Speed Comparisons of Block Ciphers on a Pentium
Algorithm Clock cycles per round # of rounds # of clock cycles per byte encrypted Notes
Blowfish91618Free, unpatented
Khufu/Khafre53220Patented by Xerox
RC5121623Patented by RSA Data Security
DES18164556-bit key
IDEA50850patented by Ascom-Systec

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