带有节点状态估计的间断连接无线网络缓存管理策略

Cache Management Mechanism with Node Status Evaluation for Intermittently Connected Wireless Networks

针对间断连接无线网络中的节点缓存资源有限的问题,该文提出一种适用于间断连接无线网络的缓存管理机制。根据运动过程中所获得的网络状态信息,各个节点以分布式的方式估计给定节点与其他节点直接及间接连接状态、节点服务率以及节点连通强度,动态感知各个节点服务能力的差异,同时预测当前节点成功投递该消息的概率以感知消息的效用值,从而执行缓存管理操作。结果表明,与其他缓存管理机制相比,所提出的缓存管理机制不仅能够有效降低投递开销,同时大幅度地提高了消息成功投递率。

Considering the limited cache resources of nodes in intermittently connected wireless networks, a cache management mechanism is proposed based on node state estimate. The direct and indirect connection status, service rate and connectivity degree between the given nodes can be evaluated in a distributed manner, according to the network state monitored during the movement. Further, the difference of service ability of each node can be determined dynamically. Furthermore, the probability of message successfully delivered by the current node and the utility for the given message can be estimated. Consequently, cache management operations are executed reasonably. Simulation results show that the proposed mechanism does not only constrain the overhead ratio effectively but also enhance the message delivery ratio, compared with other mechanisms.