English

Wiretap Channels: Nonasymptotic Fundamental Limits

Information Theory 2017-06-14 v1 math.IT

Abstract

This paper investigates the maximal secret communication rate over a wiretap channel subject to reliability and secrecy constraints at a given blocklength. New achievability and converse bounds are derived, which are uniformly tighter than existing bounds, and lead to the tightest bounds on the second-order coding rate for discrete memoryless and Gaussian wiretap channels. The exact second-order coding rate is established for semi-deterministic wiretap channels, which characterizes the optimal tradeoff between reliability and secrecy in the finite-blocklength regime. Underlying our achievability bounds are two new privacy amplification results, which not only refine the existing results, but also achieve stronger notions of secrecy.

Keywords

Cite

@article{arxiv.1706.03866,
  title  = {Wiretap Channels: Nonasymptotic Fundamental Limits},
  author = {Wei Yang and Rafael F. Schaefer and H. Vincent Poor},
  journal= {arXiv preprint arXiv:1706.03866},
  year   = {2017}
}

Comments

53 pages, 3 figures

R2 v1 2026-06-22T20:16:55.860Z