How to get IPv6 with a TP-Link C50 Router on BT
I’m using the TP-Link Archer C50 AC1200 with an Openreach modem in this tutorial. However, it should apply to similar TP-Link routers who by default cannot connect to BT’s IPv6.
The main issue with using the TP-Link Router to connect to BT’s IPv6 is that it won’t connect using TP-Link’s default settings and according to some BT forum posts it’s due to how TP-Link uses the /64 prefix for IPv6 when the BT uses /56 prefix for IP addresses and there’s no real way to change it.[1]
This is a workaround to get the router to connect to BT’s IPv6 services and may or may not work based on your setup.
First, you have to update to the latest firmware from TP-Link which you can find here. After updating your firmware, navigate to the TP-Link administrator panel (typically on 192.168.0.1) and log in with your login credentials, if you don’t know them and you know you haven’t changed it the default username is admin and the password is also admin though you should get that changed ASAP. After logging in click on the IPv6 button on the panel on the left-hand side.
Then click on IPv6 WAN and change your settings as seen below.
You can choose to re-enter your BT broadband username and password here, but you can choose to use the same PPPoE session as your IPv4 connection which will do that for you. At this point I would recommend not using BT’s DNS services as at the time of me writing this, BT still doesn’t index IPv6 sites. But please note that not using BT’s DNS will deactivate the parental controls/web filtering that you have on your BT account.
The DNS servers I would recommend using are Cloudflare’s DNS or Google’s DNS and their IPv4 and IPv6 addresses are as follows:
Cloudflare:
1.1.1.1 and 1.0.0.1 for IPv4
2606:4700:4700::1111 and 2606:4700:4700:1001 for IPv6
Google:
8.8.8.8 and 8.8.4.4 for IPv4
2001:4860:4860::8888 and 2001:4860:4860::8844 for IPv6
That should be it! Reboot your router and then go to test-ipv6.com or ipv6.google.com on your PC to test to see if IPv6 is working, Android devices don’t seem to like to connect to IPv6 as of the Android Q Beta.
There’s also a small glitch where the router would say that it’s still connecting to IPv6 but as long you can see that it has a gateway IP and can access ipv6.google.com, you should be fine.
Edit: After running this setup for a while, I’ve discovered that sometimes, the C50 was unable to get an IPv6 address after a reboot. This can be fixed by toggling the MLD Proxy option off and back on again.
[1] https://community.bt.com/t5/Home-setup-Wi-Fi-network/IPv6-on-Tp-Link-TD-W9980/td-p/1672827
