Dual Control of Equipment Master Keys
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Jan-31
This article describes a solution to the problem that an equipment master key must be known to a key distributer in order to generate useful enciphered keys for presentation on the key input bus. An equipment master key is a cryptographic key held in a secure module for the purpose of eciphering other keys. The secure module contains means for performing cryptographic functions, the cryptographic keys to be used in performing these functions are held in insecure storage outside of the secure module enciphered under the equipment master key (or a variant thereof). The enciphered keys are passed to the secure module together with the data required to perform a given function. The secure module uses a means of decipherment to produce a working key from the enciphered value presented at its enciphered key input.