What Is a Tunnel Adapter?

By Iam Jaebi

Tunnel adapters help bridge communication between IPv4 and IPv6 networks.
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In computer networking, tunneling is a strategy of sending data across a network by piggybacking off of another network's connections. Tunneling makes it possible for someone to send secure or private data across an open network such as the Internet. Windows operating system uses tunnel adapters as part of the networking interface, which allows the computer to communicate with IPv4 and IPv6 networks. To understand how tunnel adapters work and why they are needed, it's important to understand the structure of networks and the Internet.

IP Addressing

IP addressing is an established method created to connect one computer to any other computer across a network (interconnected computers and routing devices). When a computer is added to a network, a networking device or the user assigned the computer an IP address, which takes the form of "" Like with a home address, any information intended for a specific IP address is delivered to the computer associated with that number.


IPv4, or Internet Protocol version 4 is the worldwide standard for assigning computers an IP address on the Internet, with the form "192.168.564.10." This standard provides 32-bit numbers, which can be combined in more than 4 billion ways. This gives the Internet the capacity to have as many unique IP addresses online at one time. In early 2011, the capacity of the IPv4 standard to uniquely identify computers on the Internet was surpassed by the demand for IP addresses.


IPv6, or Internet Protocol version 6, is a next generation standard for uniquely identifying computers on the Internet. IPv6 uses 128-bit addresses, which have the capacity to provide unique IP addresses for far more computers than the IPv4 standard. While IPv6 has been developed and tested over a number of years, it is not directly compatible with the IPv4 standard. This also means IPv6 is not compatible with the computers, routers and other network devices based off of the IPv4 standard.

Tunnel Adapters

The Internet industry must adapt the higher capacity standard of IPv6 to meet the demand of world Internet usage. Software developers such as Microsoft have begun to make the transition from IPv4 to IPv6. The networking utilities in newer versions of the Windows operating system uses "Automatic Tunneling Pseudo-Interface," which allows IPv6 communication to transmit across IPv4 networks.The pseudo interface automatically creates tunnels, or methods for IPv6 network data to transmit over IPv4 data. Tunnel adapters are IPv6-transition technologies used to encapsulate data designed for the Version 6 standard and transmit it across IPv4 networks and devices.