A universally available, public cryptographic control unit (crypto unit) is used in a cryptographic system shared by multiple independent users. The crypto unit, which is installed as a peripheral device to a general-purpose computer, loads and unloads encrypted security applets into an onboard RAM memory...http://www.google.com/patents/US6449720?utm_source=gb-gplus-sharePatent US6449720 - Public cryptographic control unit and system therefor
