Impacts of User-Selfishness on Cooperative Content Caching in Social Wireless Networks

Cooperative Caching can be an effective mechanism for reducing electronic content provisioning cost in Social Wireless Networks (SWNETs) which are formed by a collection of mobile data enabled phones physically gathering in settings such as university campus, malls, airport and other public places. In this paper, we first propose an optimal collaborative object caching policy in order to minimize the object provision cost in SWNETs with homogenous user requests and a peer-rebate model for promoting collaboration. Then using an analytical model we study the impacts of user selfishness on the provisioning cost and the earned rebate when certain nodes in an SWNET selfishly deviate from the optimal policy in order to increase their individually earned rebate. The analytical model is extensively validated by experimental results from simulated SWNETs using the network simulator ns2.