Principles of Physical Layer Security in Multiuser Wireless Networks: A Survey

This paper provides a comprehensive review of the domain of physical layer security in multiuser wireless networks. The essential premise of physical-layer security is to enable the exchange of confidential messages over a wireless medium in the presence of unauthorized eavesdroppers without relying on higher-layer encryption. This can be achieved primarily in two ways: without the need for a secret key by intelligently designing transmit coding strategies, or by exploiting the wireless communication medium to develop secret keys over public channels. The survey begins with an overview of the foundations dating back to the pioneering work of Shannon and Wyner on information-theoretic security. We then describe the evolution of secure transmission strategies from point-to-point channels to multiple-antenna systems, followed by generalizations to multiuser broadcast, multiple-access, interference, and relay networks. Secret-key generation and establishment protocols based on physical layer mechanisms are subsequently covered. Approaches for secrecy based on channel coding design are then examined, along with a description of inter-disciplinary approaches based on game theory and stochastic geometry. The associated problem of physical-layer message authentication is also introduced briefly. The survey concludes with observations on potential research directions in this area.Comment: 23 pages, 10 figures, 303 refs. arXiv admin note: text overlap with arXiv:1303.1609 by other authors. IEEE Communications Surveys and Tutorials, 201

Rateless codes-based secure communication employing transmit antenna selection and harvest-to-jam under joint effect of interference and hardware impairments

In this paper, we propose a rateless codes-based communication protocol to provide security for wireless systems. In the proposed protocol, a source uses the transmit antenna selection (TAS) technique to transmit Fountain-encoded packets to a destination in presence of an eavesdropper. Moreover, a cooperative jammer node harvests energy from radio frequency (RF) signals of the source and the interference sources to generate jamming noises on the eavesdropper. The data transmission terminates as soon as the destination can receive a sufficient number of the encoded packets for decoding the original data of the source. To obtain secure communication, the destination must receive sufficient encoded packets before the eavesdropper. The combination of the TAS and harvest-to-jam techniques obtains the security and efficient energy via reducing the number of the data transmission, increasing the quality of the data channel, decreasing the quality of the eavesdropping channel, and supporting the energy for the jammer. The main contribution of this paper is to derive exact closed-form expressions of outage probability (OP), probability of successful and secure communication (SS), intercept probability (IP) and average number of time slots used by the source over Rayleigh fading channel under the joint impact of co-channel interference and hardware impairments. Then, Monte Carlo simulations are presented to verify the theoretical results.Web of Science217art. no. 70

A Survey on Wireless Security: Technical Challenges, Recent Advances and Future Trends

This paper examines the security vulnerabilities and threats imposed by the inherent open nature of wireless communications and to devise efficient defense mechanisms for improving the wireless network security. We first summarize the security requirements of wireless networks, including their authenticity, confidentiality, integrity and availability issues. Next, a comprehensive overview of security attacks encountered in wireless networks is presented in view of the network protocol architecture, where the potential security threats are discussed at each protocol layer. We also provide a survey of the existing security protocols and algorithms that are adopted in the existing wireless network standards, such as the Bluetooth, Wi-Fi, WiMAX, and the long-term evolution (LTE) systems. Then, we discuss the state-of-the-art in physical-layer security, which is an emerging technique of securing the open communications environment against eavesdropping attacks at the physical layer. We also introduce the family of various jamming attacks and their counter-measures, including the constant jammer, intermittent jammer, reactive jammer, adaptive jammer and intelligent jammer. Additionally, we discuss the integration of physical-layer security into existing authentication and cryptography mechanisms for further securing wireless networks. Finally, some technical challenges which remain unresolved at the time of writing are summarized and the future trends in wireless security are discussed.Comment: 36 pages. Accepted to Appear in Proceedings of the IEEE, 201

Secure communication protocol design for buffer-aided relaying systems

指導教員：姜　暁

Opportunistic relaying and random linear network coding for secure and reliable communication

Opportunistic relaying has the potential to achieve full diversity gain, while random linear network coding (RLNC) can reduce latency and energy consumption. In recent years, there has been a growing interest in the integration of both schemes into wireless networks in order to reap their benefits, while considering security concerns. This paper considers a multi-relay network, where relay nodes employ RLNC to encode confidential data and transmit coded packets to a destination in the presence of an eavesdropper. Four relay selection protocols are studied covering a range of network capabilities, such as the availability of the eavesdropper's channel state information or the possibility to pair the selected relay with a node that intentionally generates interference. For each case, expressions for the probability that a coded packet will not be recovered by a receiver, which can be either the destination or the eavesdropper, are derived. Based on those expressions, a framework is developed that characterizes the probability of the eavesdropper intercepting a sufficient number of coded packets and partially or fully recovering the confidential data. Simulation results confirm the validity and accuracy of the theoretical framework and unveil the security-reliability trade-offs attained by each RLNC-enabled relay selection protocol

Security-reliability tradeoff analysis of artificial noise aided two-way opportunistic relay selection

In this paper, we investigate the physical-layer security of cooperative communications relying on multiple twoway relays using the decode-and-forward (DF) protocol in the presence of an eavesdropper, where the eavesdropper appears to tap the transmissions of both the source and of the relay. The design-tradeoff to be resolved is that the throughput is improved by invoking two-way relaying, but the secrecy of wireless transmissions may be degraded, since the eavesdropper may overhear the signals transmitted by both the source and relay nodes. We conceive an artificial noise aided two-way opportunistic relay selection (ANaTWORS) scheme for enhancing the security of the pair of source nodes communicating with the assistance of multiple two-way relays. Furthermore, we analyze both the outage probability and intercept probability of the proposed ANaTWORS scheme, where the security and reliability are characterized in terms of the intercept probability and the security outage probability. For comparison, we also provide the security-reliability tradeoff (SRT) analysis of both the traditional direct transmission and of the one-way relaying schemes. It is shown that the proposed ANaTWORS scheme outperforms both the conventional direct transmission and the one-way relay methods in terms of its SRTs. More specifically, in the low main-userto- eavesdropper ratio (MUER) region, the proposed ANaTWORS scheme is capable of guaranteeing secure transmissions, whereas no SRT gain is achieved by the conventional one-way relaying. In fact, the one-way relaying scheme may even be inferior to the traditional direct transmission scheme in terms of its SRT

Characterisation and performance analysis of random linear network coding for reliable and secure communication

In this thesis, we develop theoretical frameworks to characterize the performance of Random Linear Network Coding (RLNC), and propose novel communication schemes for the achievement of both reliability and security in wireless networks. In particular, (i) we present an analytical model to evaluate the performance of practical RLNC schemes suitable for low-complexity receivers, prioritized (i.e., layered) coding and multi-hop communications, (ii) investigate the performance of RLNC in relay assisted networks and propose a new cross-layer RLNC-aided cooperative scheme for reliable communication, (iii) characterize the secrecy feature of RLNC and propose a new physical-application layer security technique for the purpose of achieving security and reliability in multi-hope communications. At first, we investigate random block matrices and derive mathematical expressions for the enumeration of full-rank matrices that contain blocks of random entries arranged in a diagonal, lower-triangular or tri-diagonal structure. The derived expressions are then used to model the probability that a receiver will successfully decode a source message or layers of a service, when RLNC based on non-overlapping, expanding or sliding generations is employed. Moreover, the design parameters of these schemes allow to adjust the desired decoding performance. Next, we evaluate the performance of Random Linear Network Coded Cooperation (RLNCC) in relay assisted networks, and propose a cross-layer cooperative scheme which combines the emerging Non-Orthogonal Multiple Access (NOMA) technique and RLNCC. In this regard, we first consider the multiple-access relay channel in a setting where two source nodes transmit packets to a destination node, both directly and via a relay node. Secondly, we consider a multi-source multi-relay network, in which relay nodes employ RLNC on source packets and generate coded packets. For each network, we build our analysis on fundamental probability expressions for random matrices over finite fields and we derive theoretical expressions of the probability that the destination node will successfully decode the source packets. Finally, we consider a multi-relay network comprising of two groups of source nodes, where each group transmits packets to its own designated destination node over single-hop links and via a cluster of relay nodes shared by both groups. In an effort to boost reliability without sacrificing throughput, a scheme is proposed whereby packets at the relay nodes are combined using two methods; packets delivered by different groups are mixed using non-orthogonal multiple access principles, while packets originating from the same group are mixed using RLNC. An analytical framework that characterizes the performance of the proposed scheme is developed, and benchmarked against a counterpart scheme that is based on orthogonal multiple access. Finally, we quantify and characterize the intrinsic security feature of RLNC and design a joint physical-application layer security technique. For this purpose, we first consider a network comprising a transmitter, which employs RLNC to encode a message, a legitimate receiver, and a passive eavesdropper. Closed-form analytical expressions are derived to evaluate the intercept probability of RLNC, and a resource allocation model is presented to further minimize the intercept probability. Afterward, we propose a joint RLNC and opportunistic relaying scheme in a multi relay network to transmit confi- dential data to a destination in the presence of an eavesdropper. Four relay selection protocols are studied covering a range of network capabilities, such as the availability of the eavesdropper’s channel state information or the possibility to pair the selected relay with a jammer node that intentionally generates interference. For each case, expressions of the probability that a coded packet will not be decoded by a receiver, which can be either the destination or the eavesdropper, are derived. Based on those expressions, a framework is developed that characterizes the probability of the eavesdropper intercepting a sufficient number of coded packets and partially or fully decoding the confidential data. We observe that the field size over which RLNC is performed at the application layer as well as the adopted modulation and coding scheme at the physical layer can be modified to fine-tune the trade-off between security and reliability