基于代理的QoS组播路由算法

提出了一种基于代理（Agent)的QoS组播路由算法,它根据一个在网络中漫游的移动代理收集的网络状态来建立保证QoS的组播树,仿真实验表明,该算法是有效的和可行的。     

网络拓扑结构对IP组播效率影响的研究

研究了不同网络拓扑结构对IP组播效率的影响,给出了一种度量组播效率的方法,并进行了分析与仿真.结果表明:在随机选择组播树根节点的情况下,平均节点度越大的网络,组播效率越低;限制组播路由的通过性和适当选择组播根节点的位置能够有效提高组播效率;有源最短路径树在不同网络拓扑下的性能差异较大,并且不是一种能够适合于各种网络结构的高效组播树构建算法.     

基于IGMP协议的移动安全移动组播访问控制方案

结合现有的不同移动组播访问控制方案的优点，给出了一个基于IGMP协议的移动安全移动组播访问控制方案。该方案由边缘路由器（Edge Router，ER）和移动组播管理中心（Mobile Multieast Manager，MMM）组成。边缘路由器拦截用户申请加入移动组播组的IGMP请求报文，转发给移动组播管理中心；移动组播管理中心根据定义的访问策略处理请求，返回决策信息；边缘路由器根据移动组播管理中心的决策信息处理相应的请求，决定是否允许用户加入移动组播组，从而实现移动组播访问控制机制。     

基于神经网络的组播路由调度方法

针对在高速包交换计算机网络中端到端时延及时延抖动限制的组播路由问题，提出了基于Ｈｏｐｆｉｅｌｄ神经网络的组播路由优化算法。实验表明，本算法能根据组播应用对时延及时延抖动限制的要求，快速，有效地构造最优组播树，有较强的实时性。     

浅议IP组播技术在视频中的应用

IP组播技术实现IP网络中点到多点的高效数据传送。因为组播能够有效地节约网络带宽、降低网络负载,所以在实时数据传送、多媒体会议、数据拷贝、游戏和仿真等诸多方面都有广泛的应用。介绍组播的基本概念、组播地址的分配以及目前通用的组播协议;流媒体的基本概念、流媒体系统的组成;并结合大学的校园网,利用IP组播实现现场直播。     

CISCO路由器中PIM-SM的改进——Mul-Any(Multicast与Anycast结合)

在宽带网络的建设和运营中,组播业务作为未来最具潜力的业务之一,得到前所未有的重视。针对PIM-SM的缺陷进行改进,将Multicast(组播)与Anycast(任播)两种传输方式结合(Mul-Any),通过对多组实验数据进行分析得出结论。     

VPN技术在IP组播视频会议系统中的应用

 针对IP组播视频会议系统在共网上部署应用时出现的安全性差、费用高、IP组播路由器资源有限等问题,提出在Internet上应用VPN技术来实现IP组播视频会议系统的解决方案,并介绍了系统的VPN网络结构和实施方法.同时,还对VPN技术的基本概念、关键技术及其特点和IP组播视频会议系统的总体设计作了简单阐述.最后在广域网上对该会议系统进行了测试.测试结果表明,实现了在广域网上运行IP组播会议系统,并有效地保证会议数据传输的安全性和可靠性.     

网络视频传输中基于IP组播技术的数据库响应速度研究

IP组播是一项旨在节省带宽的技术，通过向数千个用户同步传送一个单独的数据流降低网络流量。组播数据包在网上的某个节点被路由器进行复制，然后根据组播协议进行发送路径的选择。本文分析了网络视频传输过程中远程数据库的响应时间问题，提出了有效的解决方案，从而这种时间上的延迟可以及时的进行实时调整。     

对等网络技术在网络电视(IPTV)中的应用研究

本文为解决网络电视（IPTV）网络中数据服务器传输瓶颈问题,提出了一种新方法,即引入对等网络技术。文中介绍了对等网络技术原理,将对等网络技术与组播技术进行了比较,研究了对等网络在IPTV应用中的实现方法,总结出对等网络技术的优势,并提出对等网络存在的不足,以及采用DRM技术来弥补不足的方法。     

IP组播路由协议的研究与实现

概述了组播路由协议，分析了协议独立的组播路由－稀疏模式（PIM－SM）的缺陷，提出多个会聚点（RPs)的PIM－SM的改进机制，多个RPs机制有效地提高了原有单个RP的PIM－SM协议的健壮性，有利于实现负载均衡、分类业务及提高系统的容错性能，并讨论多个RPs机制的开销问题。分析了PIM－SM实现细节和组播技术的前景。     

Ant Colony Optimization for Multi-Objective Multicast Routing

In the distributed networks, many applications send information from a source node to multiple destination nodes. To support these applications requirements, the paper presents a multi-objective algorithm based on ant colonies to construct a multicast tree for data transmission in a computer network. The proposed algorithm simultaneously optimizes total weight (cost, delay and hop) of the multicast tree. Experimental results prove the proposed algorithm outperforms a recently published Multi-objective Multicast Algorithm specially designed for solving the multicast routing problem. Also, it is able to find a better solution with fast convergence speed and high reliability.     

Generation of Low-Delay and High-Stability Multicast Tree

Delay and stability are two key factors that affect the performance of multicast data transmission in a network. However, current algorithms of tree generation hardly meet the requirements of low delay and high stability simultaneously. Given a general network, the generation algorithm of a multicast tree with minimum delay and maximum stability is an NP-hard problem, without a precise and efficient algorithm. To address these challenges, this paper studies the generation of low-delay and high-stability multicast trees under the model of spanning tree based on stability probability, degree-constrained, edge-weighted for multicast (T-SDE). A class of algorithms was proposed which creates the multicast tree greedy on the ratio of fan-out to delay (RFD) and probability of stability of terminal to obtain a high performance in multicast. The proposed algorithms greedily select terminals with a large RFD and a high probability of stability as forwarding nodes in the generation of the multicast tree, where the larger RFD and higher stability of upstream nodes are beneficial to achieve a low transmission delay and high stability in multicast. The proposed RFD can be compatible with the original model, which can take advantage of network connectivity during the generation of a multicast tree. This paper carries out simulation experiments on Matlab R2016b to measure the performance of the proposed algorithm. Experimental results show that the proposed algorithm can provide a smaller height, higher stability, and a lower transmission delay of the resulting multicast tree than other solutions. The spanning tree of the proposed algorithms can support low transmission delay and high stability in multicast transmission.     

Distributed multicast routing algorithm with dynamic performance in multimedia networks

The delay and delay variation-bounded multicast tree (DVBMT) problem is known to be NP-complete. In this paper, we propose an efficient distributed dynamic multicast routing algorithm to produce routing trees with delay and delay variation constraints. The proposed algorithm is fully distributed, and supports the dynamic reorganizing of the multicast tree in response to changes for the destination. Simulations demonstrate that our algorithm is better in terms of tree delay and routing 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.     

一种基于多播路由图的最小子树图搜索算法

提出了一种基于网络编码的新的多播路由算法,该算法在搜索信源节点到各接收者路径族的过程中,考虑了不同路径族之间链路的共享,以降低带宽资源消耗,提高网络性能.基于得到的多播路由图,提出了一种最小子树图搜索算法,并利用最小子树图的性质,对相应于多播路由图的子树图进行化简.最后,在最小子树图上进行有效的网络编码,所有的网络编码问题可以简化为搜索多播网络的最小子树图问题.     

面向多媒体流的主动分层多播拥塞控制方案

针对现有分层多播拥塞控制方案存在较大的拥塞响应延时,吞吐率抖动剧烈,和不满足TCP友好的问题,给出了一个主动分层多播服务模型,通过引入主动标记分层、可用带宽主动测量以及优先级分层过滤机制,提出了一种新的面向多媒体流的自适应主动分层多播拥塞控制方案AALM。仿真结果表明,该方案能够有效地改进分层多播拥塞控制的性能,具有较快的拥塞响应速度、较好的稳定性和TCP友好特性。     

NS-2的SSM协议仿真扩展研究

对SSM实现中的关键技术进行了研究,在此基础上分析了基于NS-2的IP组播模拟器的结构与原理.通过对NS-2中的IP组播路由仿真模块结构的修改,实现对SSM协议的仿真扩展.     

Dynamic multicast routing and wavelength assignment using generic graph model for wavelength-division-multiplexing networks

The problem of dynamic multicast routing and wavelength assignment (MC-RWA) in the wavelength-routed wavelength-division-multiplexing networks is addressed. Current solutions to this problem always rely on homogeneous network constructions. However, future backbone networks tend to be heterogeneous in nature. Thus, the dynamic MC-RWA problem should be studied in a more realistic situation by considering the heterogeneity of network structures. A new graph model is proposed for the MC-RWA problem. This model is based on layered auxiliary graph which is generic and able to support various node architectures and heterogeneous network structures. Based on this graph model, the dynamic MC-RWA problem can be simply solved by an efficient multicast tree algorithm on various light-splitting and wavelength-conversion scenarios. In general, this graph model provides a universal platform to study different aspects of the dynamic MC-RWA as well as related problems.