The IP6 tunnel is closed in Windows 7 and the

IPv6 tunnel encapsulates IPv6 packets in IPv4 packets, allowing IPv6 packets to communicate through the IPv4 network. For the tunneling device, the IPv6 datagram is encapsulated into IPv4 at the entrance of the tunnel. The source and destination addresses of the IPv4 packet are the IPv4 address of the tunnel entry and the tunnel exit respectively. At the exit of the tunnel, Then forward the IPv6 packet to the destination node. Tunneling technology only requires modifications at the entrance and exit of the tunnel. It is not required for other parts and is easy to implement. However, tunneling technology cannot achieve direct communication between IPv4 hosts and IPv6 hosts.
The main difference between configuring a tunnel and an automatic tunnel is that automatic tunneling is only possible when the IPv6 address of the node performing the tunnel function is an IPv4-compatible address. The automatic tunneling method does not need to be configured when the IP address is established for the node performing the tunnel function. The tunneling method requires the tunnel end node to use other mechanisms to obtain its IPv4 address, for example, D H C P, manual configuration or other IPv4 configuration mechanism.
If you are using a laptop, often debug the network. WINDOWS 7 will spontaneously establish an IPV6 tunnel. Usually we will see a lot of tunnels with ipconfig /all. For example, I have more than 40 tunnels here. If I want to see IPv4 information, it will flash and pass. inconvenient. This is because windows needs to use one or more IPv6 transition technologies during the IPv6 migration process. We can manually close the IPv6 tunnel.
We can only use the following three commands to close the IPv6 interface.
netsh interface teredo set state disable
netsh interface 6to4 set state disabled
netsh interface isatap set state disabled
If you want To restore an IPv6 tunnel, use the following command:
netsh interface teredo set state default
netsh interface 6to4 set state default
netsh interface isatap set state default