Secret Key Agreement from Correlated Gaussian Sources by Rate Limited Public Communication

TL;DR

This paper derives a closed-form expression for the optimal trade-off between secret key rate and public communication rate in Gaussian source-based key agreement, highlighting differences from discrete source scenarios.

Contribution

It provides the first explicit formula for one-way public communication protocols in Gaussian key agreement, clarifying fundamental differences from discrete sources.

Findings

Closed-form expression for optimal key-public communication trade-off.

Distinct characteristics of Gaussian sources compared to discrete sources.

Enhanced understanding of continuous source-based secret key agreement.

Abstract

We investigate the secret key agreement from correlated Gaussian sources in which the legitimate parties can use the public communication with limited rate. For the class of protocols with the one-way public communication, we show a closed form expression of the optimal trade-off between the rate of key generation and the rate of the public communication. Our results clarify an essential difference between the key agreement from discrete sources and that from continuous sources.