Method and Apparatus For Computing A Shared Secret Key

• US 20130016831A1
• Filed: 09/14/2012
• Published: 01/17/2013
• Est. Priority Date: 12/31/2001
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Certicom Corporation (Blackberry Limited)
• Inventors: Lambert, Robert, Vadekar, Ashok
• Granted Patent: US 8,693,684 B2
• Time in Patent Office: Days
• US Class Current: 380/30
• CPC Class Codes: H04L 9/0844 with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys

Abstract

A method of generating a key by a first correspondent. The key is computable by a second correspondent by a second correspondent. The method comprising the steps of:

• • a) making available to the second correspondent a first short term public key;
  • b) obtaining a second short term public key from the second correspondent;
  • c) computing a first exponent derived from the first short term private key, the first short term public key, and said first long term private key;
  • d) computing a second exponent derived from the first short term private key, the first long term public key, the second short term public key and the first long term private key;
    computing a simultaneous exponentiation of the first exponent with the second short term public key and said second exponent with the second long term public key.

Claims

1. A method of generating a key by a first correspondent, wherein said key is computable by a second correspondent, said method comprising the steps of:

a) making available to said second correspondent a first short term public key;

b) obtaining a second short term public key from said second correspondent;

c) computing a first exponent derived from said first short term private key, said first short term public key, and said first long term private key;

d) computing a second exponent derived from said first short term private key, said first long term public key, said second short term public key and said first long term private key;

computing a simultaneous exponentiation of said first exponent with said second short term public key and said second exponent with said second long term public key.