Construction of wiretap codes from ordinary channel codes

TL;DR

This paper presents a method to construct wiretap codes with strong security from existing channel codes, achieving capacity under mild conditions using a new privacy amplification theorem based on Gallager functions.

Contribution

It introduces a novel construction of wiretap codes from arbitrary channel codes that guarantees strong security and achieves capacity with minimal assumptions.

Findings

Achieves wiretap capacity with constructed codes

Provides a new privacy amplification theorem based on Gallager functions

Ensures strong security for wiretap channels

Abstract

From an arbitrary given channel code over a discrete or Gaussian memoryless channel, we construct a wiretap code with the strong security. Our construction can achieve the wiretap capacity under mild assumptions. The key tool is the new privacy amplification theorem bounding the eavesdropped information in terms of the Gallager function.