A Short History of Cryptography

Cryptography is one of the oldest fields of technical study we can find records of, going back at least 4,000 years. It is quite noteworthy that of all the cryptosystems developed in those 4,000 years of effort, only 3 systems in widespread serious use remain hard enough to break to be of real value. One of them takes too much space for most practical uses, another is too slow for most practical uses, and the third is widely believed to contain serious weaknesses. We begin with a classification scheme for ciphers given by Gary Knight in the first of a series of articles which posed ciphers to the reader, and after a given period of time demonstrated reader solutions along with explanations of how they solved the ciphers. Versions of the solutions attained by the author were also given along with many mathematical techniques for "attacking the unknown cipher".

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