"Recommendation ITU-T Y.2051 defines a new term@ ""IPv6-based NGN""@ to support advanced architectural objectives of the next generation network (NGN) by using IPv6 protocols and mechanisms. Recommendation ITU-T Y.2015 describes general requirements for identifier and locator separation (also known as ID/LOC separation) to efficiently support mobility@ multihoming and host renumbering in the NGN. In order to enrich the IPv6-based NGN with the benefits of ID/locator separation@ this Recommendation describes a framework of ID/LOC separation in the IPv6-based NGN. The scope of this Recommendation includes: ?C IPv6 addressing schemes for ID/LOC separation ?C mapping functions and procedures for ID/LOC separation in IPv6-based NGNs ?C considerations of deployment for ID/LOC separation in IPv6-based NGNs."