延迟容忍传感器网络中面向发布/订阅系统的事件传输

提出了一种延迟容忍无线传感器网络(delay tolerant sensor network,简称DTSN)中基于团体的发布/订阅系统事件传输协议CET(community-based event transmitting protocol).CET的核心思想是,网络中所有传感器节点依据它们的相互连通性形成若干个固定的团体(community),并基于这些团体进行事件的传输.CET协议由事件传输和队列管理两部分组成.在事件传输策略中,事件除了尽可能地传递给移动订阅者之外,移动订阅者保存的某些事件还回传给团体内的传感器节点以提高事件的传输成功率.队列管理则根据事件的成功传输次数和生存时间来共同决定存储队列中事件的重要程度和丢弃原则,以降低网络传输能耗.仿真分析表明,与直接收集DG(direct gathering)相比,CET能够以较低的事件传输能耗和传输延迟获得较高的事件传输成功率.

Event Delivery in Publish/Subscribe System for Delay Tolerant Sensor Networks

This paper proposes CET, a community based event transmitting protocol in publish/subscribe system for Delay Tolerant Sensor Networks (DTSN). The core idea of CET is that event transmitting is based on communities which are formed by sensors in the network according to their connectivity. CET consists of two key components data transmission and queue management. In data transmitting, not only events are transmitted to mobile subscribers as best as possible, some events in subscribers are also retransmitted to sensors in community, for enhancing the data delivery ratio. The queue management employs both the event survival time and the successful delivery time to decide whether the event should be transmitted or dropped for minimizing the transmission overhead. Simulation results have shown that the proposed CET achieves a higher event delivery ratio with the lower transmission overhead and event delivery delay than DG (direct gathering protocol).