As we migrate from IPv4 to IPv6, we’ll need ways to transport our multiple IP types through many different networks. In this video, you’ll learn about 6to4, 4in6, dual-stack IP configurations, Teredo, and Miredo networking.
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As you might imagine, integrating an IPv6 network into an existing IPv4 network isn’t something where you can simply flip a switch and everything is working. In many cases, we have to find ways to work around places where IPv6 has not been completely implemented so that we can pass IPv6 from one side of the network to the other. If you’re on a network that can support both IPv4 and IPv6 simultaneously from end to end, you simply need to add both of those protocols onto your computer. This is called a dual stack configuration, and it’s very common to have both IPv4 and IPv6 on the exact same network interface.
With 6 to 4 addressing, you take your existing IP address and you modify it to turn it into an IPv6 address and then send that information through a relay router. Usually, we’ll add a 2002 to the beginning of a 6 to 4 address and then the rest of the address is modified based on your IP addresses. It sends this information into the relay routers using IP protocol 41. This is intended to be a transition between IPv4 and IPv6. Ideally, you would have IPv6 run natively all the way through your network. So it’s expected that this would be a temporary measure.
One important consideration for 6 to 4 is that you can only be used on public IP addresses or where you’re not performing any network address translation. And since a lot of our networks take advantage of NAT, the 6 to 4 addressing can really only be used in very specific circumstances. Another tunneling protocol you might run into is when you have a native IPv6 network and you need to get IPv4 sent from one end to the other. That technology is called 4 in 6.
Now since we probably have most of our networks already running IPv4, you’re probably not going to run into a scenario were 4 in 6 is going to help you. But if there are some native IPv6 networks that you need to tunnel IPv4 through, you might be able to take advantage of 4 in 6. Another way to get IPv6 sent through our network, even if there’s IPv4 in the middle, is to use a transitioning method called Teredo. This allows us to tunnel the information through that IPv4 network, even if the IPv4 network is also performing network address translation.
We don’t need any special IPv6 routers. There’s no special relays to use, and we can simply use this Teredo capability inside of our operating system to send that information across the network. Ideally, this is something that will be used temporarily. Ultimately, we’ll have native capabilities to send IPv6 from one end to the other, and we won’t need to tunnel inside of IPv4. We commonly see to Teredo running in a Windows operating system, but there’s an open source alternative called Miredo. With Miredo, we can use the same Teredo tunneling on a Linux, a Unix, or a Mac OS computer.