# Information Theoretic Security for Broadcasting of Two Encrypted Sources under Side-Channel Attacks

## TL;DR

This paper investigates the security of broadcasting two encrypted sources against side-channel attacks, providing conditions for exponential decay of information leakage using information-theoretic methods.

## Contribution

It introduces a post encryption coding framework and explicit conditions to ensure security against side-channel attacks in broadcast encryption.

## Key findings

- Explicit sufficient condition for exponential decay of information leakage
- Framework for secure broadcasting of two encrypted sources
- Analysis of side-channel attack resilience

## Abstract

We consider the secure communication problem for broadcasting of two encrypted sources. The sender wishes to broadcast two secret messages via two common key cryptosystems. We assume that the adversary can use the side-channel, where the side information on common keys can be obtained via the rate constraint noiseless channel. To solve this problem we formulate the post encryption coding system. On the information leakage on two secrete messages to the adversary, we provide an explicit sufficient condition to attain the exponential decay of this quantity for large block lengths of encrypted sources.