Non-Adaptive Coding for Two-Way Wiretap Channel with or without Cost Constraints

Masahito Hayashi; Yanling Chen

doi:10.1109/tit.2023.3343362

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arXiv · 2310.13881

Non-Adaptive Coding for Two-Way Wiretap Channel with or without Cost Constraints

Masahito Hayashi·Yanling Chen

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Abstract

This paper studies the secrecy results for the two-way wiretap channel (TW-WC) with an external eavesdropper under a strong secrecy metric. Employing non-adaptive coding, we analyze the information leakage and the decoding error probability, and derive inner bounds on the secrecy capacity regions for the TW-WC under strong joint and individual secrecy constraints. For the TW-WC without cost constraint, both the secrecy and error exponents could be characterized by the conditional Rényi mutual information in a concise and compact form. And, some special cases secrecy capacity region and sum-rate capacity results are established, demonstrating that adaption is useless in some cases or the maximum sum-rate that could be achieved by non-adaptive coding. For the TW-WC with cost constraint, we consider the peak cost constraint and extend our secrecy results by using the constant composition codes. Accordingly, we characterize both the secrecy and error exponents by a modification of Rényi mutual information, which yields inner bounds on the secrecy capacity regions for the general discrete memoryless TW-WC with cost constraint. Our method works even when a pre-noisy processing is employed based on a conditional distribution in the encoder and can be easily extended to other multi-user communication scenarios.

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BibTeX RIS

Masahito Hayashi, Yanling Chen. 2023-10-21. Non-Adaptive Coding for Two-Way Wiretap Channel with or without Cost Constraints. https://doi.org/10.1109/tit.2023.3343362

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