IEEE International Symposium on Information Theory (ISIT)

Repurposing Physical Layer Secret Keys: A Novel Paradigm for Common Randomness Generation

Prashanth K. H. Sheshagiri, Juan Alberto Cabrera, Frank H. P. Fitzek

Published Jul 7, 2024• 1 citation

Abstract

Identification is a new paradigm introduced for goal-oriented communication that verifies the semantics of the intended message rather than just transmitting the message bits, which is traditionally done in classical communication systems. One of the key techniques to improve randomized identification capacity is by introducing Common Randomness (CR). Physical Layer Secret Key (PLSK) is one such CR generation technique, where terminals generate secret keys based on changes in channel reciprocity between the wireless terminals and are mainly used for PHY layer encryption. However, the traditional way of evaluating PLSK techniques through bit discrepancies, bit generation rate, and entropy is not sufficient for evaluating their usefulness for identification. This paper proposes three key novel information theory paradigms that can be used alongside other mentioned parameters to evaluate key PLSK techniques for their usefulness in identification, i.e., CR rate, CR capacity, and cost function, followed by a supporting implementation using Software Defined Radio (SDR)s.

DOI: 10.1109/isit57864.2024.10619278

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