IVI Translation refers to a stateless IPv4/IPv6 translation technique. It allows hosts in different address families (IPv4 and IPv6) communicate with each other and keeps the end-to-end address transparency.
Stateless NAT64 can be used in 4 different scenarios:
Address translation defined in RFC 6052 is a stateless mapping scheme, which embeds IPv4 address in network specific IPv6 prefix and forms IPv4-converted and IPv4-translatable addresses. The IPv4-converted IPv6 addresses are the IPv6 addresses used to represent IPv4 nodes in an IPv6 network. The IPv4-translatable IPv6 addresses are the IPv6 addresses assigned to IPv6 nodes for use with stateless translation.
Header translation and ICMP translation defined in RFC 6145 are algorithms to perform header translation between IPv4 and IPv6, as well as between ICMP and ICMPv6.
Address sharing stateless NAT64 enables multiple IPv6 nodes sharing a single public IPv4 address, with each node managing a different range of ports. This can be achieved by defining suffix of the address format RFC 6052.
Dual stateless translation is also called dIVI Translation. Due to the stateless nature, after the second translation, the original IPv4 address can be restored. The advantage of stateless NAT464 is that the DNS64 and application-level gateway (ALG) are not needed.
The stateless NAT64 also forms the basic building blocks for stateful NAT64. Additional building block is the maintaining of the translation states defined in RFC 6146.
Relation to Stateless NAT464 (dIVI, dIVI-PD)
Due to stateless nature, the second stateless translator can be introduced to translate the IPv4-translatable IPv6 address back to IPv4. In this case, the DNS64 and ALG are not required. See dIVI Translation