构建Ad Hoc网络跨层协议交互机制

Construction of Cross-Layer Interaction Mechanism for Ad Hoc Networks

Ad Hoc网络中无线信道的时变特性和网络拓扑的不断变化导致了链路的频繁断续,使得数据包大量丢失。这就要求高层应用协议能够快速访问底层传输协议甚至信道的状态信息,各层协议之间能够根据需要互相交换信息,迅速作出决策,提高分组接收成功率。基于QualNet网络仿真器设计并实现了一种网络协议栈跨层交互的机制。结果表明,利用该机制,能够快速建立跨层协议的交互,使得高层协议及时获取低层协议的有用信息,从而可根据信道的状况动态调节网络协议设置,提高分组发送成功率,优化网络传输的性能。

The time - variant property of wireless channel and changing topologies in ad hoc networks cause the frequent disconnection and connection of data links. A new protocol stack based on the cross - layer information interaction mechanism should be designed, where information of non - adjacent protocol layer can be accessed from each other. A cross - layer interaction mechanism based on QualNet is proposed and constructed in the paper to improve the performance of multimedia data transport in wireless mobile ad hoe networks. Simulation results show that the cross - layer design presented in this paper can achieve significant performance gain in term of packet loss ratio, hence improving the network transport performance.