Strong Secrecy and Stealth for Broadcast Channels with Confidential Messages

TL;DR

This paper extends the analysis of confidential broadcast channels from weak to strong secrecy, providing new bounds and techniques for ensuring message confidentiality in a two-user setting.

Contribution

It introduces a strong secrecy criterion for broadcast channels with confidential messages, building upon and extending previous weak secrecy results using advanced divergence bounding techniques.

Findings

Achieved strong secrecy guarantees for broadcast channels with two confidential messages.

Extended existing resolvability techniques to strengthen secrecy criteria.

Provided theoretical bounds on information leakage under the new secrecy conditions.

Abstract

We consider a discrete memoryless broadcast channel consists of two users and a sender. The sender has two independent confidential messages for each user. We extend the work of Liu et al.\ on broadcast channels with two confidential messages with weak secrecy criterion to strong secrecy. Our results are based on an extension of the techniques developed by Hou and Kramer on bounding Kullback-Leibler divergence in context of \textit{resolvability} and \textit{effective secrecy}.