Z1 CertServer (formerly Z1 Backbone Of Trust CertServer) is a server-based software solution for the storage and administration of X.509 certificates and OpenPGP keys. It targets customers who use a public key infrastructure (based on X.509 or OpenPGP) and who want to take advantage of the central access to certificates. It also automatically validates certificates by querying certificate revocation lists (CRLs) from the issuing trust centers, or by using OCSP (Online Certificate Status Protocol). Java and C/C++ SDKs are provided. It is available as pre-installed hardware or a virtual appliance, with evaluation packages for Debian and Solaris.