基于OPNET的MAC协议的研究与仿真-《计算机技术与发展》

文章信息/Info

Author(s):: ZHOU Xiao-bin; Department of Computer Science and Mathematics, Ningxia University

Keywords:: IEEE802.11 ; distribute coordination function ; binary exponential backoff algorithm; improved Markov mode

摘要:: 文中主要分析了IEEE802．11的MAC协议中的分布式协调工作模式（Distribute Coordination Function，DCF）。使用DCF方式进行访问控制时，二进制指数退避算法在竞争周期内冲突增加会使信道分配不合理，这样严重影响网络的通信吞吐量。针对影响网络吞吐量这个问题，文中首先结合了马尔科夫（Markov）的改进模型，根据节点的实时状态，设计了节点在初始竞争成功发送数据后和发生冲突时的退避算法，优化了DCF的退避机制，动态地调整了节点在不同状态时的信道获取能力，提高工节点发送数据的网络吞吐量。最后以OPNET为仿真平台证明其在吞吐量方面有所改善

Abstract:: It analyzes the distribute coordination function （DCF） of protocol for MAC in IEEE802.11. In tiler USe of access control with DCF, binary exponential backoff （BEB） algorithm in competitive cycle will increase conflict to channel allocation is not reasonable, Seriously influencing communication network throughput. Aiming at this problem, combined improved Markov model, according to node of the real-time state,design the backoff （BEB） algorithm after sending data in the initial competitive success and during the conflict. Optimize the backoff mechanism of MAC. Dynamically adjust the node in a different state channel access ability. Improve the node sending data network throughput. The new method is simulated by OPNET, the results show that the method improves performances on through-put