Define Differential Cryptanalysis

Question

Define Differential Cryptanalysis. Explain it briefly.

Answer 1

Differential cryptanalysis is a kind of attack which can be mounted on iterative block ciphers. Such methods were first mentioned by Murphy in an attack on FEAL-4, however they were later enhanced and perfected by Biham and Shamir who employed them to attack DES. Differential cryptanalysis is fundamentally a selected plaintext attack and relies on an analysis of the evolution of the differences among two associated plaintexts as they are encrypted beneath similar key. By careful analysis of the accessible data, probabilities can be allocated to each of the possible keys and ultimately the most probable key is recognized as the accurate one.