基于增强型PROPHET路由的DTN拥塞控制研究

Congestion control based on advanced PROPHET routing in DTN

DTN(delay tolerant network)网络的特点及其采用的保管传输机制使得DTN极易耗尽其有限的网络资源(缓存、带宽等),从而导致网络拥塞,降低网络性能。针对这个问题,在应用增强型PROPHET(probabilistic routing protocol using history of encounters and transitivity)路由算法的基础上,给出了一种基于归一化混合参数的缓存管理策略。应用这种缓存管理策略的DTN网络会优先丢弃归一化混合参数小的消息,以使节点获得足够接收新消息的缓存空间,从而有效地缓解拥塞。仿真结果表明,基于归一化混合参数的缓存管理策略在消息递交率、开销率及平均时延几个方面的性能表现优于应用传统缓存管理策略。

Owning to the network characteristics and custody transfer mechanism in delay tolerant network（ DTN）,there is a higher probability that DTN exhausts its network resource（ such as buffer and bandwidth）,resulting in network congestion and poor network performance. Aiming at congestion control problem in DTN,on the premise of advanced probabilistic routing protocol using history of encounters and transitivity（ PROPHET） routing algorithm,a new buffer management strategy based on normalized hybrid parameter is proposed. With the proposed buffer management strategy in DTN,once the congestion occurs,the message with least normalized hybrid parameter will be dropped,DTN nodes can obtain the buffer to receive new massages. Simulation results show that compared with the traditional buffer management strategy,the advanced PROPHET routing algorithm with the new buffer management strategy can achieve better performances in terms of maximizing message delivery probability,thus decreasing average delay and minimizing overhead ratio.