PReCinCt: a scheme for cooperative caching in mobile peer-to-peer systems

Mobile peer-to-peer (MP2P) systems consist of mobile peers that collaborate with each other to complete application requirements. Information sharing in such environments is a challenging problem due to the fundamental limitations of battery power, wireless bandwidth, and users' frequent mobility. We recently proposed a novel scheme, called proximity regions for caching in cooperative MP2P networks (PReCinCt) to efficiently support scalable data retrieval in large-scale MP2P networks. In this scheme, the network topology is divided into geographical regions where each region is responsible for a set of keys representing the data. In this paper, we extend the PReCinCt scheme to facilitate consistent cooperative caching in MP2P systems. The caching scheme considers data popularity, data size and region-distance during replacement to optimize cache content of peers. PReCinCt employs a hybrid push/pull mechanism to maintain data consistency among replicas in the network. Simulation results show the cost of consistency maintenance in terms of latency and energy consumption is significantly improved in the PReCinCt scheme.