Impact of Selfishness in Device-to-Device Communication Underlying Cellular Networks

In a device-to-device (D2D) communication underlying cellular network, a user equipment is desired to operate cooperatively and unselfishly to transmit data as relays. However, most users more or less behave in a selfish way, which makes user selfishness a key factor that affects the performance of the whole communication system. We focus on the impact of user selfishness on D2D communications. First, we distinguish user selfishness into two types in accordance with D2D transmission modes, namely the connected transmission and opportunistic transmission modes. The user selfishness in these two types of transmissions are modeled separately. Then, we propose a time-varying graph model that characterizes the impacts of both individual and social selfishness on the D2D communications. Simulation results obtained under the realistic networking settings indicate that the interaction between connected and opportunistic selfishness worsens the impairment caused by individual selfishness. Additionally, when concerning social selfishness, inside-community selfishness can be ignored in some occasions, while otherwise its role is heavily influenced by community numbers.