The Physical Security For Cooperative Communication Network Using Stackelberg Game

The future communication system will allow multiple types of network terminal to join and leave the network, the network will be very vulnerable to be attacked. Any node within the scope of the communication system is possible to be eavesdropped and be intercepted the information. Although now we have high security encryption methods, the physical layer is not completely safe. Therefore, the physical layer security obtains the new attention. The physical layer security has become an emerging research domain, the purpose is to maximize the reliable information of the source node to the destination node, to make the network node to transmit the data in security. The maximum ratio is the security capacity.This paper uses the game theory approach to study the physical layer security problem in the cooperative communication, in order to achieve the maximum security capacity. Suppose that the cooperative communication model includes a source, a destination, an eavesdropper and a relay. It can reach the maximum security capacity through the relay’s noise forward or amplify forward. We propose a buyer/seller (Stackelberg) game over the cooperative communication, make the security capacity as the performance metric, and get the optimal value of the security capacity.The source and the relay are the game’s participants, and each participant is selfish and wants to maximum their own utility function. The source is defined as buyer, and the relay is defined as seller. The game is defined such that the source pays the relay to the relay’s power, therefore, increasing the security capacity. The relay charges the source with a certain price for the power. If too low, the profit of the relay is low; and if too high, the source would not buy the relay’s power or would buy it from other relays. There is a tradeoff for the price. Using well chosen amounts of power from the relay, the security capacity can be maximized. To analyze the game outcome, we investigate a Stackelburg type of game and construct a distributed algorithm, which is different from the traditional centralized algorithm. Our analysis and simulation results show the existence of equilibrium to maximize the security capacity and the effectiveness of the relay to improve the system.