Method for publishing certification information certified by a plurality of authorities and apparatus and portable data storage media used to practice said method

摘要

A method for certifying the public key of a user wishing to communicate using a public key encryption system by a plurality of certifying authorities. A plurality of certifying stations and a user station exchange information and the user station derives a public key from the exchanged information. The certifying stations also publish related information and their public keys. A third party can derive the public key corresponding to the user's private key by operating on the published information with a summation of the certifying station keys.