摘要
异构无线网络是将不同接入技术、不同性能的网络融合到一起构成的单个逻辑网络。异构无线网络中,TCP端到端的拥塞控制机制对网络的健壮性和稳定性具有非常重要的作用,因此是网络研究的一个热点问题。针对异构无线网络中移动节点发生垂直切换时传输层性能下降的特点,提出了一种基于TCP Vegas的传输层拥塞控制算法B-Evegas。给出了垂直切换发生时的传输控制方法,垂直切换后拥塞窗口的恢复采用带宽估计与分段增加策略,并引入了快速恢复机制,在拥塞窗口过大时根据链路的时延指数性地减小拥塞窗口。仿真结果表明,该算法是合理的,可以有效提高垂直切换发生后TCP连接的吞吐量或者减小数据包的传输时延。
Heterogeneous wireless network is a logical network that is constituted by different kinds of wireless access network with different bandwidth,time delay and coverage.In heterogeneous wireless network,end to end congestion control is very important to the robust and stability.For the performance degradation of transport layer during vertical handoff,propose an improved transport congestion protocol B-Evegas based on TCP Vegas.The algorithm is consisted of transport suspension,bandwidth estimation,segmentation increase and fast recovery.The simulations results show that this algorithm is reasonable,it effectively enhances the throughput or reduce the end-to-end delay of TCP link after vertical handoff.
出处
《计算机技术与发展》
2012年第4期88-92,共5页
Computer Technology and Development
基金
江苏省科技支撑计划项目(BE2009157)
