Patent ID: 6212281
Filing Date: 2001-04-03
Classification: H04L

Abstract:
A digital signature protocol for authenticating digital information transmitted by one correspondent to another over a data communication system, at least said one correspondent having long-term private key and corresponding long-term public key associated therewith, said protocol comprising the steps of said one correspondent generating a short term public key from an integer k, encrypting a message m containing said information with an encryption key derived from said short term public key, to provide a ciphertext e of said message, applying a hash function to said ciphertext to provide a hash e', generating a signature component, s, incorporating said hash e', said long-term public key and said integer k, forwarding a signature pair including said ciphertext e and said component s to said other correspondent, hashing said ciphertext e received by said other correspondent with said hash function to obtain a received hash e'*, using said received hash e'*, and said long-term public key to recover said encryption key from said signature component, and retrieving said message m from said ciphertext e by application of said encryption key recovered from said signature component.