Patent ID: 7958362
Filing Date: 2011-06-07
Classification: H04L

Abstract:
1. A method for user authentication based on asymmetric cryptography, comprising: providing a first input and a second input from a user who requests an access to a computer system; authorizing the access by using a challenge and response process when the first input matches a personalized secret and the second input matches a crypto-key authenticator comprising a public modulus, a public exponent, and a private-key-dependent exponent; changing the personalized secret to a new secret and updating the private-key-dependent exponent while keeping the public modulus and the public exponent unchanged; using the personalized secret and two odd primes in a crypto-key generation process to produce the public modulus, public exponent, and private-key-dependent exponent; and registering said user's public key comprising said public modulus and said public exponent with said computer system, acceptance of which signifies an agreement between said user and said computer system in resolving dispute; wherein the personalized secret comprises a user-chosen password, and the challenge and response process comprises using the first and second inputs to produce a digital signature in response to a challenge from the computer system by verifying the digital signature on both a user site and a system site.