AdHoc网络中考虑事件紧急度的跨层QoS保障机制

Urgent-based Cross Layer Algorithm for QoS Provision in Ad Hoc Networks

考虑Ad Hoc网络中事件紧急度,提出一种可以有效改善整体高优先级业务流时延和时延抖动性能的跨层QoS服务质量保障算法.根据时延要求及业务分组距离目的点的跳数信息,评估此业务的紧急度,并在调度传输时充分考虑各个事件的紧急度.在有实时要求的业务发生超时的情况下,通过合适的路由置换方法,改善业务流时延及网络吞吐量.本文重点讨论如何在IEEE802.11e协议基础上实现对指定优先级业务流的服务质量保障.GloMoSim仿真环境下的仿真结果显示该算法与原有IEEE802.11e协议相比,对于高优先级业务,在分组端到端时延、时延抖动以及网络吞吐量方面有较大的改善.

This paper proposes a urgent-based cross layer algorithm for QoS provision in Ad Hoc networks. It can effectively improve the overall performance of high priority traffic at end-to-end delay and jitter. The algorithm uses the packets＇ information of delay re- quirement and the hop left to the destination to get the urgent factor, and then taking full consideration of the packets＇ urgent factor when sending packet. When timeout occurs in Real-Time traffic, an appropriate route reverse method can be used to improve the per- formance of network throughput and end-to-end delay. How to realize the QoS guarantee for the special priority traffic is the main point in this paper. Finally, simulation results in GloMoSim prove that the proposed algorithm gets good performance at end-to-end delay, jitter and throughputs compared to previous IEEE802.11 e protocol.