China Telecom China Telecom This document defines a new Domain Name System (DNS) resource record type called the Address Mapping Record (AMR). The AMR record enables querying of IPv6 mapping prefixes associated with the destination address of an IPv4 packet in IPv6-only networks. This mechanism facilities the transmission of IPv4 service data across multi-domain in IPv6-only environment, supporting IPv4-as-a-Service (IPv4aaS) implementations.