Efficient One-Way Secret-Key Agreement and Private Channel Coding via Polarization

TL;DR

This paper presents explicit polarization-based schemes for one-way secret key agreement and private channel coding, achieving optimal rates and strong secrecy with linear complexity in blocklength.

Contribution

It introduces novel polarization-based methods for secret key agreement and private channel coding with linear complexity and optimal secrecy rates.

Findings

Achieves secret key rate equal to the one-way secret-key capacity.

Constructs private channel codes reaching secrecy capacity.

Ensures strong secrecy with linear encoding and decoding complexity.

Abstract

We introduce explicit schemes based on the polarization phenomenon for the tasks of one-way secret key agreement from common randomness and private channel coding. For the former task, we show how to use common randomness and insecure one-way communication to obtain a strongly secure key such that the key construction has a complexity essentially linear in the blocklength and the rate at which the key is produced is optimal, i.e., equal to the one-way secret-key rate. For the latter task, we present a private channel coding scheme that achieves the secrecy capacity using the condition of strong secrecy and whose encoding and decoding complexity are again essentially linear in the blocklength.