Physical Layer Security in Wireless Communications

Physical layer security has recently become an emerging technique to complement and significantly improve the communication security of wireless networks. Compared to cryptographic approaches, physical layer security is a fundamentally different paradigm where secrecy is achieved by exploiting the physical layer properties of the communication system, such as thermal noise, interference, and the time-varying nature of fading channels.Written by pioneering researchers, Physical Layer Security in Wireless Communications supplies a systematic overview of the basic concepts, recent advancements, and open issues in providing communication security at the physical layer. It introduces the key concepts, design issues, and solutions to physical layer security in single-user and multi-user communication systems, as well as large-scale wireless networks.The book starts with a brief introduction to physical layer security. The rest of the book is organized into four parts based on the different approaches used for the design and analysis of physical layer security techniques: Information Theoretic Approaches: introduces capacity-achieving methods and coding schemes for secure communication, as well as secret key generation and agreement over wireless channels Signal Processing Approaches: covers recent progress in applying signal processing techniques to design physical layer security enhancements Game Theoretic Approaches: discusses the applications of game theory to analyze and design wireless networks with physical layer security considerations Graph Theoretic Approaches: presents the use of tools from graph theory and stochastic geometry to analyze and design large-scale wireless networks with physical layer security constraints Presenting high-level discussions along with specific examples, illustrations, and references to conference and journal articles, this is an ideal reference for postgraduate students, researchers, and engineers that need to obtain a macro-level understanding of physical layer security and its role in future wireless communication systems.

Fundamentals of Physical Layer Security Information-Theoretic Secrecy Shannon’s Cipher System and Perfect SecrecyInformation-Theoretic Secrecy Metrics Secret Communication Over Noisy Channels Wiretap Channel Model Coding Mechanisms for Secret CommunicationSecret-Key Generation from Noisy Channels Channel Model for Secret-Key Generation Coding Mechanisms for Secret-Key Generation ConclusionReferences Coding for Wiretap ChannelsCoding for the Wiretap Channel II Basics of Error Correcting Codes Wiretap II Codes Wiretap Coding with Polar Codes Polar Codes Polar Wiretap Codes Coding for Gaussian Wiretap Channels Error Probability and Secrecy Gain Unimodular Lattice CodesConclusion References LDPC Codes for the Gaussian Wiretap Channel Channel Model and Basic NotionsCoding for Security Asymptotic Analysis Optimized Puncturing Distributions Reducing SNR Loss Finite Block LengthsSystem Aspects Concluding Remarks ReferencesKey Generation From Wireless Channels Introduction Information Theoretic Models for Key Generation Key Generation via Unlimited Public Discussion Key Generation with Rate Constraint in Public Discussion Key Generation with Side-information at Eve Basic Approaches for Key Generation via Wireless Networks A Joint Source-Channel Key Agreement Protocol Key Agreement With a Public Channel Key Agreement Without a Public Channel Relay-Assisted Key Generation With a Public Channel Relay-Assisted Key Generation with One Relay Relay-Assisted Key Generation with Multiple Relays Relay-Oblivious Key Generation Key Agreement with the Presence of an Active Attacker Training Phase Key Generation PhaseConclusionAcknowledgementReferencesSecrecy With FeedbackIntroduction The Gaussian Two-Way Wiretap Channel Achieving Secrecy using Public Discussion Achieving Secrecy using Cooperative Jamming Full Duplex Node Half Duplex Node Achieving Secrecy through Discussion and Jamming Jamming with Codewords Secrecy Through Key Generation Block Markov Coding SchemeWhen the Eavesdropper Channel States Are Not Known Converse Outer Bounds Discussion Conclusion Proof of Theorem 5.7.5 Proof of Theorem 5.7.6References MIMO Signal Processing Algorithms for Enhanced Physical Layer Security Introduction Physical-Layer Security Signal Processing Aspects Secrecy Performance Metrics The Role of CSI MIMO Wiretap Channels Complete CSI Partial CSIMIMO Wiretap Channel with an External HelperMIMO Broadcast Channel MIMO Interference Channel MIMO Relay Wiretap Networks Relay-Aided Cooperation Untrusted Relaying Conclusions References Discriminatory Channel Estimation for Secure Wireless CommunicationIntroduction Discriminatory Channel Estimation – Basic Concept DCE via Feedback and Retraining Two-Stage Feedback-and-Retraining Multiple Stage Feedback and Retraining Simulation Results and Discussions Discriminatory Channel Estimation via Two-Way Training Two-Way DCE Design for Reciprocal Channels Two-Way DCE Design for Non-Reciprocal Channels Simulation Results and Discussions Conclusions and Discussions Acknowledgement References Physical Layer Security in OFDMA Networks Introduction Related Works on Secure OFDM/OFDMA Networks Secure OFDM Channel Secure OFDMA Cellular Networks Secure OFDMA Relay Networks Secure OFDM with Implementation Issues Basics of Resource Allocation for Secret Communications Power Allocation Law for Secrecy Multiple Eavesdroppers Resource Allocation for Physical Layer Security in OFDMA Networks Problem Formulation Optimal Policy Suboptimal Algorithm Complexity Numerical Examples Discussion on False CSI Feedback Conclusions and Open Issues References The Application of Cooperative Transmissions to Secrecy CommunicationsIntroduction When all Nodes are Equipped with a Single Antenna Cooperative Jamming Relay Chatting MIMO Relay Secrecy Communication Scenarios When CSI of eavesdroppers Is known When CSI of eavesdroppers Is unknownConclusion Acknowledgement References Game Theory for Physical Layer Security on Interference Channels Introduction System Models and Scenarios Standard MISO Interference Channel MISO Interference Channel with Private Messages MISO Interference Channel with Public Feedback and Private Messages Discussion and Comparison of Scenarios Non-Cooperative Solutions Non-Cooperative Games in Strategic Form Solution for the MISO Interference Channel Scenarios Cooperative Solutions Bargaining Solutions Nash Bargaining Solution Bargaining Algorithm in the Edgeworth-Box Walras Equilibrium Solution Illustrations and Discussions Comparison of Utility Regions Non-Cooperative and Cooperative Operating Points Bargaining Algorithm Behaviour Conclusions Appendix: Proofs Proof of Theorem 10.3.1 Proof of Theorem 10.4.1 Proof of Theorem 10.4.2 Proof of Theorem 10.4.3 References Ascending Clock Auction for Physical Layer Security Introduction Cooperative Jamming for Physical Layer Security Game Theory Based Jamming Power Allocation Ascending Auctions Chapter OutlineSystem Model and Problem Formulation System Model Source’s Utility Function Jammer’s Utility Function Auction-Based Jamming Power Allocation Schemes 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) Power Allocation Scheme based on Alternative Ascending Clock Auction (P-ACA-A)Properties of the Proposed Auction-Based Power Allocation Schemes Optimal Jamming Power for Each Source Convergence Cheat-Proof Social Welfare Maximization Complexity and Overhead Conclusions and Open Issues References Relay and Jammer Cooperation as a Coalitional Game Introduction Cooperative Relaying and Cooperative Jamming Relay and Jammer Selection Coalitional Game Theory Chapter Outline System Model and Problem Formulation Relay and Jammer Cooperation as a Coalitional Game Coalitional Game Definition Properties of the Proposed Coalitional Game Coalition Formation Algorithm Coalition Formation Concepts Merge-and-Split Coalition Formation Algorithm Conclusions and Open Issues References Stochastic Geometry Approaches to Secrecy in Large Wireless Networks Introduction Motivation Stochastic Geometry Approaches Secrecy Graph Network and Graph Model Local Connectivity Properties Global Connectivity Properties Connectivity Enhancements Secrecy Transmission Capacity Network Model Capacity Formulation Illustrative Example Current Limitations and Future Directions References Physical Layer Secrecy in Large Multi-Hop Wireless Networks Introduction Background: Physical-Layer Security in One-Hop Networks Secure Connectivity: The Secrecy Graph Secure Capacity Background: Throughput Scaling in Large Wireless Networks Secrecy Scaling with Known Eavesdropper Location Secrecy Scaling with Unknown Eavesdropper Locations Conclusion and Future Work Acknowledgement References

Xiangyun Zhou is a Lecturer at the Australian National University.He received the B.E. (hons.) degree in electronics and telecommunications engineering and the Ph.D. degree in telecommunications engineering from the ANU in 2007 and 2010, respectively. From June 2010 to June 2011, he worked as a postdoctoral fellow at UNIK - University Graduate Center, University of Oslo, Norway. His research interests are in the fields of communication theory and wireless networks, including MIMO systems, relay and cooperative communications, heterogeneous and small cell networks, ad hoc and sensor wireless networks, physical layer security, and wireless power transfer. Dr. Zhou serves on the editorial boards of Security and Communication Networks (Wiley) and Ad Hoc & Sensor Wireless Networks. He was the organizer and chair of the special session on "Stochastic Geometry and Random Networks" in 2013 Asilomar Conference on Signals, Systems, and Computers. He has also served as the TPC member of major IEEE conferences. He is a recipient of the Best Paper Award at the 2011 IEEE International Conference on Communications.Lingyang Song is a Professor at Peking University, China. He received his PhD from the University of York, UK, in 2007, where he received the K. M. Stott Prize for excellent research. He worked as a postdoctoral research fellow at the University of Oslo, Norway, and Harvard University, until rejoining Philips Research UK in March 2008. In May 2009, he joined the School of Electronics Engineering and Computer Science, Peking University, China, as a full professor. His main research interests include MIMO, OFDM, cooperative communications, cognitive radio, physical layer security, game theory, and wireless ad hoc/sensor networks. He is co-inventor of a number of patents (standard contributions), and author or co-author of over 100 journal and conference papers. He is the co-editor of two books, "Orthogonal Frequency Division Multiple Access (OFDMA)-Fundamentals and Applications" and "Evolved Network Planning and Optimization for UMTS and LTE", published by Auerbach Publications, CRC Press, USA. Dr. Song received several Best Paper Awards, including one in IEEE International Conference on Wireless Communications, Networking and Mobile Computing (WiCOM 2007), one in the First IEEE International Conference on Communications in China (ICCC 2012), one in the 7th International Conference on Communications and Networking in China (ChinaCom2012), and one in IEEE Wireless Communication and Networking Conference (WCNC2012). Dr. Song is currently on the Editorial Board of IEEE Transactions on Wireless Communications, Journal of Network and Computer Applications, and IET Communications. He is the recipient of 2012 IEEE Asia Pacific (AP) Young Researcher Award. Yan Zhang received a Ph.D. degree from Nanyang Technological University, Singapore. Since August 2006 he has been working with Simula Research Laboratory, Norway. He is currently a senior research scientist at Simula Research Laboratory. He is an associate professor (part-time) at the University of Oslo, Norway. He is a regional editor, associate editor, on the editorial board, or guest editor of a number of international journals. He is currently serving as Book Series Editor for the book series on Wireless Networks and Mobile Communications (Auerbach Publications, CRC Press, Taylor & Francis Group). He has served or is serving as organizing committee chair for many international conferences, including AINA 2011, WICON 2010, IWCMC 2010/2009, BODYNETS 2010, BROADNETS 2009, ACM MobiHoc 2008, IEEE ISM 2007, and CHINACOM 2009/2008. His research interests include resource, mobility, spectrum, energy, and data management in wireless communications and networking.