P2P content sharing in spontaneous multi-hop wireless networks

Spontaneous multi-hop wireless networks provide a new environment for sharing content among communities of end users. Nodes interested in some content can share it on a multi-hop basis by relying on the collaboration of intermediate nodes. Organizing the communication overlay in such an environment is then a challenging task especially given the mobility of the nodes, the interference, and the scarcity of resources. In this work, we propose and implement a general, stand-alone and efficient P2P content sharing protocol for wireless ad hoc networks. We consider general and realistic scenarios ranging from a single overlay to multiple overlays coexisting in the same network, and for every single overlay, we consider different peer densities in the network. The main challenges are overlay disconnections, routing overhead, low sharing opportunities and instability of distant paths. Our protocol proposes efficient solutions for these problems leading to the best download times while guaranteeing the maximum sharing opportunities among the peers. We validate our protocol through extensive simulations and experimentations on the ORBIT platform.