Full Fibre To The Property with Digital Voice and Third Party Router

[DarkFibre]

Thanks imjolly. Do you know how I would access the SH2 via the router, in order to stand down its Wi-Fi output? Would I need to find it within the network via its IP address or something?

[imjolly]

the Hub has to be connected to ONT to get DV to work.  you can then connect your router to hub lan to lan then turn of wireless in hub using hub manager/wireless and also turn of DHCP so you router allocates the IP address to devices.  this is covered in more detail in numerous posts on the forum found using search

[DarkFibre]

OK thanks imjolly. Sounds complicated but I would give it a go before switching to VoIP if I have to

[KennethS]

@DarkFibre Definitely no harm in trying if you have time.  Having done a bit of reading while waiting for our FTTP installation (which triggered the switch by BT from analog phone to Digital Voice) I was unconvinced it would work (or work without potential issues).  Without wanting to get too technical, which I am not, having two functioning routers in a system can cause a double-NAT situation.  I think for the Digital Voice to work, the SH2 will need to be the first router in the connection to the ONT (the terminal that you attach a router to for internet).  Since I could not find any way of disabling the SH2's DHCP server function (to disable its routing functions so to speak), from what I could glean putting my router downstream from the SH2 results in the double-NAT issue.  It may not cause problems, but we have a very significant number of wired and wireless devices in the home and I was pretty certain I would face issues.  I think turning WiFi off in the SH2 would likely not be overly difficult but that would not have overcome the two routers in sequence problem I wanted to avoid.

[KennethS]

@imjolly -- that is interesting. When I was searching the forums I could not find any instructions on how to disable the DHCP server in the SH2.  A call to BT technical support was unhelpful as they said it was not possible. I will do another search now, mostly as a learning experience since I am quite happy with our home setup and have already moved to a different VOIP service for "landline" home phones.

[sammy4703]

To disable DHCP:-

[licquorice]

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@KennethS wrote:

@imjolly -- that is interesting. When I was searching the forums I could not find any instructions on how to disable the DHCP server in the SH2.  A call to BT technical support was unhelpful as they said it was not possible. I will do another search now, mostly as a learning experience since I am quite happy with our home setup and have already moved to a different VOIP service for "landline" home phones.

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Disabling the DHCP server does not prevent double NAT, nor does it stop the hub routing. It just stops the hub issuing IP addresses to clients.

[Johnbrid]

I am not sure you need to worry about double NAT issue. I have two properties both with two routers. Both the second routers are asus and were configured with their automaic software. In one case the primary router is the bthub as it is an FTTP line. In that case the BT hubs wifi is switched off. The BT hubs wifi is nothing like as good as the asus wifi in speed or reach.

I had heard about the double NAT issue but have never experienced any issues at all. I suspect that is due to the way the asus routers are configured automatically but I am not an expert. It just works. One of the second routers services three holiday cottages so has all sorts connected to it and lots of them. it has operated for over two years without any problems.

[KennethS]

Thanks all, this is useful and helpful information. It was a couple of years ago that FTTP was installed.  At that time it didn't seem there were easy & secure ways of using both the BT-supplied HomeHub and my existing Synology mesh system.  I opted for SipGate to replicate our landline phone line and have never opened the boxes for the BT-supplied equipment.  Too much of a faff now for me to try a reconfiguration when all is working well and stabile.  

This is all good information however in the unlikely event that I decide to change my router setup.

[licquorice]

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@Johnbrid wrote:

I am not sure you need to worry about double NAT issue. I have two properties both with two routers. Both the second routers are asus and were configured with their automaic software. In one case the primary router is the bthub as it is an FTTP line. In that case the BT hubs wifi is switched off. The BT hubs wifi is nothing like as good as the asus wifi in speed or reach.

I had heard about the double NAT issue but have never experienced any issues at all. I suspect that is due to the way the asus routers are configured automatically but I am not an expert. It just works. One of the second routers services three holiday cottages so has all sorts connected to it and lots of them. it has operated for over two years without any problems.

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Double NAT is only really a problem for gamers and people port forwarding to cameras etc,  for normal use it is totally transparent.