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multicast Protocol for Uni-Directional Networks

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Journal of Computer Science & Technology 2000年第2期15卷 158-168页

作者：黄皓陈贵海谢立孙钟秀 State Key Laboratory for Novel Software Technology Department of Computer Science and Technology Nanjing University Nanjing P.R. China

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.

关键词： routing protocol multicast unicast uni-directional network

multicast resource allocation with min-rate requirements in OFDM systems

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The Journal of China Universities of Posts and Telecommunications 2010年第3期17卷 24-30,51页

作者： XU Wen-jun HE Zhi-qiang NIU Kai LIN Jia-ru WU Wei-ling School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing 100876 China

This article addresses the multicast resource allocation problem with min-rate requirement constraints in orthogonal frequency division multiplexing （OFDM） systems. Due to the prohibitively high complexity for nonlinear and combinatorial optimization, the original problem is relaxed and reformulated to form a standard optimization problem. By theoretical derivation according to the Karush-Kuhn-Tucker （KKT） conditions, two propositions are presented as the necessary criteria for optimality. Furthermore, a two-step resource allocation scheme, including subcarrier assignment and power allocation, is proposed on a basis of the propositions for practical implementation. With the rain-rate based multicast group order, subcarriers are assigned in a greedy fashion to maximize the capacity. When subcarrier assignment is determined, the proposed power allocation can achieve the optimal performance for the rain-rate constrained capacity maximization with an acceptable complexity. Simulation results indicate that the proposed scheme approximates to optimal resource allocation obtained by exhaustive search with a negligible capacity gap, and considerably outperforms equal power distribution. Meanwhile, multicast is remarkably beneficial to resource utilization in OFDM systems.

关键词： OFDM multicast resource allocation min-rate requirements

Robust load-balanced backbone-based multicast routing in mobile opportunistic networks

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Frontiers of Computer Science 2023年第4期17卷 109-125页

作者： Di ZHANG Dong ZHAO uadong MA Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and TelecommunicationsBeijing 100876China

Mobile opportunistic network(MON)is an efficient way of communication when there is no persistent connection between nodes.multicast in MONs can be used to efficiently deliver messages to multiple destination nodes.However,because multiple destination nodes are involved,multicast routing is more complex than unicast and brings a higher communication cost.Backbone-based routing can effectively reduce the network overhead and the complexity of routing scheme.However,the load of backbone nodes is larger than that of regular nodes.If the backbone node’s buffer is exhausted,it will have a significant impact on the performance of the routing scheme.Load balancing can improve the ability of backbone to deal with the change of network load,and backbone maintenance algorithm can provide backbone robustness.In this paper,we propose a robust load-balanced backbone-based multicast routing scheme in MONs.In the backbone construction algorithm,we transform the problem of backbone construction into a multi-objective optimization problem,and propose a multi-objective evolutionary algorithmbased backbone construction algorithm,namely LBMBCMOEA algorithm.In addition,in order to increase the robustness of the backbone-based routing scheme,we propose a localized multicast backbone maintenance algorithm(MBMA)to deal with the buffer exhaustion of backbone nodes.When a backbone node’s residual buffer is insufficient,MBMA algorithm selects other nodes to replace the backbone node.The results on extensive simulations show that when considering the node buffer size constraints,compared with previous backbone-based multicast routing schemes,our proposed algorithm has better performance,and when the node’s residual buffer is insufficient,MBMA algorithm can significantly improve the performance of the backbone-based multicast routing scheme.

关键词： mobile opportunistic network multicast multiobjective optimization backbone construction backbone maintenance

An Optimal multicast Algorithm for Cube-Connected Cycles

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Journal of Computer Science & Technology 2000年第6期15卷 572-583页

作者：宋建平侯紫峰史云涛 Institute of Computing Technology Chinese Academy of Sciences Beijing P.R. China

This paper presents an efficient algorithm that implements one to-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 - 1 destinations 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.

关键词： multicast cube-connected cycle wormhole routing dimensionordered routing one-port architecture

Increasing multicast transmission rate with localized multipath in software-defined networks

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Frontiers of Computer Science 2019年第2期13卷 413-425页

作者： Siyuan TANG Bei HUA School of Computer Science and Technology University of Science and Technology of China (USTC) Hefei 230027 China Suzhou Institute for Advanced Study USTC Suzhou 215123 China

Network layer multicast is a highly efficient oneto ?many transmission mode. Data rates supported by different group members may differ if these members are located in different network environments. Currently there are roughly two types of methods solving the problem, one is limiting the data rate so that every group member can sustain transmissions, and the other is building multiple trees to increase the provision of network bandwidth. The former is inefficient in bandwidth usage, and the latter adds too many states in the network, which is a serious problem in Software-Defined Networks. In this paper, we propose to build localized extra path(s) for each bottleneck link in the tree. By providing extra bandwidth to reinforce the bottleneck links, the overall data rate is increased. As extra paths are only built in small areas around the bottleneck links, the number of states added in the network is restrained to be as small as possible. Experiments on Mimnet verify the effectiveness of our solution.

关键词： software-defined networking network layer multicast localized multipath

A Cluster-Based Opportunistic multicast in Multi-hop Wireless Networks

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Chinese Journal of Electronics 2015年第1期24卷 170-175页

作者： ZHANG Haiyang Beijing Key Laboratory of Intelligent Telecommunications Software and Multimedia Beijing University of Posts and Telecommunications

multicast has become increasingly important in multi-hop wireless networks for such applications which deliver shared media and data to multiple receivers.However, the existing multicast protocols for wireless network have large control overhead, and cannot adequately take the advantage of broadcast communication mode in multicast structure for sharing the forwarding path. This paper proposes a Cluster-based opportunistic multicast(COM) algorithm, which constructs multicast tree structure based on clusters by utilizing a stability greedy algorithm to achieve the minimum total Cluster-based expected transmission count(CETX). In this multicast tree structure, the edge is created between the kernel sets respectively belonging to two clusters for improving the forwarding efficiency and the stability of this structure. In the process of data distribution, our multi-layer solution combines multicast and opportunistic routing to improve the efficiency of transmission. Simulation results show that COM scheme can achieve the less total number of sending packets, and higher stability than other topology-based solutions and opportunistic multicast.

关键词： Multi-hop wireless network multicast Opportunistic routing Cluster.

A video conferencing system based on SDN-enabled SVC multicast

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Frontiers of Information Technology & Electronic Engineering 2016年第7期17卷 672-681页

作者： En-zhong YANG Lin-kai ZHANG Zhen YAO Jian YANG School of Information Science and Technology University of Science and Technology of China

Current typical video conferencing connection is bridged by a multipoint control unit(MCU),which may cause large delay and communication bottleneck for the whole system.With the development of network technology,a video conferencing system can be implemented based on software-defined networking(SDN),which makes the service controllable and improves the scalability and flexibility.Additionally,a video encoding method called scalable video coding(SVC) can also help.In this paper,we propose a video conferencing architecture based on SDN-enabled SVC multicasting,which discards the traditional Internet group management protocol(IGMP) and MCU.The system implements SVC multicast streaming to satisfy different device capabilities of various conference terminals.The SDN controller is responsible for dynamically managing and controlling the layers of a video stream when a conference member faces network congestion.Also,a conference manager is designed to facilitate the management of the conference members.Experimental results show that our system can not only provide a flexible and controllable video delivery,but also reduce the network usage while guaranteeing the quality of service(QoS) of video conferencing.

关键词： Software-defined networking(SDN) multicast Scalable video coding Video conferencing system

Fuzzy mathematics and game theory based D2D multicast network construction

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Journal of Systems Engineering and Electronics 2019年第1期30卷 13-21页

作者： LI Zhuoming CHEN Xing ZHANG Yu WANG Peng QIANG Wei LIU Ningqing School of Electronics and Information Engineering Harbin Institute of Technology School of Computer Science and Technology Harbin Institute of Technology

Device to device(D2 D) multi-hop communication in multicast networks solves the contradiction between high speed requirements and limited bandwidth in regional data sharing communication services. However, most networking models demand a large control overhead in eNodeB. Moreover, the topology should be calculated again due to the mobility of terminals, which causes the long delay. In this work, we model multicast network construction in D2 D communication through a fuzzy mathematics and game theory based algorithm. In resource allocation, we assume that user equipment(UE) can detect the available frequency and the fuzzy mathematics is introduced to describe an uncertain relationship between the resource and UE distributedly, which diminishes the time delay. For forming structure, a distributed myopic best response dynamics formation algorithm derived from a novel concept from the coalitional game theory is proposed, in which every UE can self-organize into stable structure without the control from eNodeB to improve its utilities in terms of rate and bit error rate(BER) while accounting for a link maintenance cost, and adapt this topology to environmental changes such as mobility while converging to a Nash equilibrium fast. Simulation results show that the proposed architecture converges to a tree network quickly and presents significant gains in terms of average rate utility reaching up to 50% compared to the star topology where all of the UE is directly connected to eNodeB.

关键词： device to device (D2D) communication multicast network fuzzy logic game theory tree architecture

A Novel Tree-Based Genetic Algorithm for the multicast Protocol in Two-Tiered WSNs

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Chinese Journal of Electronics 2020年第5期29卷 852-858页

作者： ZHANG Qiongbing XIE Chengwang JIANG Lei School of Computer Science and Engineering Hunan University of Science and Technology School of Computer and Information Engineering Nanning Normal University

Genetic algorithms(GAs) serve as a class of powerful tools to search for an effective multicast routing scheme among multiple cluster header nodes,which strongly affects the lifetime of two-tiered Wireless sensor networks(WSNs). This paper proposes a novel Genetic algorithm(GA) with a new crossover mechanism called Leaf crossover for the multicast routing among upper tier nodes in two-tiered WSNs, which outperforms the existing popular tree-based GAs by not requiring the global network link information, encoding/decoding or repair operations. Our simulation study indicates that the proposed algorithm could prolong the lifetime of multicast service, increase the packet delivery ratio as well as converge fast by comparison with existing GAs.

关键词： Wireless sensor networks (WSNs) multicast Genetic algorithm (GA) Leaf crossover