IPV6 6to4 tunnels

A IPV6 tunnelling method that can be used in a one to many environment (as opposed to point to point tunnelling). To configure it all that's required is
1) a tunnel interface given a special IPV6 address with an embedded IPV4 interface address.
2002:{first 2 octects ipv4 address}:{second 2 octects of ipv4 address}:...
2) an ipv6 static route '2002::/16 tu0'

The CISCO IOS works its magic to nail up connectivity to the other tunnel end points.

interface Tunnel0
no ip address
no ip redirects
ipv6 address 2002:101:101:134::1/64
tunnel source Loopback0
tunnel mode ipv6ip 6to4

interface Loopback0
ip address 1.1.1.1 255.255.255.0
!
ipv6 route 2002::/16 Tunnel0

interface Loopback1
no ip address
ipv6 address 2002:1::1/64


All thats required to connect IPV6 address spaces over the tunnel is to implement IPV6 routing over the tunnel

e.g.

R1
ipv6 route 2002:3::/64 2002:303:303:134::3

Router_1#PING 2002:3::3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 2002:3::3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 44/97/152 ms
Router_1#