Editing Cryptanalysis (section)

{{Short description|Study of analyzing information systems in order to discover their hidden aspects}}
[[File:Cyklometr.jpg|thumb|upright=1.5|Reconstruction of the appearance of [[cyclometer]], a device used to break the encryption of the [[Enigma machine]]. Based on sketches in [[Marian Rejewski]]'s memoirs.]]
'''Cryptanalysis''' (from the [[Greek language|Greek]] ''kryptós'', "hidden", and ''analýein'', "to analyze") refers to the process of analyzing [[information system]]s in order to understand hidden aspects of the systems.<ref>{{cite web|url=http://www.nsa.gov/careers/career_fields/cryptsiganalysis.shtml |title=Cryptanalysis/Signals Analysis |publisher=Nsa.gov |date=2009-01-15 |access-date=2013-04-15}}</ref>  Cryptanalysis is used to breach [[Cryptography|cryptographic]] security systems and gain access to the contents of [[Encryption|encrypted]] messages, even if the [[key (cryptography)|cryptographic key]] is unknown.

In addition to mathematical analysis of cryptographic algorithms, cryptanalysis includes the study of [[side-channel attacks]] that do not target weaknesses in the cryptographic algorithms themselves, but instead exploit weaknesses in their implementation.

Even though the goal has been the same, the methods and techniques of cryptanalysis have changed drastically through the history of cryptography, adapting to increasing cryptographic complexity, ranging from the pen-and-paper methods of the past, through machines like the British [[Bombe]]s and [[Colossus computer]]s at [[Bletchley Park]] in [[World War II]], to the [[Mathematics|mathematically]] advanced computerized schemes of the present. Methods for breaking modern [[cryptosystem]]s often involve solving carefully constructed problems in [[pure mathematics]], the best-known being [[integer factorization]].