METHOD OF ESTABLISHING SECURE COMMUNICATIONS IN A DIGITAL NETWORK USING PSEUDONYMIC DIGITAL IDENTIFIERS

A system and method of relating a public key to a compact identification string in a digital certificate to enable an entity to construct a certificate chain from a root certificate authority to an end-entity efficiently and further allow a certificate holder to store only its identifier, thus providing privacy protection, and present this in place of a digital certificate for authentication rather than storing and presenting its certificate or a chain of certificates representing the certificate path up to the root certificate authority. In a preferred embodiment, the certificate authority generates unique identifier for each certificate consisting its pseudonym concatenated with the pseudonyms of other sub-certificate authorities in the certificate chain between it and the certificate holder, concatenated with certificate holder's pseudonym. The pseudonyms are generated by the entity known by the pseudonym or the entity certifying a binding between the pseudonym and the entity's public key.