Error Correction of Noisy Interleaved Block Ciphers

Correction of noisy cipher is a challenging task. Classical error detection and correction methods are not suitable for encrypted data. Previous work has been done on correcting noisy block ciphers using cipher and plaintext characteristics. For certain amount of errors, when error correction using cipher characteristics fails, the language properties of plaintext data were used, instead, to eliminate noise. However, this method requires an iterative process, and there are cases that may occur when unique solution cannot be achieved. In this paper, error detection and correction is performed at the receiver end, without any changes to the encryption algorithm, using only cipher characteristics. Interleaving the cipher text before transmission and deinterleaving after reception cause bursts of channel errors to be spread out in time, and, thus, to be in the correction capability of, only, cipher characteristic approach.