UC3M The IPv6 Company This document specifies a stateful NAT64 translation, which allows IPv6-Only clients to contact IPv4 servers using unicast UDP, TCP, or ICMP. One or more public IPv4 addresses assigned to a stateful NAT64 translator are shared among several IPv6-Only clients. Stateful NAT64 translation also supports IPv4-initiated communications to a subset of the IPv6 hosts through statically configured bindings in the stateful NAT64 translator. When the stateful NAT64 translation is used in conjunction with DNS64, no changes are required in either the IPv6 client or the IPv4 server. This document obsoletes RFC 6146.