A Novel Cooperative Caching Scheme for Wireless Ad Hoc Networks: GroupCaching

Abstract

In the mobile ad hoc network, a mobile host can communicate with others anywhere and anytime. Cooperative caching scheme can improve the accessibility of data objects. However, the cache hit ratio is reduced and access latency becomes longer significantly due to the mobility of MHs, energy consumption in battery, and limited wireless bandwidth. In this paper, we propose a novel cooperative caching scheme called GroupCaching (GC) which allows each MH and its 1-hop neighbors form a group. The caching status is exchanged and maintained periodically in a group. By using the proposed GroupCaching, the caching space in MHs can be efficiently utilized and thus the redundancy of cached data is decreased and the average access latency is reduced. We evaluate the performance of the GroupCaching by using NS2 and compare it with the existing schemes such as CacheData and ZoneCooperative. The experimental results show that the cache hit ratio is increased by about 3%~30% and the average latency is reduced by about 5%~25% compared with other schemes.