__Transmission__ by Hari Kunzru. “’Mitch’, said Clay. ‘Bob and Alice.’ ‘That’s crypto,’ said Darryl.” (136)

Cryptography is the field of study dedicated to translating a message so that its contents are hidden. The power of modern computers has enabled cryptography to be standardized in security for digital information. One cryptographic standard is that of public-key cryptography where a “public-key”, E, is used to “encrypt” messages and a unique “private-key”, D, is used to “decrypt messages”. The canonical parties used for describing the use of such a system are Bob and Alice.

EG) Alice wants to send a message, M, to Bob in secrecy. Using public-key encryption, Alice encrypts the message, M, into a new message, O, by applying an encrypting function, F, to the message along with Bob’s public-key.

That is: O = F(E, M)

To decrypt the message O back to M, Bob applies F with his private-key, D.

That is: M = F(D, O) = F(D, F(E, M))

As the name suggests D is privy only to Bob. Therefore, no one but Bob can decrypt the message.

http://en.wikipedia.org/wiki/Cryptography

An Overview of Cryptography by Gary C. Kessler

Cryptography.org FAQ

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