对IEEE 802.11MAC层协议公平性改进的研究  

Improvement of the Fairness of IEEE 802.11 MAC Layer Protocol

作　　者：蔡志强[1] 李沛[1] 张纯鹏[1] 许胤龙[1] 

机构地区：[1]中国科学技术大学计算机科学与技术系,省部共建高性能计算与应用重点实验室,安徽合肥230027

出　　处：《计算机仿真》2008年第2期130-135,共6页Computer Simulation

摘　　要：Ad Hoc网络中基于IEEE 802.11的MAC层协议采用CSMA/CA机制,通过侦听只能获取一跳范围内节点的信息,存在隐终端问题,影响了网络流调度的公平性。文中对IEEE 802.11提出了一种修改方案,该方案通过邻居结点间的信息交换,使网络中每个节点具有其二跳范围内所有结点的信息,以发现网络中的隐终端,提高网络流调度的公平性。对比仿真实验结果表明,修改后的IEEE 802.11与原协议的网络吞吐量基本相当,但具有更好的公平性。IEEE 802.11 has been widely utilized nowadays as main MAC protocol in Ad Hoc networks. However, nodes can only access 1-hop information through overhearing with CSMA/CA mechanism embedded in IEEE 802.11. This leads to the hidden terminal problem and has a serous impact on fairness of network flows scheduling. A modification of IEEE 802.11, which employs broadcast technique to exchange information among 2 - hop neighbor nodes, is proposed in this paper. With this modification, the hidden terminals can be detected and the fairness is improved. Simulation results indicate that the modified IEEE 802.11 achieves much better fairness compared to the original IEEE 802.11 while still maintains almost the same throughput.

关 键 词：无线自组网 媒体访问控制子层协议 隐终端 公平性 

分 类 号：TN915.04[电子电信—通信与信息系统]