Tag: Automatic 6to4 Tunnels

Tunneling Technologies: Automatic IPv4 Compatible Tunnels

This kind of tunnel uses IPv4 compatible IPv6 addresses for tunnel interfaces.  These addresses are taken from /96 address comprised of the first 96 bits containing all zeros and the last 32 bits are derived from the IPv4 address.

These addresses are written as:

0:0:0:0:0:0:A.B.C.D or ::A.B.C.D

This is not a scalable solution and this method of addressing is not supported globally, Cisco recommends using ISATAP tunnels instead when considering this kind of solution..