by Zdeněk Říha, December 1998, 43 pages.
FIMU-RS-98-07. Available as Postscript, PDF.
Certifications are specific procedures which compare references with measurements that allow a party to bind an attribute to an unknown party. There are three main types of methods that have been proposed to deal with this concern: directory methods, based on Certification Authorities: X.509 (e.g. SSL, PKIX), referral methods, based on "introducers" of keys (e.g. PGP), and collaborative methods (e.g. SKIP). All of them are described in the report.