基于运动相似性的机会网络缓存管理策略

Cache management algorithm based on mobility similarity in opportunistic network

考虑机会网络节点移动相似性以及节点是否适合传输消息的判断对消息传输效率的影响,提出一种基于运动相似性的缓存管理策略。通过分析网络中消息副本扩散程度和节点的移动特性,估计缓存中消息待传输概率;结合节点运动、消息运动以及节点与消息运动的相似性,计算消息在节点中存储和转发的效用值;根据效用值选择适合节点转发的消息集合,确定在节点缓存溢出时需要丢弃消息的顺序。仿真结果表明,与ENMP、DY、CMA-MS等缓存管理策略相比,该策略具备较高的网络投递率、较低网络开销和传输时延。

Making full use of the similarity of node mobility which is used to judge whether the node is suitable for messages transmission and considering its influences on messages delivery ratio,a cache management strategy using motion similarity was proposed.The probability of message transmission in the cache was estimated by analyzing the diffusion degree of message replicas and the moving characteristics of nodes in the network,and node motion similarity and message motion similarity were combined to estimate utility of message storage and forwarding.The set of messages that was appropriate for node forwarding was selected and the order was determined in which the message needed to be discarded when the node buffer overflowed based on utility value.Simulation results show that the proposed strategy has higher delivery rate,lower cost and transmission delay compared with other cache management strategies.