An X509 certificate is used in public key infrastructures as the standard used by all organizations for providing security to electronic information. The standard was created as a means to allow different computers to be able to talk to one another without having to worry about certificate compatibility issues. The X509 standards also outline the formats used for other types of certificates and public keys.
An X509 Certificate Contains Many Different Parts
The standards create by an X509 certificate contains many different parts to make up the entire certificate. Within the certificate such information as the version number, issuers, certificate serial number, public key information, and time valid is contained. There are also optional components which can be included in the certificate, and are up to the issuer to decide if these components are required. The certificate can be signed or unsigned depending upon whether it is a public certificate or private certificate.