http://www.rfc-editor.org/rfc/rfc4985.txt
RFC 4985: Internet X.509 Public Key Infrastructure Subject Alternative Name for Expression of Service Name, S. Santesson2007-08-01T23:00:00-00:00This document defines a new name form for inclusion in the otherName field of an X.509 Subject Alternative Name extension that allows a certificate subject to be associated with the service name and domain name components of a DNS Service Resource Record. [STANDARDS-TRACK]