Secure Index Coding: Existence and Construction

TL;DR

This paper studies the conditions under which secure index codes can be constructed to protect messages from eavesdroppers with limited access, revealing that random keys are not always beneficial for security.

Contribution

It provides a necessary and sufficient condition for the existence of secure index codes against eavesdroppers with bounded message access.

Findings

Secure index codes exist under specific conditions.

Random keys do not enhance security in certain index coding scenarios.

The paper characterizes when secure index coding is feasible.

Abstract

We investigate the construction of weakly-secure index codes for a sender to send messages to multiple receivers with side information in the presence of an eavesdropper. We derive a sufficient and necessary condition for the existence of index codes that are secure against an eavesdropper with access to any subset of messages of cardinality $t$, for any fixed $t$. In contrast to the benefits of using random keys in secure network coding, we prove that random keys do not promote security in three classes of index-coding instances.