connects to either a relay station (RS orto Bs. Both MMR and Mesh uses centralized or distributed scheduling with multicasting schemas basedon scheduling trees for routing. In this paper a broad study is conducted About WiMAX technology PMPand Mesh deployments from main physical layers features with differentiation of MAC layer features toscheduling and multicasting approaches in both modes of operations.

  18. Polynomial Time Algorithms for Multicast Network Code Construction

    NARCIS (Netherlands)

    Jaggi, S.; Sanders, P.; Chou, P.A.; Effros, M.; Egner, S.; Jain, K.; Tolhuizen, L.M.G.

    2005-01-01

    The famous max-flow min-cut theorem states that a source node can send information through a network ( ) to a sink node at a rate determined by the min-cut separating and . Recently, it has been shown that this rate can also be achieved for multicasting to several sinks provided that the

  19. Algoritmo de balanceo de carga aplicado a enrutamiento multicast

    Directory of Open Access Journals (Sweden)

    Yezid Donoso Meisel

    2004-01-01

    Full Text Available En este artículo se proponen las bases para la creación del protocolo de enrutamiento multicast con características de ingeniería de tráfico: Pim-Dm/Sm-Te. Este protocolo consistiría en una serie de modificaciones realizadas al protocolo multicast Pim-Dm/ Sm, para permitir que este protocolo realice balanceo de carga y sirva como fuente de información a protocolos de reserva de recursos. Inicialmente se presentan definiciones y conceptos necesarios para la comprensión del funcionamiento del protocolo, tales como enrutamiento multicast en modo denso y enrutamiento multicast en modo esparcido. Se prosigue con la definición y explicación del funcionamiento de Pim-Dm/Sm, seguida de la propuesta y explicación de su funcionamiento. Por último, el lector tendrá acceso a resultados obtenidos a través de la herramienta de simulación, que confirman la utilidad del protocolo

  20. The optimal joint power and rate adaptation for mobile multicast

    DEFF Research Database (Denmark)

    Wang, Haibo; Schwefel, Hans-Peter; Toftegaard, Thomas S.

    2008-01-01

    In this paper we have investigated the joint power and rate adaptation strategies for multicast services for downlink communication. We have proposed a theoretical framework to find out the achievable spectrum efficiency upper boundary of such a scenario and the corresponding optimal solution for...

  1. QoS multicast routing algorithm based on GA

    Institute of Scientific and Technical Information of China (English)

    李腊元; 李春林

    2004-01-01

    The multicast routing problem with multiple QoS constraints in networks with uncertain parameters is discussed, and a network model that is suitable to research such QoS multicast routing problem is described. The QMRGA,a multicast routing policy for Internet, mobile network or other high-performance networks is mainly presented, which is based on the genetic algorithm(GA), and can provide QoS-sensitive paths in a scalable and flexible way in the network environment with uncertain parameters. The QMRGA can also optimize the network resources such as bandwidth and delay, and can converge to the optimal or near-optimal solution within few iterations, even for the network environment with uncertain parameters. The incremental rate of computational cost can be close to a polynomial and is less than exponential rate. The performance measures of the QMRGA are evaluated by using simulations. The results show that QMRGA provides an available approach to QoS multicast routing in network environment with uncertain parameters.

  2. Genetic based optimization for multicast routing algorithm for MANET

    Indian Academy of Sciences (India)

    C Rajan; N Shanthi

    2015-12-01

    Mobile Ad hoc Network (MANET) is established for a limited period, for special extemporaneous services related to mobile applications. This ad hoc network is set up for a limited period, in environments that change with the application. While in Internet the TCP/IP protocol suite supports a wide range of application, in MANETs protocols are tuned to specific customer/application. Multicasting is emerging as a popular communication format where the same packet is sent to multiple nodes in a network. Routing in multicasting involves maintaining routes and finding new node locations in a group and is NP-complete due to the dynamic nature of the network. In this paper, a Hybrid Genetic Based Optimization for Multicast Routing algorithm is proposed. The proposed algorithm uses the best features of Genetic Algorithm (GA) and particle swarm optimization (PSO) to improve the solution. Simulations were conducted by varying number of mobile nodes and results compared with Multicast AODV (MAODV) protocol, PSO based and GA based solution. The proposed optimization improves jitter, end to end delay and Packet Delivery Ratio (PDR) with faster convergence.

  3. Multicast Congestion Control Mechanism Based on QPID-AVQ%基于QPID-AVQ的组播拥塞控制机制

    Institute of Scientific and Technical Information of China (English)

    康巧燕; 王建峰; 王蓉; 黄红蓓

    2012-01-01

    针对现有多媒体组播拥塞控制协议的不足,提出基于QPID虚拟队列管理的组播拥塞控制机制QPID-MCC.QPID-MCC在瓶颈路由器中采用QPID-AVQ队列管理策略,结合显式拥塞指示(ECN),按照一定的概率标记新到分组.接收端依据标记概率计算期望的TCP友好速率.发送端依据接收端的反馈信息并结合多媒体的最小带宽需求调整发送速率.仿真结果表明,QPID-MCC具有平滑稳定的发送速率、较好的公平性和较快的拥塞响应速度,并能满足最小带宽要求,保证多媒体业务的服务质量.%To settle the problems existing in multimedia multicast congestion control protocols, a multicast congestion control mechanism based on QPID-AVQ is proposed, termed QPID-MCC. QPID-MCC introduces QPID-AVQ queue management strategy and Explicit Congestion Notification(ECN) technology in the bottleneck router, so that enables the router to mark the new arriving packets in accordance with a certain probability computed by QPID-AVQ algorithm. The receivers calculate the expected TCP-friendly rate based on marking probability, and the sender adjusts the sending rate according to the feedback information from the receiver and the minimum bandwidth requirements of multimedia services. Simulation results show that QPID-MCC has a smooth and stable sending rate, good fairness and fast response to congestion, and can ensure minimum bandwidth requirement of multimedia services.

  4. Studies on Routing Optimization of Fast and Hierarchical Mobile Multicast%快速分层移动组播的路径优化研究

    Institute of Scientific and Technical Information of China (English)

    李彬; 冯祖洪

    2015-01-01

    随着科学技术的飞速发展,多媒体通信的需求导致了组播技术的快速进步。如何节约网络资源,为移动设备提供更好的支持也引起了人们的普遍关注。由于组播具有可扩展性强、高效的特点,因此移动组播的应用已经得到了越来越多的关注。本文根据快速分层移动组播现有算法中的传输路径问题,介绍一种新的路由路径选择方法。该算法依据移动节点在新接入点停留的时间长短,选择不同的数据传输路径加入组播。可以优化组播分组的传输路径,有效减少网络资源的浪费。%With the rapid progress of science and technology, the requirement of multimedia communication let to the rapid advancement of the multicast technology. How to save network resources and determine the best way to provide services to mobile devices is the most important issue need to solve. As multicast naturally has the merit of high scalability and efficiency, more and more people pay attention to mobile multicast. Based on the transmission path problem of the fast and hierarchical mobile multicast, this paper introduces a new method. which is an improved algorithm based on the staying time of mobile devices under new access router, through prediction staying time mobile devices, it chooses a better path to join multicast. This new method can optimization routing path and save network resources.

  5. Quantum broadcast channels

    CERN Document Server

    Yard, J; Devetak, I; Yard, Jon; Hayden, Patrick; Devetak, Igor

    2006-01-01

    We analyze quantum broadcast channels, which are quantum channels with a single sender and many receivers. Focusing on channels with two receivers for simplicity, we generalize a number of results from the network Shannon theory literature which give the rates at which two senders can receive a common message, while a personalized one is sent to one of them. Our first collection of results applies to channels with a classical input and quantum outputs. The second class of theorems we prove concern sending a common classical message over a quantum broadcast channel, while sending quantum information to one of the receivers. The third group of results we obtain concern communication over an isometry, giving the rates at quantum information can be sent to one receiver, while common quantum information is sent to both, in the sense that tripartite GHZ entanglement is established. For each scenario, we provide an additivity proof for an appropriate class of channels, yielding single-letter characterizations of the...

  6. Satellites in Canadian broadcasting

    Science.gov (United States)

    Siocos, C. A.

    The involvement of Canadian broadcasting and related enterprises in satellite telecommunications is surveyed. This includes point-to-point transmissions and direct ones to the general public. The mode of such utilizations is indicated in both these cases. For the forthcoming DBS systems the many types of service offerings and utilization concepts under discussion elasewhere are presented as well as the business prospects and regulatory climate offering them.

  7. Broadcast sound technology

    CERN Document Server

    Talbot-Smith, Michael

    1990-01-01

    Broadcast Sound Technology provides an explanation of the underlying principles of modern audio technology. Organized into 21 chapters, the book first describes the basic sound; behavior of sound waves; aspects of hearing, harming, and charming the ear; room acoustics; reverberation; microphones; phantom power; loudspeakers; basic stereo; and monitoring of audio signal. Subsequent chapters explore the processing of audio signal, sockets, sound desks, and digital audio. Analogue and digital tape recording and reproduction, as well as noise reduction, are also explained.

  8. Reliable Multicasting for Device-to-Device Radio Underlaying Cellular Networks

    CERN Document Server

    Yang, Wei; Li, Lihua

    2010-01-01

    This paper proposes Leader in Charge (LiC), a reliable multicast architecture for device-to-device (D2D) radio underlaying cellular networks. The multicast-requesting user equipments (UEs) in close proximity form a D2D cluster to receive the multicast packets through cooperation. In addition to receiving the multicast packets from the eNB, UEs share what they received from the multicast on short-range links among UEs, namely the D2D links, to exploit the wireless resources a more efficient way. Consequently, we show that utilizing the D2D links in cellular networks increases the throughput of a multicast session by means of simulation. We also discuss some practical issues facing the integration of LiC into the current cellular networks. In particular, we propose efficient delay control mechanism to reduce the average and maximum delay experienced by LiC users, which is further confirmed by the simulation results.

  9. An Approach to Improve the State Scalability of Source Specific Multicast

    Directory of Open Access Journals (Sweden)

    S. A. Al-Talib

    2009-01-01

    Full Text Available Problem statement: Source Specific Multicast (SSM is an acceptable solution for current multicast applications; since the driving applications to date are one to many, including Internet TV, distance learning, file distribution and streaming media. Approach: It was useful for billing, address allocation and security. SSM still had serious state scalability problem when there were a large number of simultaneous on-going multicast groups in the network. Results: In this study, a scheme had been devised to improve the state scalability of source specific multicast. The scheme consisted of two stages: Conclusion/Recommendations: The first stage was to cluster the receivers based on their IP addresses and the second stage was to reduce the multicast state at routers. In order to prove the correctness of the proposed scheme, it had been applied to multicast trees built by other researchers. The results of the comparison approved our statement.

  10. Digital video and audio broadcasting technology a practical engineering guide

    CERN Document Server

    Fischer, Walter

    2010-01-01

    Digital Video and Audio Broadcasting Technology - A Practical Engineering Guide' deals with all the most important digital television, sound radio and multimedia standards such as MPEG, DVB, DVD, DAB, ATSC, T-DMB, DMB-T, DRM and ISDB-T. The book provides an in-depth look at these subjects in terms of practical experience. In addition it contains chapters on the basics of technologies such as analog television, digital modulation, COFDM or mathematical transformations between time and frequency domains. The attention in the respective field under discussion is focussed on aspects of measuring t

  11. Supporting IP dense mode multicast routing protocols in WDM all-optical networks

    Science.gov (United States)

    Salvador, Marcos R.; Heemstra de Groot, Sonia; Dey, Diptish

    2000-09-01

    Recent developments in all-optical networking and wavelength division multiplexing technologies allow for the support of optical multicasting, a missing feature towards the optical Internet. In this paper we propose a protocol to construct source-rooted WDM multicast trees. The protocol works under dense mode multicasting routing IP protocols and supports network nodes with different degrees of light splitting, wavelength conversion, and add/drop capabilities.

  12. Analysis and Optimization of Sparse Random Linear Network Coding for Reliable Multicast Services

    DEFF Research Database (Denmark)

    Tassi, Andrea; Chatzigeorgiou, Ioannis; Roetter, Daniel Enrique Lucani

    2016-01-01

    Point-to-multipoint communications are expected to play a pivotal role in next-generation networks. This paper refers to a cellular system transmitting layered multicast services to a multicast group of users. Reliability of communications is ensured via different random linear network coding (RL...... guarantees to predetermined fractions of users. The performance of the proposed optimization framework is then investigated in a LTE-A eMBMS network multicasting H.264/SVC video services....

  13. Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs

    Directory of Open Access Journals (Sweden)

    Woo-Yong Choi

    2009-01-01

    Full Text Available We propose the efficient reliable multicast MAC protocol based on the connectivity information among the recipients. Enhancing the BMMM (Batch Mode Multicast MAC protocol, the reliable multicast MAC protocol significantly reduces the RAK (Request for ACK frame transmissions in a reasonable computational time and enhances the MAC performance. By the analytical performance analysis, the throughputs of the BMMM protocol and our proposed MAC protocol are derived. Numerical examples show that our proposed MAC protocol increases the reliable multicast MAC performance for IEEE 802.11 wireless LANs.

  14. Multimedia Information Retrieval

    CERN Document Server

    Rueger, Stefan

    2009-01-01

    At its very core multimedia information retrieval means the process of searching for and finding multimedia documents; the corresponding research field is concerned with building the best possible multimedia search engines. The intriguing bit here is that the query itself can be a multimedia excerpt: For example, when you walk around in an unknown place and stumble across an interesting landmark, would it not be great if you could just take a picture with your mobile phone and send it to a service that finds a similar picture in a database and tells you more about the building -- and about its

  15. Effective I/O Scheme Based on RTP for Multimedia Communication Systems

    Institute of Scientific and Technical Information of China (English)

    Nam-Sup Park; Chong-Sun Hwang

    2006-01-01

    The prime standard for audio/video transport in IP networks is the Real-time Transport Protocol (RTP),and it is targeted at useful services for the transport of real-time multimedia data. RTP was originally designed for use in multicast conferences, using the lightweight sessions model. RTP (in particular, the data part) is so tightly coupled to the application that a number of people have developed libraries that implement RTP. However, little is known about the RTP overheads between user area and kernel area within operating system. Actually, unnecessary copying between user area and kernel area lowers the system efficiency. In this paper, we present the design and implementation of Enhanced Multimedia Input/Output Scheme based on LINUX. We brought focus to the crossover architecture supporting RTP. Our contributions are able to be summarized into two components: 1) Enhanced Input/Output (EIO) scheme based on LINUX improves the transmission speed by reducing the overheads generated from data copy and context switch between user area and kernel area. And this enables server-based system to transport multimedia data more efficiently. 2) Furthermore,Enhanced Input/Output scheme with RTP (EIORTP) scheme supports efficient multimedia data transmission architecture.The two schemes improve the performance of massive multimedia data transmission.

  16. New Generation of Broadcasting Satellite Systems: New Markets and Business Developments

    Science.gov (United States)

    Perrot, Bruno; Michel, Cyril; Villaret, Stéfanie

    2002-01-01

    Since the deployment of the first Digital Broadcasting Satellite Systems, European satellite operators and service providers have been faced with the continuously increasing demand for Digital Broadcasting Services. Their success is built on the availability of the MPEG and DVB standards. Undoubtedly, conventional digital television broadcasting is today the `Killer' application. Various service providers already offer multimedia applications through DVB-S systems based upon the `Push' technology. Although these services do not currently represent the core business for broadcasting satellite operators, their percentage is increasing. `Push' technology services include Data Carousel, Webcasting, Turbo Internet, File casting and so on. Such technology can support the implementation of different emerging multimedia services scenarios from Newsgroups, Network collaborative learning, and tele-medicine, to others that may be invented in the near future. The penetration rate of multi-channel television reception is still increasing. Broadcasting satellites benefit both from the development of new, more segmented and sophisticated offers and from the development of Internet services. Satellite is likely to enter these new markets at different levels of the value chain: Even if the satellite has demonstrated its capacity to fully serve the television, combinations with other networks may be necessary to address the new markets: at the consumer premises, Internet-related services will require a return path; at the backbone level, satellite becomes a component of a full telecommunications solution. This article focuses on the European market and proposes:

  17. Using multicast in the global communications infrastructure for group communication

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    1999-07-30

    International Monitoring System (IMS) stations and the International Data Centre (IDC) of the Preparatory Commission for the Comprehensive Nuclear-Test-Ban Treaty Organization generate data and products that must be transmitted to one or more receivers. The application protocols used to transmit the IMS data and IDC products will be CD-x and IMS-x and the World Wide Web (WWW). These protocols use existing Internet applications and Internet protocols to send their data. The primary Internet applications in use are electronic mail (e-mail) and the file transfer protocol (ftp). The primary Internet communication protocol in use is the Transmission Control Protocol (TCP), which provides reliable delivery to the receiver. These Internet applications and protocol provide unicast (point-to-point) communication. A message sent using unicast has a single recipient; any message intended for more than one recipient must be sent to each recipient individually. In the current design, the IDC and the National Data Centres (NDC's) provide data forwarding to the appropriate receivers. The overhead associated with using unicast to transmit messages to multiple receivers either directly or through a forwarder increases linearly with the number of receivers. In addition, using a forwarding site introduces possible delays and possible points of failure in the path to the receivers. Reliable multicast provides communication services similar to TCP but for a group of receivers. The reliable multicast protocol provides group membership services and message delivery ordering. If an IMS station were to send its data using reliable multicast instead of unicast, only sites that are members of the multicast group would receive the data at approximately the same time. This might provide an efficient means of disseminating station data or IDC data products to all receivers and eliminate or greatly reduce the need for data forwarding. Several commercial and research reliable multicast

  18. A Dynamic Adaptive Layered Multicast Congestion Control Mechanism

    Institute of Scientific and Technical Information of China (English)

    REN Liyong; LU Xianliang; WEI Qingsong; ZHOU Xu

    2003-01-01

    To solve the problem that most of existing layered multicast protocols cannot adapt to dynamic network conditions because their layers are coarsely granulated and static, a new congestion control mechanism for dynamic adaptive layered multicast(DALM) is presented. In this mechanism, a novel feedback aggregating algorithm is put forward, which can dynamically determine the number of layers and the rate of each layer, and can efficiently improve network bandwidth utilization ratio.Additionally, because all layers is transmitted in only one group, the intricate and time-consuming internet group management protocol(IGMP) operations, caused by receiver joining a new layer or leaving the topmost subscribed layer, are thoroughly eliminated. And this mechanism also avoids other problems resulted from multiple groups. Simulation results show that DALM is adaptive and TCP friendly.

  19. Effective multicasting algorithm for dynamic membership with delay constraint

    Institute of Scientific and Technical Information of China (English)

    CHEN Lin; XU Zheng-quan

    2006-01-01

    This paper proposes an effective heuristic algorithm for dynamic multicast routing with delay-constrained DDMR.The tree constructed by DDMR has the following characteristics: (1) multicast tree changes with the dynamic memberships; (2)the cost of the tree is as small as possible at each node addition/removal event; (3) all of the path delay meet a fixed delay constraint;(4) minimal perturbation to an existing tree. The proposed algorithm is based on "damage" and "usefulness" concepts proposed in previous work, and has a new parameter bf(Balancing Factor) for judging whether or not to rearrange a tree region when membership changes. Mutation operation in Genetic Algorithm (GA) is also employed to find an attached node for a new adding node.Simulation showed that our algorithm performs well and is better than static heuristic algorithms, in term of cost especially.

  20. Fault-Tolerant Tree-Based Multicasting in Mesh Multicomputers

    Institute of Scientific and Technical Information of China (English)

    WU Jie; CHEN Xiao

    2001-01-01

    We propose a fault-tolerant tree-based multicast algorithm for 2-dimensional (2-D) meshes based on the concept of the extended safety level which is a vector associated with each node to capture fault information in the neighborhood. In this approach each destination is reached through a minimum number of hops. In order to minimize the total number of traffic steps, three heuristic strategies are proposed. This approach can be easily implemented by pipelined circuit switching (PCS). A simulation study is conducted to measure the total number of traffic steps under different strategies. Our approach is the first attempt to address the faulttolerant tree-based multicast problem in 2-D meshes based on limited global information with a simple model and succinct information.

  1. A Bypass-Ring Scheme for a Fault Tolerant Multicast

    Directory of Open Access Journals (Sweden)

    V. Dynda

    2003-01-01

    Full Text Available We present a fault tolerant scheme for recovery from single or multiple node failures in multi-directional multicast trees. The scheme is based on cyclic structures providing alternative paths to eliminate faulty nodes and reroute the traffic. Our scheme is independent of message source and direction in the tree, provides a basis for on-the-fly repair and can be used as a platform for various strategies for reconnecting tree partitions. It only requires an underlying infrastructure to provide a reliable routing service. Although it is described in the context of a message multicast, the scheme can be used universally in all systems using tree-based overlay networks for communication among components.

  2. Design of an IPTV Multicast System for Internet Backbone Networks

    Directory of Open Access Journals (Sweden)

    T. H. Szymanski

    2010-01-01

    Full Text Available The design of an IPTV multicast system for the Internet backbone network is presented and explored through extensive simulations. In the proposed system, a resource reservation algorithm such as RSVP, IntServ, or DiffServ is used to reserve resources (i.e., bandwidth and buffer space in each router in an IP multicast tree. Each router uses an Input-Queued, Output-Queued, or Crosspoint-Queued switch architecture with unity speedup. A recently proposed Recursive Fair Stochastic Matrix Decomposition algorithm used to compute near-perfect transmission schedules for each IP router. The IPTV traffic is shaped at the sources using Application-Specific Token Bucker Traffic Shapers, to limit the burstiness of incoming network traffic. The IPTV traffic is shaped at the destinations using Application-Specific Playback Queues, to remove residual network jitter and reconstruct the original bursty IPTV video streams at each destination. All IPTV traffic flows are regenerated at the destinations with essentially zero delay jitter and essentially-perfect QoS. The destination nodes deliver the IPTV streams to the ultimate end users using the same IPTV multicast system over a regional Metropolitan Area Network. It is shown that all IPTV traffic is delivered with essentially-perfect end-to-end QoS, with deterministic bounds on the maximum delay and jitter on each video frame. Detailed simulations of an IPTV distribution system, multicasting several hundred high-definition IPTV video streams over several essentially saturated IP backbone networks are presented.

  3. VETERAN BROADCASTER LEADS OLYMPIC CHARGE

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    With its leadership team and technological know-how, the Beijing Olympic Broadcasting Co. Ltd. endeavors to bring the Olympics live to people around the globe The first thing that Ma Guoli, Chief Operating Officer of the Beijing Olympic Broadcasting Co.

  4. Efficient and secure source authentication scheme for multicast user authentication

    Institute of Scientific and Technical Information of China (English)

    JEONG; Yoon-su; LEE; Sang-hyuk; SHIN; Seung-soo

    2013-01-01

    Multicast technology application has been widely utilized in broadband internet. Source authentication is one of the most needs for many multicast applications transferring real-time information such as stream video and online news. Because multicast current services provided to the group members are changed dynamically, data transferring by a group member is not used by the recipient. In order to verify the identity of the sender who sent the packet and to make sure that the data have not been tampered, an optimized source authentication scheme has been proposed to transfer the authentication information not to the next-door packet. The proposed method for multiple packets authenticates the source with a limited number of electronic signatures. The proposed method can reduce overhead compared to the method by adding a digital signature for every packet. In addition, by sending the generated electronic signature to the first packet and the last packet, it prevents the loss of consecutive packets, as well as a source authentication can be provided in real-time services.

  5. Joint Network Coding for Interfering Wireless Multicast Networks

    CERN Document Server

    Qureshi, Jalaluddin; Cai, Jianfei

    2011-01-01

    Interference in wireless networks is one of the key-capacity limiting factor. The multicast capacity of an ad- hoc wireless network decreases with an increasing number of transmitting and/or receiving nodes within a fixed area. Digital Network Coding (DNC) has been shown to improve the multicast capacity of non-interfering wireless network. However recently proposed Physical-layer Network Coding (PNC) and Analog Network Coding (ANC) has shown that it is possible to decode an unknown packet from the collision of two packet, when one of the colliding packet is known a priori. Taking advantage of such collision decoding scheme, in this paper we propose a Joint Network Coding based Cooperative Retransmission (JNC- CR) scheme, where we show that ANC along with DNC can offer a much higher retransmission gain than that attainable through either ANC, DNC or Automatic Repeat reQuest (ARQ) based retransmission. This scheme can be applied for two wireless multicast groups interfering with each other. Because of the broa...

  6. A Genetic Algorithms Based Approach for Group Multicast Routing

    Directory of Open Access Journals (Sweden)

    Luca Sanna Randaccio

    2006-08-01

    Full Text Available Whereas multicast transmission in one-to-many communications allows the operator to drastically save network resources, it also makes the routing of the traffic flows more complex then in unicast transmissions. A huge amount of possible trees have to be considered and analyzed to find the appropriate routing paths. To address this problem, we propose the use of the genetic algorithms (GA, which considerably reduce the number of solutions to be evaluated. A heuristic procedure is first used to discern a set of possible trees for each multicast session in isolation. Then, the GA are applied to find the appropriate combination of the trees to comply with the bandwidth needs of the group of multicast sessions simultaneously. The goodness of each solution is assessed by means of an expression that weights both network bandwidth allocation and one-way delay. The resulting cost function is guided by few parameters that can be easily tuned during traffic engineering operations; an appropriate setting of these parameters allows the operator to configure the desired balance between network resource utilization and provided quality of service. Simulations have been performed to compare the proposed algorithm with alternative solutions in terms of bandwidth utilization and transmission delay.

  7. Adaptive live multicast video streaming of SVC with UEP FEC

    Science.gov (United States)

    Lev, Avram; Lasry, Amir; Loants, Maoz; Hadar, Ofer

    2014-09-01

    Ideally, video streaming systems should provide the best quality video a user's device can handle without compromising on downloading speed. In this article, an improved video transmission system is presented which dynamically enhances the video quality based on a user's current network state and repairs errors from data lost in the video transmission. The system incorporates three main components: Scalable Video Coding (SVC) with three layers, multicast based on Receiver Layered Multicast (RLM) and an UnEqual Forward Error Correction (FEC) algorithm. The SVC provides an efficient method for providing different levels of video quality, stored as enhancement layers. In the presented system, a proportional-integral-derivative (PID) controller was implemented to dynamically adjust the video quality, adding or subtracting quality layers as appropriate. In addition, an FEC algorithm was added to compensate for data lost in transmission. A two dimensional FEC was used. The FEC algorithm came from the Pro MPEG code of practice #3 release 2. Several bit errors scenarios were tested (step function, cosine wave) with different bandwidth size and error values were simulated. The suggested scheme which includes SVC video encoding with 3 layers over IP Multicast with Unequal FEC algorithm was investigated under different channel conditions, variable bandwidths and different bit error rates. The results indicate improvement of the video quality in terms of PSNR over previous transmission schemes.

  8. Commercial satellite broadcasting for Europe

    Science.gov (United States)

    Forrest, J. R.

    1988-12-01

    A review is presented of the current television broadcasting situation in European countries, which involves a varied mix of terrestrial VHF or UHF systems and cable networks. A small market has emerged in Europe for receivers using the low-power telecommunications satellite transmission between the program providers and cable network companies. This is expected to change with the launch of medium-power pan-European telecommunication satellites (e.g. ASTRA, EUTELSAT II), which are now directly addressing the market of home reception. DBS (direct broadcast satellite) in the UK, using the D-MAC transmission standard, will offer three additional television channels, data broadcasting services, and a planned evolution to compatible forms of wide-screen, high-definition television. Comments are given on receiver and conditional access system standardization. Some views are expressed on satellite broadcasting as part of an overall broadcasting framework for the future.

  9. Broadcast-Based Spatial Queries

    Institute of Scientific and Technical Information of China (English)

    Kwang-Jin Park; Moon-Bae Song; Chong-Sun Hwang

    2005-01-01

    Indexing techniques have been developed for wireless data broadcast environments, in order to conserve the scarce power resources of the mobile clients. However, the use of interleaved index segments in a broadcast cycle increases the average access latency for the clients. In this paper, the broadcast-based spatial query processing methods (BBS)are presented for the location-based services. In the BBS, broadcasted data objects are sorted sequentially based on their locations, and the server broadcasts the location dependent data along with an index segment. Then, a sequential prefetching and caching scheme is designed to reduce the query response time. The performance of this scheme is investigated in relation to various environmental variables, such as the distributions of the data objects, the average speed of the clients and the size of the service area.

  10. Evolution of broadcast content distribution

    CERN Document Server

    Beutler, Roland

    2017-01-01

    This book discusses opportunities for broadcasters that arise with the advent of broadband networks, both fixed and mobile. It discusses how the traditional way of distributing audio-visual content over broadcasting networks has been complemented by the usage of broadband networks. The author shows how this also gives the possibility to offer new types of interactive or so-called nonlinear services. The book illustrates how change in distribution technology is accelerating the need for broadcasters around the world to adapt their content distribution strategy and how it will impact the portfolios of content they offer. Outlines the shift in broadcast content distribution paradigms and related strategic issues Provides an overview of the new broadcasting ecosystem encompassing new types of content, user habits, expectations, and devices Discusses complementary usage of different distribution technologies and platforms.

  11. Design, Implementation, and Performance Evaluation of Efficient PMIPv6 Based Mobile Multicast Sender Support Schemes

    Directory of Open Access Journals (Sweden)

    Lili Wang

    2015-01-01

    Full Text Available Proxy Mobile IPv6 (PMIPv6 is proposed as a promising network-based mobility management protocol, which does not need any participation of mobile nodes. PMIPv6 does not support the multicast well and most of the current research concentrates on the mobile multicast receiver. However, the mobile multicast sender is also very important and challenging, which has not been addressed well. Therefore, in this paper we propose two efficient PMIPv6 based mobile multicast sender support schemes which are PMIP bidirectional tunneling (PMIP-BT and PMIP direct routing (PMIP-DR. In the PMIP-BT, the multicast traffic can be delivered through the PMIPv6 bidirectional tunnel, while, in the PMIP-DR, the multicast data can be transmitted via an optimized direct multicast routing. Both of them can support the multicast sender mobility transparently enabled in the PMIPv6 networks. We evaluate the performance of the proposed schemes by theoretical analysis, and the numerical results show that the proposed schemes have a better performance in terms of the signaling cost than the current schemes. Meanwhile, the proposed schemes are also implemented on the test bed, and the experimental results not only verify the validity and feasibility of our proposed schemes, but also conclude the different scenarios to which they are applicable.

  12. Almost optimal distributed M2M multicasting in wireless mesh networks

    DEFF Research Database (Denmark)

    Xin, Qin; Manne, Fredrik; Zhang, Yan

    2012-01-01

    nodes. It is known that the computation of an optimal M2M multicasting schedule isNP-hard. We present a fully distributed deterministic algorithm for such an M2M multicasting problem and analyze its time complexity. We show that if the maximum hop distance between any two out of the k participants is d...

  13. Fair Resource Allocation in Networks with Coexisting Unicast and Multirate Multicast Flows

    Institute of Scientific and Technical Information of China (English)

    Dong Qian(董谦); Xie Jianying; Liu Fengqing; Zhu Xu

    2004-01-01

    To maximize the aggregate user utility in networks with both multirate multicast and unicast traffic, a unified convex program formulation of the problem is used to integrate multicast and unicast sessions into a common framework, which also takes into account the heterogeneity of multicast receivers. By applying a penalty function approach, a heuristic rate control algorithm is derived. In the distributed implementation of the algorithm in IP networks, core routers employ Random Early Detection (RED) to mark packets in the case of congestion; end-users analyze congestion feedback information and update their rates to calculated optimal values. With an appropriate choice of utility functions and parameters, multicast and unicast sessions can share network resources in the proportional fair manner. Simulation results prove the algorithm's effectiveness. Study is also done on the effect of bandwidth discretization density upon resource allocation fairness in a layered multicast scenario.

  14. Scalable Base-Station Model-Based Multicast in Wireless Sensor Networks

    Institute of Scientific and Technical Information of China (English)

    Shao-Liang Peng; Shan-Shan Li; Lei Chen; Yu-Xing Peng; Nong Xiao

    2008-01-01

    Multicast is essential for wireless sensor network (WSN) applications. Existing multicast protocols in WSNs are often designed in a P2P pattern, assuming small number of destination nodes and frequent changes in network topologies.In order to truly adopt multicast in WSNs, we propose a base-station model-based multicast, SenCast, to meet the general requirements of applications. SenCast is scalable and energy-efficient for large group communications in WSNs. Theoretical analysis shows that SenCast is able to approximate the Minimum Nonleaf Nodes (MNN) problem to a ratio of In |R| (R is the set of all destinations), the best known lowest bound. We evaluate our design through comprehensive simulations and prototype implementations on Mica2 motes. Experimental results demonstrate that SenCast outperforms previous multicast protocols including the most recent work uCast.

  15. Multiple constraints QoS multicast routing optimization algorithm in MANET based on GA

    Institute of Scientific and Technical Information of China (English)

    Baolin Sun; Shangchao Pi; Chao Gui; Yue Zeng; Bing Yan; Wenxiang Wang; Qianqing Qin

    2008-01-01

    Usually multiple quality of service (QoS) guarantees are required in most multicast applications. This paper presents a multiple constraints algorithm for multicast traffic engineering in mobile ad hoc networks (MANET). The proposed algorithm is a new version of multiple constraints QoS multicast routing optimization algorithm in MANET based on genetic algorithm (MQMGA). The proposed MQMGA can optimize the maximum link utilization, the cost of the multicast tree, the selection of the long-life path, the average delay and the maximum end-to-end delay. Experimental result shows that the approach is efficient, has promising performance in multicast traffic engineering and for evaluating the route stability in dynamic mobile networks.

  16. Multimedia image and video processing

    CERN Document Server

    Guan, Ling

    2012-01-01

    As multimedia applications have become part of contemporary daily life, numerous paradigm-shifting technologies in multimedia processing have emerged over the last decade. Substantially updated with 21 new chapters, Multimedia Image and Video Processing, Second Edition explores the most recent advances in multimedia research and applications. This edition presents a comprehensive treatment of multimedia information mining, security, systems, coding, search, hardware, and communications as well as multimodal information fusion and interaction. Clearly divided into seven parts, the book begins w

  17. Broadcasting Correlated Gaussians

    CERN Document Server

    Bross, Shraga; Tinguely, Stephan

    2007-01-01

    We consider the transmission of a bi-variate Gaussian source over a one-to-two power-limited Gaussian broadcast channel. Receiver 1 observes the transmitted signal corrupted by Gaussian noise and wishes to estimate the first component of the source. Receiver 2 observes the transmitted signal in larger Gaussian noise and wishes to estimate the second component. We seek to characterize the pairs of mean squared-error distortions that are simultaneously achievable at the two receivers. Our result is that below a certain SNR-threshold an "uncoded scheme" that sends a linear combination of the source components is optimal. The SNR-theshold can be expressed as a function of the source correlation and the distortion at Receiver 1.

  18. Simultaneous multichannel wavelength multicasting and XOR logic gate multicasting for three DPSK signals based on four-wave mixing in quantum-dot semiconductor optical amplifier.

    Science.gov (United States)

    Qin, Jun; Lu, Guo-Wei; Sakamoto, Takahide; Akahane, Kouichi; Yamamoto, Naokatsu; Wang, Danshi; Wang, Cheng; Wang, Hongxiang; Zhang, Min; Kawanishi, Tetsuya; Ji, Yuefeng

    2014-12-01

    In this paper, we experimentally demonstrate simultaneous multichannel wavelength multicasting (MWM) and exclusive-OR logic gate multicasting (XOR-LGM) for three 10Gbps non-return-to-zero differential phase-shift-keying (NRZ-DPSK) signals in quantum-dot semiconductor optical amplifier (QD-SOA) by exploiting the four-wave mixing (FWM) process. No additional pump is needed in the scheme. Through the interaction of the input three 10Gbps DPSK signal lights in QD-SOA, each channel is successfully multicasted to three wavelengths (1-to-3 for each), totally 3-to-9 MWM, and at the same time, three-output XOR-LGM is obtained at three different wavelengths. All the new generated channels are with a power penalty less than 1.2dB at a BER of 10(-9). Degenerate and non-degenerate FWM components are fully used in the experiment for data and logic multicasting.

  19. Duty-Cycle-Aware Minimum Energy Multicasting of Passive RFID Wake-up Radios for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    M. Pavan Kumar Reddy

    2014-04-01

    Full Text Available In duty-cycled wireless sensor networks, the nodes switch between active and dormant states, and each node determine its active/dormant schedule independently. This complicates the Minimum Energy Multicasting (MEM problem in wireless sensor networks both for one-to-many multicasting and for all-to-all multicasting. In the case of one-to-many multicasting, we present a formalization of the Minimum-Energy Multicasting Tree Construction and Scheduling (MEMTCS problem. We prove that MEMTCS problem is NP-hard and propose a polynomial-time approximation algorithm for the MEMTCS problem. In the case of all-to-all multicasting, we prove that the Minimum-Energy Multicast Backbone Construction and Scheduling (MEMBCS problem is also NP-hard and present an approximation algorithm for it. Compared to duty cycling, wake-up radios save more energy by reducing unnecessary wake-ups and collisions.

  20. MULTIMEDIA ON GEOGRAPHIC NETWORK

    OpenAIRE

    Merlanti, Danilo

    2012-01-01

    In this thesis we investigate the topic of the multimedia contents distribution on a geo- graphic network which is a rarefied and huge field. First of all we have to classify the main parts necessary in the multimedia distribution on a geographic network. The main aspects of a geographic network that will be highlighted in this thesis are: the mechanism used to retrieve the sources of the multimedia content; in the case of the peer-to-peer network on geographic network one of t...

  1. El cuento multimedia interactivo

    OpenAIRE

    Perceval Verde, José María; Tejedor, Santiago

    2006-01-01

    En el marco del presente artículo se reflexiona sobre las posibilidades educativas del cuento multimedia interactivo. En este sentido y tras analizar los orígenes y evolución del cuento, se estudian las novedades que la hipertextualidad, interactividad y convergencia multimedia introducen en la creación de historias ideadas con una finalidad educativa en el marco de la Sociedad de la Información. Del mismo modo, se presenta un proyecto de cuento multimedia interactivo desarrollado en el Máste...

  2. Climate Matters: Increasing Climate Literacy Through Broadcast Meteorologists

    Science.gov (United States)

    Sanford, T. J.; Placky, B. W.

    2015-12-01

    Broadcast meteorologists are among the most trusted members of the media landscape and they have a unique opportunity to reach the broad public with information about climate change. A recent survey by Maibach, et al. (2015) has shown that more than 90% of TV weathercasters think that their audience is at least somewhat interested in learning about the local impacts of climate change and 7 in 10 think that it is appropriate for them to report the science of climate change to their audience. But about half of these TV weathercasters have experienced obstacles to reporting climate change - citing lack of time to research and produce material, in addition to lack of access to appropriate visuals/graphics and access to trusted scientific information. Climate Matters is an NSF funded program that partners with broadcast meteorologists to deliver scientifically sound climate change information to the public that is local and relevant. A team of climate scientists, meteorologists, data analysts, journalists, and multimedia artists analyze and prepare content on a weekly basis so that it may be readily included in a broadcast weather segment, online or during community outreach. The program started as a pilot project with just one meteorologist in 2010 before Climate Central launched a full-time, nationwide program in 2012. Since then, Climate Matters has grown to include over 250 meteorologists strong and in more than 100 markets across the country, including Spanish language TV stations.

  3. Mathematics for multimedia

    CERN Document Server

    Wickerhauser, Mladen Victor

    2003-01-01

    Mathematics and Multimedia focuses on the mathematics behind multimedia applications. This timely and thoroughly modern text is a rigorous survey of selected results from algebra and analysis, requiring only undergraduate math skills.The topics are `gems'' chosen for their usefulness in understanding and creating application software for multimedia signal processing and communication.The book is aimed at a wide audience, including computer science and mathematics majors and those interested in employing mathematics in multimedia design and implementation. For the instructor, the material is divided into six chapters that may be presented in six lecture hours each. Thus, the entire text may be covered in one semester, with time left for examinations and student projects. For the student,there are more than 100 exercises with complete solutions, and numerous example programs in Standard C. Each chapter ends with suggestions for further reading. A companion website provides more insight for both instructors an...

  4. Multimedia communications and networking

    CERN Document Server

    da Silva, Mario Marques

    2012-01-01

    The result of decades of research and international project experience, Multimedia Communications and Networking provides authoritative insight into recent developments in multimedia, digital communications, and networking services and technologies. Supplying you with the required foundation in these areas, it illustrates the means that will allow for improved digital communications and networks. The book starts with a review of the fundamental concepts, requirements, and constraints in networks and telecommunications. It describes channel disturbances that can hinder system performance--inclu

  5. Unified broadcast in sensor networks

    DEFF Research Database (Denmark)

    Hansen, Morten Tranberg; Jurdak, Raja; Kusy, Branislav

    2011-01-01

    Complex sensor network applications include multiple services such as collection, dissemination, time synchronization, and failure detection protocols. Many of these protocols require local state maintenance through periodic broadcasts which leads to high control overhead. Recent attempts...

  6. Design of mine-used digital broadcasting system%矿用数字广播系统设计

    Institute of Scientific and Technical Information of China (English)

    钱建生; 李双双; 左慢慢; 赵骏逸; 李军鸿

    2013-01-01

    针对煤矿井下广播系统模拟音频广播方式存在灵活性差、语音通信范围小等问题,提出了一种新型的矿用数字广播系统设计方案,介绍了系统的总体结构、音频终端及网关程序的设计.该系统将音频终端接入工业以太网,实现了分组和定点广播,解决了井下的单播、组播问题.%For problems that underground broadcasting system with analog audio broadcasting mode has poor flexibility and small voice communication range, the paper proposed design scheme of a new kind of mine-used digital broadcasting system, introduced designs of overall structure of the system, audio terminal and gateway program. The system accesses the audio terminal in industrial Ethernet, realizes packet and designated broadcasting, which solves problems of underground unicast and multicast.

  7. Minimum Interference Channel Assignment Algorithm for Multicast in a Wireless Mesh Network.

    Science.gov (United States)

    Choi, Sangil; Park, Jong Hyuk

    2016-12-02

    Wireless mesh networks (WMNs) have been considered as one of the key technologies for the configuration of wireless machines since they emerged. In a WMN, wireless routers provide multi-hop wireless connectivity between hosts in the network and also allow them to access the Internet via gateway devices. Wireless routers are typically equipped with multiple radios operating on different channels to increase network throughput. Multicast is a form of communication that delivers data from a source to a set of destinations simultaneously. It is used in a number of applications, such as distributed games, distance education, and video conferencing. In this study, we address a channel assignment problem for multicast in multi-radio multi-channel WMNs. In a multi-radio multi-channel WMN, two nearby nodes will interfere with each other and cause a throughput decrease when they transmit on the same channel. Thus, an important goal for multicast channel assignment is to reduce the interference among networked devices. We have developed a minimum interference channel assignment (MICA) algorithm for multicast that accurately models the interference relationship between pairs of multicast tree nodes using the concept of the interference factor and assigns channels to tree nodes to minimize interference within the multicast tree. Simulation results show that MICA achieves higher throughput and lower end-to-end packet delay compared with an existing channel assignment algorithm named multi-channel multicast (MCM). In addition, MICA achieves much lower throughput variation among the destination nodes than MCM.

  8. A Novel Approach to Overlay Multicasting Schemes for Multi-Hop Ad-Hoc Networks

    Science.gov (United States)

    Kang, Namhi; Oh, Jejun; Kim, Younghan

    Multicast is an efficient transport mechanism for group-based community communications and mobile ad-hoc networks (MANET) is recently regarded as a promising solution for supporting ubiquitous computing as an underlying network technology. However, it is challenging to deploy the multicast mechanism used in a wired network directly into MANET owing to scarce resources in wireless networks and unpredictable changes in network topology. Several multicast mechanisms have been proposed in the literature to overcome these limitations. In MANET, especially, overlay multicasting schemes present several advantages over network-based multicasting schemes. However we have observed a common limitation of previously proposed overlay multicasting schemes. They introduce redundant data transmissions that waste network bandwidth and the battery of relay nodes. The observation motivated us to propose an efficient way to create and maintain a “semi-overlay structure” that utilizes a few nonmember nodes selected as branch nodes. The proposed scheme, called “SOMRP (Semi-overlay multicast routing protocol),” has been evaluated by using extensive network simulation in two different scenarios, comparing the performance of SOMRP with two previously proposed schemes. Simulation results show that SOMRP outperforms the two schemes in terms of the packet delivery ratio, transmission cost and end-to-end delay.

  9. A Supporting Efficient and Dynamic Multicasting Over Multiple Regions in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    S.Firthouse

    2012-02-01

    Full Text Available Designing multicast routing protocol is a big challenge due to difficulty in achieving group membership management, packet forwarding and maintenance of multicast structure over the dynamic network topology. In this paper, we proposed a novel Efficient Geographic Multicast Protocol (EGMP. A network wide zone-based bi-directional tree is used to achieve efficient membership management and multicast delivery. In Efficient EGMP an efficient distributed algorithm is used, that support dynamic changes to the multicast group during tree building and allows overlapping join/leave operations. The multicast tree is constructed based on zone depth, which is efficient in guiding tree branch building and tree structure maintenance. Nodes in the network self-organized into zones and zone-based bidirectional-tree-based distribution paths are built. Our simulation results demonstrate that EGMP has high packet delivery ratio, low control overhead and multicast group joining delay under all test scenarios, and is scalable to both group size and network size.

  10. A Study of Broadband Intelligent Network Implementing Video Conference and Multicast Routing Algorithm

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The dissertation studies the architecture of broadbandintelligent network (BIN) and implementation of video conference based on ATM network and of multicast routing problem on video conference using BIN under the aid of the important task-Study of IN and B-ISDN Integration (69896244)-sponsored by National Natural Science Fund. A lot of points of view and solutions are present. The main contributions in the dissertation are as follows: (1) Design the new architecture of BIN and improve the architecture of BIN proposed by ITU-T. It is easy to set up the connections of video conference using the new architecture of BIN.(2) Present the detailed scheme that BIN controls and implements video conference without specialized resource function, study the scheme of all the media on video conference transmitted and switched under the control of BIN, and discuss how to implement point-to-multipoint communications using BIN. (3) First present the scheme of implementing multicast routing algorithms on video conference using BIN.(4) Explicitly introduce a series of concepts including neighboring node, neighboring node set, neighboring edge, then propose an Adjustable Dynamic Multicast (ADM) routing algorithm which is suitable for video conference, analyze its performances, and prove the algorithm is appropriate and feasible. (5) Develop a degree-constrained dynamic multicast (DADM) routing algorithm which can find less cost multicast routing tree. The results of simulation and experiments confirm that DADM algorithm can find the less cost multicast tree. Finally, analyze the relation between the size of degree-constrained and value of multicast tree cost. (6) Present a delay-constrained dynamic multicast routing algorithm suitable for video conference characteristic, and advise a series of schemes reducing the delay of transmitting all the media on videoconference.(7) First propose implementing the reliable multicast routing transport protocol using BIN, thereby ACK implosion

  11. Ruteo multicast mediante algoritmos genéticos

    OpenAIRE

    Klenzi, Raúl O.; Sánchez Tores, Héctor A.; Ortega, Manuel Oscar; Naranjo, Viviana; Espósito, Gabriela

    2000-01-01

    Los sistemas o redes de comunicación construidos teniendo en cuenta el modelo de referencia OSI (Open Systems lnterconection) o la arquitectura de Internet, fueron diseñados para soportar servicios o comunicaciones punto a punto, donde la información fluye entre dos usuarios únicamente. Uno de los tópicos en el cual las redes de computadoras actuales están poniendo mucho énfasis, proviene de las aplicaciones multicast o de grupo. Estas involucran más de dos usuarios (estos usuarios definen...

  12. Blocking Analysis of Time-Division Multiplexed Multicast Switch

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The particular switch concerned here is a Three-Stage Time-space-time (TST) interconnection network and performs the time-division circuit switching. The input and output stages are Time Slot Interchangers (TSI). The central stage is a time-multiplexed switch with two ports per address. By exploiting the channel grouping at the central stage as well as reducing the average loading at each internal frame,the three-stage multicast switch has potential to remove almost all slot contention blockings.

  13. Distributed QoS-aware source-specific multicast routing protocol

    Institute of Scientific and Technical Information of China (English)

    WANG Jing; LIU Wei-ning; SONG Wei

    2005-01-01

    A distributed QoS (quality of service) -aware source-specific multicast routing protocol--DQSSMR is proposed to increase the successful join ratio and lower the overhead of the control message in QoS required multicast routing. By an improved searching strategy, the cost of message control is reduced and the successful join ratio is increased. The network load is balanced due to the distributed routing operation and the scalability is enhanced further because of the usage of SSM (source-specific multicast) service model in DQSSMR. The analysis results indicate that DQSSMR performs as expected.

  14. Dynamic Load Balancing Based on Restricted Multicast Tree in Homogeneous Multiprocessor Systems

    Institute of Scientific and Technical Information of China (English)

    LIU Bin; SHI Feng; GAO Yu-jin

    2008-01-01

    To decrease the cost of exchanging load information among processors, a dynamic load-balancing (DLB) algorithm which adopts multicast tree technology is proposed. The multicast tree construction rules are also proposed to avoid wrongly transferred or redundant DLB messages due to the overlapping of multicast trees. The proposed DLB algorithm is distributed controlled, sender initiated and can help heavily loaded processors with complete distribution of redundant loads with minimum number of executions. Experiments were executed to compare the effects of the proposed DLB algorithm and other three ones, the results prove the effectivity and practicability of the proposed algorithm in dealing with great scale compute-intensive tasks.

  15. Integration of look-ahead multicast and unicast scheduling for input-queued cell switches

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert

    2012-01-01

    -ofline (HOL) blocking problem that the weight-based algorithm (WBA) suffers from. Leveraging the FILter & Merge (FILM) scheme, multicast and unicast traffic are independently scheduled based on their requests. Decisions are integrated following a specific policy. Remainder is looped back to the filtering...... module that filters out the conflicting requests to ensure fairness. Simulation results show that comparing with the scheme using WBA for the multicast scheduling, the scheme proposed in this paper reduces the HOL blocking problem for multicast traffic and provides a significant improvement in terms...

  16. Uso extendido de árboles de distribución multicast por emisor

    OpenAIRE

    Rigotti, Guillermo

    2001-01-01

    Algunas clases de aplicaciones multicast, como RTP y multicast confiable consisten de un emisor y un conjunto de receptores que envían información de feedback a dicho emisor y al conjunto de receptores. Si el soporte multicast provisto está basado en árboles de distribución por emisor, dicha característica puede causar un overhead excesivo, especialmente en los casos en que el número de receptores crece (en el orden de miles de receptores). La razón de tal overhead es la necesidad de crear...

  17. Layered Multicast Encryption of Motion JPEG2000 Code Streams for Flexible Access Control

    Science.gov (United States)

    Nakachi, Takayuki; Toyoshima, Kan; Tonomura, Yoshihide; Fujii, Tatsuya

    In this paper, we propose a layered multicast encryption scheme that provides flexible access control to motion JPEG2000 code streams. JPEG2000 generates layered code streams and offers flexible scalability in characteristics such as resolution and SNR. The layered multicast encryption proposal allows a sender to multicast the encrypted JPEG2000 code streams such that only designated groups of users can decrypt the layered code streams. While keeping the layering functionality, the proposed method offers useful properties such as 1) video quality control using only one private key, 2) guaranteed security, and 3) low computational complexity comparable to conventional non-layered encryption. Simulation results show the usefulness of the proposed method.

  18. Realization of IPv6 Multicast Interworking between MANET and Fixed Networks

    Institute of Scientific and Technical Information of China (English)

    WANG Liang-you

    2003-01-01

    Nowadays, more and more attention is paid to the Mobile Ad hoc Network (MANET) because of its flexibility. To provide Internet access for MANET, the interworking mechanism between MANET and IP based fixed network is needed, which has become a vivid research area. However, so far, little work has been done to connect the multicast protocols on both sides so that users can access multicast services on either side. In this paper, a so-called Modified MLD (M.MLD) is proposed as a solution to IPv6 multicast interworking between MANET and fixed networks.

  19. QoS Multicast Routing Based on Ant Algorithm in Internet

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In this paper, based on ant-algorithm, we propose a QoS multicast routing scheme in Internet. We first describe ant-algorithm model and give ant-network model, then present an approach using ant-algorithm to optimize the multicast routes with QoS constaints. Finally, simulations has been made to show the efficiency of the approach in the environment of OPNET simulation software, and the simulation results show that the proposed approach can find the best optimal multicast routes which can satisfy the delay-bounded requirement and avoid congested nodes as soon as possible.

  20. Dynamic Multicast Grouping Approach in HLA-Based Distributed Interactive Simulation

    Institute of Scientific and Technical Information of China (English)

    DAI Zhong-jian; HOU Chao-zhen

    2005-01-01

    In order to improve the efficiency of data distributed management service in distributed interactive simulation based on high level architecture (HLA) and to reduce the network traffic and save the system resource, the approaches of multicast grouping in HLA-based distributed interactive simulation are discussed. Then a new dynamic multicast grouping approach is proposed. This approach is based on the current publication and subscription region in the process of simulation. The results of simulation experiment show that this approach can significantly reduce the message overhead and use fewer multicast groups.

  1. Core Placement Algorithm for Multicast Routing with QoS Requirements

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Differing from the source-oriented algorithms, the Core-Based Tree (CBT) multicast routing architecture establishes a single shared tree for multiple connections on a multicast group, which results in higher ratio of network resources utilization. In alluding to the problem of Core Placement, we propose a simple method (QOCP) to locate an optimal core node, which can minimize the multicast delay and inter-destination delay variation simultaneously. The simulation results show that our method is very effective, and outperforms the other algorithms studied in this paper.

  2. Explicit Rate Adjustment (ERA: Responsiveness, Network Utilization Efficiency and Fairness for Layered Multicast

    Directory of Open Access Journals (Sweden)

    Somnuk PUANGPRONPITAG

    2005-08-01

    Full Text Available To provide layered multicast with responsiveness, efficiency in network utilization, scalability and fairness (including inter-protocol fairness, intra-protocol fairness, intra-session fairness and TCP-friendliness for layered multicast, we propose in this paper a new multicast congestion control, called Explicit Rate Adjustment (ERA. Our protocol uses an algorithm relying on TCP throughput equation and Packet-bunch Probe techniques to detect optimal bandwidth utilization; then adjusts the reception rate accordingly. We have built ERA into a network simulator (ns2 and demonstrate via simulations that the goals are reached.

  3. Integer-Linear-Programing Optimization in Scalable Video Multicast with Adaptive Modulation and Coding in Wireless Networks

    Directory of Open Access Journals (Sweden)

    Dongyul Lee

    2014-01-01

    Full Text Available The advancement in wideband wireless network supports real time services such as IPTV and live video streaming. However, because of the sharing nature of the wireless medium, efficient resource allocation has been studied to achieve a high level of acceptability and proliferation of wireless multimedia. Scalable video coding (SVC with adaptive modulation and coding (AMC provides an excellent solution for wireless video streaming. By assigning different modulation and coding schemes (MCSs to video layers, SVC can provide good video quality to users in good channel conditions and also basic video quality to users in bad channel conditions. For optimal resource allocation, a key issue in applying SVC in the wireless multicast service is how to assign MCSs and the time resources to each SVC layer in the heterogeneous channel condition. We formulate this problem with integer linear programming (ILP and provide numerical results to show the performance under 802.16 m environment. The result shows that our methodology enhances the overall system throughput compared to an existing algorithm.

  4. Integer-linear-programing optimization in scalable video multicast with adaptive modulation and coding in wireless networks.

    Science.gov (United States)

    Lee, Dongyul; Lee, Chaewoo

    2014-01-01

    The advancement in wideband wireless network supports real time services such as IPTV and live video streaming. However, because of the sharing nature of the wireless medium, efficient resource allocation has been studied to achieve a high level of acceptability and proliferation of wireless multimedia. Scalable video coding (SVC) with adaptive modulation and coding (AMC) provides an excellent solution for wireless video streaming. By assigning different modulation and coding schemes (MCSs) to video layers, SVC can provide good video quality to users in good channel conditions and also basic video quality to users in bad channel conditions. For optimal resource allocation, a key issue in applying SVC in the wireless multicast service is how to assign MCSs and the time resources to each SVC layer in the heterogeneous channel condition. We formulate this problem with integer linear programming (ILP) and provide numerical results to show the performance under 802.16 m environment. The result shows that our methodology enhances the overall system throughput compared to an existing algorithm.

  5. Integer-Linear-Programing Optimization in Scalable Video Multicast with Adaptive Modulation and Coding in Wireless Networks

    Science.gov (United States)

    Lee, Chaewoo

    2014-01-01

    The advancement in wideband wireless network supports real time services such as IPTV and live video streaming. However, because of the sharing nature of the wireless medium, efficient resource allocation has been studied to achieve a high level of acceptability and proliferation of wireless multimedia. Scalable video coding (SVC) with adaptive modulation and coding (AMC) provides an excellent solution for wireless video streaming. By assigning different modulation and coding schemes (MCSs) to video layers, SVC can provide good video quality to users in good channel conditions and also basic video quality to users in bad channel conditions. For optimal resource allocation, a key issue in applying SVC in the wireless multicast service is how to assign MCSs and the time resources to each SVC layer in the heterogeneous channel condition. We formulate this problem with integer linear programming (ILP) and provide numerical results to show the performance under 802.16 m environment. The result shows that our methodology enhances the overall system throughput compared to an existing algorithm. PMID:25276862

  6. Routing of multimedia connections in hybrid networks

    Science.gov (United States)

    Koegel, John F.; Syta, Andrzej

    1993-02-01

    The prevailing vision for next generation multimedia communication systems is a digital one. However, we anticipate a transitional period in which hybrid networks involving both analog and digital technology will coexist. These analog facilities will include crossbar audio-video switches, CATV distribution systems, and dedicated lines. For some scale of use, these facilities may offer economies for connectivity to conventional analog video equipment. We are interested in connection routing that will be needed in such hybrid networks for services including video conferencing and broadcast results. The routing problem in such topologies resembles but is not identical to that found in telephone systems because of the presence of broadcast connections. We discuss representative topologies, review related work, and describe algorithms and simulation results. In addition we describe a hybrid system that we have implemented in our research lab which involves several A/V switches, CATV channels, digital video on a LAN, and a point-to-point link to an offsite conference area.

  7. Semantic multimedia analysis and processing

    CERN Document Server

    Spyrou, Evaggelos; Mylonas, Phivos

    2014-01-01

    Broad in scope, Semantic Multimedia Analysis and Processing provides a complete reference of techniques, algorithms, and solutions for the design and the implementation of contemporary multimedia systems. Offering a balanced, global look at the latest advances in semantic indexing, retrieval, analysis, and processing of multimedia, the book features the contributions of renowned researchers from around the world. Its contents are based on four fundamental thematic pillars: 1) information and content retrieval, 2) semantic knowledge exploitation paradigms, 3) multimedia personalization, and 4)

  8. Capacity of a Class of Multicast Tree Networks

    CERN Document Server

    Lee, Si-Hyeon

    2010-01-01

    In this paper, a class of single-source multicast discrete memoryless relay networks having a tree topology is considered in which the root node is the source, each parent node in the graph has at most one noisy child node and any number of noiseless child nodes, and subsets of leaf nodes are destinations. For this class of multicast tree networks, lower and upper bounds on the capacity are presented and these two bounds are shown to meet when each set of nodes forming a destination is included in a disjoint subtree, which includes the single-destination case. For achievablity, a coding scheme is constructed where each noisy relay employs a combination of decode-and-forward (DF) and compress-and-forward (CF) and each noiseless relay performs random binning. In our coding scheme, codebook constructions and relay operations are independent for each node and do not depend on the network topology, which is a key ingredient of our achievability proof. We note that our result is the first to show that the combinati...

  9. Game and Balance Multicast Architecture Algorithms for Sensor Grid

    Science.gov (United States)

    Fan, Qingfeng; Wu, Qiongli; Magoulés, Frèdèric; Xiong, Naixue; Vasilakos, Athanasios V.; He, Yanxiang

    2009-01-01

    We propose a scheme to attain shorter multicast delay and higher efficiency in the data transfer of sensor grid. Our scheme, in one cluster, seeks the central node, calculates the space and the data weight vectors. Then we try to find a new vector composed by linear combination of the two old ones. We use the equal correlation coefficient between the new and old vectors to find the point of game and balance of the space and data factorsbuild a binary simple equation, seek linear parameters, and generate a least weight path tree. We handled the issue from a quantitative way instead of a qualitative way. Based on this idea, we considered the scheme from both the space and data factor, then we built the mathematic model, set up game and balance relationship and finally resolved the linear indexes, according to which we improved the transmission efficiency of sensor grid. Extended simulation results indicate that our scheme attains less average multicast delay and number of links used compared with other well-known existing schemes. PMID:22399992

  10. Abacus switch: a new scalable multicast ATM switch

    Science.gov (United States)

    Chao, H. Jonathan; Park, Jin-Soo; Choe, Byeong-Seog

    1995-10-01

    This paper describes a new architecture for a scalable multicast ATM switch from a few tens to thousands of input ports. The switch, called Abacus switch, has a nonblocking memoryless switch fabric followed by small switch modules at the output ports; the switch has input and output buffers. Cell replication, cell routing, output contention resolution, and cell addressing are all performed distributedly in the Abacus switch so that it can be scaled up to thousnads input and output ports. A novel algorithm has been proposed to resolve output port contention while achieving input and output ports. A novel algorithm has been proposed to reolve output port contention while achieving input buffers sharing, fairness among the input ports, and multicast call splitting. The channel grouping concept is also adopted in the switch to reduce the hardware complexity and improve the switch's throughput. The Abacus switch has a regular structure and thus has the advantages of: 1) easy expansion, 2) relaxed synchronization for data and clock signals, and 3) building the switch fabric using existing CMOS technology.

  11. Reliable and Energy Efficient Protocol for MANET Multicasting

    Directory of Open Access Journals (Sweden)

    Bander H. AlQarni

    2016-01-01

    Full Text Available A mobile ad hoc network (MANET consists of a self-configured set of portable mobile nodes without any central infrastructure to regulate traffic in the network. These networks present problems such as lack of congestion control, reliability, and energy consumption. In this paper, we present a new model for MANET multicasting called Reliable and Energy Efficient Protocol Depending on Distance and Remaining Energy (REEDDRE. Our proposal is based on a tone system to provide more efficiency and better performance, and it combines solutions over the Medium Access Control (MAC layer. The protocol consists of a new construction method for mobile nodes using a clustering approach that depends on distance and remaining energy to provide more stability and to reduce energy consumption. In addition, we propose an adjustment to the typical multicast flow by adding unicast links between clusters. We further present in our model a technique to provide more reliability based on a busy tone system (RMBTM to reduce excessive control overhead caused by control packets in error recovery. We simulate our proposal using OPNET, and the results show enhancement in terms of reliability, packet delivery ratio (PDR, energy consumption, and throughput.

  12. Verification and validation of a reliable multicast protocol

    Science.gov (United States)

    Callahan, John R.; Montgomery, Todd L.

    1995-01-01

    This paper describes the methods used to specify and implement a complex communications protocol that provides reliable delivery of data in multicast-capable, packet-switching telecommunication networks. The protocol, called the Reliable Multicasting Protocol (RMP), was developed incrementally by two complementary teams using a combination of formal and informal techniques in an attempt to ensure the correctness of the protocol implementation. The first team, called the Design team, initially specified protocol requirements using a variant of SCR requirements tables and implemented a prototype solution. The second team, called the V&V team, developed a state model based on the requirements tables and derived test cases from these tables to exercise the implementation. In a series of iterative steps, the Design team added new functionality to the implementation while the V&V team kept the state model in fidelity with the implementation through testing. Test cases derived from state transition paths in the formal model formed the dialogue between teams during development and served as the vehicles for keeping the model and implementation in fidelity with each other. This paper describes our experiences in developing our process model, details of our approach, and some example problems found during the development of RMP.

  13. IPTV multicast with peer-assisted lossy error control

    Science.gov (United States)

    Li, Zhi; Zhu, Xiaoqing; Begen, Ali C.; Girod, Bernd

    2010-07-01

    Emerging IPTV technology uses source-specific IP multicast to deliver television programs to end-users. To provide reliable IPTV services over the error-prone DSL access networks, a combination of multicast forward error correction (FEC) and unicast retransmissions is employed to mitigate the impulse noises in DSL links. In existing systems, the retransmission function is provided by the Retransmission Servers sitting at the edge of the core network. In this work, we propose an alternative distributed solution where the burden of packet loss repair is partially shifted to the peer IP set-top boxes. Through Peer-Assisted Repair (PAR) protocol, we demonstrate how the packet repairs can be delivered in a timely, reliable and decentralized manner using the combination of server-peer coordination and redundancy of repairs. We also show that this distributed protocol can be seamlessly integrated with an application-layer source-aware error protection mechanism called forward and retransmitted Systematic Lossy Error Protection (SLEP/SLEPr). Simulations show that this joint PARSLEP/ SLEPr framework not only effectively mitigates the bottleneck experienced by the Retransmission Servers, thus greatly enhancing the scalability of the system, but also efficiently improves the resistance to the impulse noise.

  14. Internet multimedia and search mining

    CERN Document Server

    Hua, Xian-Sheng

    2013-01-01

    With the explosion of video and image data available on the Internet, desktops and mobile devices, multimedia search has gained immense importance. This is the first reference book on the subject of internet multimedia search and mining and it will be extremely useful for graduates, researchers and working professionals in the field of information technology and multimedia content analysis.

  15. Optimización multiobjetivo para enrutamiento multicast en overlay networks utilizando algoritmos evolutivos Multiobjective Optimization for Multicast Routing in Overlay Networks using Evolutionary Algorithms

    Directory of Open Access Journals (Sweden)

    Juan Carlos Montoya M.

    2008-06-01

    Full Text Available Multicast juega un papel muy importante para soportar una nueva generación de aplicaciones. En la actualidad y por diferentes razones, técnicas y no técnicas, multicast IP no ha sido totalmente adoptado en Internet. Durante los últimos a˜nos, un área de investigación activa es la de implementar este tipo de tráfico desde la perspectiva del nivel de aplicación, donde la funcionalidad de multicast no es responsabilidad de los enrutadores sino de los hosts, a lo que se le conoce como Multicast Overlay Network (MON. En este artículo se plantea el enrutamiento en MON como un problema de Optimización Multiobjetivo (MOP donde se optimizan dos funciones: 1 el retardo total extremo a extremo del árbol multicast, y 2 la máxima utilización de los enlaces. La optimización simultánea de estas dos funciones es un problema NP completo y para resolverlo se propone utilizar Algoritmos Evolutivos Multiobjetivos (MOEA, específicamente NSGAIMulticast plays an important role in supporting a new generation of applications. At present and for different reasons, technical and non–technical, multicast IP hasn’t yet been totally adopted for Internet. During recent years, an active area of research is that of implementing this kind of traffic in the application layer where the multicast functionality isn´t a responsibility of the routers but that of the hosts, which we know as Multicast Overlay Networks (MON. In this article, routing in an MON is put forward as a multiobjective optimization problem (MOP where two functions are optimized: 1 the total end to end delay of the multicast tree and 2 the maximum link utilization. The simultaneous optimization of these two functions is an NP–Complete problem and to solve this we suggest using Multiobjective Evolutionary Algorithms (MOEA, specifically NSGA–II.

  16. Performance analysis of hybrid WDM-OTDM optical multicast overlay system employing 120 Gbps polarization and subcarrier multiplexed unicast signal with 40 Gbps multicast signal

    Science.gov (United States)

    Singh, Sukhbir; Singh, Surinder

    2017-02-01

    In this paper, we have propose and investigated the performance of hybrid WDM-OTDM optical multicast overlay system which employs 120 Gbps unicast and 40 Gbps multicast data operating over SMF+DCF and amplifier link in C-band. The polarization and subcarrier multiplexed modulation formats are used to obtain 120 Gbps unicast data and DPSK (differential phase shift keying) modulation format for 40 Gbps multicast data transmission. In multicast operation, DPSK data is superimposed on to multiplexed unicast data channels. The impact of extinction ratio, input power and transmission distance on the performance of proposed system in terms of output optical power, BER and Q-factor has been investigated for both unicast and multicast data. We have also concluded that polarization and subcarrier multiplexed modulation formats are promising option to increase per channel capacity and less vulnerable to CD and PMD. In addition, the proposed system using hybrid modulation techniques offers higher bandwidth utilization efficiency at higher per channel data rate than conventional modulation formats.

  17. Corrections to "Connectivity-Based Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs"

    Directory of Open Access Journals (Sweden)

    Choi Woo-Yong

    2010-01-01

    Full Text Available We have found the errors in the throughput formulae presented in our paper "Connectivity-based reliable multicast MAC protocol for IEEE 802.11 wireless LANs". We provide the corrected formulae and numerical results.

  18. Reliable Multicast MAC Protocol for IEEE 802.11 Wireless LANs with Extended Service Range

    Science.gov (United States)

    Choi, Woo-Yong

    2011-11-01

    In this paper, we propose the efficient reliable multicast MAC protocol by which the AP (Access Point) can transmit reliably its multicast data frames to the recipients in the AP's one-hop or two-hop transmission range. The AP uses the STAs (Stations) that are directly associated with itself as the relays for the data delivery to the remote recipients that cannot be reached directly from itself. Based on the connectivity information among the recipients, the reliable multicast MAC protocol optimizes the number of the RAK (Request for ACK) frame transmissions in a reasonable computational time. Numerical examples show that our proposed MAC protocol significantly enhances the MAC performance compared with the BMMM (Batch Mode Multicast MAC) protocol that is extended to support the recipients that are in the AP's one-hop or two-hop transmission range in IEEE 802.11 wireless LANs.

  19. A New Scheme for MPLS Supporting IP Multicast and Its Validation

    Institute of Scientific and Technical Information of China (English)

    LONG Keping; ZHANG Zhongshan; WANG Wendong; CHENG Shiduan

    2001-01-01

    MPLS that combines the flexibility ofLayer3 routing with QoS supporting of Layer2 switch-ing is being widely developed. Unfortunately, exist-ing MPLS specification can only support unicast well,but is lack of supporting multicast. The main dif-ficulty of MPLS supporting multicast is the bindinglabels to multicast FEC. This paper mainly presentsa new scheme that MPLS supports IP multicast rout-ing protocol. In the proposed mechanism, the labeldistribution is triggered by traffic and not by controlmessages. This scheme makes the network's scalabil-ity and dynamic characteristic better than the schemewhose label distribution is triggered by control mes-sages. The simulation results validate that this schemecan work well both in normal network and in the con-dition of higher link-loss-rate.

  20. A Genetic Algorithm for Delay-constrained Least-cost Multicast Routing

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The delay-constrained least-cost multicast routing problem is introduced and then a related genetic algorithm is proposed. Finally, simulation results are shown to prove that the genetic algorithm is fast and effective.

  1. Performance Analysis of QoS Multicast Routing in Mobile Ad Hoc Networks Using Directional Antennas

    Directory of Open Access Journals (Sweden)

    Yuan Li

    2010-12-01

    Full Text Available in this paper, a quality of service (QoS multicast routing protocol in mobile ad hoc networks (MANETs by using directional antennas has been presented. Many important applications, such as audio/video conferencing, require the quality of service guarantee. Directional antenna technology provides the capability for considerable increase in spatial reuse, which increases the efficiency of communication. This paper studies TDMA-based timeslot allocation and directional antennas, and presents an effective algorithm for calculating bandwidth of a multicast tree. We also propose a novel on-demand QoS multicasting routing algorithm in TDMA-based mobile ad hoc networks using directional antennas. The simulation result shows the performance of this QoS multicast routing algorithm in TDMA-based mobile ad hoc networks using directional antennas.

  2. Relay Ability Estimation and Topology Control Using Multidimensional Context Parameters for Mobile P2P Multicast

    Directory of Open Access Journals (Sweden)

    Kubo Hiroyuki

    2011-01-01

    Full Text Available We focus on mobile P2P multicast, in which mobile end nodes not only act as receivers but also relay the received stream forward to others. In mobile P2P multicast, negative effects caused by the change of available bandwidth and the disconnection of mobile nodes are propagated to the downstream nodes. To solve this problem, we developed a novel node-allocation framework using the multidimensional context parameters of each mobile node, which include available bandwidth, disconnection rate, and the remaining battery capacity. Considering the significance of each parameter, our method integrates these parameters into a single parameter called relay ability. Taking the relay ability into account, each node is allocated to the multicast topology to minimize the negative effects mentioned above. To test our method, we applied our framework to conventional P2P multicast topology and show the results from comparative evaluations through computer simulation.

  3. A Hybrid Multicast-Unicast Infrastructure for Efficient Publish-Subscribe in Enterprise Networks

    CERN Document Server

    Bickson, Danny; Naaman, Nir; Tock, Yoav

    2009-01-01

    One of the main challenges in building a large scale publish-subscribe infrastructure in an enterprise network, is to provide the subscribers with the required information, while minimizing the consumed host and network resources. Typically, previous approaches utilize either IP multicast or point-to-point unicast for efficient dissemination of the information. In this work, we propose a novel hybrid framework, which is a combination of both multicast and unicast data dissemination. Our hybrid framework allows us to take the advantages of both multicast and unicast, while avoiding their drawbacks. We investigate several algorithms for computing the best mapping of publishers' transmissions into multicast and unicast transport. Using extensive simulations, we show that our hybrid framework reduces consumed host and network resources, outperforming traditional solutions. To insure the subscribers interests closely resemble those of real-world settings, our simulations are based on stock market data and on recor...

  4. Multimedia communications: architectural alternatives

    Science.gov (United States)

    McGarty, Terrence P.; Treves, S. T.

    1992-03-01

    Multimedia communications systems are a combination of human interfaces and end users interacting with multimedia data bases and highly disparate but interconnected communications networks. This paper discusses several architectural alternatives and system requirements that will assist in the design and development of MMCS in actual environments. The approaches taken in this paper are based upon the development of such systems in both medical and printing and publishing environments. This paper develops several key concepts as how best to define and structure data in a multimedia environment, how best to integrate the communications elements, and how best to permit the maximum flexibility to the end user to utilize the system's capabilities in the context of a fully conversational environment.

  5. Multicast Routing with End-to-End Delay forNumber of Tardy Member of Multicast Group

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xianwei; CHEN Changjia; ZHU Gang

    2001-01-01

    The problem of constructing multi-cast trees to meet the quality of service requirementsof real-time interactive applications operating in high-speed packet-switched environments is presented.Inparticular,the new concept of the delay is redefined,that is,the concepts of delay of the link (or the path)and delay of destination are distinguished.Routineend-to-end delay is defined as "deadline delay" or"bounded delay" and the delay of number of tardymember in this paper is defined as "slack delay".Theslack delay of the destination refers to the feature thatthe accumulated delay from the source to any destina-tion along the tree may exceed the value of slack delay.The problem of determining such a constrained tree isNP-complete.A heuristic presented demonstrates agood average case behavior in terms of the two objec-tives.We also show that it is possible to dynamicallyreorganize the initial tree in response to changes in thedestination set,in a way that is minimally disruptiveto the multicast session.

  6. Fast Multicast on Multistage Interconnection Networks Using Multi-Head Worms

    Institute of Scientific and Technical Information of China (English)

    WANG Xiaodong; XU Ming; ZHOU Xingming

    1999-01-01

    Abstract This paper proposes a new approach forimplementing fast multicast on multistage interconnection networks (MINs)with multi-head worms. For an MIN with n stages of k×k switches,a singlemulti-head worm can cover an arbitrary set of destinations with asingle communication start-up. Compared with schemes using unicastmessages, this approach reduces multicast latency significantly andperforms better than multi-destination worms.

  7. A Multicast Protocol Utilizing On-demand Routing Strategy for MPRN

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper proposes a multicast protocol utilizing ondemand routing strategy for mobile packet radio network. It does not maintain permanent route tables with full topological views. Instead, multicast senders apply on-demand procedures to dynamically discover routes and build forwarding group in this protocol. The data packets are propagated by each forwarding group member via scoped flooding, so the protocol can reduce network bandwidth overhead and avoid the propagation of potentially large routing updates throughout the network.

  8. Pseudo-Cycle-Based Multicast Routing in Wormhole-Routed Networks

    Institute of Scientific and Technical Information of China (English)

    SONG JianPing (宋建平); HOU ZiFeng (侯紫峰); XU Ming (许铭)

    2003-01-01

    This paper addresses the problem of fault-tolerant multicast routing in wormholerouted multicomputers. A new pseudo-cycle-based routing method is presented for constructing deadlock-free multicast routing algorithms. With at most two virtual channels this technique can be applied to any connected networks with arbitrary topologies. Simulation results show that this technique results in negligible performance degradation even in the presence of a large number of faulty nodes.

  9. A subtree-based approach to failure detection and protection for multicast in SDN#

    Institute of Scientific and Technical Information of China (English)

    Vignesh RENGANATHAN RAJA; Chung-Horng LUNG; Abhishek PANDEY; Guo-ming WEI; Anand SRINIVASAN

    2016-01-01

    Software-defined networking (SDN) has received tremendous attention from both industry and academia. The cen-tralized control plane in SDN has a global view of the network and can be used to provide more effective solutions for complex problems, such as traffic engineering. This study is motivated by recent advancement in SDN and increasing popularity of mul-ticasting applications. We propose a technique to increase the resiliency of multicasting in SDN based on the subtree protection mechanism. Multicasting is a group communication technology, which uses the network infrastructure efficiently by sending the data only once from one or multiple sources to a group of receivers that share a common path. Multicasting applications, e.g., live video streaming and video conferencing, become popular, but they are delay-sensitive applications. Failures in an ongoing mul-ticast session can cause packet losses and delay, which can significantly affect quality of service (QoS). In this study, we adapt a subtree-based technique to protect a multicast tree constructed for OpenFlow switches in SDN. The proposed algorithm can detect link or node failures from a multicast tree and then determines which part of the multicast tree requires changes in the flow table to recover from the failure. With a centralized controller in SDN, the backup paths can be created much more effectively in com-parison to the signaling approach used in traditional multiprotocol label switching (MPLS) networks for backup paths, which makes the subtree-based protection mechanism feasible. We also implement a prototype of the algorithm in the POX controller and measure its performance by emulating failures in different tree topologies in Mininet.

  10. Exploring Multimedia Web Conferencing

    Directory of Open Access Journals (Sweden)

    Ana-Maria SUDUC

    2009-01-01

    Full Text Available Internet changed the perspective on meetings and also on decision making processes. Virtualization of meetings has become a common way for collaboration among employees, customers, partners, trainees and trainers, etc. Web conferencing allows the collaboration between teams' members to achieve common goals. Without the need of travelling and meeting organization, the web conferencing applications permit the participation of people from different location. Web conferencing applications are multimedia systems that allow various remote collaborations with multiple types of resources. The paper presents an exploratory study on multimedia web conferencing systems, its advantages and disadvantages and also a use case, meant to highlight several of this technology benefits and problems.

  11. Brief Announcement: Decentralized Construction of Multicast Trees Embedded into P2P Overlay Networks based on Virtual Geometric Coordinates

    CERN Document Server

    Andreica, Mugurel Ionut; Sambotin, Ana-Delia; Tapus, Nicolae; 10.1145/1835698.1835766

    2010-01-01

    In this paper we consider the problem of efficiently constructing in a fully distributed manner multicast trees which are embedded into P2P overlays using virtual geometric node coordinates. We consider two objectives: to minimize the number of messages required for constructing a multicast tree by using the geometric properties of the P2P overlay, and to construct stable multicast trees when the lifetime durations of the peers are known.

  12. Analysis of satellite broadcasting systems for digital television

    Science.gov (United States)

    de Gaudenzi, Riccardo; Elia, Carlo; Viola, Roberto

    1993-01-01

    This paper introduces the new concept of digital direct satellite broadcasting (D-DBS), which allows unprecedented flexibility by providing a large number of audio-visual services. The concept elaborated on in this paper assumes an information rate of about 40 Mb/s, which is compatible with practically all present-day transponders. After discussion of the general system concept, the optimization procedure is introduced and results of the transmission system optimization are presented. Channel distortion and uplink/downlink interference effects are taken into account by means of a time domain system computer simulation approach. It is shown, by means of link budget analysis, how a medium power direct-to-home TV satellite can provide multimedia services to users equipped with small (60 cm) dish antennas.

  13. Broadcast and Aggregation in BBC

    DEFF Research Database (Denmark)

    Hüttel, Hans; Kiilerich Pratas, Nuno

    2015-01-01

    In this paper we introduce a process calculus BBC that has both forms of communication. For both many-to-one and one-to-many communication, it is often a natural assumption that communication is bounded; this reflects two distinct aspects of the limitations of a medium. In the case of broadcast......, the bound limits the number of possible recipients of a message. In the case of collection, the bound limits the number of messages that can be received. For this reason, BBC uses a notion of bounded broadcast and collection. Moreover, the syntax of the calculus introduces an explicit notion of connectivity...

  14. Minimum-Energy All-to-All Multicasting in Multi-hop Wireless Networks

    CERN Document Server

    Han, Kai; Luo, Jun

    2011-01-01

    Designing energy-efficient all-to-all multicasting protocols is of of great importance for multi-hop wireless networks such as wireless sensor networks and wireless ad hoc networks. In an all-to-all multicast session, there exists a set of wireless destination nodes, and each destination node needs to send some data packets to all other destination nodes. We consider the problem of building a shared multicast tree spanning the destination nodes such that the total energy consumption of realizing an all-to-all multicast session using the shared multicast tree is minimized. Since building such a multicast tree has been proved to be NP-complete, we provide both centralized and distributed approximation algorithms with provable approximation ratios for it. When the transmission power of each wireless node is fixed, our centralized and distributed algorithms have the approximation ratios of $4ln(\\Delta+1)+7$ and 13, respectively, where $\\Delta$ is the maximum node degree in the network. When the transmission power...

  15. Distributed and Location-Based Multicast Routing Algorithms for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Hakki Bagci

    2009-01-01

    Full Text Available Multicast routing protocols in wireless sensor networks are required for sending the same message to multiple different destinations. In this paper, we propose two different distributed algorithms for multicast routing in wireless sensor networks which make use of location information of sensor nodes. Our first algorithm groups the destination nodes according to their angular positions and forwards the multicast message toward each group in order to reduce the number of total branches in multicast tree which also reduces the number of messages transmitted. Our second algorithm calculates an Euclidean minimum spanning tree at the source node by using the positions of the destination nodes. The multicast message is forwarded to destination nodes according to the calculated MST. This helps in reducing the total energy consumed for delivering the message to all destinations by decreasing the number of total transmissions. Evaluation results show that the algorithms we propose are scalable and energy efficient, so they are good candidates to be used for multicasting in wireless sensor networks.

  16. ARRANGING MULTICAST FORWARDING TABLE IN CLASS SEQUENCE IN TERNARY-CAM FOR LINE-SPEED LOOKUP

    Institute of Scientific and Technical Information of China (English)

    Li Yufeng; Qiu Han; Lan Julong; Wang Binqiang

    2009-01-01

    PIM-SM (Protocol Independent Multicast-Sparse Mode) is a main multicast routing protocol in the IPv6 (Internet Protocol version 6). It can use either a shared tree or a shortest path tree to deliver data packets, consequently the multicast IP lookup engine requires, in some cases, two searches to get a correct lookup result according to its multicast forwarding rule, and it may result in a new requirement of doubling the lookup speed of the lookup engine. The ordinary method to satisfy this requirement in TCAM (Ternary Content Addressable Memory) based lookup engines is to exploit parallelism among multiple TCAMs. However, traditional parallel methods always induce more resources and higher design difficulty. We propose in this paper a novel approach to solve this problem. By arranging multicast forwarding table in class sequence in TCAM and making full use of the intrinsic characteristic of the TCAM, our approach can get the right lookup result with just one search and a single TCAM, while keeping the hardware of lookup engine unchanged. Experimental results have shown that the approach make it possible to satisfy forwarding IPv6 multicast packets at the full link rate of 20 Gb/s with just one TCAM with the current TCAM chip.

  17. 75 FR 49528 - Freescale Semiconductor, Inc., Networking and Multimedia Group (“NMG”) Excluding the Multimedia...

    Science.gov (United States)

    2010-08-13

    ... Employment and Training Administration Freescale Semiconductor, Inc., Networking and Multimedia Group (``NMG..., applicable to workers of Freescale Semiconductor, Inc., Networking and Multimedia Group (``NMG''), excluding... Semiconductor, Inc., Networking and Multimedia Group (``NMG''), excluding the Multimedia Applications...

  18. MULTIMEDIA TECHNOLOGIES IN PRIMARY SCHOOL

    Directory of Open Access Journals (Sweden)

    Vira M. Andriievska

    2010-08-01

    Full Text Available In the article it has been analysed a role of multimedia technologies in primary school. On the basis of conducted analysis of different approaches to interpretation of “multimedia technologies” concept the context of this term is summarized. It is grounded an expedience of the use of multimedia in primary school practice as well as the types of multimedia technologies are selected. The factors which must be taken into account during organization the work of primary school pupils with programmatic facilities such as features of psychophysiologic development of primary school pupils and their educational-cognitive activity; didactics potential of multimedia technologies; features of the use of multimedia in studies; requirements to introduction of multimedia in the educational process of primary school are considered.

  19. On-demand data broadcast scheduling based on AHP and GRA methods in wireless broadcast/UMTS integrated systems

    Institute of Scientific and Technical Information of China (English)

    WANG Hui; LI Chun; JI Yang

    2007-01-01

    The increasing demand for interactive mobile multimedia service is causing the integration of 3rd generation (3G) cellular systems and wireless broadcast systems. The key challenge is to support data dissemination with low response time, request drop rate, and the unfairness of request drop. This article proposes a novel scheduling algorithm called DAG (on-demand scheduling utilizing analytic hierarchy process (AHP) and grey relational analysis (GRA)), which takes multiple factors-waiting time, number of active requests, deadline-into consideration, and models the data scheduling process as a multiple factors' decision-making and best option-selecting process. The proposed approach comprises two parts. The first part applies AHP to decide the relative weights of multiple decision factors according to user requests, while the second adopts GRA to rank the data item alternatives through the similarity between each option and the ideal option. Simulation results are presented to demonstrate that DAG performs well in the multiple criterions mentioned above.

  20. Broadcasting Stations of the World; Part II. Amplitude Modulation Broadcasting Stations According to Frequency.

    Science.gov (United States)

    Foreign Broadcast Information Service, Washington, DC.

    This second part of "Broadcasting Stations of the World", which lists all reported radio broadcasting and television stations with the exception of those in the United States which broadcast on domestic channels, covers amplitude modulation broadcasting stations according to frequency in ascending order. Information included covers call letters,…

  1. Broadcasting Stations of the World; Part I. Amplitude Modulation Broadcasting Stations According to Country and City.

    Science.gov (United States)

    Foreign Broadcast Information Service, Washington, DC.

    This first part of "Broadcasting Stations of the World", which lists all reported radio broadcasting and television stations, with the exception of those in the United States which broadcast on domestic channels, covers amplitude modulation broadcasting stations. Information is indexed alphabetically by country and city. Within a city, stations…

  2. Broadcasting Stations of the World; Part III. Frequency Modulation Broadcasting Stations.

    Science.gov (United States)

    Foreign Broadcast Information Service, Washington, DC.

    This third part of "Broadcasting Stations of the World", which lists all reported radio broadcasting and television stations, with the exception of those in the United States which broadcast on domestic channels, covers frequency modulation broadcasting stations. It contains two sections: one indexed alphabetically by country and city, and the…

  3. Modeling Distributed Multimedia Synchronization with DSPN

    Institute of Scientific and Technical Information of China (English)

    宋军; 顾冠群

    1998-01-01

    Multimedia synchronization is the essential technology for the integration of multimedia in distributed multimedia systems.The multimedia synchronization model has been recognized by many researchers as a premise of the implementation of multimedia synchronization.In distributed multimedia systems,the characteristic of multimedia synchronization is dynamic,and the key medium has the priority in multimedia synchronization.The previously proposed multimedia synchronization models cannot meet these requirements.So a new multimedia dynamic synchronization model-DSPN,based on the timed Petri-net has been designed in this paper.This model can not only let the distributed multimedia system keep multimedia synchronization in a more precise and effective manner according to the runtime situation of the system,but also allow the user to interact with the presentation of multimedia.

  4. Multimedia Databases in Perspective

    NARCIS (Netherlands)

    Apers, Peter M.G.; Blanken, Henk; Houtsma, M.A.W.; Unknown, [Unknown

    1997-01-01

    This volume provides much-needed coverage of the technical background to the development of multimedia applications. Based on an advanced summer school run by the University of Twente, each chapter is written by an expert in a particular topic, including enabling technologies, operating systems, ind

  5. Storyboarding Multimedia Interactions.

    Science.gov (United States)

    Martin, Linda C.

    2000-01-01

    Understanding how to include interactivity when designing multimedia-based training (MBT) storyboards is a major key for a successful MBT. Discusses the basic formats of interactions and when to use each format. Describes how to storyboard and areas to address, including: the display area, prompts, branching, programming and graphics notes,…

  6. Creating Meaningful Multimedia Presentations

    NARCIS (Netherlands)

    Hardman, L.; Ossenbruggen, J.R. van

    2006-01-01

    Finding relevant information is one step in the chain of understanding information. Presenting material to a user in a suitable way is a further step. Our research focuses on using semantic annotations of multimedia elements to increase the ”presentability” of retrieved info

  7. The Multimedia Challenge.

    Science.gov (United States)

    Penuel, William R.; Means, Barbara; Simkins, Michael

    2000-01-01

    Teachers implementing a local history project in Belmont, California, had help from a federally funded technology innovation challenge grant: the Challenge 2000 Multimedia Project. Sponsored by a Silicon Valley school-business partnership, the initiative illustrates how technology can transform classroom learning while supporting instructional…

  8. Construction on the Broadcasting of Cultural Value

    Institute of Scientific and Technical Information of China (English)

    Ai Xu

    2011-01-01

    Broadcast host responsible transmission of information, expression of emotion and preserving culture. Construction of broadcasting cultural value will raise the cultural character of the electronic medium itself, provide spiritual power of the people's needs, enhancing the cultural influence of broadcasting on audiences.

  9. Southeast Asian Broadcasting: The Emergence of Thailand.

    Science.gov (United States)

    Anatol, Karl W.; Bittner, John R.

    The historical development and evolution of broadcasting in Thailand, from its beginning in 1919, is narrated. Governmental control of broadcasting is discussed briefly, and the development of Southeast Asia's first television station, Thai Television Channel 4, is also surveyed. Today, radio broadcasting in Thailand utilizes A.M., F.M., and F.M.…

  10. 47 CFR 73.14 - AM broadcast definitions.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false AM broadcast definitions. 73.14 Section 73.14 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES AM Broadcast Stations § 73.14 AM broadcast definitions. AM broadcast band. The band of frequencies extending...

  11. 47 CFR 73.128 - AM stereophonic broadcasting.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false AM stereophonic broadcasting. 73.128 Section 73.128 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES AM Broadcast Stations § 73.128 AM stereophonic broadcasting. (a) An Am broadcast...

  12. Survey on Broadcasting in VANETs

    Directory of Open Access Journals (Sweden)

    Shereen A.M. Ahmed

    2014-05-01

    Full Text Available This study aims to evaluate, categorize and compare the Vehicular Ad-hoc Network (VANET broadcasting protocols. Massive amount of VANET broadcasting protocols have been proposed in the literature. Aiming efficiency, reliability, scalability and reach-ability each of them adopts certain techniques to provide a certain level of functionality. This study distinguishes the VANET routing protocols in several categorizes according to the applications it may serve. By focusing into broadcasting protocols, the study further divides the reviewed algorithms according to the techniques they used to initiate the communication, which would be either through beaconing, handshaking, or instant broadcasting. These protocols are further classified according to the criteria that have been used to select the next forwarder. The criteria usually influenced by the targeted performance of the technique. Such criteria may include furthest node from the sender, the node with the best link quality, endanger nodes, nodes with high probability of forwarding and backbone nodes. Performance metrics that are used for quantitative evaluation are suggested.

  13. Lossless Compression of Broadcast Video

    DEFF Research Database (Denmark)

    Martins, Bo; Eriksen, N.; Faber, E.

    1998-01-01

    We investigate several techniques for lossless and near-lossless compression of broadcast video.The emphasis is placed on the emerging international standard for compression of continous-tone still images, JPEG-LS, due to its excellent compression performance and moderatecomplexity. Except for one...

  14. MULTICAST-SUPPORTED FAST HANDOVER FOR Proxy Mobile IPv6

    Directory of Open Access Journals (Sweden)

    V. Berlin Hency

    2013-01-01

    Full Text Available Proxy Mobile IPv6 is a network-based mobility management protocol which is attractive as it does not require the participation of mobile nodes in mobility-related signaling. Unlike the host based approaches like Mobile IPv6, in PMIPv6 the Mobility Access Gateway (MAG is responsible for tracking the movements of Mobile Node (MN and to initiate the handover process. In this study, a novel method of multicasting the data packets to both the previous and the new MAGs by Local Mobility Anchor (LMA during the handover process is proposed. The experimental results show that the handover delay is greatly reduced when compared to the existing approaches and the packet loss during the handover process is reduced.

  15. FAIRNESS OF SHARING PROTECTION FOR MULTICAST IN WDM NETWORKS

    Institute of Scientific and Technical Information of China (English)

    Li Yonggang; Jin Yaohui; Li Lemin

    2008-01-01

    In this paper,the sharing schemes of multicast in survivable Wavelength-Division Multiplexed (WDM) networks are studied and the concept of Shared Risk Link Group (SRLG) is considered.While the network resources are shared by the backup paths,the sharing way is possible to make the backup paths selfish. This selfishness leads the redundant hops of the backup route and a large number of primary lightpaths to share one backup link. The sharing schemes,especially,the self-sharing and cross-sharing,are investigated to avoid the selfishness when computing the backup light-tree. In order to decrease the selfishness of the backup paths,it is important to make the sharing links fair to be used.There is a trade-off between the self-sharing and cross-sharing,which is adjusted through simulation to adapt the sharing degree of each sharing scheme and save the network resources.

  16. A Fast Handover Scheme for Multicasting in IPv6 based Mobile Ad hoc Networks

    Directory of Open Access Journals (Sweden)

    H. Parveen Sultana

    2011-01-01

    Full Text Available Abstract: Problem statement: In the previous researches, steps were taken to resolve the problems of multicasting, after several discussions. Actually these issues were raised, while multicasting packets from Internet Protocol (IP to Mobile Nodes (MN. On the other hand, there is very little concern about the problem of packet loss reduction. Sometimes the occurrence of multicast service chaos is ignored during handovers. Therefore in this study it has been tried to explain the optimal multicast technique for Mobile IPv6 (MIPv6 to diminish the required amendment to the existing fast handover. Approach: An alternate method is suggested in Fast handover for MIPv6 (FMIPv6 to lessen the packet losses during handovers, before tunneling. Based on the qualities of the multicast subscription techniques for the Mobile IPv6 (MIPv6, multicast upholds method for FMIPv6. MIPv6 in general comprise two types of multicasting techniques, which are related to Home Agent (HA and Foreign Agent (FA. These techniques help the MN to obtain the packets in roaming location referred as Foreign Network (FN, which is being forwarded by the Core Network (CN. But due to the handover latency problem MN have to experience packet loss while switching between any two Access Routers (AR. A protocol has been designed to conquer the issue of packet loss in MIPv6. Results and Conclusion: This protocol can be used during joining process in MIPv6 before tunneling to eliminate the IP connectivity time. This implementation allows a mobile node to be connected more quickly at a fresh point of connection, when that mobile node moves with less packet losses.

  17. Multimedia encryption and watermarking encryption and watermarking

    CERN Document Server

    Furht, Borko; Socek, Daniel

    2006-01-01

    ""Multimedia Encryption and Watermarking"" presents a comprehensive survey of contemporary multimedia encryption and watermarking techniques, which enable a secure exchange of multimedia intellectual property. Part I, Digital Rights Management (DRM) for Multimedia, introduces DRM concepts and models for multimedia content protection, and presents the key players. Part II, Multimedia Cryptography, provides an overview of modern cryptography, with the focus on modern image, video, speech, and audio encryption techniques. This book also provides an advanced concept of visual and audio sharing tec

  18. Teaching of Multimedia Presentation Creation

    OpenAIRE

    Ingrid Nagyová; Milan Turčáni

    2008-01-01

    Multimedia presentation has its well-founded place in classwork and in the teaching process itself. Multimedia enables teachers to speak to their pupils and students through pictures and sounds. Computer presentation accompanies the teacher in the teaching process that thus becomes more comprehensive, well-considered and effective. In addition classwork supported by multimedia activities is more interesting and attractive for students. There is no doubt that the competence and skill in creati...

  19. Multimedia programming with pure data

    CERN Document Server

    Chung, Bryan

    2013-01-01

    A quick and comprehensive tutorial book for media designers to jump-start interactive multimedia production with computer graphics, digital audio, digital video, and interactivity, using the Pure Data graphical programming environment.An introductory book on multimedia programming for media artists/designers who like to work on interactivity in their projects, digital art/design students who like to learn the first multimedia programming technique, and audio-visual performers who like to customize their performance sets

  20. Intelligent Interactive Multimedia

    CERN Document Server

    Watanabe, Toyohide; Takahashi, Naohisa; 5th International Conference on Intelligent Interactive Multimedia Systems and Services

    2012-01-01

    This volume contains the Proceedings of the 5th International Conference on Intelligent Interactive Multimedia Systems and Services (KES-IIMSS-12).  The Conference was jointly organised by Nagoya University in Japan and the KES International organisation, and held in the attractive city of Gifu.   The KES-IIMSS conference series, (series chairs Prof. Maria Virvou and Prof. George Tsihrintzis), presents novel research in various areas of intelligent multimedia system relevant to the development of a new generation of interactive, user-centric devices and systems.  The aim of the conference is to provide an internationally respected forum for scientific research in the technologies and applications of this new and dynamic research area.

  1. Flash Builder charting and multimedia

    CERN Document Server

    Rocchi, Cesare

    2010-01-01

    Charting and multimedia are two vital tools for data-driven applications. Learn about the main components of the chart library included in Flash Builder, and see how to build and customize widely used charts. Turning your attention to the multimedia capabilities of the Flex framework, you will review the multimedia components built into the Flex library, and learn how to use ActionScript to manipulate video and audio files. Charting and Multimedia is the third of five articles that will be compiled in the book, Data Visualization with Flash Builder: Designing RIA and AIR Applications with Rem

  2. Direct Broadcast Satellite: Radio Program

    Science.gov (United States)

    Hollansworth, James E.

    1992-01-01

    NASA is committed to providing technology development that leads to the introduction of new commercial applications for communications satellites. The Direct Broadcast Satellite-Radio (DBS-R) Program is a joint effort between The National Aeronautics and Space Administration (NASA) and The United States Information Agency/Voice of America (USIA/VOA) directed at this objective. The purpose of this program is to define the service and develop the technology for a direct-to-listener satellite sound broadcasting system. The DBS-R Program, as structured by NASA and VOA, is now a three-phase program designed to help the U.S. commercial communications satellite and receiver industry bring about this new communications service. Major efforts are being directed towards frequency planning hardware and service development, service demonstration, and experimentation with new satellite and receiver technology.

  3. Performance Evaluation and Parameter Optimization of SoftCast Wireless Video Broadcast

    Directory of Open Access Journals (Sweden)

    Dongxue Yang

    2015-08-01

    Full Text Available Wireless video broadcast plays an imp ortant role in multimedia communication with the emergence of mobile video applications. However, conventional video broadcast designs suffer from a cliff effect due to separated source and channel encoding. The newly prop osed SoftCast scheme employs a cross-layer design, whose reconstructed video quality is prop ortional to the channel condition. In this pap er, we provide the p erformance evaluation and the parameter optimization of the SoftCast system. Optimization principles on parameter selection are suggested to obtain a b etter video quality, o ccupy less bandwidth and/or utilize lower complexity. In addition, we compare SoftCast with H.264 in the LTE EPA scenario. The simulation results show that SoftCast provides a b etter p erformance in the scalability to channel conditions and the robustness to packet losses.

  4. Asymmetric Directional Multicast for Capillary Machine-to-Machine Using mmWave Communications.

    Science.gov (United States)

    Kwon, Jung-Hyok; Kim, Eui-Jik

    2016-01-01

    The huge demand for high data rate machine-to-machine (M2M) services has led to the use of millimeter Wave (mmWave) band communications with support for a multi-Gbps data rate through the use of directional antennas. However, unnecessary sector switching in multicast transmissions with directional antennas results in a long delay, and consequently a low throughput. We propose asymmetric directional multicast (ADM) for capillary M2M to address this problem in mmWave communications. ADM provides asymmetric sectorization that is optimized for the irregular deployment pattern of mulicast group members. In ADM, an M2M gateway builds up asymmetric sectors with a beamwidth of a different size to cover all multicast group members with the minimum number of directional transmissions. The performance of ADM under various simulation environments is evaluated through a comparison with legacy mmWave multicast. The results of the simulation indicate that ADM achieves a better performance in terms of the transmission sectors, the transmission time, and the aggregate throughput when compared with the legacy multicast method.

  5. Mobility Based Key Management Technique for Multicast Security in Mobile Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    B. Madhusudhanan

    2015-01-01

    Full Text Available In MANET multicasting, forward and backward secrecy result in increased packet drop rate owing to mobility. Frequent rekeying causes large message overhead which increases energy consumption and end-to-end delay. Particularly, the prevailing group key management techniques cause frequent mobility and disconnections. So there is a need to design a multicast key management technique to overcome these problems. In this paper, we propose the mobility based key management technique for multicast security in MANET. Initially, the nodes are categorized according to their stability index which is estimated based on the link availability and mobility. A multicast tree is constructed such that for every weak node, there is a strong parent node. A session key-based encryption technique is utilized to transmit a multicast data. The rekeying process is performed periodically by the initiator node. The rekeying interval is fixed depending on the node category so that this technique greatly minimizes the rekeying overhead. By simulation results, we show that our proposed approach reduces the packet drop rate and improves the data confidentiality.

  6. Optimizing on multiple constrained QoS multicast routing algorithms based on GA

    Institute of Scientific and Technical Information of China (English)

    孙宝林; 李腊元

    2004-01-01

    With the rapid development of Internet, mobile networks and high-performance networking technology,multiple constrained QoS multicast routing optimization in networks with uncertain parameters has become a very important research issue in the areas of networks and distributed systems. It is also a challenging and hard problem to the next generation Internet and high-performance networks, and has attracted the interests of many people. This paper discusses the multiple constrained QoS multicast routing problem, which may deal with the delay, delay jitter,bandwidth and packet loss metrics, and describes a network model for researching the routing problem. The paper mainly presents multiple constrained QoS multicast routing algorithm (MCQMRA), a QoS multicast routing policy for Internet,mobile network or other high-performance networks, which is based on the genetic algorithm (GA) and can provide QoS-sensitive paths in a scalable and flexible wayin the network environment with uncertain parameters. The MCQMRA can also optimize the network resources such as bandwidth, delay, packet loss metrics and can converge to the optimal or near-optimal solution within few iterations, even for the network environment with uncertain parameters. Simulation results show that MCQMRA is an available approach to QoS multicast routing decision.

  7. Mobility based key management technique for multicast security in mobile ad hoc networks.

    Science.gov (United States)

    Madhusudhanan, B; Chitra, S; Rajan, C

    2015-01-01

    In MANET multicasting, forward and backward secrecy result in increased packet drop rate owing to mobility. Frequent rekeying causes large message overhead which increases energy consumption and end-to-end delay. Particularly, the prevailing group key management techniques cause frequent mobility and disconnections. So there is a need to design a multicast key management technique to overcome these problems. In this paper, we propose the mobility based key management technique for multicast security in MANET. Initially, the nodes are categorized according to their stability index which is estimated based on the link availability and mobility. A multicast tree is constructed such that for every weak node, there is a strong parent node. A session key-based encryption technique is utilized to transmit a multicast data. The rekeying process is performed periodically by the initiator node. The rekeying interval is fixed depending on the node category so that this technique greatly minimizes the rekeying overhead. By simulation results, we show that our proposed approach reduces the packet drop rate and improves the data confidentiality.

  8. Self-Organized Hash Based Secure Multicast Routing Over Ad Hoc Networks

    Directory of Open Access Journals (Sweden)

    Amit Chopra

    2016-02-01

    Full Text Available Multicast group communication over mobile ad hoc networks has various challenges related to secure data transmission. In order to achieve this goal, there is a need to authenticate the group member as well as it is essential to protect the application data, routing information, and other network resources etc. Multicast-AODV (MAODV is the extension of an AODV protocol, and there are several issues related to each multicast network operation. In the case of dynamic group behavior, it becomes more challenging to protect the resources of a particular group. Researchers have developed different solutions to secure multicast group communication, and their proposed solutions can be used for resource protection at different layers i.e. application layer, physical layer, network layer, etc. Each security solution can guard against a particular security threat. This research paper introduced a self-organized hash based secure routing scheme for multicast ad hoc networks. It uses group Diffie-Hellman method for key distribution. Route authentication and integrity, both are ensured by generating local flag codes and global hash values. In the case of any violation, route log is monitored to identify the malicious activities.

  9. Enhanced first-in-first-out-based round-robin multicast scheduling algorithm for input-queued switches

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert

    2011-01-01

    This study focuses on the multicast scheduling for M × N input-queued switches. An enhanced first-in-first-out -based round-robin multicast scheduling algorithm is proposed with a function of searching deeper into queues to reduce the head-of-line (HOL) blocking problem and thereby the multicast...... out on the decision matrix to reduce the number of transmission for each cell. To reduce the HOL blocking problem, a complement matrix is constructed based on the traffic matrix and the decision matrix, and a process of searching deeper into the queues is carried out to find cells that can be sent...... to the idle outputs. Simulation results show that the proposed function of searching deeper into the queues can alleviate the HOL blocking and as a result reduce the multicast latency significantly. Under both balanced and unbalanced multicast traffic, the proposed algorithm is able to maintain a stable...

  10. REAL-TIME LICENSING MANAGEMENT OF SECURE MULTIMEDIA CONTENT DELIVERY

    Institute of Scientific and Technical Information of China (English)

    马兆丰; 冯博琴

    2004-01-01

    Media Commerce is now becoming a new trend which results from faster development of network bandwidth and high availability of multimedia technologies, how to protect media content from being used in a right-violated way is one of most important issues to take into account. In this paper, a novel and efficient authorization and authentication Digital Rights Management (DRM) schema is proposed firstly for secure multimedia delivery, then based on the schema, a real-time digital signature algorithm built on Elliptic Curve Cryptography (ECC) is adopted for fast authentication and verification of licensing management, thus secure multimedia delivery via TCP/RTP can efficiently work with real-time transaction response and high Quality of Service (QoS) . Performance evaluations manifest the proposed schema is secure, available for real-time media stream authentication and authorization without much effected of QoS. The proposed schema is not only available for Client/Server media service but can be easily extended to P2P and broadcasting network for trusted rights management.

  11. A rate based congestion control algorithm in networks with coexisting unicast and multicast sessions

    Institute of Scientific and Technical Information of China (English)

    Qian Dong; Jianying Xie

    2003-01-01

    The optimal rate control problem in networks with unicast and multirate multicast sessions is investigated. A penaltyfunction approach is used to solve a convex program formulation of this problem, and then a heuristic rate control algorithm is de-rived. The algorithm is distributed, and suitable both for source-driven unicast sessions and receiver-driven multicast sessions. Toobtain practical viability, the computational burden on core routers as well as end-hosts is kept very low, also is the overhead of net-work congestion feedback. Simulation results show that the algorithm guarantees TCP (Transmission Control Protocol)-based anicastsessions coexisting with multirate multicast sessions in a fair and friendly manner. It is also shown that various fairness criteria ofresource allocation could be achieved by choosing appropriate utility functions, and resource-utilizing efficiencies would be like wisedifferent.

  12. The specification-based validation of reliable multicast protocol: Problem Report. M.S. Thesis

    Science.gov (United States)

    Wu, Yunqing

    1995-01-01

    Reliable Multicast Protocol (RMP) is a communication protocol that provides an atomic, totally ordered, reliable multicast service on top of unreliable IP multicasting. In this report, we develop formal models for RMP using existing automated verification systems, and perform validation on the formal RMP specifications. The validation analysis help identifies some minor specification and design problems. We also use the formal models of RMP to generate a test suite for conformance testing of the implementation. Throughout the process of RMP development, we follow an iterative, interactive approach that emphasizes concurrent and parallel progress of implementation and verification processes. Through this approach, we incorporate formal techniques into our development process, promote a common understanding for the protocol, increase the reliability of our software, and maintain high fidelity between the specifications of RMP and its implementation.

  13. On-demand multicast routing protocol based on node classification in MANET

    Institute of Scientific and Technical Information of China (English)

    DENG Xia; SUN Li-min; WANG Jian-xin; LUO Yu-hong; CHEN Jian-er

    2006-01-01

    An improved on-demand multicast routing protocol(ODMRP), node classification on-demand multicast routing protocol(NC-ODMRP), which is based on node classification in mobile ad hoc networks was proposed. NCODMRP classifies nodes into such three categories as ordinary node, forwarding group(FG) node, neighbor node of FG node according to their history forwarding information. The categories are distinguished with different weights by a weight table in the nodes. NC-ODMRP chooses the node with the highest weight as an FG node during the setup of forwarding group, which reduces a lot of redundant FG nodes by sharing more FG nodes between different sender and receiver pairs. The simulation results show that NC-ODMRP can reduce more than 20% FG number of ODMRP, thus enhances nearly 14% data forwarding efficiency and 12% energy consumption efficiency when the number of multicast senders is more than 5.

  14. On the stability of multicast flow aggregation in IP over optical network for IPTV delivery

    Institute of Scientific and Technical Information of China (English)

    Xuan Luo; Yaohui Jin; Qingji Zeng; Weiqiang Sun; Wei Guo; Weisheng Hu

    2008-01-01

    The stable multicast flow aggregation (MFA) problem in internet protocol (IP) over optical network under the dynamical scenario is studied. Given an optical network topology, there is a set of head ends and access routers attached to the optical network, in which each head end can provide a set of programs (IP multicasting flows) and each access router requests a set of programs, we find a set of stable light-trees to accommodate the optimally aggregated multicast IP flows if the requests of access routers changed dynamically. We introduce a program correlation matrix to describe the preference of end users' requests. As the original MFA problem is NP-complete, a heuristic approach, named most correlated program first (MCPF), is presented and compared with the extended least tree first (ELTF) algorithm which is topologyaware. Simulation results show that MCPF can achieve better performance than ELTF in terms of stability with negligible increment of network resource usage.

  15. A Novel Video Data-Source Authentication Model Based on Digital Watermarking and MAC in Multicast

    Institute of Scientific and Technical Information of China (English)

    ZHAO Anjun; LU Xiangli; GUO Lei

    2006-01-01

    A novel video data authentication model based on digital video watermarking and MAC (message authentication code) in multicast protocol is proposed in this paper. The digital watermarking which composes of the MAC of the significant video content, the key and instant authentication data is embedded into the insignificant video component by the MLUT (modified look-up table) video watermarking technology. We explain a method that does not require storage of each data packet for a time, thus making receiver not vulnerable to DOS (denial of service) attack. So the video packets can be authenticated instantly without large volume buffer in the receivers. TESLA(timed efficient stream loss-tolerant authentication) does not explain how to select the suitable value for d, which is an important parameter in multicast source authentication. So we give a method to calculate the key disclosure delay (number of intervals). Simulation results show that the proposed algorithms improve the performance of data source authentication in multicast.

  16. A Grooming Nodes Optimal Allocation Method for Multicast in WDM Networks

    Directory of Open Access Journals (Sweden)

    Chengying Wei

    2016-01-01

    Full Text Available The grooming node has the capability of grooming multicast traffic with the small granularity into established light at high cost of complexity and node architecture. In the paper, a grooming nodes optimal allocation (GNOA method is proposed to optimize the allocation of the grooming nodes constraint by the blocking probability for multicast traffic in sparse WDM networks. In the proposed GNOA method, the location of each grooming node is determined by the SCLD strategy. The improved smallest cost largest degree (SCLD strategy is designed to select the nongrooming nodes in the proposed GNOA method. The simulation results show that the proposed GNOA method can reduce the required number of grooming nodes and decrease the cost of constructing a network to guarantee a certain request blocking probability when the wavelengths per fiber and transmitter/receiver ports per node are sufficient for the optical multicast in WDM networks.

  17. Impact of Rushing attack on Multicast in Mobile Ad Hoc Network

    CERN Document Server

    Palanisamy, V

    2009-01-01

    A mobile ad hoc network (MANETs) is a self-organizing system of mobile nodes that communicate with each other via wireless links with no fixed infrastructure or centralized administration such as base station or access points. Nodes in a MANETs operate both as host as well as routers to forward packets for each other in a multihop fashion. For many applications in wireless networks, multicasting is an important and frequent communication service. By multicasting, since a single message can be delivered to multiple receivers simultaneously. It greatly reduces the transmission cost when sending the same packet to multiple recipients. The security issue of MANETs in group communications is even more challenging because of involvement of multiple senders and multiple receivers. At that time of multicasting, mobile ad hoc network are unprotected by the attacks of malicious nodes because of vulnerabilities of routing protocols. Some of the attacks are Rushing attack, Blackhole attack, Sybil attack, Neighbor attack ...

  18. Reliability Evaluation Method for IP Multicast Communication under QoS Constraints

    Institute of Scientific and Technical Information of China (English)

    Dai Fusheng; Bao Xuecai; Han Weizhan

    2011-01-01

    In order to estimate the reliability performance of multicast communication under multiple constraint conditions,the weight of service rate and the reliability index are defined,accompanying the calculation method.Firstly,according to the Quality of Service requirements,the appropriate routings between the central node and target nodes that meet the requirements are calculated using the iterative method in the weighted internet.Then,the disjoint set of network state and the coefficients of weighted service rate are calculated by decomposition and merge methods.Lastly,the formula for calculating the service rate is obtained based on the disjoint set of network state and the calculation of the reliability index will be completed.The simulation result shows that the reliability of multicast communication can be appropriately reflected by the weight of service rate and the calculation method,which can provide the theoretical basis for the reliability evaluation of multicast communication.

  19. A TWO-LAYER RECURRENT NEURAL NETWORK BASED APPROACH FOR OVERLAY MULTICAST

    Institute of Scientific and Technical Information of China (English)

    Liu Shidong; Zhang Shunyi; Zhou Jinquan; Qiu Gong'an

    2008-01-01

    Overlay multicast has become one of the most promising multicast solutions for IP network, and Neutral Network(NN) has been a good candidate for searching optimal solutions to the constrained shortest routing path in virtue of its powerful capacity for parallel computation. Though traditional Hopfield NN can tackle the optimization problem, it is incapable of dealing with large scale networks due to the large number of neurons. In this paper, a neural network for overlay multicast tree computation is presented to reliably implement routing algorithm in real time. The neural network is constructed as a two-layer recurrent architecture, which is comprised of Independent Variable Neurons (IDVN) and Dependent Variable Neurons (DVN), according to the independence of the decision variables associated with the edges in directed graph. Compared with the heuristic routing algorithms, it is characterized as shorter computational time, fewer neurons, and better precision.

  20. Cognitive Synergy in Multimedia Learning

    Science.gov (United States)

    Kim, Daesang; Kim, Dong-Joong; Whang, Woo-Hyung

    2013-01-01

    The main focus of our study was to investigate multimedia effects that had different results from the findings of existing multimedia learning studies. First, we describe and summarize three experimental studies we conducted from 2006 to 2010. Then we analyze our findings to explore learner characteristics that may impact the cognitive processes…

  1. The Features of Multimedia Teaching

    Institute of Scientific and Technical Information of China (English)

    DuYaomei

    2004-01-01

    The first feature of a multimedia teaching system lies in that it has to incorporate into its own the synchronic teaching vs. the diachronic teaching in different time "zones". The priority of such multimedia approach is that the learner can arrange and control their own time and energy and the whole teaching schedule in close accordance with their own actual situations and interests.

  2. Multimedia Modules for Electromagnetics Education.

    Science.gov (United States)

    De Los Santos Vidal, Oriol; Iskander, Magdy F.

    1997-01-01

    Multimedia technology is an invaluable teaching and learning resource. One advantage of technology based education is the ability to combine practical applications, visualization of complex mathematical and abstract subjects, virtual labs, and guided use of simulation software. This article describes several multimedia tutorials for…

  3. Multimedia Principle in Teaching Lessons

    Science.gov (United States)

    Kari Jabbour, Khayrazad

    2012-01-01

    Multimedia learning principle occurs when we create mental representations from combining text and relevant graphics into lessons. This article discusses the learning advantages that result from adding multimedia learning principle into instructions; and how to select graphics that support learning. There is a balance that instructional designers…

  4. USING RADIO NEWS BROADCASTS AS LISTENING MATERIAL

    Institute of Scientific and Technical Information of China (English)

    1994-01-01

    INTRODUCTION As English teachers, we have devoted a lot of time to the teaching of listening comprehension using radio broadcasts. We began by using VOA news in special English with freshmen and a mixture of news in special English and standard news broadcasts with sophomores. Later BBC news was used. We accumulated a considerable amount of experience and did some research into the design of listening comprehension exercises. This article discusses how listening ability may be improved by using such broadcasts.

  5. A father protocol for quantum broadcast channels

    CERN Document Server

    Dupuis, F; Dupuis, Fr\\'ed\\'eric; Hayden, Patrick

    2006-01-01

    We present a new protocol for quantum broadcast channels based on the fully quantum Slepian-Wolf protocol. The protocol yields an achievable rate region for entanglement-assisted transmission of quantum information through a quantum broadcast channel that can be considered the quantum analogue of Marton's region for classical broadcast channels. The protocol can be adapted to yield achievable rate regions for unassisted quantum communication and for entanglement-assisted classical communication. Regularized versions of all three rate regions are provably optimal.

  6. 47 CFR 73.1250 - Broadcasting emergency information.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Broadcasting emergency information. 73.1250... RADIO BROADCAST SERVICES Rules Applicable to All Broadcast Stations § 73.1250 Broadcasting emergency information. (a) Emergency situations in which the broadcasting of information is considered as furthering...

  7. 37 CFR 381.2 - Definition of public broadcasting entity.

    Science.gov (United States)

    2010-07-01

    ... broadcasting entity. 381.2 Section 381.2 Patents, Trademarks, and Copyrights COPYRIGHT ROYALTY BOARD, LIBRARY... WITH NONCOMMERCIAL EDUCATIONAL BROADCASTING § 381.2 Definition of public broadcasting entity. As used in this part, the term public broadcasting entity means a noncommercial educational broadcast...

  8. 47 CFR 73.403 - Digital audio broadcasting service requirements.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Digital audio broadcasting service requirements. 73.403 Section 73.403 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES Digital Audio Broadcasting § 73.403 Digital audio broadcasting...

  9. 47 CFR 73.297 - FM stereophonic sound broadcasting.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false FM stereophonic sound broadcasting. 73.297... RADIO BROADCAST SERVICES FM Broadcast Stations § 73.297 FM stereophonic sound broadcasting. (a) An FM... broadcasting, equipment performance measurements must be made to ensure that the transmitted signal...

  10. Secrecy in Cooperative Relay Broadcast Channels

    CERN Document Server

    Ekrem, E

    2008-01-01

    We investigate the effects of user cooperation on the secrecy of broadcast channels by considering a cooperative relay broadcast channel. We show that user cooperation can increase the achievable secrecy region. We propose an achievable scheme that combines Marton's coding scheme for broadcast channels and Cover and El Gamal's compress-and-forward scheme for relay channels. We derive outer bounds for the rate-equivocation region using auxiliary random variables for single-letterization. Finally, we consider a Gaussian channel and show that both users can have positive secrecy rates, which is not possible for scalar Gaussian broadcast channels without cooperation.

  11. An Efficient Game Form for Multi-rate Multicast Service Provisioning

    CERN Document Server

    Kakhbod, Ali

    2011-01-01

    We consider the decentralized bandwidth/rate allocation problem in multi-rate multicast service provisioning with strategic users. We demonstrate that such a situation is the combination of a market problem and a public good problem. We present a mechanism/game form which possesses the following properties when the users' utilities are concave: (1) It implements in Nash equilibria the solution of the corresponding centralized rate allocation problem in multi-rate multicast service provisioning. (2) It is individually rational. (3) It is budget-balanced at all Nash equilibria of the game induced by the mechanism/game form as well as off equilibrium.

  12. Linear and non-linear video and TV applications using IPv6 and IPv6 multicast

    CERN Document Server

    Minoli, Daniel

    2012-01-01

    Provides options for implementing IPv6 and IPv6 multicast in service provider networks New technologies, viewing paradigms, and content distribution approaches are taking the TV/video services industry by storm. Linear and Nonlinear Video and TV Applications: Using IPv6 and IPv6 Multicast identifies five emerging trends in next-generation delivery of entertainment-quality video. These trends are observable and can be capitalized upon by progressive service providers, telcos, cable operators, and ISPs. This comprehensive guide explores these evolving directions in the TV/v

  13. Multi-Level Round-Robin Multicast Scheduling with Look-Ahead Mechanism

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert

    2011-01-01

    In this paper, we propose a multi-level round-robin multicast scheduling (MLRRMS) algorithm with look-ahead (LA) mechanism for N×N input-queued switches. Fan-out splitting is applied, where a multicast cell can be transferred to all its destinations over any number of cell times. The scheduler...... constructs the Traffic Matrix before each cell transmission based on the fan-out vectors of the cells in the queues. A scheduling pointer independently moves on each column of the Traffic Matrix in a round-robin fashion and returns the decision to the Decision Matrix. The sync procedure is carried out...

  14. Improved Multicast Traffic Scheduling Scheme in the Packet-Switching Systems

    Institute of Scientific and Technical Information of China (English)

    SONG Mei-na; SONG Jun-de; LI Hong-wen

    2004-01-01

    This paper proposes a new switching scheme of switch fabric, which is named Multicast-enabled Protocol Agnostic Forwarding Engine (M-PAFE). M-PAFE is a central scheduling crossbar-based switch fabric with embedded Combined Input and Output Queue from the queuing view. An extra switching path is dedicated for multicast cell processing in M-PAFE. And the simulation results are provided to evaluate the performance of M-PAFE in comparison with ESLIP, which is a well-known algorithm implemented in Cisco 12000 routers.

  15. 关于数字广播技术的特点及其应用探讨%Characteristics and its Application on Digital Broadcasting Technology

    Institute of Scientific and Technical Information of China (English)

    王勇

    2014-01-01

    随着社会经济的发展进步与科学技术的迅猛发展,许多技术都得到了一定程度的快速发展,尤其是广播技术更是发生了巨大变化,导致出现了数字广播技术,深受广播电视行业的普遍欢迎。该文对数字音频广播、数字多媒体广播、数字调幅广播、数字卫星声音广播、网上(数字)广播等几种数字广播技术及其特点进行了详细介绍,并进一步阐释了数字广播技术的应用前景,以期能够进一步扩展数字广播技术的应用范围。%With the rapid development of science and technology and social economy, many technology has been rapid develop-ment to a certain extent, especially radio technology is produced tremendous change, leading to the emergence of digital broad-casting technology, widely welcomed by the radio and TV industry. In this paper, the digital audio broadcasting, digital multime-dia broadcasting, digital AM broadcasting, digital satellite sound broadcasting, Internet (digital) broadcast several digital broadcast-ing technology and its characteristics are introduced in detail, and further illustrates the application prospect of digital broadcasting technology, in order to further expand the scope of application of the digital broadcasting technology.

  16. Automatization of Student Assessment Using Multimedia Technology.

    Science.gov (United States)

    Taniar, David; Rahayu, Wenny

    Most use of multimedia technology in teaching and learning to date has emphasized the teaching aspect only. An application of multimedia in examinations has been neglected. This paper addresses how multimedia technology can be applied to the automatization of assessment, by proposing a prototype of a multimedia question bank, which is able to…

  17. 14 CFR 1213.108 - Multimedia materials.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 5 2010-01-01 2010-01-01 false Multimedia materials. 1213.108 Section 1213... AND INFORMATION MEDIA § 1213.108 Multimedia materials. (a) NASA's multimedia material, from all... original or duplicate files of news-oriented imagery and other digital multimedia material generated...

  18. Multicast in Femtocell Networks: A Successive Interference Cancellation Approach

    Directory of Open Access Journals (Sweden)

    Donglin Hu

    2014-09-01

    Full Text Available A femtocell is a small cellular base station (BS, typically used for serving approved users within a small coverage. In this paper, we investigate the problem of data multicast in femtocell networks that incorporates superposition coding (SC and successive interference cancellation (SIC. The problem is to decide the transmission schedule for each BS, as well as the power allocation for the SC layers, to achieve a sufficiently large SNR for each layer to be decodable with SIC at each user. Minimizing the total BS power consumption achieves the goal of “green” communications. We formulate a Mixed Integer Nonlinear Programming (MINLP problem, and then reformulate the problem into a simpler form. Upper and lower performance bounds on the total BS power consumption are derived. Finally, we consider three typical connection scenarios, and develop optimal and nearoptimal algorithms for the three scenarios. The proposed algorithms have low computational complexity, and outperform a heuristic scheme with considerable gains in our simulation study.

  19. Opportunistic Relay Selection in Multicast Relay Networks using Compressive Sensing

    KAUST Repository

    Elkhalil, Khalil

    2014-12-01

    Relay selection is a simple technique that achieves spatial diversity in cooperative relay networks. However, for relay selection algorithms to make a selection decision, channel state information (CSI) from all cooperating relays is usually required at a central node. This requirement poses two important challenges. Firstly, CSI acquisition generates a great deal of feedback overhead (air-time) that could result in significant transmission delays. Secondly, the fed back channel information is usually corrupted by additive noise. This could lead to transmission outages if the central node selects the set of cooperating relays based on inaccurate feedback information. In this paper, we introduce a limited feedback relay selection algorithm for a multicast relay network. The proposed algorithm exploits the theory of compressive sensing to first obtain the identity of the “strong” relays with limited feedback. Following that, the CSI of the selected relays is estimated using linear minimum mean square error estimation. To minimize the effect of noise on the fed back CSI, we introduce a back-off strategy that optimally backs-off on the noisy estimated CSI. For a fixed group size, we provide closed form expressions for the scaling law of the maximum equivalent SNR for both Decode and Forward (DF) and Amplify and Forward (AF) cases. Numerical results show that the proposed algorithm drastically reduces the feedback air-time and achieves a rate close to that obtained by selection algorithms with dedicated error-free feedback channels.

  20. 76 FR 55817 - Broadcast Applications and Proceedings; Fairness Doctrine and Digital Broadcast Television...

    Science.gov (United States)

    2011-09-09

    ... COMMISSION 47 CFR Parts 1, 73 and 76 Broadcast Applications and Proceedings; Fairness Doctrine and Digital Broadcast Television Redistribution Control; Fairness Doctrine, Personal Attacks, Political Editorials and... legal effect and are obsolete. The deleted rules include ] the fairness doctrine, broadcast flag rules...

  1. Broadcasting: Does It Belong in the Department of Speech? Traditional Concepts in Speech and Broadcasting.

    Science.gov (United States)

    Greene, Robert J.

    Educational institutions were among the pioneers in the development of radio broadcasting. By 1938, over 300 colleges reported offering at least one course in radio. In more recent times the surveys compiled by Harold Niven for the "Journal of Broadcasting" show a continued interest in broadcasting courses. The trend is toward Communications or…

  2. 47 CFR 73.1692 - Broadcast station construction near or installation on an AM broadcast tower.

    Science.gov (United States)

    2010-10-01

    ... AM station to return to the direct method of power determination. (d) Tower erections or... installation on an AM broadcast tower. 73.1692 Section 73.1692 Telecommunication FEDERAL COMMUNICATIONS... Stations § 73.1692 Broadcast station construction near or installation on an AM broadcast tower. Where...

  3. Cable Television and Satellite Broadcasting

    Science.gov (United States)

    Blackburn, J. F.

    1990-05-01

    Sponsored by the Financial Times, this 2-day conference was the eighth in the annual series. This particular conference marks the end of the first year of the Sky Television network's operation in the U.K. The conference was held just before British Satellite Broadcasting (BSB) goes into operation. With speakers from the U.K., the U.S., France, Japan, and the Netherlands, attendance exceeded all previous conferences. The 400 participants came mainly from the U.K., but also represented were France, the Netherlands, U.S., Australia, Spain, Norway, Canada, Switzerland, Denmark, Federal Republic of Germany (FRG), Finland, Monaco, Belgium, South Africa, Italy, Luxembourg, Irish Republic, and Malta.

  4. Watershed Education for Broadcast Meteorologists

    Science.gov (United States)

    Lamos, J. P.; Sliter, D.; Espinoza, S.; Spangler, T. C.

    2006-12-01

    The National Environmental Education and Training Organization (NEETF) published a report in 2005 that summarized the findings of ten years of NEETF and Roper Research. The report stated, "Our years of data from Roper surveys show a persistent pattern of environmental ignorance even among the most educated and influential members of society." Market research has also shown that 80% of television viewers list the weather as the primary reason for watching the local news. Broadcast meteorologists, with a broader understanding of environmental and related sciences have an opportunity to use their weathercasts to inform the public about the environment and the factors that influence environmental health. As "station scientists," broadcast meteorologists can use the weather, and people's connection to it, to broaden their understanding of the environment they live in. Weather and watershed conditions associated with flooding and drought have major human and environmental impacts. Increasing the awareness of the general public about basic aspects of the hydrologic landscape can be an important part of mitigating the adverse effects of too much or too little precipitation, and of protecting the environment as well. The concept of a watershed as a person's natural neighborhood is a very important one for understanding hydrologic and environmental issues. Everyone lives in a watershed, and the health of a watershed is the result of the interplay between weather and human activity. This paper describes an online course to give broadcast meteorologists a basic understanding of watersheds and how watersheds are impacted by weather. It discusses how to convey watershed science to a media- savvy audience as well as how to model the communication of watershed and hydrologic concepts to the public. The course uses a narrative, story-like style to present its content. It is organized into six short units of instruction, each approximately 20 minutes in duration. Each unit is

  5. Surgical education through video broadcasting.

    Science.gov (United States)

    Nagengast, Eric S; Ramos, Margarita S; Sarma, Hiteswar; Deshpande, Gaurav; Hatcher, Kristin; Magee, William P; Campbell, Alex

    2014-09-01

    Surgical training is facing new obstacles. As advancements in medicine are made, surgeons are expected to know more and to be able to perform more procedures. In the western world, increasing restrictions on residency work hours are adding a new hurdle to surgical training. In low-resource settings, a low attending-to-resident ratio results in limited operative experience for residents. Advances in telemedicine may offer new methods for surgical training. In this article, the authors share their unique experience using live video broadcasting of surgery for educational purposes at a comprehensive cleft care center in Guwahati, India.

  6. Multimedia and ubiquitous engineering MUE 2013

    CERN Document Server

    Ng, Joseph; Jeong, Hwa; Waluyo, Borgy

    2013-01-01

    The new multimedia standards (for example, MPEG-21) facilitate the seamless integration of multiple modalities into interoperable multimedia frameworks, transforming the way people work and interact with multimedia data. These key technologies and multimedia solutions interact and collaborate with each other in increasingly effective ways, contributing to the multimedia revolution and having a significant impact across a wide spectrum of consumer, business, healthcare, education, and governmental domains. Multimedia and Ubiquitous Engineering provides an opportunity for academic and industry professionals to discuss recent progress in the area of multimedia and ubiquitous environment including models and systems, new directions, novel applications associated with the utilization and acceptance of ubiquitous computing devices and systems.

  7. Multimedia Information Networks in Social Media

    Science.gov (United States)

    Cao, Liangliang; Qi, Guojun; Tsai, Shen-Fu; Tsai, Min-Hsuan; Pozo, Andrey Del; Huang, Thomas S.; Zhang, Xuemei; Lim, Suk Hwan

    The popularity of personal digital cameras and online photo/video sharing community has lead to an explosion of multimedia information. Unlike traditional multimedia data, many new multimedia datasets are organized in a structural way, incorporating rich information such as semantic ontology, social interaction, community media, geographical maps, in addition to the multimedia contents by themselves. Studies of such structured multimedia data have resulted in a new research area, which is referred to as Multimedia Information Networks. Multimedia information networks are closely related to social networks, but especially focus on understanding the topics and semantics of the multimedia files in the context of network structure. This chapter reviews different categories of recent systems related to multimedia information networks, summarizes the popular inference methods used in recent works, and discusses the applications related to multimedia information networks. We also discuss a wide range of topics including public datasets, related industrial systems, and potential future research directions in this field.

  8. PIM-SM Based Multicast Security%基于PIM-SM协议IP组播安全技术

    Institute of Scientific and Technical Information of China (English)

    黄舒; 董喜明; 郭云峰

    2014-01-01

    With the rapid development of the network technology, more bandwidth is required. Multicast transmission offers efficient network resource consumption. Multicast security is a hot issue. Multicast security problem hinders the development of multicast technology. This paper discusses the principles of multicast protocol PIM-SM and makes a detailed description of a method to prevent vicious multicast source attacking. The method can improve the reliability of multicast system.%伴随着互联网的高速发展, Internet 上涌现了许多需要高带宽支持的应用。组播技术能有效的利用网络带宽资源。组播的安全性一直是一个热点问题,也是阻碍组播发展的一个主要问题。本文针对虚假组播源产生垃圾消息恶性攻击提出了一个基于 PIM-SM 组播协议的预防方案,实验结果表明,该方案能提高组播系统的可靠性。

  9. History of Satellite TV Broadcasting and Satellite Broadcasting Market in Turkey

    Directory of Open Access Journals (Sweden)

    Mihalis KUYUCU

    2015-09-01

    Full Text Available The present study analyses the satellite broadcasting that is the first important development that emerged as a result of digitalization in communication technologies and its reflections in Turkey. As the first milestone in the globalization of television broadcasting, satellite broadcasting provided substantial contribution towards the development of the media. Satellite bro adcasting both increased the broadcasting quality and geographical coverage of the television media. A conceptual study was carried out in the first part of the study in connection with the history of satellite broadcasting in Turkey and across the world. In the research part of the study, an analysis was performed on 160 television channels that broadcast in Turkey via Turksat Satellite. Economic structure of the television channels broadcasting in Turkey via satellite was studied and an analysis was perfo rmed on the operational structure of the channels. As a result of the study, it was emphasized that the television channels broadcasting via satellite platform also use other platforms for the purpose of spreading their broadcasts and television channel ow ners make investments in different branches of the media, too. Capital owners invest in different business areas other than the media although television channels broadcasting via Turksat mostly focus on thematic broadcasting and make effort to generate ec onomic income from advertisements. Delays are encountered in the course of the convergence between the new media and television channels that broadcast only from the satellite platform and such television channels experience more economic problems than the other channels. New media and many TV broadcasting platforms emerged as a result of the developments in the communication technologies. In television broadcasting, satellite platform is not an effective platform on its own. Channels make effort to reach t o more people by using other platforms in addition to

  10. Equilibrium in a random viewer model of television broadcasting

    DEFF Research Database (Denmark)

    Hansen, Bodil Olai; Keiding, Hans

    2014-01-01

    The authors considered a model of commercial television market with advertising with probabilistic viewer choice of channel, where private broadcasters may coexist with a public television broadcaster. The broadcasters influence the probability of getting viewer attention through the amount...

  11. 78 FR 42700 - Radio Broadcasting Services; Matagorda, Texas

    Science.gov (United States)

    2013-07-17

    ... COMMISSION 47 CFR Part 73 Radio Broadcasting Services; Matagorda, Texas AGENCY: Federal Communications Commission. ACTION: Final rule. SUMMARY: The Audio Division, at the request of Tejas Broadcasting Ltd., LLP... broadcasting. Federal Communications Commission. Nazifa Sawez, Assistant Chief, Audio Division, Media...

  12. 76 FR 76337 - Television Broadcasting Services; Lincoln, NE

    Science.gov (United States)

    2011-12-07

    ... COMMISSION 47 CFR Part 73 Television Broadcasting Services; Lincoln, NE AGENCY: Federal Communications... Lincoln Broadcasting, LLC (``LBL''), the licensee of KFXL-TV, channel 51, Lincoln, Nebraska, requesting... 73 Television, Television broadcasting. Federal Communications Commission Barbara A. Kreisman,...

  13. Multimedia and Decision-Making Process

    Directory of Open Access Journals (Sweden)

    Ovidiu-Alin DOBRICAN

    2009-01-01

    Full Text Available Multimedia technology has changed the way we use computers. Multimedia transforms com-puters into a second person. Multimedia technology has made it possible for us to see, hear, read, feel, and talk to computers. Multimedia technology has transformed our use and understanding of computers. On the other hand, multimedia presentation is one of the fastest-growing sectors of the computer industry. Applications have appeared in many areas, such as training, education, business presentation, merchandising, and communications.

  14. Live broadcast from the Globe

    CERN Multimedia

    La tête au carréTuesday, 17 June 2008 between 2.00 and 3.00 p.m.“La tête au carré”, a France Inter radio programme devoted to science, will set up its sound booth at CERN for a special broadcast on the LHC.The journalist Mathieu Vidard will interview the following guests: - Pierre Van Hove, an experimental physicist working on CMS. He is a CNRS research scientist from the Institut Hubert Curien in Strasbourg, France.- Abdelhak Djouadi is a theoretical physicist. He is a research director at the CNRS’s Laboratoire de physique théorique at Orsay, France and holder of the CNRS silver medal.- Magali Gruwe, one of the engineers in charge of LHC operations at CERN.» To take part in this live broadcast, which is open to the public, come to the Globe at 1:30 p.m. The number of places is limited.» No specialist knowledge required.» See the programme's homepage

  15. 主动结点启动的可靠多播通信%Active-Node-Initiated Reliable Multicast

    Institute of Scientific and Technical Information of China (English)

    蔡洪斌; 周明天; 杨国纬

    2000-01-01

    Sender-initiated and receiver-initiated reliable multicast protocols can suffer performance degradation as increasing the number of receivers. New technology and new service of active network would resolve the problem of the scalable and reliable multicast. The paper presents an Active-Node-Initiated Reliable Multicast (ANIRM)protocol. The protocol, which guarantees the data packet to transport correctly form active node to active node,shifts the burden of providing reliable data transfer to active nodes and receivers. Theoretical analysis shows that ANIRM proposed here is,comparing with the traditional network protocol,better for bandwidth and data recovery delay.

  16. Algoritmos genéticos multiobjetivos aplicados ao roteamento multicast com qualidade de serviço

    OpenAIRE

    Vita, Stéfano Schwenck Borges Vale

    2009-01-01

    Roteamento multicast é uma maneira eficaz de se comunicar entre múltiplos roteadores em redes de computadores. Geralmente, a Qualidade de Serviço (QoS) é exigida como garantia na maior parte das aplicações multicast. Vários pesquisadores têm investigado a aplicação dos Algoritmos Genéticos em roteamento multicast com restrições QoS. Os ambientes evolutivos de roteamento que são propostos neste trabalho empregam uma abordagem multiobjetivos adotando o conceito de Ótimo de Pareto...

  17. Integrated all-optical wavelength multicasting for 40 Gbit/s PDM-QPSK signals using a single silicon waveguide

    Science.gov (United States)

    Feng, Xianglian; Wu, Zhihang; Wang, Xiaoyan; Gao, Shiming

    2017-09-01

    All-optical wavelength multicasting is presented and experimentally demonstrated for 40 Gbit/s polarization-division-multiplexed (PDM) nonreturn-to-zero quadrature phase-shift keying (QPSK) signals using four-wave mixing (FWM) with angled-polarization pumps in a silicon waveguide. Five multicast channels are obtained on the generated idlers. The eye diagrams, constellation diagrams, and bit error rates (BERs) of the QPSK sequences on the two polarization states are measured for each wavelength channel. The power penalties of all these multicast QPSK sequences on x or y polarization state are less than 2.0 dB at the BER of 3 × 10-3.

  18. Out-of-Sequence Preventative Cell Dispatching for Multicast Input-Queued Space-Memory-Memory Clos-Network

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert

    2011-01-01

    This paper proposes two out-of-sequence (OOS) preventative cell dispatching algorithms for the multicast input-queued space-memory-memory (IQ-SMM) Clos-network switch architecture, i.e. the multicast flow-based DSRR (MF-DSRR) and the multicast flow-based round-robin (MFRR). Treating each cell...... independently, the desynchronized static round-robin (DSRR) cell dispatching scheme can evenly distribute cells to the central switching modules, however, its frequent change of the input switching module connection pattern causes a serious OOS problem to the IQ-SMM architecture. Therefore large reassembly...

  19. Television broadcast from space systems: Technology, costs

    Science.gov (United States)

    Cuccia, C. L.

    1981-01-01

    Broadcast satellite systems are described. The technologies which are unique to both high power broadcast satellites and small TV receive-only earth terminals are also described. A cost assessment of both space and earth segments is included and appendices present both a computer model for satellite cost and the pertinent reported experience with the Japanese BSE.

  20. The Production and Teaching of Broadcast News.

    Science.gov (United States)

    Wiley, Gale F.

    1987-01-01

    Presents description of local-area network of personal computers installed in the Broadcast News Laboratory at the University of Texas at Austin to help produce and teach broadcast news. Highlights include development and design of the system, software and hardware considerations, and the use of tutorials for writing and technical concepts. (LRW)

  1. Statistical Trends in Broadcasting. Ninth Edition.

    Science.gov (United States)

    Blair (John) and Co., New York, NY.

    A review of trends in broadcasting and an overall economic profile of the broadcasting industry for 1972, with projections for 1973, are given by a collection of tables and graphs. The first portion presents data on total advertising expenditures and trends, along with information on the gross national product and personal consumption spending.…

  2. Language Choice in Transnational Radio Broadcasting.

    Science.gov (United States)

    Wood, Richard E.

    1979-01-01

    Discusses the comparative strength of language use as measured by languages used in transnational radio broadcasting. Findings indicate that politics and Christian evangelism are the two major concerns dominating broadcasting and that language selection policy influences political, social, and cultural change. (JMF)

  3. Management Theories and Broadcasting: A Handbook.

    Science.gov (United States)

    Craig, J. Robert; Hindmarsh, Wayne A.

    Today's contemporary management and motivation theories, as applied to the business of broadcasting, are the focus of the first section of this paper. It deals with the kinds and reactions of employees in broadcasting stations in relation to 11 motivational theories: (1) Theories X and Y, (2) Immaturity-Maturity Theory, (3) V Theory, (4) Z Theory,…

  4. The Quasi Nongovernmental Organization in Public Broadcasting

    Science.gov (United States)

    Grossman, Michael B.

    1969-01-01

    "Educational broadcasting faces a problem of remaining autonomous under increased governmental support through the Corporation for Public Broadcasting. Dr. Grossman draws parallels between what is happening in ETV and the history of autonomy and constituency in the schools and universities. (Editor)

  5. 47 CFR 73.1217 - Broadcast hoaxes.

    Science.gov (United States)

    2010-10-01

    ... broadcast station shall broadcast false information concerning a crime or a catastrophe if: (a) The licensee... harm would occur. A “crime” is any act or omission that makes the offender subject to criminal punishment by law. A “catastrophe” is a disaster or imminent disaster involving violent or sudden...

  6. High-Performance Broadcasting Algorithms on Cluster

    Institute of Scientific and Technical Information of China (English)

    舒继武; 魏英霞; 王鼎兴

    2004-01-01

    In many clusters connected by high-speed communication networks, the exact structure of the underlying communication network and the latency difference between different sending and receiving pairs may be ignored when they broadcast, such as in the approach adopted by the broadcasting method in MPICH,a widely used MPI implementation. However, the underlying network cluster topologies are becoming more and more complicated and the performance of traditional broadcasting algorithms, such as MPICH's MPI_Bcast, is far from good. This paper analyzed the impact of communication latencies and the underlying topologies on the performance of broadcasting algorithms for multilevel clusters. A multilevel model was developed for broadcasting in clusters with complicated topologies, which divides the cluster topology into many levels based on the underlying topology. The multilevel model was used to develop a new broadcast algorithm,MLM broadcast-2 (MLMB-2), that adapts to a wide range of clusters. Comparison of the performance of the counterpart MPI operation MPI_Bcast and MLMB-2 shows that MLMB-2 outperforms MPl_Bcast by decreasing the broadcast running time by 60%-90%.

  7. Moodle 2.5 multimedia

    CERN Document Server

    Fernandes, João

    2013-01-01

    A tutorial-based guide where readers can work through practical examples that clearly describe how to create multimedia applications using Moodle and integrate existing multimedia resources into Moodle courses.If you are a teacher or trainer who runs online courses and has a basic understanding of Moodle, this book will be ideal for you. It is not necessary to have an advanced technical background to create multimedia elements as the tasks will be simple, not time consuming, and will be practical for everyday use.

  8. Multimedia ontology representation and applications

    CERN Document Server

    Chaudhury, Santanu; Ghosh, Hiranmay

    2015-01-01

    The result of more than 15 years of collective research, Multimedia Ontology: Representation and Applications provides a theoretical foundation for understanding the nature of media data and the principles involved in its interpretation. The book presents a unified approach to recent advances in multimedia and explains how a multimedia ontology can fill the semantic gap between concepts and the media world. It relays real-life examples of implementations in different domains to illustrate how this gap can be filled.The book contains information that helps with building semantic, content-based

  9. Innovative multimedia for teaching nematology.

    Science.gov (United States)

    Eisenback, J D

    1993-09-01

    The availability of interactive multimedia authoring software programs promises to revolutionize the teaching of nematology. These programs integrate text, hypertext, graphics, animations, video, and sound. The user interacts with the information on demand in a nonlinear fashion. Beginning students can limit themselves to the general outlines of the subject, and advanced students can explore the information to the limits of their ability. Use of interactive multimedia does not eliminate the need for effective, enthusiastic teachers but provides a mechanism for the efficient transfer of information. An interactive multimedia presentation that supplements lectures in an introductory course is presented as an example of the application of this technology for teaching nematology.

  10. Metadata for the description of broadcast assets

    DEFF Research Database (Denmark)

    Efthimiadis, Efthimis N.; Mai, Jens Erik; Burrows, Paul E.

    2003-01-01

    The Corporation for Public Broadcasting (CPB) and public broadcasters consider Media Asset Management (MAM) of critical importance since without a concerted and cooperative plan to manage their vast library of content, broadcasters are unable to reach their potential for service in the digital age....... The concerns for Media Asset Management, human and technical, are myriad. Media Asset Management is the framework upon which many of the largest technology projects will be built, including the future interconnection system between and among CPB member stations. It is CPB's hope that its licensees...... and their partners in university, museum, and library communities, will work together to contribute to Media Asset Management solutions. These issues are not unique to Public Broadcasters. Similar issues are faced by all networks at different levels of complexity. This panel will present efforts by broadcasters...

  11. Safety message broadcast in vehicular networks

    CERN Document Server

    Bi, Yuanguo; Zhuang, Weihua; Zhao, Hai

    2017-01-01

    This book presents the current research on safety message dissemination in vehicular networks, covering medium access control and relay selection for multi-hop safety message broadcast. Along with an overall overview of the architecture, characteristics, and applications of vehicular networks, the authors discuss the challenging issues in the research on performance improvement for safety applications, and provide a comprehensive review of the research literature. A cross layer broadcast protocol is included to support efficient safety message broadcast by jointly considering geographical location, physical-layer channel condition, and moving velocity of vehicles in the highway scenario. To further support multi-hop safety message broadcast in a complex road layout, the authors propose an urban multi-hop broadcast protocol that utilizes a novel forwarding node selection scheme. Additionally, a busy tone based medium access control scheme is designed to provide strict priority to safety applications in vehicle...

  12. Broadcast Network Coverage with Multicell Cooperation

    Directory of Open Access Journals (Sweden)

    Hongxiang Li

    2010-01-01

    Full Text Available Multicell cooperation has been identified as one of the underlying principles for future wireless communication systems. This paper studies the benefits of multicell cooperation in broadcast TV network from an information theoretical perspective. We define outage capacity as the figure of merit and derive the broadcast coverage area to evaluate such system. Specifically, we calculate the broadcast coverage area with given common information rate and outage probabilities when multiple base stations collaboratively transmit the broadcast signals. For the general MIMO case where receivers have multiple antennas, we provide simulation results to illustrate the expanded coverage area. In all cases, our results show that the coverage of a TV broadcast network can be significantly improved by multicell cooperation.

  13. Independence between Korean Government and Broadcasting Industry

    Directory of Open Access Journals (Sweden)

    Yi-Chih Huang

    2015-01-01

    Full Text Available The recent success of Hallyu (Korean Wave first driven by the spread of TV dramas received academic attention for its effective national policies. However, little is known about how national policy is implemented and local industry capacity is maintained even after market opening. Therefore, the aim of this paper attempts to explore how and why state governs broadcasting industry effectively. Historical institutionalism has been used to explain the way that Korean governments had taken to collaborate with the broadcasting industry. The relation between governments and broadcasting industry, the changes of broadcasting policies and authorities responsible for regulating TV industry are involved. Results of this study showed that strong state intervention in Korea did lead to oligopoly, and the governments dominated the industry by designing the market structure. To conclude, this study may be of importance in explaining the governed independence between Korean governments and broadcasting industry, as well as how it contributed to the stable productivity and export competitiveness.

  14. Random broadcast on random geometric graphs

    Energy Technology Data Exchange (ETDEWEB)

    Bradonjic, Milan [Los Alamos National Laboratory; Elsasser, Robert [UNIV OF PADERBORN; Friedrich, Tobias [ICSI/BERKELEY; Sauerwald, Tomas [ICSI/BERKELEY

    2009-01-01

    In this work, we consider the random broadcast time on random geometric graphs (RGGs). The classic random broadcast model, also known as push algorithm, is defined as: starting with one informed node, in each succeeding round every informed node chooses one of its neighbors uniformly at random and informs it. We consider the random broadcast time on RGGs, when with high probability: (i) RGG is connected, (ii) when there exists the giant component in RGG. We show that the random broadcast time is bounded by {Omicron}({radical} n + diam(component)), where diam(component) is a diameter of the entire graph, or the giant component, for the regimes (i), or (ii), respectively. In other words, for both regimes, we derive the broadcast time to be {Theta}(diam(G)), which is asymptotically optimal.

  15. 基于CATV网的可靠多播机制研究%Research on Mechanism of Reliable Multicasting Based on CATV Network

    Institute of Scientific and Technical Information of China (English)

    朱梅; 李章维

    2011-01-01

    针对CATV网的带宽优势,提出了一种面向CATV网的IP多播流分发服务机制,客户端通过DVB卡分层接收流武文件,并利用IP网作为回传链路.该方案解决了单向广播网无法回传丢包及网络服务情况的问题,对于网络的突发性长时间丢包具有一定的稳健性.仿真结果显示该方案可靠性强,扩展性好,特别适合具有较多接收者的视频流分发.%According to the advantages of the broad bandwidth of CATV network, an IP multicast streaming distribution mechanism based on CATV network is proposed. Clients receive the streaming file with layer by DVB network interface, and intemet is used as the tatum channel to cope with the Probability of Packet Loss (PPL) and QoS in unidirectional broadcasting networks. The robustness is appeared when the packet loss of network bursts for a long time. The simulating results show that the scheme is reliable and expandable, and is particularly suitable for the video stream distribution with several receivers.

  16. Quick Recovery from Link Failures using Enhanced On-demand Multicast Routing Protocol

    Directory of Open Access Journals (Sweden)

    S. Muthumari Lakshmi

    2015-03-01

    Full Text Available The aim of this study is to reduce the number of link failures and provide a quick recovery mechanism in MANETs. Multicasting is one of the greatest issues among MANETs due to the seamless variations in topology and link dynamics. Due to the wireless nature of the network, the nodes are under the compulsion to perform communication at adverse situations for any emergency or defense operations. The On Demand Multicast Routing Protocol (ODMRP is one of the solutions proposed to avoid the multicasting problem in Wireless Mobile Ad hoc Network. In order to avoid excessive flooding of control messages in the network, Enhanced ODMRP was proposed that introduced short time frames to wait until the refresh messages are flooded. In this study, we propose a quick recovery mechanism that along with the EODMRP helps in the quick recovery from route failures and increases performance in the network. An analysis of the EODMRP protocol for multicasting in MANETs is presented along with the proposed quick recovery mechanism using simulations in the network simulator.

  17. A hybrid ACO/PSO based algorithm for QoS multicast routing problem

    Directory of Open Access Journals (Sweden)

    Manoj Kumar Patel

    2014-03-01

    Full Text Available Many Internet multicast applications such as videoconferencing, distance education, and online simulation require to send information from a source to some selected destinations. These applications have stringent Quality-of-Service (QoS requirements that include delay, loss rate, bandwidth, and delay jitter. This leads to the problem of routing multicast traffic satisfying QoS requirements. The above mentioned problem is known as the QoS constrained multicast routing problem and is NP Complete. In this paper, we present a swarming agent based intelligent algorithm using a hybrid Ant Colony Optimization (ACO/Particle Swarm Optimization (PSO technique to optimize the multicast tree. The algorithm starts with generating a large amount of mobile agents in the search space. The ACO algorithm guides the agents’ movement by pheromones in the shared environment locally, and the global maximum of the attribute values are obtained through the random interaction between the agents using PSO algorithm. The performance of the proposed algorithm is evaluated through simulation. The simulation results reveal that our algorithm performs better than the existing algorithms.

  18. Multicast contention resolution based on time-frequency joint scheduling in elastic optical switching networks

    Science.gov (United States)

    Liu, Huanlin; Li, Yuan; Peng, Han; Huang, Jun; Kong, Deqian

    2017-01-01

    Resolving the optical multicast contention in optical switch node is an effective approach to improve the performance of elastic optical multicast switch. An optical node architecture integrating with output shared all-optical Orthogonal Frequency Division Multiplexing (OFDM) network coding technology and shared feedback fiber delay lines (FDLs) buffer is designed. And a time-frequency joint scheduling strategy (TFJSS) is proposed. In TFJSS, the maximal weighted independent set algorithm is used to select the output packets with no overlapping spectrum among the contending multicast packets. The remaining contention packets are compressed by OFDM network coding with all-optical XOR operation. Hence, the contention is avoided in spectrum domain by encoding the contending unicast/multicast packets and changing the carrier frequency of encoded packets. If the network coding cannot successfully resolve the contending packets, the shared feedback FDLs are called to address the contention in time domain. Compared with the existing node architecture and scheduling algorithm, the simulation results show that the proposed architecture and the TFJSS can reduce the packet loss probability with low delay largely.

  19. Range Detection Multicast Routing Protocol for Mobile Ad-Hoc Networks

    Directory of Open Access Journals (Sweden)

    K. Duraiswamy

    2012-01-01

    Full Text Available Problem statement: Many efforts have been implemented towards the Group membership management on multicast routing in MANETs, but the difficulties associated with Group membership management are still existed. Approach: Maintaining endurance of Group Leader (GL in multicasting routing has been a great challenge to all the protocol having been invented so far. Results: This study provides the RDMP algorithm for persistency of Group Leader within the group. Nodes perform very active in exchanging the Data and Control packet when they mobile within the transmission range. Range Detection Multicast Protocol (RDMP focuses on dynamic topology of nodes and uses detection mechanism based on transmission range within the group. Instead of having a separate external node to monitor on Group leadership, a node within the transmission range acts as a Leadership Track Node (LTN, Group Leader manages the group member with the aid provided by LTN and thus control over head shared among them. LTN keeps track of mobility of Group Leader and send alert message when Group Leader moves out of Transmission range and also holds the list of address of all other Group Leader which are adjacent to it. Routing control packet and data packet are regulated with minimum control over head. Conclusion/Recommendations: Our simulation results under increasing group size demonstrate endurance of Group leader for longer period of time, joining delay for multicast group is very low, normalized control over head and minimizing number of hops in maintain average path length.

  20. Exploiting the In-Network Capabilities of Multicast to Discover Proximate IPTV Channels

    Directory of Open Access Journals (Sweden)

    William Donnelly

    2010-09-01

    Full Text Available IPTV has become the next generation of television due, in part, to its ability to support features that have been lacking in conventional broadcasting—for example, end-user interactivity, personalisation and localisation. Providers are also searching for the most efficient delivery methods to provide the greatest amount of contents at the lowest cost. At present IPTV uses IP multicast to deliver live TV channels in an over-provisioned walled-garden network due to issues of deploying multicast and QoS challenges in the public Internet. However, IPTV is likely to shift into some parts of the public Internet in the future as a managed service. Multicast routing is performed on a per-session destination-address basis so each router maintains a table of all of the multicast addresses to which the content is being forwarded. We exploit this information to discover and join the in-progress channels of geographically proximate users and to create a new incentivised premium service in future IPTV networks called ProxyTV. This approach is expected to minimise network bandwidth requirements as it enables ISPs to optimise bandwidth on their edge networks. This becomes increasingly significant as TV content consumes more and more bandwidth, especially with the onset of HD and 3D capabilities. In this paper, we have presented in detail the concept with the results of a survey and an analysis of network traffic to justify the proposed approach.

  1. A Kind of New Multicast Routing Algorithm for Application of Internet of Things

    Directory of Open Access Journals (Sweden)

    G. Li

    2013-08-01

    Full Text Available Wireless Sensor Networks (WSN is widely used as an effective medium to integrate physical world and information world of Internet of Things (IOT. While keeping energy consumption at a minimal level, WSN requires reliable communication. Multicasting is a general operation performed by the Base Station, where data is to be transmitted to a set of destination nodes. Generally, the packets are routed in a multi-hop approach, where some intermediate nodes are also used for packet forwarding. This problem can be reduced to the well-known Steiner tree problem, which has proven to be NP-complete for deterministic link descriptors and cost functions. In this paper, we propose a novel multicast protocol, named heuristic algorithms for the solution of the Quality of Service (QoS constrained multicast routing problem, with incomplete information in Wireless Sensor Networks (WSN. As information aggregation or randomly fluctuating traffic loads, link measures are considered to be random variables. Simulation results show that the Hop Neural Networks (HNN based heuristics with a properly chosen additive measures can yield to a good solution for this traditionally NP complex problem, when compared to the best multicast algorithms known.

  2. Efficient round-robin multicast scheduling for input-queued switches

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Yu, Hao; Ruepp, Sarah Renée

    2014-01-01

    problem. Using a separate queue for each output port at an input to reduce the HOL blocking, that is, the virtual output queuing discipline, increases the implementation complexity, which limits the scalability. Given the increasing link speed and network capacity, a low-complexity yet efficient multicast...

  3. Joint NC-ARQ and AMC for QoS-Guaranteed Mobile Multicast

    DEFF Research Database (Denmark)

    Toftegaard, Thomas Skjødeberg; Wang, Haibo; Schwefel, Hans-Peter;

    2010-01-01

    In mobile multicast transmissions, the receiver with the worst instantaneous channel condition limits the transmission data rate under the desired Quality-of-Service (QoS) constraints. If Automatic Repeat reQuest (ARQ) schemes are applied, the selection of Adaptive Modulation and Coding (AMC) mod...

  4. QoS multicast routin8 protocol in hierarchical wireless MANET

    Institute of Scientific and Technical Information of China (English)

    LI LaYuan; LI ChunLin

    2008-01-01

    A wireless MANET is s self-configurable network in which mobile, battery-powered devices dynamically create and change the network topology without relying on any intrastructure or administrative support. It offers unique benefits for certain environments, but there are still several open issues to be resolved before realizing these benefits, including QoS routing, multicasting, and mobility management. Specifically, an efficient QoS multicast routing protocol is needed. This paper pre-sents a hierarchical QoS multicast routing protocol (QMRP) for mobile ad hoc networks, it can provide QoS-sensitive routes in a scalable and flexible way, in the network environment with mobility. In the proposed QMRP scheme, each local node only needs to maintain local multicast routing information and/or summary infor-mation of other clusters (or domains) but does not require any global ad hoc net-work states to be maintained. The QMRP also allows any ad hoc group member to join/leave the muIticast group dynamically and supports multiple QoS constraints. This paper presents formal description and main procedures for realizing routing decision process of the QMRP and the proof of correctness and complexity analy-sis of the protocol. The performance measures of QMRP are evaluated using simulation. The simulation results verify the efficiency and availability of QMRP.

  5. Is Light-Tree Structure Optimal for Multicast Routing in Sparse Light Splitting WDM Networks?

    CERN Document Server

    Zhou, Fen; Cousin, Bernard; 10.1109/ICCCN.2009.5235386

    2010-01-01

    To minimize the number of wavelengths required by a multicast session in sparse light splitting wavelength division multiplexing (WDM) networks, a light-hierarchy structure, which occupies the same wavelength on all links, is proposed to span as many destinations as possible. Different from a light-tree, a light-hierarchy accepts cycles, which are used to traverse crosswise a 4-degree (or above) multicast incapable (MI) node twice (or above) and switch two light signals on the same wavelengths to two destinations in the same multicast session. In this paper, firstly, a graph renewal and distance priority light-tree algorithm (GRDP-LT) is introduced to improve the quality of light-trees built for a multicast request. Then, it is extended to compute light-hierarchies. Obtained numerical results demonstrate the GRDP-LT light-trees can achieve a much lower links stress, better wavelength channel cost, and smaller average end-to-end delay as well as diameter than the currently most efficient algorithm. Furthermore...

  6. Joint NC-ARQ and AMC for QoS-Guaranteed Mobile Multicast

    DEFF Research Database (Denmark)

    Wang, Haibo; Schwefel, Hans-Peter; Chu, Xiaoli;

    2010-01-01

    In mobile multicast transmissions, the receiver with the worst instantaneous channel condition limits the transmission data rate under the desired Quality-of-Service (QoS) constraints. If Automatic Repeat reQuest (ARQ) schemes are applied, the selection of Adaptive Modulation and Coding (AMC) mode...

  7. A novel round-robin based multicast scheduling algorithm for 100 Gigabit Ethernet switches

    DEFF Research Database (Denmark)

    Yu, Hao; Ruepp, Sarah Renée; Berger, Michael Stübert

    2010-01-01

    This paper proposes a round-robin based multicast scheduling algorithm for high-speed input-queued switches. Fan-out information of each head-of-line cell is examined by the packet scheduler to form a matrix called Traffic Matrix. A subscheduler for each column executes the round-robin scheduling...

  8. History-based Adaptive Modulation for a Downlink Multicast Channel in OFDMA systems

    DEFF Research Database (Denmark)

    Wang, Haibo; Schwefel, Hans-Peter; Toftegaard, Thomas Skjødeberg

    2008-01-01

    In this paper we investigated the adaptive modulation strategies for Multicast service in orthogonal frequency division multiple access systems. We defined a Reward function as the performance optimization target and developed adaptive modulation strategies to maximize this Reward function. The p...

  9. DEA Multimedia Drug Library: Marijuana

    Science.gov (United States)

    ... DEA Press Room » Multi-Media Library » Image Gallery » Marijuana MARIJUANA To Save Images: First click on the thumbnail ... Save in directory and then click Save. Indoor Marijuana Grow Indoor Marijuana Grow Loose Marijuana Marinol 10mg ...

  10. Multimedia-Video for Learning

    CERN Document Server

    Chua, Kah Hean; Wee, Loo Kang; Tan, Ching

    2015-01-01

    Multimedia engages an audience through a combination of text, audio, still images, animation, video, or interactivity-based content formats. Along this vein, free platforms have been seen to allow budding enthusiasts to create multimedia content. For example, Google sites (Wee, 2012b) offer creative opportunities in website development that enable text insertion, still image, video and animation embedding, along with audio and hyper-interactive links to simulations (Christian & Esquembre, 2012; Wee, 2013; Wee, Goh, & Chew, 2013; Wee, Goh, & Lim, 2013; Wee, Lee, Chew, Wong, & Tan, 2015). This chapter focuses on the video aspect of multimedia, which can be positioned as a component to any effective self-paced on-line lesson that would be available anytime, anywhere via computer or mobile devices. The multimedia video approach aims to help users overcome barriers in creating engaging, effective and meaningful content (Barron & Darling-Hammond, 2008) for teaching and learning in an online envi...

  11. Developer's handbook of interactive multimedia

    CERN Document Server

    Phillips, Robin

    2014-01-01

    New technology is being used more and more in education and providers have to be aware of what is on offer and how it can be used. This practical handbook demonstrates how interactive multimedia can be developed for educational application.

  12. Multimedia content analysis

    CERN Document Server

    Ohm, Jens

    2016-01-01

    This textbook covers the theoretical backgrounds and practical aspects of image, video and audio feature expression, e.g., color, texture, edge, shape, salient point and area, motion, 3D structure, audio/sound in time, frequency and cepstral domains, structure and melody. Up-to-date algorithms for estimation, search, classification and compact expression of feature data are described in detail. Concepts of signal decomposition (such as segmentation, source tracking and separation), as well as composition, mixing, effects, and rendering, are discussed. Numerous figures and examples help to illustrate the aspects covered. The book was developed on the basis of a graduate-level university course, and most chapters are supplemented by problem-solving exercises. The book is also a self-contained introduction both for researchers and developers of multimedia content analysis systems in industry. .

  13. Now Broadcasting in Planck Definition

    Energy Technology Data Exchange (ETDEWEB)

    Hogan, Craig [Fermilab

    2013-07-08

    If reality has finite information content, space has finite fidelity. The quantum wave function that encodes spatial relationships may be limited to information that can be transmitted in a "Planck broadcast", with a bandwidth given by the inverse of the Planck time, about $2\\times 10^{43}$ bits per second. Such a quantum system can resemble classical space-time on large scales, but locality emerges only gradually and imperfectly. Massive bodies are never perfectly at rest, but very slightly and slowly fluctuate in transverse position, with a spectrum of variation given by the Planck time. This distinctive new kind of noise associated with quantum geometry would not have been noticed up to now, but may be detectable in a new kind of experiment.

  14. Dynamic Broadcast Scheduling in DDBMS

    Directory of Open Access Journals (Sweden)

    Babu Santhalingam,

    2011-01-01

    Full Text Available This system will address the problem of online scheduling sequential data objects with the principle of periodicity in the context of dynamic information dissemination. Many modern information applications spread dynamically generated data objects and answer the complex query for retrieving multiple data objects. In dynamic environments, data streams need to be online processed rather than being stored and later retrieved to answer queries. Particularly, data objects are produced dynamically by the information providers, interleaved and disseminated efficiently by the broadcasting servers, and associated sequentially in the client sides. The proposed algorithm with a well-specific gain measure function prominently outperforms the FIFO schedule and is able to minimize the mean service access time to the extent close to the theoretical optimum.

  15. An Improved Multicast Routing Algorithm%一个改进的多播路由算法

    Institute of Scientific and Technical Information of China (English)

    蒋廷耀; 李庆华

    2004-01-01

    Multicasting is a communication service that allows an application to efficiently transmit copies of data packets to a set of destination nodes. The problem of finding a minimum cost multicast tree can be formulated as a minimum Steiner tree problem in networks, which is NP-completeness. MPH (minimum path cost heuristic) algorithm is a famous solution to this problem. In this paper,we present a novel solution TPMPH (two phase minimum path cost heuristic) to improve the MPH by generating the nodes and the edges of multicast tree separately. The cost of multicast tree generated by the proposed algorithm with the same time as MPH is no more than that of MPH in the worst case. Extensive simulation results show that TPMPH can effectively improve the performance on MPH, and performs better in large-scale networks and wireless networks.

  16. Near-field self-interference cancellation and quality of service multicast beamforming in full-duplex

    Science.gov (United States)

    Wu, Fei; Shao, Shihai; Tang, Youxi

    2016-10-01

    To enable simultaneous multicast downlink transmit and receive operations on the same frequency band, also known as full-duplex links between an access point and mobile users. The problem of minimizing the total power of multicast transmit beamforming is considered from the viewpoint of ensuring the suppression amount of near-field line-of-sight self-interference and guaranteeing prescribed minimum signal-to-interference-plus-noise-ratio (SINR) at each receiver of the multicast groups. Based on earlier results for multicast groups beamforming, the joint problem is easily shown to be NP-hard. A semidefinite relaxation (SDR) technique with linear program power adjust method is proposed to solve the NP-hard problem. Simulation shows that the proposed method is feasible even when the local receive antenna in nearfield and the mobile user in far-filed are in the same direction.

  17. Experimental Analysis of the Fault Tolerance of the PIM-SM IP Multicast Routing Protocol under GNS3

    Directory of Open Access Journals (Sweden)

    Gábor Lencse

    2014-06-01

    Full Text Available PIM-SM is the most commonly used IP multicast routing protocol in IPTV systems. Its fault tolerance is examined by experimenting on a mesh topology multicast test network built up by Cisco routers under GNS3. Different fault scenarios are played and different parameters of the PIM-SM and of the OSPF protocols are examined if they influence and how they influence the outage time of an IPTV service. The failure of the Rendezvous Point (RP of the given IP multicast group as well as the complete failure of a router in the media forwarding path of the multicast stream are examined. A method is given how the service outage time caused by the complete failure of a router can be limited by an appropriate choice of the Dead Interval parameter of OSPF.

  18. Demonstration of obstruction-free data-carrying N-fold Bessel modes multicasting from a single Gaussian mode.

    Science.gov (United States)

    Zhu, Long; Wang, Jian

    2015-12-01

    By designing and optimizing complex phase pattern combining with axicon phase distribution, we report data multicasting from a single Gaussian mode to multiple Bessel modes using a single phase-only spatial light modulator. Under the obstructed path conditions, obstruction-free data-carrying N-fold Bessel modes multicasting is demonstrated in the experiment. We also experimentally study N-fold multicasting of a 20 Gbit/s quadrature phase-shift keying signal from a single Gaussian mode to multiple Bessel modes and measure the link performance. All the multicasted Bessel modes show relatively low crosstalk from their neighboring modes and achieve a bit-error rate of less than 1e-3.

  19. Digital libraries: A testbed for multimedia technology

    Institute of Scientific and Technical Information of China (English)

    ZHUANG Yue-ting

    2005-01-01

    A distinguishing feature of a digital library is that it has Terabyte volumes of multimedia resources. One challenge for researchers in the field of multimedia is to find a testbed for showing the potentials of multimedia technologies such as video summarization, semantic annotation, multimedia cross indexing and retrieval, and etc. Deeper research and wider applications of digital libraries revealed their indispensable role as testbed for multimedia technologies. This paper presents challenging issues of some key techniques used in digital libraries and their specific needs for multimedia technologies.

  20. Broadcast satellite service: The international dimension

    Science.gov (United States)

    Samara, Noah

    1991-09-01

    The dawn of the 1990's has witnessed the birth of a new satellite service - satellite sound broadcasting. This new service is characterized by digital transmission at data rates up to 256 kb/s from satellites in geostationary orbit to small, low-cost, mobile and portable receivers. The satellite sound broadcasting service is a logical step beyond navigation satellite service, such as that provided by the GPS Navstar system. The mass market appeal of satellite sound broadcasting in the area of lightsat technology and low-cost digital radios has greatly facilitated the financing of this type of space service.

  1. Classical codes for quantum broadcast channels

    CERN Document Server

    Savov, Ivan

    2011-01-01

    We discuss two techniques for transmitting classical information over quantum broadcast channels. The first technique is a quantum generalization of the superposition coding scheme for the classical broadcast channel. We use a quantum simultaneous nonunique decoder and obtain a simpler proof of the rate region recently published by Yard et al. in independent work. Our second result is a quantum Marton coding scheme, which gives the best known achievable rate region for quantum broadcast channels. Both results exploit recent advances in quantum simultaneous decoding developed in the context of quantum interference channels.

  2. Emergency Broadcast System Based On GIS

    Science.gov (United States)

    Junfeng, Kang; Baoyu, Wang; Xueying, Jiang; Xiaosheng, Liu

    2017-02-01

    Nowadays, disaster occurs more and more frequently, which brings huge losses to the society. Presented a GIS based emergency broadcast system (GIS-EBS), to provide rapid, accurate information to the public, can reduce the people’s losses maximum. Different from the traditional radio data system (RDS), by adding broadcasting terminal control instruction on the FM signal, GIS-EBS extended the RDS protocol, which can control each radio terminal’s state. And through the extended RDS protocol, GIS-EBS can broadcast and release the emergency information to the right place and the people most in need in the shortest time.

  3. Energy-Efficient Multicast Transmission for Underlay Device-to-Device Communications: A Social-Aware Perspective

    Directory of Open Access Journals (Sweden)

    Fan Jiang

    2017-01-01

    Full Text Available In this paper, by utilizing the social relationships among mobile users, we present a framework of energy-efficient cluster formation and resource allocation for multicast D2D transmission. In particular, we first deal with D2D multicast cluster/group formation strategy from both physical distance and social trust level. Then we aim to maximize the overall energy-efficiency of D2D multicast groups through resource allocation and power control scheme, which considers the quality-of-service (QoS requirements of both cellular user equipment and D2D groups. A heuristic algorithm is proposed to solve above energy-efficiency problem with less complexity. After that, considering the limited battery capacity of mobile users, we propose an energy and social aware cluster head update algorithm, which incorporates both the energy constraint and social centrality measurement. Numerical results indicate that the proposed social-tie based D2D multicast group formation and update algorithm form a multicast group in an energy efficient way. Moreover, the proposed resource and power allocation scheme achieves better energy efficiency in terms of throughput per energy consumption. These results show that, by exploiting social domain information, underlay D2D multicast transmission has high practical potential in saving the source on wireless links and in the backhaul.

  4. 37 CFR 253.2 - Definition of public broadcasting entity.

    Science.gov (United States)

    2010-07-01

    ... broadcasting entity. 253.2 Section 253.2 Patents, Trademarks, and Copyrights COPYRIGHT OFFICE, LIBRARY OF... CONNECTION WITH NONCOMMERCIAL EDUCATIONAL BROADCASTING § 253.2 Definition of public broadcasting entity. As used in this part, the term public broadcasting entity means a noncommercial educational...

  5. 78 FR 78318 - Television Broadcasting Services; Oklahoma City, Oklahoma

    Science.gov (United States)

    2013-12-26

    ... COMMISSION 47 CFR Part 73 Television Broadcasting Services; Oklahoma City, Oklahoma AGENCY: Federal... filed by Family Broadcasting Group, Inc. (``Family Broadcasting''), the licensee of station KSBI(TV... voluntary relocation agreement with Lower 700 MHz A Block licensees. Family Broadcasting has entered...

  6. 75 FR 9859 - Television Broadcasting Services; Beaumont, TX

    Science.gov (United States)

    2010-03-04

    ... COMMISSION 47 CFR Part 73 Television Broadcasting Services; Beaumont, TX AGENCY: Federal Communications... Freedom Broadcasting of Texas (``Freedom Broadcasting''), the licensee of KFDM(TV), channel 21, Beaumont, Texas. Freedom Broadcasting requests ] the substitution of channel 25 for channel 21 at Beaumont....

  7. 47 CFR 73.597 - FM stereophonic sound broadcasting.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false FM stereophonic sound broadcasting. 73.597 Section 73.597 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES... broadcasting. A noncommercial educational FM broadcast station may, without specific authority from the...

  8. Non-Degenerate Four-Wave Mixing in a Silicon Nanowire and its Application for One-to-Six WDM Multicasting

    DEFF Research Database (Denmark)

    Pu, Minhao; Hu, Hao; Ji, Hua

    2011-01-01

    We present WDM multicasting based on non-degenerate four-wave mixing in a silicon nanowire. A one-to-six phase-preserving wavelength multicasting of 10 Gb/s differential phase-shift-keying data is experimentally demonstrated with bit-error rate measurements.......We present WDM multicasting based on non-degenerate four-wave mixing in a silicon nanowire. A one-to-six phase-preserving wavelength multicasting of 10 Gb/s differential phase-shift-keying data is experimentally demonstrated with bit-error rate measurements....

  9. Overview of multimedia content protection in consumer electronics devices

    Science.gov (United States)

    Eskicioglu, Ahmet M.; Delp, Edward J., III

    2000-05-01

    A digital home network is a cluster of digital audio/visual (A/V) devices including set-top boxes, TVs, VCRs, DVD players, and general-purpose computing devices such as personal computers. The network may receive copyrighted digital multimedia content from a number of sources. This content may be broadcast via satellite or terrestrial systems, transmitted by cable operators, or made available as prepackaged media (e.g., a digital tape or a digital video disc). Before releasing their content for distribution, the content owners may require protection by specifying access conditions. Once the content is delivered to the consumer, it moves across home the network until it reaches its destination where it is stored or displayed. A copy protection system is needed to prevent unauthorized access to bit streams in transmission from one A/V device to another or while it is in storage on magnetic or optical media. Recently, two fundamental groups of technologies, encryption and watermarking, have been identified for protecting copyrighted digital multimedia content. This paper is an overview of the work done for protecting content owners' investment in intellectual property.

  10. History and Multimedia Technology. Media Corner.

    Science.gov (United States)

    Mitchell-Powell, Brenda, Ed.

    1994-01-01

    Contends that, although multimedia technology offers new options for history instruction, its value depends on the consistency, reliability, and convenience of operational methods. Provides reviews of three recommended and one not recommended multimedia packages. (CFR)

  11. History and Multimedia Technology. Media Corner.

    Science.gov (United States)

    Mitchell-Powell, Brenda, Ed.

    1994-01-01

    Contends that, although multimedia technology offers new options for history instruction, its value depends on the consistency, reliability, and convenience of operational methods. Provides reviews of three recommended and one not recommended multimedia packages. (CFR)

  12. Injection molded optical backplane for broadcast architecture

    Science.gov (United States)

    Rosenberg, Paul; Mathai, Sagi; Sorin, Wayne V.; McLaren, Moray; Straznicky, Joseph; Panotopoulos, Georgios; Warren, David; Morris, Terry; Tan, Michael R. T.

    2012-01-01

    A low cost, blind mate, injection molded optical backplane is presented. The optical backplane is comprised of 12 channel optical broadcast buses, operating at 10Gbps/channel with six blindmate optical output ports spaced 1U apart.

  13. On Neologism in Broadcast News Reporting

    Institute of Scientific and Technical Information of China (English)

    吕慧

    2014-01-01

    Based on the neologism in the broadcast news reporting, this paper will introduce different kinds of the most frequently used words today, including the extended meanings of the conventional words and new words created by word formation.

  14. 8 CFR 204.13 - How can the International Broadcasting Bureau of the United States Broadcasting Board of...

    Science.gov (United States)

    2010-01-01

    ... 8 Aliens and Nationality 1 2010-01-01 2010-01-01 false How can the International Broadcasting Bureau of the United States Broadcasting Board of Governors petition for a fourth preference special... Broadcasting Bureau of the United States Broadcasting Board of Governors petition for a fourth...

  15. Optimal Broadcasting of Mixed Equatorial Qubits

    Institute of Scientific and Technical Information of China (English)

    YU Zong-Wen

    2009-01-01

    We derive an optimal 2→M phase-covariant quantum broadcasting of mixed equatorial qubits.This quantum broadcasting is optimal in the sense that the shrinking factor between the input and the output single qubit achieves the upper bound.The result shows that we can copy two identical mixed equatorial qubits with the same quality as those of two identical pure equatorial states.

  16. An SP-Hill layered broadcast cryptosystem

    Science.gov (United States)

    Spencer, M. E.; Tavares, S. E.

    A new type of cryptosystem with applications in broadcast communications and database systems is described. The scheme combines various elements of both SP-networks and Hill broadcast encryption systems. The theoretical basis for the encryption technique is described in a series of equations and the results of a preliminary production process complexity test are presented. The results of the test indicate that the scheme performs well cryptographically and that it represents a significant advance over conventional encryption systems.

  17. Dual-scale multimedia dynamic synchronization model

    Institute of Scientific and Technical Information of China (English)

    李乃祥

    2009-01-01

    Multimedia synchronization is the key technology in application of distributed multimedia.Solution of synchronization conflicts insides and among streams as well as that of user interaction,synchronization granularity refinement and synchronization precision improvement remain great challenges although great efforts have been invested by the academic circle.The construction method of a dual-scale dynamic synchronous model of multimedia presented in this article realizes multimedia synchronization on two sca...

  18. Multimedia database retrieval technology and applications

    CERN Document Server

    Muneesawang, Paisarn; Guan, Ling

    2014-01-01

    This book explores multimedia applications that emerged from computer vision and machine learning technologies. These state-of-the-art applications include MPEG-7, interactive multimedia retrieval, multimodal fusion, annotation, and database re-ranking. The application-oriented approach maximizes reader understanding of this complex field. Established researchers explain the latest developments in multimedia database technology and offer a glimpse of future technologies. The authors emphasize the crucial role of innovation, inspiring users to develop new applications in multimedia technologies

  19. Multimedia security watermarking, steganography, and forensics

    CERN Document Server

    Shih, Frank Y

    2012-01-01

    Multimedia Security: Watermarking, Steganography, and Forensics outlines essential principles, technical information, and expert insights on multimedia security technology used to prove that content is authentic and has not been altered. Illustrating the need for improved content security as the Internet and digital multimedia applications rapidly evolve, this book presents a wealth of everyday protection application examples in fields including multimedia mining and classification, digital watermarking, steganography, and digital forensics. Giving readers an in-depth overview of different asp

  20. Dynamic multimedia annotation tool

    Science.gov (United States)

    Pfund, Thomas; Marchand-Maillet, Stephane

    2001-12-01

    Annotating image collections is crucial for different multimedia applications. Not only this provides an alternative access to visual information but it is a critical step to perform the evaluation of content-based image retrieval systems. Annotation is a tedious task so that there is a real need for developing tools that lighten the work of annotators. The tool should be flexible and offer customization so as to make the annotator the most comfortable. It should also automate the most tasks as possible. In this paper, we present a still image annotation tool that has been developed with the aim of being flexible and adaptive. The principle is to create a set of dynamic web pages that are an interface to a SQL database. The keyword set is fixed and every image receives from concurrent annotators a set of keywords along with time stamps and annotator Ids. Each annotator has the possibility of going back and forth within the collection and its previous annotations. He is helped by a number of search services and customization options. An administrative section allows the supervisor to control the parameter of the annotation, including the keyword set, given via an XML structure. The architecture of the tool is made flexible so as to accommodate further options through its development.

  1. Network Provisioning Using Multimedia Aggregates

    Directory of Open Access Journals (Sweden)

    Joan Vila-Carbó

    2008-01-01

    Full Text Available Multimedia traffic makes network provisioning a key issue. Optimal provisioning of network resources is crucial for reducing the service cost of multimedia transmission. Multimedia traffic requires not only provisioning bandwidth and buffer resources in the network but also guaranteeing a given maximum end-to-end delay. In this paper we present methods and tools for the optimal dimensioning of networks based on multimedia aggregates. The proposed method minimises the network resources reservations of traffic aggregates providing a bounded delay. The paper also introduces several methods to generate multimedia traffic aggregation using real video traces. The method is evaluated using a network topology based on the European GÉANT network. The results of these simulations allow us to discover the relationship between a required delay and the necessary bandwidth reservation (or the achievable utilisation limit. An interesting conclusion of these scenarios is that, following several recommendations, the network utilisation can reach values of around 80% or higher.

  2. Optical links in handheld multimedia devices

    Science.gov (United States)

    van Geffen, S.; Duis, J.; Miller, R.

    2008-04-01

    Ever emerging applications in handheld multimedia devices such as mobile phones, laptop computers, portable video games and digital cameras requiring increased screen resolutions are driving higher aggregate bitrates between host processor and display(s) enabling services such as mobile video conferencing, video on demand and TV broadcasting. Larger displays and smaller phones require complex mechanical 3D hinge configurations striving to combine maximum functionality with compact building volumes. Conventional galvanic interconnections such as Micro-Coax and FPC carrying parallel digital data between host processor and display module may produce Electromagnetic Interference (EMI) and bandwidth limitations caused by small cable size and tight cable bends. To reduce the number of signals through a hinge, the mobile phone industry, organized in the MIPI (Mobile Industry Processor Interface) alliance, is currently defining an electrical interface transmitting serialized digital data at speeds >1Gbps. This interface allows for electrical or optical interconnects. Above 1Gbps optical links may offer a cost effective alternative because of their flexibility, increased bandwidth and immunity to EMI. This paper describes the development of optical links for handheld communication devices. A cable assembly based on a special Plastic Optical Fiber (POF) selected for its mechanical durability is terminated with a small form factor molded lens assembly which interfaces between an 850nm VCSEL transmitter and a receiving device on the printed circuit board of the display module. A statistical approach based on a Lean Design For Six Sigma (LDFSS) roadmap for new product development tries to find an optimum link definition which will be robust and low cost meeting the power consumption requirements appropriate for battery operated systems.

  3. Towards Interactive, Intelligent, and Integrated Multimedia Analytics

    NARCIS (Netherlands)

    Zahálka, J.; Worring, M.; Chen, M.; Ebert, D.; North, C.

    2014-01-01

    The size and importance of visual multimedia collections grew rapidly over the last years, creating a need for sophisticated multimedia analytics systems enabling large-scale, interactive, and insightful analysis. These systems need to integrate the human's natural expertise in analyzing multimedia

  4. Standards of Multimedia Graphic Design in Education

    Science.gov (United States)

    Aldalalah, Osamah Ahmad; Ababneh, Ziad Waleed Mohamed

    2015-01-01

    This study aims to determine Standards of Multimedia Graphic Design in Education through the analysis of the theoretical basis and previous studies related to this subject. This study has identified the list of standards of Multimedia, Graphic Design, each of which has a set indicator through which the quality of Multimedia can be evaluated in…

  5. Multimedia Search Engines : Concept, Performance, and Types

    OpenAIRE

    Sayed Rabeh Sayed

    2005-01-01

    A Research about multimedia search engines, it starts with definition of search engines at general and multimedia search engines, then explains how they work, and divided them into: Video search engines, Images search engines, and Audio search engines. Finally, it reviews a samples to multimedia search engines.

  6. Security Management in a Multimedia System

    Science.gov (United States)

    Rednic, Emanuil; Toma, Andrei

    2009-01-01

    In database security, the issue of providing a level of security for multimedia information is getting more and more known. For the moment the security of multimedia information is done through the security of the database itself, in the same way, for all classic and multimedia records. So what is the reason for the creation of a security…

  7. Increasing Student Learning through Multimedia Projects.

    Science.gov (United States)

    Simkins, Michael; Cole, Karen; Tavalin, Fern; Means, Barbara

    This book discusses enhancing student achievement through project-based learning with multimedia. Chapter 1 describes project-based multimedia learning. Chapter 2 presents a multimedia primer, including the five basic types of media objects (i.e., images, text, sound, motion, and interactivity). Chapter 3 addresses making a real-world connection,…

  8. Multimedia Search Engines : Concept, Performance, and Types

    Directory of Open Access Journals (Sweden)

    Sayed Rabeh Sayed

    2005-12-01

    Full Text Available A Research about multimedia search engines, it starts with definition of search engines at general and multimedia search engines, then explains how they work, and divided them into: Video search engines, Images search engines, and Audio search engines. Finally, it reviews a samples to multimedia search engines.

  9. Multimedia signal coding and transmission

    CERN Document Server

    Ohm, Jens-Rainer

    2015-01-01

    This textbook covers the theoretical background of one- and multidimensional signal processing, statistical analysis and modelling, coding and information theory with regard to the principles and design of image, video and audio compression systems. The theoretical concepts are augmented by practical examples of algorithms for multimedia signal coding technology, and related transmission aspects. On this basis, principles behind multimedia coding standards, including most recent developments like High Efficiency Video Coding, can be well understood. Furthermore, potential advances in future development are pointed out. Numerous figures and examples help to illustrate the concepts covered. The book was developed on the basis of a graduate-level university course, and most chapters are supplemented by exercises. The book is also a self-contained introduction both for researchers and developers of multimedia compression systems in industry.

  10. Performance improvement of an optical network providing services based on multicast

    CERN Document Server

    Reinhard, Vincent; Tomasik, Joanna; Barth, Dominique; Weisser, Marc-Antoine

    2011-01-01

    Operators of networks covering large areas are confronted with demands from some of their customers who are virtual service providers. These providers may call for the connectivity service which fulfils the specificity of their services, for instance a multicast transition with allocated bandwidth. On the other hand, network operators want to make profit by trading the connectivity service of requested quality to their customers and to limit their infrastructure investments (or do not invest anything at all). We focus on circuit switching optical networks and work on repetitive multicast demands whose source and destinations are {\\em \\`a priori} known by an operator. He may therefore have corresponding trees "ready to be allocated" and adapt his network infrastructure according to these recurrent transmissions. This adjustment consists in setting available branching routers in the selected nodes of a predefined tree. The branching nodes are opto-electronic nodes which are able to duplicate data and retransmit...

  11. QoS multicast routing scheme using QGA in IP/DWDM networks

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This article studies multi-constraints least-cost multicast routing problem in internet protocol over dense wavelength division multiplexing (IP/DWDM) networks. To address this problem, an individual-difference-based quantum genetic algorithm (IDQGA) is proposed. This algorithm considers individual differences among chromosomes by introducing an adaptive rotation angle step determination scheme and a grouping-based quantum mutation operation. Simulations are conducted over network topologies. The results indicate that compared with other heuristic algorithms, IDQGA has better optimal performance on solving quality of service (QoS) multicast routing problem in IP/DWDM networks and is characterized by strong robustness, high success ratio and excellent capability on global searching.

  12. On-Demand Multicasting in Ad-hoc Networks: Performance Evaluation of AODV, ODMRP and FSR

    CERN Document Server

    Rajendiran, M

    2011-01-01

    Adhoc networks are characterized by connectivity through a collection of wireless nodes and fast changing network topology. Wireless nodes are free to move independent of each other which makes routing much difficult. This calls for the need of an efficient dynamic routing protocol. Mesh-based multicast routing technique establishes communications between mobile nodes of wireless adhoc networks in a faster and efficient way. In this article the performance of prominent on-demand routing protocols for mobile adhoc networks such as ODMRP (On Demand Multicast Routing Protocol), AODV (Adhoc on Demand Distance Vector) and FSR (Fisheye State Routing protocol) was studied. The parameters viz., average throughput, packet delivery ration and end-to-end delay were evaluated. From the simulation results and analysis, a suitable routing protocol can be chosen for a specified network. The results show that the ODMRP protocol performance is remarkably superior as compared with AODV and FSR routing protocols. Keywords: MANE...

  13. Cost of Multicast Logical Key Tree Based on Hierarchical Data Processing

    Institute of Scientific and Technical Information of China (English)

    ZHOU Fucai; XU Jian; LI Ting

    2006-01-01

    How to design a multicast key management system with high performance is a hot issue now. This paper will apply the idea of hierarchical data processing to construct a common analytic model based on directed logical key tree and supply two important metrics to this problem: re-keying cost and key storage cost. The paper gives the basic theory to the hierarchical data processing and the analyzing model to multicast key management based on logical key tree. It has been proved that the 4-ray tree has the best performance in using these metrics. The key management problem is also investigated based on user probability model, and gives two evaluating parameters to re-keying and key storage cost.

  14. Two Novel Tunnel-based Ring Protection Switching for MPLS-TP Multicast Services

    DEFF Research Database (Denmark)

    Zhang, Jiang; Fu, Rong; Yu, Hao;

    2011-01-01

    This paper investigates and compares the schemes suggested by the ITU and the IETF for MPLS-TP ring protection, and proposes two MPLS-TP ring protections to ensure reliability of MPLS-TP multicast services. The introduced ring protection schemes are named, the SPME-based-Wrapping protection scheme...... and the SPME-based-ROM-Wrapping protection scheme, both of which aim at retaining the advantages of previous MPSL-TP ring protections and avoiding limitations. In the paper, the requirements of designing an efficient and reliable MPLS-TP ring protection, for instance with respect to label consumption......, bandwidth utilization and operation complexity are well considered and also set concrete evaluating criteria for new proposed MPLS-TP ring protection schemes for multicast services....

  15. Energy based reliable multicast routing protocol for packet forwarding in MANET

    Directory of Open Access Journals (Sweden)

    S. Gopinath

    2015-06-01

    Full Text Available Mobile Ad hoc Network consists of mobile nodes without any assisting infrastructure. Mobility of nodes causes network partition. This leads to heavy overhead and less packet forwarding ratio. In this research work, Residual Energy based Reliable Multicast Routing Protocol (RERMR is proposed to attain more network lifetime and increased packet delivery and forwarding rate. A multicast backbone is constructed to achieve more stability based on node familiarity and trustable loop. Reliable path criterion is estimated to choose best reliable path among all available paths. Data packets will be forwarded once the reliable path is chosen. We have also demonstrated that residual energy of paths aids to provide maximum network lifetime. Based on the simulation results, the proposed work achieves better performance than previous protocols in terms of packet reliability rate, network stability rate, end to end delay, end to end transmission and communication overhead.

  16. QoS-Based Dynamic Multicast Routing Design Using Genetic Algorithms

    Institute of Scientific and Technical Information of China (English)

    YUANYouwei; YANLamei

    2004-01-01

    This paper addresses the problem of determining minimum cost paths to nodes in a Multicast group satisfying delay bounds and delay variation bounds. This study explores the use of Genetic algorithms (GAs) for solving the multicast routing problems when multiple Quality of services (QoS) requirements are presented. Our simulation results indicate that it is critical to select a suitable representation method and a set of appropriate parameters in order to obtain good performance. For a medium network, the probability from 0.02 to 0.2 seems to work better than those of too small or too large. As compared with the other optimal algorithm, the proposed algorithm gives better performance in terms of the success rate, the tree cost, the number of exchanged messages and the convergence time.

  17. Impact of Physical Layer Jamming on Wireless Sensor Networks with Shadowing and Multicasting

    Directory of Open Access Journals (Sweden)

    Nischay Bahl

    2012-07-01

    Full Text Available This paper analyzes the impact of a physical layer jamming on the performance of wireless sensor networks by performing exhaustive comparative simulations using multicasting and by employing varying intensity of shadowing (constant and log normal. Comprehensive result analysis reveals that jamming drastically degrades the legitimate traffic throughput in a network, and, the constant shadowing approach is a better fit for a static network, both, under static as well as mobile jammer environments, as compared to the log normal one. An improvement in sink-node packet delivery ratio by 15.02 % and 16.58 % was observed with static and mobile jammer environments respectively, under multicasting and constant shadowing mean of 8.0. Further, average sink-node packet delivery ratio with constant shadowing shows an improvement of 4.15% and 5.94%, using static and mobile jammer environment respectively, in comparison to the values obtained under log normal shadowing based network.

  18. SM_TCP: a new reliable multicast transport protocol for satellite IP networks

    Science.gov (United States)

    Liu, Gongliang; Gu, Xuemai; Li, Shizhong

    2005-11-01

    A new reliable multicast transport protocol SM_TCP is proposed for satellite IP networks in this paper. In SM_TCP, the XOR scheme with the aid of on-board buffering and processing is used for error recovery and an optimal retransmission algorithm is designed, which can reduce the recovery time by half of the RTT and minimize the number of retransmissions. In order to avoid the unnecessary decrease of congestion window in the high BER satellite channels, the occupied buffer sizes at bottlenecks are measured in adjusting the congestion window, instead of depending on the packet loss information. The average session rate of TCP sessions and of multicast sessions passing through the satellite are also measured and compared in adjusting the congestion window, which contributes to bandwidth fairness. Analysis and simulation results show fairness with TCP flows and scalability.

  19. Wurf.it: A Network Coding Reliable Multicast Content Streaming Solution - ns-3 Simulations and Implementation

    DEFF Research Database (Denmark)

    Hernandez, Nestor; Pihl, Jeppe; Heide, Janus

    One of the proven benets of Network Coding (NC) is to achieve the data capacity for multicast networks. However, even though there has been a signicant amount of research in this area, potentials demonstrators of these capabilities have not been widely shown or deployed. Thus, in this work we...... present a set of pre-computed ns-3 simulations to model the behaviour of Wurf.it, a Random Linear Network Coding (RLNC)-based reliable multicast solution for content distribution with cross-platform support. Wurf.it is based on Kodo, a C++11 network coding library that provides the primitive encoding...... demonstrator consists of stored simulations with ns-3 in a laptop and a Wurf.it implementation within a WiFi network. For the implementation, a video content from a mobile camera is distributed with low delay using SCORE to a set of heterogenous receivers (e.g. dierent platforms). Use cases of Wurf.it are mild...

  20. Specification and Design of a Fault Recovery Model for the Reliable Multicast Protocol

    Science.gov (United States)

    Montgomery, Todd; Callahan, John R.; Whetten, Brian

    1996-01-01

    The Reliable Multicast Protocol (RMP) provides a unique, group-based model for distributed programs that need to handle reconfiguration events at the application layer. This model, called membership views, provides an abstraction in which events such as site failures, network partitions, and normal join-leave events are viewed as group reformations. RMP provides access to this model through an application programming interface (API) that notifies an application when a group is reformed as the result of a some event. RMP provides applications with reliable delivery of messages using an underlying IP Multicast media to other group members in a distributed environment even in the case of reformations. A distributed application can use various Quality of Service (QoS) levels provided by RMP to tolerate group reformations. This paper explores the implementation details of the mechanisms in RMP that provide distributed applications with membership view information and fault recovery capabilities.

  1. 75 FR 17874 - Digital Audio Broadcasting Systems and Their Impact on the Terrestrial Radio Broadcast Service

    Science.gov (United States)

    2010-04-08

    ... of 18 broadcasters that operate over 1200 commercial and noncommercial educational (NCE) FM radio... commercial, religious, educational, and other radio stations.\\11\\ Radio broadcasting stations which primarily... Analyzer Database as of February 19, 2009, about 10,600 (96 percent) of 11,050 commercial radio stations...

  2. Multimedia watermarking techniques and applications

    CERN Document Server

    Kirovski, Darko

    2006-01-01

    Intellectual property owners must continually exploit new ways of reproducing, distributing, and marketing their products. However, the threat of piracy looms as a major problem with digital distribution and storage technologies. Multimedia Watermarking Techniques and Applications covers all current and future trends in the design of modern systems that use watermarking to protect multimedia content. Containing the works of contributing authors who are worldwide experts in the field, this volume is intended for researchers and practitioners, as well as for those who want a broad understanding

  3. Multimedia authentication for copyright protection

    Science.gov (United States)

    Yin, Mingsheng

    2017-06-01

    Multimedia contents are easy to be copied and modified, so it is important to use authentication technology to ensure reliability and copyright security. Multimedia authentication technology is usually divided into digital signature and digital watermarking. In this paper, we introduce some basic image and video authentication technology, such as PCA algorithm and image signature method based on DCT coefficient, LSB -based digital image watermark, SVD-based digital image watermark, and video watermark. Through these digital content security technology, digital contents can be ensured security

  4. Core-based Shared Tree Multicast Routing Algorithms for LEO Satellite IP Networks

    Institute of Scientific and Technical Information of China (English)

    Cheng Lianzhen; Zhang Jun; Liu Kai

    2007-01-01

    A new core-based shared tree algorithm, viz core-cluster combination-based shared tree (CCST) algorithm and the weighted version (i.e. w-CCST algorithm) are proposed in order to resolve the channel resources waste problem in typical source-based multicast routing algorithms in low earth orbit (LEO) satellite IP networks. The CCST algorithm includes the dynamic approximate center (DAC)core selection method and the core-cluster combination multicast route construction scheme. Without complicated onboard computation,the DAC method is uniquely developed for highly dynamic networks of periodical and regular movement. The core-cluster combination method takes core node as the initial core-cluster, and expands it stepwise to construct an entire multicast tree at the lowest tree cost by a shortest path scheme between the newly-generated core-cluster and surplus group members, which results in great bandwidth utilization.Moreover, the w-CCST algorithm is able to strike a balance between performance of tree cost and that of end-to-end propagation delay by adjusting the weighted factor to meet strict end-to-end delay requirements of some real-time multicast services at the expense of a slight increase in tree cost. Finally, performance comparison is conducted between the proposed algorithms and typical algorithms in LEO satellite IP networks. Simulation results show that the CCST algorithm significantly decreases the average tree cost against to the others, and also the average end-to-end propagation delay of w-CCST algorithm is lower than that of the CCST algorithm.

  5. Bulk data transfer distributer: a high performance multicast model in ALMA ACS

    Science.gov (United States)

    Cirami, R.; Di Marcantonio, P.; Chiozzi, G.; Jeram, B.

    2006-06-01

    A high performance multicast model for the bulk data transfer mechanism in the ALMA (Atacama Large Millimeter Array) Common Software (ACS) is presented. The ALMA astronomical interferometer will consist of at least 50 12-m antennas operating at millimeter wavelength. The whole software infrastructure for ALMA is based on ACS, which is a set of application frameworks built on top of CORBA. To cope with the very strong requirements for the amount of data that needs to be transported by the software communication channels of the ALMA subsystems (a typical output data rate expected from the Correlator is of the order of 64 MB per second) and with the potential CORBA bottleneck due to parameter marshalling/de-marshalling, usage of IIOP protocol, etc., a transfer mechanism based on the ACE/TAO CORBA Audio/Video (A/V) Streaming Service has been developed. The ACS Bulk Data Transfer architecture bypasses the CORBA protocol with an out-of-bound connection for the data streams (transmitting data directly in TCP or UDP format), using at the same time CORBA for handshaking and leveraging the benefits of ACS middleware. Such a mechanism has proven to be capable of high performances, of the order of 800 Mbits per second on a 1Gbit Ethernet network. Besides a point-to-point communication model, the ACS Bulk Data Transfer provides a multicast model. Since the TCP protocol does not support multicasting and all the data must be correctly delivered to all ALMA subsystems, a distributer mechanism has been developed. This paper focuses on the ACS Bulk Data Distributer, which mimics a multicast behaviour managing data dispatching to all receivers willing to get data from the same sender.

  6. Survey of Unicast and Multicast Scheduling Algorithms for High Speed Input Queued Switch with Crossbar

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The performance of ATM switches are mainly influenced by switching fabric and scheduling algorithms. Input buffered switches have the strong advantage of efficient crossbar usage. This paper presents an input-queued crossbar switches fabric supporting high speed switching, analyzes the scheduling algorithms for unicast trafficts and multicast traffic based on virtual output queueing (VOQ).Focusing on their performance issues, some typical schedulers are compared.

  7. Can broadcasting make a difference?

    Science.gov (United States)

    Lozare, B V

    1989-01-01

    Communication has untapped potential as a catalyst for community power in developing countries. Greater clarity is needed, however, on the channels of communication that will best integrate the contributions of diverse private and public agencies to meeting development needs. Also needed is a greater emphasis on strategic rather than technical aspects of communication. Most studies of communication have focused on the individual radio listener or television viewer, thereby ignoring the influence of broader forces. A concern for psychological determinants of decision making has led to a neglect of systemic factors. Another major error has been the failure to design longitudinal studies, or at least to collect information at 2 points in time. All of these observations point to a need to study power (economic, political, and social) as a crucial variable in understanding development. Moreover, there is a need for more attention to the role and impact of broadcasting on conflict management--an approach that requires abandoning traditional consensus models of communication. Yet another problem has been blind acceptance of the assumption that development communication and development support communication are unitary concepts that are universally applicable in all countries, all social and cultural contexts, and all development conditions. This unitary approach leads to the false conclusion that there is a grand model of development, and all communication personnel have to do is to see how radio and television fit into this conceptual framework. Finally, there has been a failure to appreciate fully the magnitude of poverty. If true development (defined as the capability of a people to go from where they are to where they want to be) is to occur, these strategic issues must be given serious attention.

  8. International Conference on Multimedia and Ubiquitous Engineering

    CERN Document Server

    Chen, Shu-Ching; Gil, Joon-Min; Yen, Neil; Multimedia and Ubiquitous Engineering

    2014-01-01

    The aims of these proceedings are to provide a complete coverage of the areas outlined, and to bring together researchers from academic and industry to share ideas, challenges, and solutions relating to the multifaceted aspects of this field. New multimedia standards (for example, MPEG-21) facilitate the seamless integration of multiple modalities into interoperable multimedia frameworks, transforming the way people work and interact with multimedia data. These key technologies and multimedia solutions interact and collaborate with each other in increasingly effective ways, contributing to the multimedia revolution and having a significant impact across a wide spectrum of consumer, business, healthcare, education, and governmental domains.

  9. Exploiting Multimedia in Creating and Analysing Multimedia Web Archives

    Directory of Open Access Journals (Sweden)

    Jonathon S. Hare

    2014-04-01

    Full Text Available The data contained on the web and the social web are inherently multimedia and consist of a mixture of textual, visual and audio modalities. Community memories embodied on the web and social web contain a rich mixture of data from these modalities. In many ways, the web is the greatest resource ever created by human-kind. However, due to the dynamic and distributed nature of the web, its content changes, appears and disappears on a daily basis. Web archiving provides a way of capturing snapshots of (parts of the web for preservation and future analysis. This paper provides an overview of techniques we have developed within the context of the EU funded ARCOMEM (ARchiving COmmunity MEMories project to allow multimedia web content to be leveraged during the archival process and for post-archival analysis. Through a set of use cases, we explore several practical applications of multimedia analytics within the realm of web archiving, web archive analysis and multimedia data on the web in general.

  10. DRMR:Dynamic-Ring-Based Multicast Routing Protocol for Ad Hoc Networks

    Institute of Scientific and Technical Information of China (English)

    Yuan Zhoux; Guang-Sheng Li; Yong-Zhao Zhan; Qi-Rong Mao; Yi-Bin Hou

    2004-01-01

    Recently a number of multicast routing protocols for ad hoc networks have been proposed, however, most of them do not provide proper tradeoffs between effectiveness, efficiency and scalability. In this paper, a novel multicast routing protocol is presented for ad hoc networks. The protocol, termed as dynamic-ring-based multicast routing protocol (DRMR), uses the concept of dynamic ring whose radius can be adjusted dynamically and DRMR configures this type of ring for all group member nodes. According to the principle of zone routing, two nodes whose rings overlap can create route to each other, thus, when the ring graph composed of all rings is connected, each member node has one or more routes to others. DRMR uses the method of expanding ring search (ERS) to maintain the connected ring graph, and also can decrease the radius of the ring to reduce the overhead. The performances of DRMR were simulated and evaluated with NS2, and results show that DRMR has a high data packet delivery ratio, low control overhead and good scalability.

  11. Joint NC-ARQ and AMC for QoS-Guaranteed Mobile Multicast

    Directory of Open Access Journals (Sweden)

    Schwefel Hans-Peter

    2010-01-01

    Full Text Available In mobile multicast transmissions, the receiver with the worst instantaneous channel condition limits the transmission data rate under the desired Quality-of-Service (QoS constraints. If Automatic Repeat reQuest (ARQ schemes are applied, the selection of Adaptive Modulation and Coding (AMC mode will not necessarily be limited by the worst channel anymore, and improved spectral efficiency may be obtained in the efficiency-reliability tradeoff. In this paper, we first propose a Network-Coding-based ARQ (NC-ARQ scheme in its optimal form and suboptimal form (denoted as Opt-ARQ and SubOpt-ARQ, resp. to solve the scalability problem of applying ARQ in multicast. Then we propose two joint NC-ARQ-AMC schemes, namely, the Average PER-based AMC (AvgPER-AMC with Opt-ARQ and AvgPER-AMC with SubOpt-ARQ in a cross-layer design framework to maximize the average spectral efficiency per receiver under specific QoS constraints. The performance is analyzed under Rayleigh fading channels for different group sizes, and numerical results show that significant gains in spectral efficiency can be achieved with the proposed joint NC-ARQ-AMC schemes compared with the existing multicast ARQ and/or AMC schemes.

  12. Energy Optimization for Wireless Sensor Networks using a Novel Dynamic Multicast Routing Protocol

    Directory of Open Access Journals (Sweden)

    S. Sundar Raj

    2014-07-01

    Full Text Available Minimization of energy consumption has always been the predominant factor deciding the acceptability of a routing protocol for wireless ad-hoc networks. In this study we have proposed a novel efficient multicast routing protocols in wireless mobile ad hoc networks is proposed. Due to the high mobility of nodes and highly dynamic topology, performing efficient and robust multicast in a Mobile Ad hoc Network (MANET is a challenging task. Most of existing multicast protocols in MANETs discover the routing path by flooding message over the whole network, which result in considerable cost for routing discovery and maintenance. Moreover, the reliability of the discovered path cannot be guaranteed, since the stabilities of nodes along such path are unpredictable. Here an attempt is made to devise an algorithm combining the features of both energy efficient and low latency algorithms. The new algorithm is intended to do well in real-world scenarios where the energy capacities of the nodes are not uniform. It employs a mobility prediction based election process to construct a reliable backbone structure performing packet transmission, message flooding, routing discovery and maintenance. Several virtual architectures are used in the protocol without need of maintaining state information for more robust and scalable membership management and packet forwarding in the presence of high network dynamics due to unstable wireless channels and node movements.

  13. A New Solution of Multicast Packets Management for Managed Ethernet Switch

    Directory of Open Access Journals (Sweden)

    Sheng LU

    2012-12-01

    Full Text Available This paper has a discussion on the new solution of IGMP management for multicast message in industrial Ethernet. It proposed a new mechanism to minimize the congestion which is based on the taking an adaptive decision during transferring multicast messages. Proposed approach is that a device requesting to start and stop the reception of the multicast streams is accomplished through IGMP join and Leave message requests. Quality of Service (QOS as a component is supported by the Switch Manager as well as features built into the micro chip. The IGMP Snooping component monitors (snoops these join and leave messages to allow it to know which streams to prune from which ports. it is a service provided by most managed Ethernet switches. However, the ICIE (Intelligent Controller for Industrial Ethernet does not provide this capability and requires that another device in the network supports the querier functionality. It is through the external devices solicitation of join messages that allow the IGMP Snooping component to correctly decipher on which ports the downstream listeners are connected.

  14. Pemanfaatan Multimedia sebagai Media Penyuluhan Kesehatan Gigi

    Directory of Open Access Journals (Sweden)

    Hestieyonini Hadnyawati

    2015-10-01

    Full Text Available The effort of suppression promotion and preventive as practice principles of "paradigma sehat" are concept which announcement by Departemen Kesehatan Republik Indonesia in framework reach Indonesia Sehat 2010. This effort as well as possible to get done by everyone Indonesia peoples, with the holistic through way dental education. For this application dental education needed medium. Multimedia are application various medium which different for associate and serve information in form text, audio, chart, animation, and video. Multimedia find occupy somebody for keep 90% what he read, hear, se, mention and done. Using multimedia as dental education medium can be used CD/VCD multimedia module, multimedia presentation, and multimedia web. With this reminder, so using multimedia technology find service as alternative medium for public dental education.

  15. A Survey on Web Multimedia Mining

    CERN Document Server

    Kamde, Pravin M

    2011-01-01

    Modern developments in digital media technologies has made transmitting and storing large amounts of multi/rich media data (e.g. text, images, music, video and their combination) more feasible and affordable than ever before. However, the state of the art techniques to process, mining and manage those rich media are still in their infancy. Advances developments in multimedia acquisition and storage technology the rapid progress has led to the fast growing incredible amount of data stored in databases. Useful information to users can be revealed if these multimedia files are analyzed. Multimedia mining deals with the extraction of implicit knowledge, multimedia data relationships, or other patterns not explicitly stored in multimedia files. Also in retrieval, indexing and classification of multimedia data with efficient information fusion of the different modalities is essential for the system's overall performance. The purpose of this paper is to provide a systematic overview of multimedia mining. This articl...

  16. Flow Control for Multicast: A Weighted Cost-Benefit Approach%针对组播的流量控制:带权的代价-收益法

    Institute of Scientific and Technical Information of China (English)

    何炎祥; 吕慧; 李旭晖; 杜卓敏; 王策

    2003-01-01

    This paper presents a weighted cost-benefit approach based on multicast. Grounded on overlay networkmodel, its principal idea is to construct cost function and benefit function. When estimated benefit is more than cost,multicast request is accepted. This paper demonstrates its application in packet-switched networks and points out itsmerits and shortcomings.

  17. One-to-six WDM multicasting of DPSK signals based on dual-pump four-wave mixing in a silicon waveguide

    DEFF Research Database (Denmark)

    Pu, Minhao; Hu, Hao; Ji, Hua

    2011-01-01

    We present WDM multicasting based on dual-pump four-wave mixing in a 3-mm long dispersion engineered silicon waveguide. One-to-six phase-preserving WDM multicasting of 10-Gb/s differential phase-shiftkeying (DPSK) data is experimentally demonstrated with bit-error rate measurements. All the six...

  18. Broadcast design in cognitive radio ad hoc networks

    CERN Document Server

    Song, Yi

    2014-01-01

    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

  19. Hypervideos and interactive multimedia presentations

    NARCIS (Netherlands)

    B. Meixner (Britta)

    2017-01-01

    textabstractHypervideos and interactive multimedia presentations allow the creation of fully interactive and enriched video. It is possible to organize video scenes in a nonlinear way. Additional information can be added to the video ranging from short descriptions to images and more videos.

  20. Emotional Design in Multimedia Learning

    Science.gov (United States)

    Um, Eunjoon; Plass, Jan L.; Hayward, Elizabeth O.; Homer, Bruce D.

    2012-01-01

    Can multimedia learning environments be designed to foster positive emotions that will improve learning and related affective outcomes? College students (N = 118) were randomly assigned to 4 conditions created by 2 factors related to learners' emotion: "external mood induction" (positive vs. neutral emotions) and "emotional design induction"…