Physical Layer Security under Realistic Communication Conditions

• Applicant: Professor Dr.-Ing. Rafael Schaefer
• Subject Area: Electronic Semiconductors, Components and Circuits, Integrated Systems, Sensor Technology, Theoretical Electrical Engineering
• Term: from 2013 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 244590776

• Final Report Year: 2017

Final Report Abstract

In today’s communication systems, there is a clear architectural separation between error correction on the physical layer and security on higher layers based on cryptographic principles. There is a recent trend to address both issues jointly at the physical layer. Such physical layer security concepts exploit the imperfections of the underlying communication channel to establish security. Although this concept shows great promise, it is not yet implemented at all. The major problem is that current studies have been carried out under too idealistic communication assumptions. The aim of this project was to address the insufficiency of too idealistic communication assumptions with the aim of bringing this concept closer to practical implementation. In particular, several questions have been addressed and significant contributions have been made. First, the definition of secrecy has been re-considered and the stringent notion of strong secrecy has been studied in detail. An operational meaning has been identified which underlines its practical relevance. Second, imperfect channel knowledge has been considered by studying secure communication for compound channels and arbitrarily varying channels. The corresponding communication scenarios have been studied in detail and secrecy capacity results have been derived. Third, the asymptotic thinking of information theory has been addressed by studying the finite block length regime of the wiretap channel. The maximal secrecy rate for a fixed block length and given small but non-vanishing decoding error and information leakage has been characterized.

Publications

• “On the Continuity of the Secrecy Capacity of Compound and Arbitrarily Varying Wiretap Channels,” IEEE Transactions on Information Forensics and Security, vol. 10, no. 12, pp. 2531-2546, Dec. 2015
  H. Boche, R. F. Schaefer, and H. V. Poor
  
• “Secure Communication Under Channel Uncertainty and Adversarial Attacks,” Proceedings of the IEEE, vol. 103, no. 10, pp. 1796-1813, Oct. 2015
  R. F. Schaefer, H. Boche, and H. V. Poor
  
• “The Secrecy Capacity of Compound MIMO Gaussian Channels,” IEEE Transactions on Information Theory, vol. 61, no. 10, pp. 5535-5552, Oct. 2015
  R. F. Schaefer and S. Loyka
  
• “Finite-Blocklength Bounds for Wiretap Channels,” Proc. IEEE International Symposium on Information Theory, Barcelona, Spain, July 2016, pp. 3087-3091
  W. Yang, R. F. Schaefer, and H. V. Poor
  
• Finite-Blocklength Bounds for Wiretap Channels
  W. Yang, R. F. Schaefer, and H. V. Poor
  
• Information Theoretic Security and Privacy of Information Systems, Cambridge University Press, 2017
  R. F. Schaefer, H. Boche, A. Khisti, and H. V. Poor