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Achieving inter-session fairness for layered video multicast 总被引:1,自引:0,他引:1
Wei Kuang Lai Chieh Ying Pan 《Broadcasting, IEEE Transactions on》2002,48(3):215-222
The Internet is increasingly used to deliver multimedia services. Since there are heterogeneous receivers and changing network conditions, it has been proposed to use adaptive rate control techniques such as layered video multicast to adjust the video traffic according to the available Internet resources. A problem of layered video multicast is that it is unable to provide fair bandwidth sharing between competing video sessions. We propose two schemes, layered video multicast with congestion sensitivity and adaptive join-timer (LVMCA) and layered video multicast with priority dropping (LVMPD), to achieve inter-session fairness for layered video multicast. Receiver-driven layered multicast (RLM), layer-based congestion sensitivity, LVMCA, and LVMPD are simulated and compared. Results show both proposed schemes, especially LVMPD, are fairer and have shorter convergence time than the other two schemes. 相似文献
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组播技术对Internet发展至关重要,它以高效、可扩展的方式发送单点到多点、多点到多点数据,很多专家认为它必然成为下一代互联网的关键技术之一。现就其中组播路由协议对网络性能的影响进行了研究。 相似文献
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在overlay网络上的负载平衡多播路由算法 总被引:1,自引:0,他引:1
针对基于代理服务器的overlay网络的负载平衡多播路由算法被提出.它能均衡利用overlay网络的有限资源,并能满足多播应用的延迟限制需求.首先用具有延迟约束的Steiner树问题对路由问题进行建模;然后采用预计算方法将计算复杂度集中在预备的单点路径计算上,使由这些单点路径所构成的网络更易于构建负载平衡路由树:预计算只计算一次,结果使用多次,因此降低了总体的计算复杂度.仿真实验的结果表明,相对于其他的快速启发式算法,该算法能提供更为优越的性能.整体而言,基于预计算的负载平衡多播路由算法在性能和计算复杂度方面取得了很好的平衡. 相似文献
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《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1983,71(12):1435-1441
The practical experiences encountered in an early application of the ISO/OSI Reference Model are discussed. The embedding of a new LAN within an existing military communication system is analyzed in accordance with the ISO/OSI Model. The functional layering of the existing system is identified to aid in resolving layering issues of the new network. Structured analysis techniques are applied to organize both connection-oriented and cocrectionless functions of the new network into appropriate layers and define layer interfaces. Some concepts to organize layer management are presented. 相似文献
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Adams A. Tian Bu Friedman T. Horowitz J. Towsley D. Caceres R. Duffield N. Presti F.L. Moon S.B. Paxson V. 《Communications Magazine, IEEE》2000,38(5):152-159
We present a novel methodology for identifying internal network performance characteristics based on end-to-end multicast measurements. The methodology, solidly grounded on statistical estimation theory, can be used to characterize the internal loss and delay behavior of a network. Measurements on the MBone have been used to validate the approach in the case of losses. Extensive simulation experiments provide further validation of the approach, not only for losses, but also for delays. We also describe our strategy for deploying the methodology on the Internet. This includes the continued development of the National Internet Measurement Infrastructure to support RTP-based end-to-end multicast measurements and the development of software tools to analyze the traces. Once complete, this combined software/hardware infrastructure will provide a service for understanding and forecasting the performance of the Internet 相似文献
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Active network support for multicast applications 总被引:1,自引:0,他引:1
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We consider cooperative data multicast in a wireless network with the objective to maximize the network lifetime. We present the maximum lifetime accumulative broadcast (MLAB) algorithm that specifies the nodes' order of transmission and transmit power levels. We prove that the solution found by MLAB is optimal but not necessarily unique. The power levels found by the algorithm ensure that the lifetimes of the active relays are the same, causing them to fail simultaneously. For the same battery levels at all the nodes, the optimum transmit powers become the same. The simplicity of the solution is made possible by allowing the nodes that are out of the transmission range of a transmitter to collect the energy of unreliably received overheard signals. As a message is forwarded through the network, nodes will have multiple opportunities to reliably receive the message by collecting energy during each retransmission. We refer to this cooperative strategy as accumulative multicast. Cooperative multicast not only increases the multicast energy-efficiency by allowing for more energy radiated in the network to be collected, but also facilitates load balancing by relaxing the constraint that a relay has to transmit with power sufficient to reach its most disadvantaged child. When the message is to be delivered to all network nodes this cooperative strategy becomes accumulative broadcast (Maric and Yates, 2002). Simulation results demonstrate that cooperative broadcast significantly increased network lifetime compared with conventional broadcast. We also present the distributed MLAB algorithm for accumulative broadcast that determines the transmit power levels locally at the nodes. 相似文献
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提出一种新的基于网络编码的负载均衡路由量度CRM-LB(coding-aware routing metric with load balancing),CRM-LB在CRM(coding-aware routing metric)的基础上增加了对路径p上所有节点通信密集程度与网络拥塞程度的考虑。进一步提出了基于CRM-LB的无线mesh网络多播路由CLR(coding and load-balancing routing)。该协议可以增加网络编码机会,同时考虑到网络中的负载均衡。通过性能分析和仿真实验表明,该协议在提高多播吞吐量的前提下,不仅能更好地支持网络编码,而且网络负载基本均衡。 相似文献
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主要讨论了基于移动IP网下的组播技术。在给出了基本的两种移动组播机制:即远程签署RS和双向隧道BT的基础上,重点分析了RBMoM协议,即基于范围的移动组播协议,同时比较了三者的优缺点。最后给出RBMoM协议的实现流程图。 相似文献
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Web 2.0 has been becoming the new tendency of the Internet development. In order to get better management of web 2.0 network resource and guarantee of service quality, the architecture and the advantages of web 2.0 over Ajax technology is analyzed, and the impact of Ajax on bandwidth performance of web application is discussed. 相似文献
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CAO Zhen TANG Bi-hua LIU Yuan-an XIE Gang LIU Fang DENG Pan-liang School of Electronic Engineering Beijing University of Posts Telecommunications Beijing China Key Laboratory of Universal Wireless Communication Ministry of Education China 《中国邮电高校学报(英文版)》2011,18(6):59-67,88
In wireless multicast,network coding has recently attracted attentions as a substantial improvement to packet retransmission schemes.However,the problem of finding the optimal network code which minimizes the retransmissions is hard to solve or approximate.This paper presents two schemes to reduce the number of retransmissions for reliable multicast efficiently.One is retransmission using network coding based on improved Vandermonde matrix(VRNC),the other is retransmission using network coding based on adaptive improved Vandermonde matrix(AVRNC).Using VRNC scheme the sender selects the packets all receivers have lost and encodes them with improved Vandermonde matrix;when receivers receive enough encoded retransmission packets,all the lost packets can be recovered.With AVRNC scheme,the sender can obtain the recovery information from all the receivers after sending out per retransmission packet,and then the improved Vandermonde matrix can be updated,thus reducing the complexity of encoding and decoding.Our proposed schemes can achieve the theoretical lower bound assuming retransmission packets lossless,and approach the theoretical lower bound considering retransmission packets loss.Simulation results show that the proposed algorithms can efficiently reduce the number of retransmissions,thus improving transmission efficiency. 相似文献
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在基于光路交换的4节点16×10 Gbps双纤单向新型分布式全光自愈环网上,利用啁啾光纤光栅(CFBG)和环行器等无源器件实现了光层组播,避免了光/电/光转换.CFBG在网络中用于实现色散补偿、上下话路和波长路由.通过调节光栅的中心波长,分别完成对控制信息、组播业务信息的分别读取.整个网络不存在关键性节点,每个节点都可以作为组播业务的发起端和接收端.根据控制信息配置传输信道,提高了组播数据流的传输效率.研究结果表明,这种组播方式具有物理实现简单、安全性高、对组播数据速率和格式透明以及数据传输无阻塞等特点. 相似文献
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在单频网多播传输中,传统的全反馈动态功率分配数算法需要根据每个时隙反馈的用户瞬时信道信息进行实时的调整,所以造成了资源分配频率快、上行反馈开销大的缺点。为了克服这个缺点,提出了一个低复杂度、没有用户反馈的单频网多播开环半动态功率分配算法。首先在各小区等功率分配的假设下,根据单频网的形状信息算出各小区等价信道增益,然后再根据这个增益值,实现满足速率需求情况下的各小区功率分配。仿真结果显示,与全反馈的动态功率分配算法相比,该算法以一小部分性能损失为代价,大大减少了单频网的上行反馈和资源分配的开销,因此更适用于实际的单频网多播系统。 相似文献
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提出了一种通过多播中组管理功能完成移动IP位置管理方法。每一个自治网络中都设置一个移动路由代理(MA),形成一个管理移动节点位置绑定信息的虚拟专用网,通过将与移动主机通信的节点联合起来构成一棵多播树,使网络中各节点相互合作维护移动节点的位置更新。设计了绑定信息表的存储结构和管理移动位置绑定信息的算法。模拟实验表明,提出的基于多播的位置管理方案能够使通信对端实时了解移动节点的转交地址,减少向家乡代理注册的时间和次数,减小了传输延迟,为实时业务传输提供较好的支持。同时减轻了家乡代理和各主机的负担,使移动IP的性能得到优化。 相似文献
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WDM光网络中光层组播技术的研究 总被引:1,自引:0,他引:1
本文分析了光层组播原理。在物理层实现组播 ,使该技术在整个互联网实施实时交互音像通信和有效抑止“电子瓶颈”效应有着重大作用。文中对两种不同结构具有光层组播的OXC进行了分析比较。并且对WDM光网络中的无阻塞组播通信波长满足条件进行了分析探讨。 相似文献
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We present a new algorithm for online routing of bandwidth-guaranteed multicasts where routing requests arrive one by one without any prior knowledge of future requests. A multicast routing request consists of a source, a set of receivers, and a bandwidth requirement. Two multicast applications of interest are routing of point-to-multipoint label-switched paths in multiprotocol label switched (MPLS) networks, and the provision of bandwidth-guaranteed virtual private network (VPN) services under the "hose" service model. Without prior knowledge of multicast requests, offline multicast routing algorithms cannot be used. Online algorithms are needed to handle requests arriving one by one and to satisfy as many potential future demands as possible. Our new online algorithm is based on the idea that a newly routed multicast must follow a route that does not interfere too much with network paths that may be critical to satisfy future demands. We develop a multicast tree selection heuristic based on the idea of deferred loading of certain critical links. The algorithm identifies them as links that, if heavily loaded, would make it impossible to satisfy future demands between certain ingress-egress pairs. The algorithm uses link-state information and some auxiliary capacity information for multicast tree selection and is amenable to distributed implementation. Unlike previous algorithms, our algorithm exploits any available knowledge of the network ingress-egress points of potential future demands, even though the demands themselves are unknown. It performs very well. 相似文献
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Jaecheol Kim Ji Hoon Lee Hojin Lee Taekyoung Kwon Yanghee Choi 《Wireless Communications and Mobile Computing》2012,12(11):999-1012
In wireless network convergence, each mobile host is expected to have multiple kinds of wireless interfaces. Multicast‐based applications are expected to be widely deployed. In this paper, a new network selection scheme is proposed for a mobile host to select the most appropriate wireless access network to maximize user satisfaction and ISP's profit, simultaneously. We have devised a metric to measure a user's satisfaction and we also developed a ‘normalized network resource’ metric for system profit measure. We have compared our scheme with three other reference schemes, through simulations. Depending on the network deployment situations, our scheme exhibits one‐fifth service disruption time of other reference schemes, while the resource consumption of our scheme is comparable to that of the minimum resource scheme. Overall, the gain of our scheme becomes higher as users move faster and/or the population density increases. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献