提出一种面向物联网应用的基于消息内容和订阅条件的路由算法,采用基于多级索引的模型构建了订阅树,有效地减少了不必要的消息过滤和消息转发数量,提高了条件匹配的效率.算法根据过滤器之间的覆盖关系以及各节点间的网络连通状况,构建了消息分发树,使得消息能够选择一条最佳的转发路径,保证了链路代价最小.同时,针对网络的动态变化,设计了消息分发树的调整和路由表的维护策略,以确保准确路由.实验结果表明算法是有效的,性能优于现有方法.同时,在减少不必要的消息过滤,均衡节点负载方面有良好的效果.
We propose a routing algorithm based on message content and subscription requirements for WInternet pipe communication protocol. First of all,a filter model based on a multilevel index structure is presented. It effectively reduces numbers of message filtering and forw arding,and improves the matching efficiency of subscription requirements. Secondly,the content-based routing algorithm takes advantage of covering relations and link status among nodes to build a message distribution tree. It ensures that messages can be forw arded along an optimal path,so that the link cost can be minimal. M eanw hile,considering the dynamic changes in the netw ork,w e design strategies of adjusting the message distribution tree and maintaining the routing table,to ensure accurate routing. Experimental results show that the algorithm is effective and outperforms state-of-the-art methods. M eanw hile,it can reduce the number of messages to be filtered and keep good load balance among netw ork nodes.