A cooperative caching algorithm for multi-cell data broadcasting

Broadcasting is an effective technique to reduce network traffic, and is inherently supported by wireless networks. It thus has been advocated by numerous on-demand data access protocols. In a wireless cellular network, broadcasting can be implemented within a single cell. However, the data owned by different cells could be different. If a client requests a data item available only in a remote cell, an inter-cell data transmission over some wired link is needed, which introduces additional access delay. In this paper, we demonstrate that such delay can be minimized through the use of remote caching. Specifically, we propose a novel cooperative caching scheme, in which each cell dynamically allocates the cache spaces for data from different remote cells. It makes replacement decisions according to several important factors: data item access frequency, cell traffic, and retrieval delay. Simulation results show that the proposed scheme can significantly reduce the response time over the non-cooperative caching scheme under various system configurations.