Patent ID: 6246771
Filing Date: 2001-06-12
Classification: H04L

Abstract:
A key recovery system by which a key recovery agent recovers a session key used to encrypt a message, comprising:means for the key recovery agent to replay a recorded communication between the sender of the message and an authentication server, said session key having been generated with assistance of said authentication server during said communication;means for the key recovery agent to request the authentication server to assist in recovering the session key for use by the key recovery agent to decrypt said message, said authentication server thereupon recovering the session key from said recorded communication by recreating a process by which the session key was originally generated utilizing secret information accessible only by the authentication server;means for the authentication server to authenticate said request by the key recovery agent to assist in recovering the session key; andmeans for transmitting said session key from the authentication server to the key recovery agent in order to decrypt said message.