Want to learn what a Teredo IP address is, or want to find out why you can’t get a Teredo IP address on your Xbox One?
We’ll tell you everything you need to know about that in easy-to-understand terms.
First Things First – What Is Teredo?
Teredo is a tunneling protocol that allows communication between IPv4 and IPv6 networks. Basically, it makes communications between IPv4 connections and IPv6 addresses possible by encapsulating IPv6 datagram packets within IPv4 UDP packets.
Not sure what IPv4 and IPv6 are? Well, IPv4 is the standard 32-bit IP address format (220.127.116.11), while IPv6 is the 128-bit successor to IPv4 (can look something like this “ 2002:0db7:0000:0000:0000:ff00:0067:7329”).
And it seems that we’re officially out of IPv4 addresses. IPv6 has been deployed worldwide continuously over the past years to deal with that problem, but there’s still one issue – IPv4 and IPv6 can’t communicate directly because they’re completely different protocols with incompatible addressing and packet headers.
Dual-stack networks solve that problem by making both protocols run in tandem over shared or dedicated links. However, not all ISP infrastructure can handle that upgrade yet.
So, an alternative is used to translate IPv4 to IPv6 and vice-versa: 6to4, 6over4, 6rd, or Teredo.
Teredo is built into most Windows devices, and is on by default on Windows 10. It’s usually considered a temporary solution until full IPv6 native connectivity is achieved.
How Does Teredo Work?
- First, a Teredo client communicates with a Teredo server to configure the tunnel. The server supports IPv4 connectivity and can outfit Teredo clients with IPv6 connectivity.
- Next, the server determines the location of the client (what type of NAT they are behind).
- After that, the Teredo IP address embeds the address and port through which the client will receive the IPv4 UDP packets that encapsulate the IPv6 datagram packets.
- Then, the Teredo client will use Teredo relays (routers, basically) to exchange IPv6 packets with other IPv6 servers. The relay will handle the encapsulation and decapsulation process.
What Is a Teredo IP Address?
The Teredo IP address bridges the gap between IPv4 and IPv6 addresses, acting as a transition technology between the two. Thanks to it, IPv6 data can be successfully transferred to IPv4 networks.
A Teredo IP address is normally an IPv6 address. It’s slightly different, though, because it’s obtained by combining a Teredo IPv6 client prefix and a Teredo node identifier.
The client prefix is normally 2001:0000 (32-bit), and the 64-bit node identifier contains:
- The UDP port and IPv4 address the Teredo client can be reached at.
- A flag that indicates what type of NAT the client uses to access the IPv4 Internet.
Here’s an example of a Teredo IP address: 2001:0000:4136:E378:8000:63BF:3FFF:FDD2.
Teredo Is Unable to Qualify
A lot of our readers told us about this error message, and we also saw many people on Reddit complaining about this issue. It seems that this problem only occurs on the Xbox One gaming console.
You’ll very likely see this message if you can’t host or join an Xbox Live multiplayer game, or if you can’t connect to a party chat session.
To check if you’re dealing with this problem, hit the Start button, and go to Settings > Gaming > Xbox Networking. Under Xbox Live multiplayer, look for NAT Type and see if it says Teredo is unable to qualify.
If it does, that means you can’t get a Teredo IP address through your PC.
Why does that happen? Here are some possibilities:
- A device on your network is blocking the Teredo protocol.
- You have software on your PC that disables Teredo functionality.
- Your Teredo adapter is experiencing problems.
How to Fix This Issue
The first thing you should do is head over to Microsoft’s support article for this problem. They have a list of things you can try.
According to their recommendations, you should try their tips in order. But according to some users on Reddit, steps #5 and #6 are what solved their problems.
If that doesn’t work or you want to try something else, here’s what else people said worked:
- Change the DNS to Google Public DNS:
- 18.104.22.168 and 22.214.171.124 (IPv4 addresses)
- 2001:4860:4860::8888 and 2001:4860:4860::8844 (IPv6 addresses)
- If you have an Ethernet connection, unplug it for a few seconds.
- Check if IPv6 is enabled on your PC. On Windows 10, right-click the Network/Wi-Fi icon, and go to Open Network & Internet settings > Change adapter options, double-click the network adapter and click Properties. If Internet Protocol Version 6 (TCP/IPv6) is unchecked, enable it.
- Enable UPnP on your router. That varies from router to router, so check your manual or the manufacturer’s website.
- Check if your router has an option to allow Teredo tunnels under the IPv6 section. If it does and it’s not enabled, turn it on.
- Open the following ports on your router:
- Port 88 (UDP)
- Port 3074 (UDP and TCP)
- Port 53 (UDP and TCP)
- Port 80 (TCP)
- Port 500 (UDP)
- UDP Port 3544 (UDP)
- UDP Port 4500 (UDP)
- Clear the Alternate MAC Address (Settings > Network > Advanced settings > Alternate MAC Address > Clear).
- If you use a VPN that disables Teredo, disconnect from the server. If that doesn’t work, uninstall the VPN’s network adapter.
- Do a factory reset of your console.
Can Teredo Cause VPN Leaks?
Yes, it actually can.
Because Teredo is a tunneling protocol, it can actually bypass the VPN tunnel. That means any DNS requests you make through IPv6 won’t go through the VPN connection, but the Teredo connection.
So your ISP could see your browsing even if you use a VPN. Hackers could also try to use that vulnerability to target you with MITM attacks.
How to Test Your VPN for Leaks
It’s pretty simple. Just follow these steps:
- While disconnected from the VPN, use the ipleak.net tool.
- Take a screenshot of the results. You’ll see your real IP and DNS addresses there.
- Connect to the VPN, and access the site again.
- Compare the new results with the ones from the previous screenshot. If you still see your original IP or DNS address, your VPN is leaking.
How to Fix VPN Leaks Caused by Teredo
There are two things you can do:
1. Disable Teredo
Since Teredo is causing this problem, you should obviously disable it. The good news is doing that is pretty simple.
First, we’ll need the command prompt. Open the Start menu and type cmd. Then, right-click Command Prompt and hit Run as Administrator. Doing that brings up the elevated command prompt, and you need that to successfully disable Teredo.
Now, just type this: netsh interface teredo set state disabled. If the prompt replies with OK, congrats – you disabled Teredo.
If you want to re-enable Teredo, just type netsh interface teredo set state type=default in the command prompt.
2. Use a VPN with Leak Protection
If you don’t want to disable Teredo, you can just get a VPN that offers IPv6 leak protection. Most of the time, that means it disables Teredo functionality (among other things) to prevent IPv6 leaks.
NordVPN, ExpressVPN, and CyberGhost are solid options.
Won’t That Cause the Teredo Is Unable to Qualify Issue?
Yes, that can happen. You’ll disable Teredo or use a VPN that disables its functionality, so it can get in the way of your online gaming on Xbox One.
That’s why you should only do that if you don’t use the console. Or only while you need to do something with a VPN without it leaking (like torrenting a movie).
If you want the best of both worlds, though, you should get a VPN that supports IPv6, like HIDEme or Perfect Privacy. Normally, they won’t disable Teredo because IPv6 doesn’t interfere with their connections.
Know Anything Else about Teredo IP Address?
Go ahead and tell us about it in the comments. Also, if you know other ways to fix the Teredo is unable to qualify problem, please share them with us. If they’re good enough, we’ll include them in the article.