文档介绍：南京邮电大学
硕士学位论文
遗传算法在QoS多播路由算法中的应用
姓名:姜华
申请学位级别:硕士
专业:信号与信息处理
指导教师:李晓飞
2011-03
南京邮电大学硕士研究生学位论文摘要
摘要
在计算机网络中,多播是指从源节点将同一份信息传送到多个目的节点(不一定是网
络中所有节点)的技术。多播路由是网络层具备的功能,多播问题的关键在于多播路径的
确定。实现多播的一般方式是建立多播树,多播树是根为源节点,且覆盖所有多播成员的
一颗生成树。多播树的优点在于:首先,信息以并行方式沿着树枝发送到不同的多播终点,
从而降低了信息传递的时延;其次,信息的复制只在树的分支处进行,因此网络中需要传
送的复制信息量最少,能够节约网络带宽资源,降低网络负载,减少拥塞,所以多播成为
目前研究最多、应用最广的网络信息传输方式。多播路由算法主要用来建立一颗性能良好
的多播树,并使它能够满足各种业务的服务质量需求。
本论文研究如何将遗传算法这一新型优化算法应用到时延约束 QoS 多播路由算法中,
利用该算法的并行搜索、种群优化的特点,为解决 QoS 多播路由问题寻找新的途径。论文
提出了一种改进的 Dijkstra 算法和一种基于遗传算法的时延约束多播路由算法,并对本文
提出的算法进行了收敛性分析和仿真验证。本文算法对解决时延受限多播路由问题有一定
改进,尤其在网络规模较大的情况下,可选路径较多时,本文算法搜索速度快,可大大减
小路由计算时间,能够满足多媒体网络实时性的要求。
关键字:多播;多播树;多播路由算法;QoS;遗传算法
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南京邮电大学硕士研究生学位论文 Abstract
Abstract
works, multicast routing is nerwork-layer functions that constructs paths,
along which the same message from source node can be sent to multiple destination nodes, and
the key of multicast problem lies in the determination of multicast paths. The general way to
realize multicast is to establish multicast tree, which is a spanning tree that take the root as
source node and share many links in transmitting the message to the desination set. The multicast
tree has two advantages. At first, the message is transmitted to different multicast membership by
parallel mode, thus decreasing the delay of message transmission. The second, the message only
need to be replicated at forking nodes, so it saves the bandwidth, and optimizes work
performance. Multicast routing algorithms are used pute multicast trees of good
performance that satisfy QoS requirements for all kinds of business.
This paper examines how this new optimization algorithm of ic algorithm applied to
the delay constrained QoS multicast routing algorithm, A new approach to resolve QoS multicast
routing problem has been provided through parallel search and group improvement of the
paper emphasizes an improved algorithm of the Dijkstra algorithm and the delay
c