(19) United States
(12) Patent Application Publication (io) Pub. No.: US 2004/0158708 Al
Peyravian et al. (43) Pub. Date: Aug. 12,2004
(54) METHOD FOR DISTRIBUTING AND
AUTHENTICATING PUBLIC KEYS USING
TIME ORDERED EXCHANGES
(75) Inventors: Mohammad Peyravian, Morrisville,
NC (US); Allen Leonid Roginsky,
Durham, NC (US); Nevenko Zunic,
Hopewell Junction, NY (US)
Correspondence Address:
IBM CORPORATION
IPLAW IQOA/40-3
1701 NORTH STREET
ENDICOTT, NY 13760 (US)
(73) Assignee: International Business Machines Corporation, Armonk, NY
(21) Appl. No.: 10/361,515
(22) Filed: Feb. 10, 2003
Publication Classification
(51) Int. CI.7 11041. 9/00
(52) U.S. CI 713/156; 713/176
(57) ABSTRACT
A method to exchange and authenticate public cryptographic keys between parties that share a common but secret password. The parties exchange public keys, where the public keys are accompanied by hashed values based on the keys, the password, and random numbers. Each party then encrypts its random number using the public key ol the other party, and the encryptions are exchanged. Based on the received encryptions and the known password, each party then re-computes the hashed value received from the other party, and compares the re-computed hashed value with the received hashed value. If the two are the same, the public key that accompanied the hashed value is judged authentic.
