内容发布订阅系统路由算法和自配置策略研究

路由算法和动态自配置特性是实现大规模基于内容的发布订阅系统的两个关键问题.尽管已经有多种路由算法被提了出来,但是它们没有充分利用组播技术提高系统性能和节省网络带宽;此外,已有系统的网络都是静态的,不能够进行网络的自动配置.首先,提出了具有组播集群的层次性系统模型,设计了混合式路由算法,充分利用物理网络组播的特性,节省网络带宽.然后,提出了组播集群复制协议和基于内容的组播树协议CMTP,分别处理节点或者链路失效导致的网络分割以及路由的重建.实验结果表明,这些算法和协议的引入节省了网络带宽,显著提高了系统的性能,保证了系统的自配置特性.

Research on Routing Algorithm and Self-Configuration in Content-Based Publish-Subscribe System

Content-Based publish/subscribe systems have recently received an increasing attention. Efficient routing algorithms and self-configuration are two key issues in the area of large-scale content-based publish/subscribe systems. Although many routing algorithms have been proposed, none of them fully exploits multicast to enhance system performance and save network bandwidth. In addition, the vast majority of currently available publish-subscribe middleware has ignored this self-configuration problem. This paper first proposes a hierarchical system model with multicast clustering. Then a hybrid routing algorithm is presented, which can fully exploit multicast in order to reduce the used network bandwidth. Moreover, a multicast clustering replication protocol and a content-based multicast tree protocol are presented for coping with the node or link failures and rebuilding the event dispatcher trees. Experimental results reveal that the system has better routing efficiency and lower cost, and guarantees the self-configuration characteristic.