A system and method for implementing the Triple Data Encryption Algorithm
(TDEA) for the Data Encryption Standard (DES) using merger ciphers is
provided which may be configured to operate in the chain block cipher
(CBC) mode. Data blocks are enciphered using less computations in the
critical timing path significantly reducing the time required for each
round of ciphering. Two permutation function (Ef) elements (218, 220)
operate separately during each ciphering round eliminating an XOR
operation from the critical path.