Multi-Task Private Semantic Communication
Amirreza Zamani, Sajad Daei, Tobias J. Oechtering, Mikael Skoglund
TL;DR
The paper tackles private semantic communication under a privacy leakage constraint in a multi-task setting. It models the disclosed data as $U=f(X)+M$, balancing privacy $I(S;U)\le\epsilon$ with goal-oriented utility $I(U;h_i(X))$, and extends from a single task to multiple prioritized tasks. Using extended FRL/SFRL constructions and a separation technique, it derives both lower and upper bounds for the single-task trade-off, and then proves that the multi-task problem decomposes into parallel single-task problems, enabling a simple, scalable noise-design approach. The results provide explicit bounds and a constructive pathway to design privacy mechanisms that are effective across tasks while guaranteeing privacy, with potential impact on efficiency and security in goal-oriented semantic communication systems.
Abstract
We study a multi-task private semantic communication problem, in which an encoder has access to an information source arbitrarily correlated with some latent private data. A user has $L$ tasks with priorities. The encoder designs a message to be revealed which is called the semantic of the information source. Due to the privacy constraints the semantic can not be disclosed directly and the encoder adds noise to produce disclosed data. The goal is to design the disclosed data that maximizes the weighted sum of the utilities achieved by the user while satisfying a privacy constraint on the private data. In this work, we first consider a single-task scenario and design the added noise utilizing various methods including the extended versions of the Functional Representation Lemma, Strong Functional Representation Lemma, and separation technique. We then study the multi-task scenario and derive a simple design of the source semantics. We show that in the multi-task scenario the main problem can be divided into multiple parallel single-task problems.
