Cryptography for Network and Information Security

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Role of Cryptanalysis

A discipline related to cryptography is cryptanalysis, defined as the science of interpreting ciphertext. These two disciplines combined form the science of cryptology. The cryptographer's goal is to provide security for information by developing strong cryptosystems, while the cryptanalyst's goal is to discover weaknesses or flaws in cryptosystems and break the security provided by those systems. Professional cryptanalysts perform an important role in evaluating and corroborating the strength of cryptosystems. In fact, cryptosystems are generally not considered secure until they withstand significant cryptanalysis.

Cryptanalysts can use powerful computing equipment and a variety of procedures, processes, and techniques to launch attacks against cryptosystems. In fact, a good cryptanalyst can even determine plaintext from samples of ciphertext without even knowing the cipher that was used to produce it.

Cryptanalysis can also be used illegitimately for illicit gain. Knowledgeable intruders can use cryptanalysis techniques as part of their attacks against your cryptography-based security systems. When properly implemented, standard cryptography-based security technologies can provide ample protection against a wide range of attacks, including common cryptanalysis techniques. However, to obtain highly valuable information, skilled intruders or trained espionage agents with access to powerful computing resources might have the incentive to launch expensive and highly sophisticated cryptanalyst attacks. Stopping sophisticated cryptanalyst attacks requires highly secure systems that use strong cryptography-based security technologies.

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