Adaptive cache invalidation methods in mobile environments

Caching of frequently accessed data items can reduce the bandwidth requirement in a mobile wireless computing environment. Periodically broadcast of invalidation reports is an efficient cache invalidation strategy. However, this strategy is severely affected by the disconnection and mobility of the clients. In this paper, we present two adaptive cache invalidation report methods, in which the server broadcasts different invalidation reports according to the update and query rates/patterns and client disconnection time while spending little uplink cost. Simulation results show that the adaptive invalidation methods are efficient in improving mobile caching and reducing the uplink and downlink costs without degrading the system throughput.