一种适用于Ad Hoc网络的拥塞控制算法

Ad hoc网络是一种无基础设施、无中心控制的分布式自组织网络,在紧急情况下能够迅速搭建.目前,在IEEE802.11协议基础上所搭建的ad hoc网络面临的主要问题是在信道达到饱和时,其链路层时延明显增加,以至于其上层的协议无法正常工作.本文提出了一种结合链路层及传输层的拥塞控制算法,通过对传输层拥塞窗口的控制、以及引入报文生命期及优先级,使得网络即使在大业务量时,链路层依然能够保持很低的时延,同时大幅度地提高传输层吞吐率.最后通过仿真,验证了该算法的有效性.

A Congestion Control Algorithm for Ad Hoc Network

Ad hoc network is a kind of self-organizing network, and it requires no infrastructure, nor any central con- trol. It can be rapidly constructed under emergency conditions. A major problem for IEEE802. 11-based ad hoc network is the super high link-layer delay when the channel is fully loaded, which prevents upper-layer protocols from working properly. By introducing modifications on both transport layer and link layer, we propose a congestion control algo- rithm that employs congestion window, data packet lifetime management, and packet priority control. The algorithm significantly reduces the link-layer delay and greatly improves the throughput of the network under such conditions.