In this paper, we investigate jamming power allocation to improve physical layer security in a multiuser two-way relay network, where several communication pairs, one untrusted relay and one friendly jammer are involved. The untrusted relay helps these pairs to forward information and tries to eavesdrop simultaneously. In order to deteriorate the eavesdropping link and to improve physical layer security, we introduce a friendly jammer to impose interference on the relay. We formulate the jamming power allocation as an ACA-A game, where the friendly jammer is modeled as the auctioneer and the pairs are regarded as the bidders. The convergence and the cheat-proof property of the proposed auction are analyzed and proved. Finally, we also carry out some numerical results to validate the effectiveness of the proposed ACA-A based power allocation algorithm.
In this paper, we investigate jamming power allocation to improve physical layer security in a multiuser two-way relay network, where several communication pairs, one untrusted relay and one friendly jammer are involved. The untrusted relay helps these pairs to forward information and tries to eavesdrop simultaneously. In order to deteriorate the eavesdropping link and to improve physical layer security, we introduce a friendly jammer to impose interference on the relay. We formulate the jamming power allocation as an ACA-A game, where the friendly jammer is modeled as the auctioneer and the pairs are regarded as the bidders. The convergence and the cheat-proof property of the proposed auction are analyzed and proved. Finally, we also carry out some numerical results to validate the effectiveness of the proposed ACA-A based power allocation algorithm.
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.
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 research area that explores the possibilities of achieving perfect secrecy data transmission between sources and intended destinations, while possible malicious eavesdroppers who intend to eavesdrop the communication links obtain zero information. However, such a security is determined by the wireless channel conditions: if the channel between source and destination is worse than the channel between source and eavesdropper, the secrecy rate is typically zero. To overcome this limitation, cooperative jamming is considered as a promising approach where selected jammers can transmit jamming signals to interfere with the malicious eavesdroppers and thus the secrecy capacity can be effectively improved. In this chapter, we consider the jamming power allocation issue in a jammer-assisted cooperative wireless network. The secrecy rate of the source-destination links can be optimized utilizing a well-chosen amount of jamming power from the friendly jammer, and thus each source that can benefit intends to obtain an optimal jamming power to maximize its secrecy rate for data transmission. Then, the problem comes to how to effectively allocate the limited jamming power owned by the friendly jammer among the sources in demand to achieve an optimized system performance. By considering the friendly jammer as the auctioneer and the sources as the bidders, we formulate this power allocation problem as an auction game model, and introduce three distributed auction-based power allocation schemes, i.e., Power allocation scheme based on Single object pay-as-bid Ascending Clock Auction (P-ACA-S), Power allocation scheme based on Traditional Ascending Clock Auction (P-ACA-T), and Power Allocation Scheme based on Alternative Ascending Clock Auction (P-ACA-A). In addition, we investigate some basic properties of the proposed three auction-based power allocation schemes, i.e., convergence, cheat-proof property, and social welfare maximization.
In this paper, we consider a two-way relay network where two sources can communicate only through an unauthenticated intermediate relay node. We investigate secure communications of this two-way relay scenario using physical layer security. Specifically, we treat the relay node as an eavesdropper from whom the information transmitted by the sources needs to be kept secret, despite the fact that its cooperation in relaying this information is essential. We first find that a non-zero secrecy rate is indeed achievable in this two-way relay network even without external jammers. Further still, with the help of friendly jammers who can transmit jamming signals to distract the malicious relay, a positive gain of the secrecy rate can be realized. In order to obtain the maximum secrecy rate, we define and then analyze an optimization problem. Finally, an optimal solution of jamming power allocation is provided for the system with friendly jammers.
Physical layer security is an emerging security area that explores possibilities of achieving perfect secrecy data transmission between the intended network nodes, while possible 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. Here, we investigate the interaction between the multiple source-destination links and a friendly jammer who assists by “masking” the eavesdropper. In order to obtain a distributed solution, one possibility is to introduce a distributed auction theoretic approach. The auction is defined such that the source-destination links provide bids for the jammer to interfere the eavesdropper, therefore increasing their secrecy capacities. We propose a distributed auction using the share auction and iteratively updating the bids. To compare with the performances, we construct a centralized solution and a VCG auction, which cannot be implemented in practice. Our analysis and simulation results show the effectiveness of friendly jamming and convergence of the proposed scheme. The distributed game solution is shown to have similar performances to those of the centralized ones.
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.