http://www.rfc-editor.org/rfc/rfc5678.txt
RFC 5678: Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) Options for IEEE 802.21 Mobility Services (MoS) Discovery, G. Bajko, S. Das2009-12-01T23:00:00-00:00This document defines new Dynamic Host Configuration Protocol (DHCPv4 and DHCPv6) options that contain a list of IP addresses and a list of domain names that can be mapped to servers providing IEEE 802.21 type of Mobility Service (MoS) (see RFC 5677). These Mobility Services are used to assist a mobile node (MN) in handover preparation (network discovery) and handover decision (network selection). The services addressed in this document are the Media Independent Handover Services defined in IEEE 802.21. [STANDARDS-TRACK]