How does one go about cryptanalysis?
Classical cryptanalysis involves an interesting combination of analytical reasoning, application of mathematical tools, pattern finding, patience, determination, and luck. The best available textbooks on the subject are the Military Cryptanalytics series [FRIE1]. It is clear that proficiency in cryptanalysis is, for the most part, gained through the attempted solution of given systems. Such experience is considered so valuable that some of the cryptanalyses performed during WWII by the Allies are still classified. Modern public-key cryptanalysis may consist of factoring an integer, or taking a discrete logarithm. These are not the traditional fare of the cryptanalyst. Computational number theorists are some of the most successful cryptanalysts against public key systems.
