on 19-04-2013 14h49
SO 2 weeks ago port forwarding stopped working as per the thread i started earlier here:
I've started a new thread so i can ask the clear question...are BT now using CGNAT? I've been looking but have been unable to find anything and the tech support I have spoken to don't seem to have any idea what it is.
on 19-04-2013 18h33
Its certainly possible. As im sure your aware, IPv4 addresses are in short supply probably costly, so this is a way arround it for them i supose.
But as you found, it can cause issues with services that rely on your public IP address, UPNP and port mapping.
I would of thought if they are doing this it would be better to offer a cheaper service or brand as "security firewall service" (since it essentially will block most incoming traffic), as a seperate plan to avoid causing problems to users that need a public IP address.
Also I will check my details when I get home after a hub reboot to see if I get allocated this range.
The other possibility is that they can control the allocation by account basis or perhaps they dish out this new 100 range when they run out of IP addresses from the pool, kinda fallback protection depending on how many users have their hubs turned on if you know what I mean.
on 19-04-2013 18h52
Well, i've checked with colleagues on infinity and their routers all give the same WAN address as what is reported by whatismyip.com meaning i'm the only one I know of on a shared address.
I'm having a nightmare trying to get through to somebody who can help me with this. I prefered traffic shaping to this
on 19-04-2013 19h04
This does seem to be incorrect in your case.
If you would like to contact one of the UK based BT Care Team who moderate this forum, they should be able to help you.
They can be contacted using this link BT Care Team
They normally respond by phone or e-mail, within three working days, however you should get an immediate confirmation, with a tracking number.
on 19-04-2013 19h10
Thanks i'll give them a try, the normal helpdesk just doesn't seem to be geared up for these kind of issues...though to be honest I did expect to struggle its not exactly the kind of issue they are going to be dealing with often I don't think
on 19-04-2013 19h14
It could be a mis-configuration somewhere on the Infinity node. It only mobile broadband operators that tend to use CGNAT, to save on IP addresses, it would not make sense for BT to use it.
That makes it impossible to forward incoming ports to a specific mobile device.
on 19-04-2013 19h24
Yea i've searched the internet and I can't find any mention of anybody using it yet other than plusnet who are trialing it, and they asked for people to test it before applying it so maybe it is a mistake.
on 26-05-2013 19h53
on 26-05-2013 19h57
Here is a faq on CGNAT http://btsupport.custhelp.com/app/answers/detail/a
on 26-05-2013 20h14