Private Address Being Shown When Using Mobile Data to Connect to Video Conference

[NeilCotton]

Good evening all,

I am using vodafone connected mobile devices to try and connect to video conference systems, however, the conference unit recieves the call, however it sees it coming from the phones private address (allocated by Vodafone), and not the public address. This means the the data SENT by the phone is RECEIVED by the video conference unit, however the data FROM the video conference unit can not be routed back to the phone, as it only see's it's PRIVATE address (10.x.x.x), which is not routable back out over the private internet.

This conference system doesn't have the same problem on 3 or O2, and works to any other publically accessible systems. Also, I have tried multiple vodafone devices connecting to multiple video conference systems in multiple configurations, and somehow, the endpoint only ever sees the data coming from the private address.

This must be something to do with Vodafone's NATing policy, however, I can't even figure out how that is possible.

Anything you can suggest to help would be wonderful.

[ChazzD]

@NeilCotton

Please speak with our Broadband team so they can help further with this. 

[NeilCotton]

@ChazzD

Thanks for the direction, however, I'm afraid that link does not work. Is there a direct contact for talking to the technical network team about this issue?

Regards

Neil

[SimpleTruth]

Hi Neil,

Vodafone use something called "Carrier-Grade NAT" for nearly all their mobile data connections. This is effectively a form of double NAT. In other words you will only ever get a "private" ip address on your mobile data connection. Please see this Wkipedia link.

https://en.wikipedia.org/wiki/Carrier-grade_NAT

Regards,

SimpleTruth

[NeilCotton]

Would this mean that the end point (inside my network) would see this "private" address as the source?

[SimpleTruth]

If you are using your phone to connect to the video conferencing server, over Vodafone's mobile data network, then it will most likely have a 10.x.x.x network address. This is known as a private, non routable, address. Depending how an application works it may be a requirement that you have a public routable address allocated to your phone. Applications that initiate a network connection to your phone will be broken when using NAT. You can check what public IP address Vodafone is using if you just google "check my ip" from the browser on your phone. You will see that it's not the 10.x.x.x that's allocated to your phone.

Your best idea is to contact the video conferencing provider and explain that your service provider uses NAT (CGN) and ask them if they have a solution. They might be able to suggest or provide a VPN type service to solve the problem.