What does kR denote in IBM cryptography?
I have reviewed documentation preserved by my grandfather, CR Doty. He retained a copyright
https://imgur.com/gallery/ibm-copyright-6493158-UQGHPdP, correspondence with 3 Japanese IBM employees and other IBM artifacts that indicate TOD (IBM) or CTF puzzle.
The materials reference kR ********** where *********** is two words. My analysis of the DES key schedule—starting with a 64-bit master key, applying PC-1 to generate 56 bits, splitting into two 28-bit halves, performing scheduled left shifts, and using PC-2 to produce a 48-bit round key—leads me to suspect that kR may refer to a specific round key.
Can anyone confirm if kR means a round key or if it has another meaning in IBM's cryptographic framework?
-ak
