Does Gigafast via Cityfibre use CGNAT

[ThomasBam]

Hi, I’m wondering if anyone can help. Does Sky use CG-NAT or any other technologies that would prevent me from port forwarding, specifically on the Gigafast package using CityFibre’s infrastructure? - Also is it possible to use my own router as I currently use a ubiquiti UCG Ultra and wish to continue using it if at all possible.

[TimmyBGood]

@ThomasBam 

I'm afraid that Sky Broadband over CityFibre infrastructure is too new and too limited in user distribution for there to have been any posts on those topics.

[ThomasBam]

I contacted support and was told this regarding CG-NAT:

"Sky’s Gigafast service uses CityFibre’s FTTP infrastructure and assigns users a dynamic IPv4 address without Carrier-Grade NAT (CG‑NAT)

This means you receive a unique public IPv4 address, making port forwarding feasible in principle."

For the router I was told this:

"When you place your Sky Broadband order, the system will automatically send out a Sky router as

part of the setup process. However, once your service is up and running, you are welcome to use your own

router . To do this, we recommend contacting the Sky Broadband and Technical Team on _____, and

they’ll be happy to guide you through the necessary steps to get your own equipment set up correctly"

So that answers my question - Ill update this post once i'm all set up and detail any issues if I have any but looks promising thus far.

[TimmyBGood]

@ThomasBam 

I'd take that second point with a hefty dose of NaCl: Sky support have historically never provided help with using non-Sky routers.

[JimM1]

@ThomasBam What sky hub do you currently have in use on the City Fibre network?

[ThomasBam]

I've not received my sky gear yet. I'll be set up next month on the 9th and I'll update the post then. I'm hoping after the initial setup with the sky router I can just plug my unifi gear into the ONT but we'll see.

[JimM1]

@ThomasBam Was a OP post the other day someone put there own router on no issue's was only a couple day's ago, also a posting glimpse sure off the new super fast CF router web manager interface, and sure i saw it Map-T assigned but that i cannot see/find anymore! 

[KillerCars]

I am on a Cityfibre based package and can port forward no problem, though I had to configure it via the MySky app.

I am on Gigafast+ with the white cylindrical router, so you will likely get a different Sky router for Gigafast. Either way, the service itself doesn't have limitations on port forwarding in my experience.

Would be interested to know how you get on with using your Unifi gear.

[ThomasBam]

Hey! Had my install today and everything went really smoothly. The engineer installed a new ONT box and connected the Sky router. As soon as he left though I swapped it out for my UniFi router and the internet came straight back up without any issues.

Port forwarding is working perfectly too, looks like it’s plug and play, which is nice.

My UniFi gear was already configured for IPv4 Option 60 and IPv6 Prefix Delegation Size 48, just in case that makes any difference.

It also seems that I’ve been assigned an IPv6 address in the UniFi internet settings page, although when browsing the web it only shows IPv4 being detected.

[JimM1]

@ThomasBam https://whatismyipaddress.com to see what is assigned both iPv6 and iPv4. IP6 size 56! What Asus is set at to get iPv6 working!

Asus on sky!

[ThomasBam]

Just IPv4 unfortunately.

Strange, as UniFi reports both a WAN IPv4 address and a WAN IPv6 address.

However, that website and others only detect my IPv4 address.

I restarted my AP's and router just in case that ws causing issues too.

[ThomasBam]

I managed to get it working by enabling IPv6 on my default VLAN, selecting 'Prefix Delegation' instead of the 'None' setting, and setting the Zone to Internal.

If I reset my router im sure it would have done this for me but setting it manually worked a treat!