一种基于混合式双层拓扑的发布/订阅系统

A Publishing/Subscription System Based on the Hybrid Two-Layer Topology

摘要: 基于内容的快速数据分发是分布式环境中资源汇聚和共享的一项关键技术。为更好的满足动态网络环境中对数据分发实时性的要求，提出一种基于混合式双层拓扑的发布/订阅系统，它包含一种基于内容的双层拓扑结构CBDLO，下层是一个非结构化的拓扑结构，上层是多个对应不同属性的分布式平衡二叉树；一种基于内容的带踪迹路由算法CRAWL，以随机行走的方式在下层非结构化拓扑上转发数据，同时为对应数据寻找相应的上层属性拓扑的入口；一种基于属性计数的分布式匹配算法CDM，在上层的分布式平衡二叉树上并行的匹配数据的各个属性，并把匹配的数据发送到对数据感兴趣的节点上。实验结果表明，该系统能够有效支持大规模动态网络中的数据分发，降低分发开销和匹配延迟。

Abstract: Data distribution is a key technology for resources convergence and sharing in distributed environment. To better meet the requirement for data distribution real-time dynamic network environment, we put forward a publishing/subscription system based on the hybrid two-layer topology. It contains a two-layer topology CBDLO based on content; the lower is an unstructured topology structure; the upper is multiple corresponding to different attributes of distributed balanced binary tree; CRAWL forwards the data on the lower unstructured topology in the form of random walk, so that the data can be sent to the corresponding upper topology entry; it also includes a matching algorithm named CDM for the parallel matching data properties on the upper distributed and balanced binary tree and transmitting the matched data to the nodes that are interested in the data. The experimental results show that the system can effectively support large-scale data distribution in a dynamic network, reducing distribution costs and matching delays.