Efficient homophonic coding

Efficient homophonic coding

Homophonic coding, or homophonic substitution, is referred to as a technique that contributes to reliability of the secret-key cipher systems. Its main goal is to convert the plaintext into a sequence of completely random (equiprobable and independent) code letters. In solving this problem three characteristics are to be considered: i) redundancy, defined as the difference between the mean code...

A Universal Algorithm for Homophonic Coding

Efficient Cryptanalysis of Homophonic Substitution Ciphers

Substitution ciphers are among the earliest methods of encryption. Examples of classic substitution ciphers include the well-known simple substitution and the less well-known homophonic substitution. Simple substitution ciphers are indeed simple, both in terms of their use and their cryptanalysis. Homophonic substitutions—in which a plaintext symbol can map to more than one ciphertext symbol—ar...

Efficient Attacks on Homophonic Substitution Ciphers

Efficient Attacks On Homophonic Substitution Ciphers by Amrapali Dhavare Substitution ciphers are one of the earliest types of ciphers. Examples of classic substitution ciphers include the well-known simple substitution and the less well-known homophonic substitution. Although simple substitution ciphers are indeed simple both in terms of their use and attacks; the homophonic substitution ciphe...

Equivolcations for Homophonic Ciphers

Substitution ciphers can be quite weak when the probability distribution of the message letters is distinctly non-uniform. A timehonoured solution to remove this weakness is to "split" each high-pro bability letter into a number of "homophones" and use a substitution cipher for the resulting extended alphabet. Here the performance of a homophonic cipher is studied from a 'Shannon-theoretic poin...