In this paper we investigate a cooperative jamming (CJ) strategy based Stackelberg security game to improve physical layer security over multiuser OFDMA networks. Each source node tries to deliver messages to its intended destination node securely in the presence of a passive eavesdropper. Fortunately, these node pairs can resort to a friendly jammer to enhance their communication. But the jamming service is not free and the friendly jammer charges each pair for some cost. Obviously there is a tradeoff between the friendly jammer and the source-destination pairs. Consequently, a two-level Stackelberg game model is proposed, where the friendly jammer plays the seller and the source-destination pairs are the buyers. We analyze the Stackelberg Equilibrium from two sides respectively and prove the existence and uniqueness of the Stackelberg Equilibrium. Correspondingly, we also develop a distributed iterative power allocation algorithm to reach the Stackelberg Equilibrium point. Numerical Results demonstrate that the system sum secrecy rate is really improved and the physical layer security performance is effectively meliorated.
In this paper we investigate a cooperative jamming (CJ) strategy based Stackelberg security game to improve physical layer security over multiuser OFDMA networks. Each source node tries to deliver messages to its intended destination node securely in the presence of a passive eavesdropper. Fortunately, these node pairs can resort to a friendly jammer to enhance their communication. But the jamming service is not free and the friendly jammer charges each pair for some cost. Obviously there is a tradeoff between the friendly jammer and the source-destination pairs. Consequently, a two-level Stackelberg game model is proposed, where the friendly jammer plays the seller and the source-destination pairs are the buyers. We analyze the Stackelberg Equilibrium from two sides respectively and prove the existence and uniqueness of the Stackelberg Equilibrium. Correspondingly, we also develop a distributed iterative power allocation algorithm to reach the Stackelberg Equilibrium point. Numerical Results demonstrate that the system sum secrecy rate is really improved and the physical layer security performance is effectively meliorated.
To improve the physical layer security in the wireless communication network with an eavesdropper and a friendly jammer, this paper make use of beamforming to aim the jamming signal's main lobe to the eavesdropper and to diminish the jamming signal to the destination node, improving the efficiency of jamming power usage. On this basis, we propose a power auction model, in which we regard the source node as the buyer and the destination node as the seller and build corresponding utility function respectively. Then by using a distributed algorithm, Stackelberg equilibrium can be reached, maximizing the system utility and obtaining the corresponding secrecy capacity.
In this paper, the problem of improving the secrecy communication for a cooperative jamming based network in which there is a friendly jammer, an eavesdropper and N pairs of sources and destinations is addressed. A Stackelberg game is formulated to tackle the joint utility maximization of the jammer and sources subject to a maximum jamming power constraint at the jammer. In this game, the jammer behaves as the leader and the sources are followers. A uniform pricing algorithm is proposed and we prove in theory that it can maximize the secrecy rate of the system. The Stackelberg equilibrium for the proposed game is characterized, and an effective distributed algorithm with guaranteed convergence is proposed. Numerical examples are presented to validate our analysis. It is shown that the proposed distributed algorithm can obtain almost the same performance as the optimal power allocation algorithm. Besides, we also investigate the performance of the proposed distributed algorithm in different scenarios. It is shown that the proposed algorithm can obtain significant improvement for secrecy rate in the sparse scenario where all the nodes are deployed sparsely. It can enhance the secrecy rate for about 0.3 dB.
In this paper, we consider a two-way relay system where the two sources can only communicate through an untrusted intermediate relay and investigate the physical layer security issue in this two-way untrusted relay scenario. Specifically, we regard the intermediate relay as an eavesdropper from which the information transmitted by the sources needs to be kept confidential, despite the fact that its cooperation in relaying this information is essential. We first indicate that a nonzero secrecy rate is indeed achievable in this two-way untrusted relay system even without the help of external friendly jammers. As for the system with friendly jammers, after further analysis, we can obtain the secrecy rate of the sources can be effectively improved by utilizing proper jamming power from the friendly jammers. Then, we formulate a Stackelberg game between the sources and the friendly jammers as a power control scheme to achieve the optimized secrecy rate of the sources, in which the sources are treated as the sole buyer and the friendly jammers are the sellers. In addition, the optimal solutions of the jamming power and the asking prices are given, and a distributed updating algorithm to obtain the Stackelberg equilibrium is provided for the proposed game. Finally, the simulation results verify the properties and efficiency of the proposed Stackelberg-game-based scheme.
Physical layer security is an emerging security area that achieves perfect secrecy data transmission between intended network nodes, while malicious nodes that eavesdrop the communication obtain zero information. The so-called secrecy capacity can be improved using friendly jammers that introduce extra interference to the eavesdroppers. We investigate the interaction between the source that transmits the useful data and friendly jammers who assist the source by "masking" the eavesdropper. To obtain distributed solution, we introduce a game theoretic approach. The game is defined such that the source pays the jammers to interfere the eavesdropper, therefore, increasing the secrecy capacity. The friendly jammers charge the source with a certain price for the jamming, and there is a tradeoff for the price. If too low, the profit of the jammers is low; and if too high, the source would not buy the "service" (jamming power) or would buy it from other jammers. To analyze the game outcome, we investigate a Stackelburg type of game and construct a distributed algorithm. Our analysis and simulation results show the effectiveness of friendly jamming and the tradeoff for setting the price. The distributed game solution is shown to have similar performances to those of the centralized one.
The physical layer security technology is a technical scheme developed in recent years to solve the problem of information security transmission in wireless communication networks. As one of the physical layer security technologies, cooperative jamming often requires collaborative nodes to actively cooperate with other nodes with secure communication requirements to transmit information. In the environment of heterogeneous wireless network, each wireless node is relatively independent, the relationship is both cooperative and competitive, and the nodes are selfish. In this paper, we study the information transmission between the source and destination nodes, and form a virtual beamforming through the cooperation of the jamming nodes to point to the malicious wiretap nodes, so as to achieve the physical layer secure communication. First, the interest distribution relationship between the source node and other cooperative interference nodes is modeled as the Stackelberg game. The source node pays the consumption of the power consumed by the cooperative jamming nodes and motivates the cooperative interference nodes to participate actively. Then, the competition relationship among all the cooperative nodes is built as a non-cooperative game, so as to promote the reasonable pricing of the consumed power when each node participates in collaboration. When the security rate between the source node and destination node is constant, the power allocation of source and cooperative nodes and the equilibrium point of power price exist and are unique. Through the combined optimization of the two games, the power pricing and power allocation can be dynamically optimized according to the change of the network environment. The simulation results show that the power dynamic allocation and power dynamic pricing have good convergence, and the source node provides a train of thought for the selection of cooperative nodes and their number.
In this paper, we investigate a cooperative wireless network with jamming-based secure communications, where a friendly jammer can transmit jamming signals to interfere the malicious eavesdropper. We find that the secrecy rate of the source-destination link can be effectively improved with the help of the friendly jammer, and each source intends to obtain optimal jamming power from the friendly jammer to maximize its secrecy rate for data transmission. We then formulate this power allocation problem as an auction game and propose two distributively auction-based power allocation schemes, which are power allocation using Traditional Ascending Clock Auction (ACA-T) and power allocation using Alternative Ascending Clock Auction (ACA-A), considering the friendly jammer as the auctioneer and the sources as the bidders. In addition, we prove that both the proposed schemes can converge in a finite number of iterations. We also prove that the ACA-A scheme is cheat-proof while the ACA-T scheme is not. Finally, simulation results are presented to demonstrate the efficiency of the proposed auction-based schemes in improving secrecy rate of wireless networks.