NAT64 is a mechanism for translating IPv6 packets to IPv4 packets, and vice versa. NAT64 allows IPv6-only clients to contact IPv4 servers using unicast UDP or TCP. NAT64 only allows an IPv6-only client to initiate communications to an IPv4-only server. To perform IPv6-to-IPv4 translation, binding and session information is saved. NAT64 is stateful. alaskasworld