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A CDE Definition

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(International Data Encryption Algorithm) A secret key cryptography method that uses a 128-bit key. Introduced in 1992, its European patent is held by Ascom-Tech AG, Solothurn, Switzerland. Written by Xuejia Lai and James Massey, it uses the block cipher method that breaks the text into 64-bit blocks before encrypting them. See PGP.


(1) See Personal Genome Project.

(2) (Pretty Good Privacy) A data encryption program from PGP Corporation, Palo Alto, CA ( Published as freeware in 1991 and widely used around the world for encrypting email messages and securing files, PGP is available for commercial use and as freeware for personal use. Freeware versions are also available from PGP also supports digital signatures and PKI.

The Public Key Sends the Secret Key
For email, PGP sends the key and encrypted message at the same time. It encrypts the key using a public key algorithm such as RSA and encrypts the message using a secret key algorithm such as IDEA (the original), CAST5, Triple DES and AES. On the receiving side, the public key method decrypts the secret key first, which it uses to decrypt the message.

To Network Associates and Back
PGP was developed by Phil Zimmermann (, founder of Pretty Good Privacy, Inc., San Mateo, CA, and recipient of numerous awards for his pioneering work in cryptography. In 1997, Network Associates acquired his company, and the IETF formed the OpenPGP working group to support an open PGP standard. In 2002, the PGP assets of Network Associates were acquired by the newly formed PGP Corporation, and Zimmermann became a consultant to the company. See cryptography, digital signature and web of trust.

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IDE controlleridentification
IDE fileidentifier
IDE host adapteridentity
IDE interfaceIdentity 2.0
IDE/PATAidentity and access management
IDE RAIDidentity certificate

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