Split-Cache: A holistic caching framework for improved network performance in wireless ad hoc networks

Wireless ad hoc networks (WAHNs) consist of autonomous nodes cooperating with each other to transmit/receive data over multiple-hops in the network. Caching is a useful mechanism to leverage this cooperation. Nodes with cached content can satisfy requests from other nodes, thus helping reduce network traffic and energy consumption, and improve latency. With the proliferation of wireless devices on the Internet and the proposal of a future Internet with emphasis on in-network caching, improvements in caching can significantly improve network response while reducing network load. In this paper, we present a holistic caching framework, Split-Cache, which enables a network node to account for the frequency of requests of data items and their presence in the network, and to leverage a split-cache (one part caches popular items and the other caches less popular items) to make caching and cache-eviction decisions. We performed exhaustive simulations to compare Split-Cache with the state-of-the-art: Split-Cache improved the cache request resolution time on an average by 30% (and as high as 72%), and required 15% less average traffic for resolving requests-large savings when considering large number of requests.