Performance Model for a Cache Enabled Content Distribution Framework over MANET

On-path caching has been proved to be effective in shortening the content retrieval time and educing the traffic workload imposed on the underlying network. In this paper, we study the effectiveness of on-path caching for the content distribution in the wireless network environment with GPSR as the underlying routing protocol. We extend the general cache network model introduced in [14] to account for GPSR´s loopy paths. We further develop the performance models to take into account the effect of wireless link loss, different error recovery strategies, and the GPSR routing induced long and loopy paths. The performance models allow us to assess the average content availability, the average number of messages per content retrieval, and the average content retrieval latencies for an on-path caching enabled content distribution network over MANETs. The results show that on-path caching can significantly improve the content availability, reduce the average number of required messages to acquire a content object, and shorten the content retrieval latency. In addition, the study shows that the on-path caching is able to mitigate the negative impact caused by the long and loopy paths due to the GPSR routing.