Secure Communications with D 2 D Cooperation

Device to Device (D2D) communication provides a promising technique for 5G wireless networks, supporting higher data rates. Security of data transmission over wireless clouds could put constraints on devices; whether to cooperate or not. Therefore, our aim is to provide analytical framework for the security at the physical layer and to define the constraints embodied with cooperation in wireless clouds . In this paper, two legitimate transmitters Alice and John cooperate to increase the reliable transmission rate received by their common legitimate receiver Bob, where one eavesdropper, Eve exists. We propose a distributed algorithm that allows the devices to select whether to cooperate or not and to adapt their optimal power allocation based on the cooperation framework selected. Moreover, we define distance constraints to enforce the benefits of cooperat ion between devices in a wireless cloud.