Papílio cryptography algorithm

Abstract

Papílio is a Feistel cipher encryption algorithm where the coder process (function F) is based in the Viterbi algorithm. The Viterbi algorithm was proposed as a solution to decode convolutional codes. There are several parameters that define the convolution code and Viterbi algorithm; one of them is the generator polynomial. To use Viterbi algorithm in cryptography, it is necessary to make some modifications. The proposed one does not depend on the parameters of Viterbi nor on the parameters of convolution. In this work we will analyze the cryptographic indices (avalanche, diffusion and confusion) of Papílio considering all possible different polynomials and fix the other parameters. © Springer-Verlag 2004.