IEEE802.11无线局域网的区分服务机制研究

Research on Differentiation Mechanism in IEEE 802.11 WLAN

文中探讨了在IEEE802.11无线局域网中提供区分服务的有关问题,分析了有线网络中提供区分服务的QoS机制不适用于无线网络的原因,介绍了IEEE802.11媒体访问控制层上的一种基于初始竞争窗口CWmin的按节点区分的优先级机制,并在此基础上给出了基于流的区分方法。仿真实验表明,基于节点的优先级区分机制对UDP流已经可以达到比较理想的效果,而对于TCP流效果并不明显,但基于流的区分服务机制能够对TCP流进行很好的区分。

This paper discusses the issue of providing differentiated services in the IEEE 802.11 wireless LAN. It analyzes the reason why the QoS mechanisms intended to provide differentiation in wireline networks does not apply to wireless networks. Then it describes a CWmin based pernode priority differentiation mechanisms and further introduces a perflow differentiation mechanism. This paper shows via simulation that per node differentiation performs well with UDP but does not work with TCP flows. However, perflow differentiation mechanism shows much better results with TCP flows.