IPv4-compatible address
From Wikipedia, the free encyclopedia
IPv4-compatible IPv6 addresses constitute a special class of IPv6 addresses. Such an IPv6 address has its first 96 bits set to zero, while its last 32 bits represents an IPv4 address.
IPv6 transition mechanisms no longer use IPv4-compatible addresses. The only remaining use of these addresses is to represent an IPv4 address in a table with fixed size members that must also be able to store an IPv6 address.
The undefined IPv6 address :: and the loopback IPv6 address ::1 are not really IPv4-compatible addresses, even though they are included in the IPv6 address space ::/96.
