Exhaustive Key Search of the DES: Updates and Refinements

Abstract

Exhaustive key search is the simplest attack against a cryptosystem, but it is sometimes the most realistic. This is specially true\nfor carefully designed block ciphers for which advanced cryptanalysis\n(e.g. : linear, differential) is not applicable. In this paper, we dirst update\nthe cost of an exhaustive key search of the Data Encryption Standard\n(DES) using Field Programmable Gate Arrays (FPGAs). Then we illus-\ntrate how a time-memory tradeoff attack can be mounted for a similar\ncost, with much more dramatic consequences.