This document specifies a new Dynamic Host Configuration Protocol for IPv6 (DHCPv6) option that can be used to exchange information about a DHCPv6 client's Fully Qualified Domain Name (FQDN) and about responsibility for updating DNS resource records (RRs) related to the client's address assignments.
RFC 4704-2006 history
2006RFC 4704-2006 The Dynamic Host Configuration Protocol for IPv6 (DHCPv6) Client Fully Qualified Domain Name (FQDN) Option