The MDC calculations use this notation:

eK(X)

Denotes DES encryption of plaintext X using key K

||

Denotes the concatenation operation

XOR

Denotes the exclusive-OR operation

:=

Denotes the assignment operation

T8<1>

Denotes the first 8–byte block of text

T8<2>

Denotes the second 8–byte block of text, and so on

KD1, KD2, IN1, IN2, OUT1, OUT2

Denote 64–bit quantities