Secrecy-oriented partner selection based on social trust in device-to-device communications

Device-to-device (D2D) communications recently have attracted broad attention owing to its potential ability to improve spectrum and energy efficiency within the existing cellular infrastructure. Lacking sophisticated control, D2D user equipments (DUEs) themselves are not powerful enough to resist eavesdropping or fight against security attacks. This work investigates selection of jamming partners for D2D users to thwart reception by social outcasts in D2D overlay, by exploiting social relationship to improve secrecy rate. We aim to maximize the secrecy rate of worst case, eavesdropping by any outcast, through selecting jammer node while allocating transmit power for both source and jammer. We present a heuristic genetic algorithm based solution to evaluate the problem directly. In addition, we also propose approximated optimization solutions by considering power allocation of upper and lower bounds to simplify the problem, by leveraging the fractional programming (GFP) oriented Dinkelbach-type algorithm. Numerical results show that the proposed schemes can achieve better performance through finding an appropriate partner.