Subject Alternative Name (SAN) is an extension to X.509 that allows various values to be associated with a security certificate using a subjectAltName field. These values are called Subject Alternative Names (SANs). Names include:
- Email addresses
- IP addresses
- URIs
- DNS names (this is usually also provided as the Common Name RDN within the Subject field of the main certificate.)
- directory names (alternative Distinguished Names to that given in the Subject)
- other names, given as a General Name: a registered object identifier followed by a value