Linear cryptanalysis and security tradeoff of block ciphering systems with channel errors

Abstract

Channel errors are usually treated as an obstacle in designing an encrypted wireless system. So we are supposed to reduce them as much as possible due to the potential error bursts contributed by an avalanche effect of block ciphers. In this paper, we propose that channel errors are to be explored for the benefit of security enhancement as they could be translated to additional efforts in cryptanalysis for an adversary node. To achieve this, a system with an outer block channel coder and an inner block cipher is presented. A framework for linear cryptanalysis is established under which an eavesdropper takes advantage of linear relationship among coded symbols, as well as linear approximation of ciphers. Also presented is an analysis on the tradeoff between security enhancement and performance degradation in the presence of channel errors. © 2012 Springer-Verlag.