Application for Personal Key Crypto with Insecure Terminals
Original Publication Date: 1981-Jun-01
Included in the Prior Art Database: 2005-Feb-11
A method is disclosed for secure data transmissions between an inexpensive terminal equipped with a crypto facility, the design of which does not provide adequate protection for a resident master key, and a host processor equipped with a secure crypto facility. The method is based upon a secret pseudo-master key defined as a personal key generating key (KPG) residing in protected form at the host system and used to produce any user personal key (KP) on demand, thereby eliminating the need to store a substantial directory of personal keys at the host system. Once the participants in the communication have a copy of KP, in a form usable at their respective crypto facilities, each may then send and receive messages enciphered under KP.