Port forwarding on the BT Home Hubs

Latest updates.

Home hub 3 firmware issues.

There has also been a report that a recent firmware update to the HH3B, may have broken the port forwarding facility.
See What have BT done to my system

IP address sharing

BT are implementing CG-NAT for certain Option 1 customers. This will prevent port forwarding from working.
For more information, please visit this link.  IP address translation/sharing

The test that BT suggest, relies on BT keeping their information updated on the databases, and as more
of BTs IP ranges are being shared, this may not be be the case.

Your Broadband IP address as shown on your home hub, must be the same as your public IP address,
otherwise port forwarding will not work, as you would be on CG-NAT.

Here is an example of a CG-NAT address, from one of our forum members.



If the displayed address is in the range 
100.64.0.0 - 100.127.255.255
then you are sharing your IP address with other users.


BT Guide for the Home Hub Port Forwarding with Home Hub

You can check to see if port forwarding is working by using a number of free sites like Canyouseeme

How can I connect to my webcam or NAS if my public IP address changes? 


The home hub 4 and 5 have no reported issues.

There is an example of an IP camera on a HH4 here  Foscam IP camera on HH4

and an example for a NAS on the HH5 Synology NAS


If you are going to manually assign ports, then you must disable
uPnP as that will cause conflicts.

 Please assign a static IP address outside of the home hubs DHCP range, to the device that you are trying to forward to.
You have to do this on the device itself, so read the product manual.


Using the option "always use this IP address" on the home hub, is not the same, and usually fails.

There is a guide to assigning static IP addresses here
Using static IP addresses on your home network

There are also some more examples on this page Hardware menu

When you come to actually assigning the application, make sure that you assign it to the IP address of the device, and not the device name.
The option to do this, is under "user defined", where you are given the option to enter the IP address. You will need to go into the home hub advanced settings to do this.

On the link below, is an worked example of port forwarding on a home hub 2 and 3.
It gives the steps that you need to take to make sure port forwarding works properly. Its for a VPN,
but you can modify the settings to suit your own application or game.

Port Forwarding on the BT Home Hub 2 or 3 and later home hubs.

Main Menu