The IPv6 tunnel is a IPV6 message encapsulated in the IPV4 message, allowing IPV6 packets to communicate through the IPV4 network. For equipment adopting tunnel technology, the source and destination address of the IPV6 datagram is encapsulated into the IPV4,IPV4 message at the entrance of the tunnel, respectively, the IPV4 address of the tunnel entrance and the tunnel exit, and the IPV6 message is forwarded to the destination node at the exit of the tunnel. Tunnel technology only requires modifications at the entrances and exits of tunnels and is not required for other parts and is easy to achieve. However, tunneling technology cannot realize direct communication between IPV4 host and IPV6 host.
The main difference between configuring tunnels and automatic tunnels is that automatic tunneling is possible only if the IPV6 address of the node performing the tunneling function is a IPV4 compatible address. When an I-P address is established for a node that performs a tunnel function, the Automatic tunneling method does not need to be configured, while the configuration tunneling method requires that the tunnel end node use other mechanisms to obtain its IPV4 address, for example, using D H C P, manual configuration, or other IPV4 configuration mechanism.
If you are using a notebook, often debug the network. WINDOWS 7 will spontaneously build a IPV6 tunnel, usually we use Ipconfig/all will see a lot of tunnels, such as my side has more than 40 tunnels, want to see IPv4 information, will flash over, to use to bring inconvenience. This is because Windows requires the use of one or more IPv6 transition technologies during the IPV6 migration process. We can manually close the IPv6 tunnel.
We only use the following 3 commands to close the IPv6 interface
netsh interface teredo set state disable
netsh interface 6to4 set state disabled
netsh interface isatap set state disabled
To restore the IPv6 tunnel, use the following command:
netsh interface teredo set state default
netsh interface 6to4 set state default
netsh interface isatap set state default