Dynamics of multipath network coding and multicasting in wireless P2P networks

This paper considers the problem of delivering K different contents to D destinations from N sources in wireless networks. Traffic in opposite directions over two wireless hops can utilize the advantage of network coding (NC) in order to decrease the number of transmissions used. We call such coded hops as “NC-links”. On the other hand, the multicast (MC) links can transmit data to several nodes at the same time, also yielding the improvement of the transmissions efficiency. However, there exists a certain level of ambiguity regarding how to coordinate NC and MC to improve the file sharing performance in wireless P2P content distribution systems. Considering both NC and MC gains, we investigate the content traffic splitting using the theory of a potential game and show that there is competition among destinations in order to minimize the total system transmission cost. Subsequently, we identify the equilibrium solution to this game and develop a two-level distributed control algorithm that allows each destination to select the source and split the traffic so as to adjust the content traffic based on the potential function in a distributed way. Through theoretical analysis and simulation results, we show that the proposed scheme is stable and effective.