Different voice phone and broadband providers with FTTP?

I've recently moved into a new-build house and it just has a fibre-to-the-premises line installed. OpenReach have come round and installed their ONT (optical network termination) box.

The ONT box has one socket with an ethernet cable coming out of it, and one socket with a phone cable coming out of it. Now, as I understand it, it's possible (even with FTTP) to use one provider for the phone, and another for the broadband.

However, this seems to be much more of a headache with FTTP than it was with FTTC. With FTTC I just told BT I wanted phone service with them, and Zen I wanted broadband-only with them, and I got deal from both that didn't break the bank. With FTTP, however, BT are telling me that to get phone-only service from them, I have to pay £20/month (!!!!!) and then in addition I'd have to pay £35/month to Zen.

In an ideal world, I'd just go with Zen for both, but Zen don't yet offer a phone line package, annoyingly.

So I was hoping some people here had some knowledge about what my options are. Let's say I want to use Zen for my FTTP broadband at £35/mo. How can I get a phone line service from another provider? Which providers will do it, and will any of them do it for less than £20/month?

You should consider VOIP for your phone service - sipgate provide a basic service with a free number, no monthly line rental and low calling costs from 1p per minute - unlimited call plans are also available. You can connect existing DECT phones using an ATA adapter or buy a new wireless VOIP phone.

In reply to a post by jez9999:

The ONT box has one socket with an ethernet cable coming out of it, and one socket with a phone cable coming out of it.

I thought I read somewhere that BT were withdrawing use of the telephone port on the ONT for new customers which isn't the end of the world as you can still use VOIP via an analogue terminal adapter (ATA) or a compatible DECT phone if you don't want your telephone line coming over a copper cable.

I'm just interested in the technical difference between using the phone socket on the ONT box and plugging a VoIP box into the internet router. What's happening differently behind the scenes?

Isn't that answered in your other identical thread?

The other thread has a reply saying that you plug the phone into the Openreach box rather than the router. It doesn't say why that is done, and what's different technically about how the VoIP is implemented that means you plug it in to a different box.

If you have a BBU ( Battery Backup Unit) the phone will continue to work if the local power is down. If the FTTP service fails completely both will stop working.

The FTTP is powered from the distant exchange and Your equipment is powered at your end. The exchange has backup batteries ( and generators) the BBU supports your Voice port and VLAN over the FTTP NOT the BB part. You would need a phone that does not require mains power to use the port in these circumstances ( Not a DECT phone unless you have your own UPS for it)

A VOIP service will stop if you lose local power as it is over the BB part of the FTTP.

VOIP goes over the BB part of the FTTP via your BB provider and the internet to your VOIP provider who will then route your call to a normal PSTN service. If VOIP end to end it will be connected via the Internet to the distant customer.

The BT service uses a separate VLAN ( path) over the FTTP ( 128Kbit) that is routed via the FTTP, then BTs core network using a call control to route it into BT's voice network or to another VOIP customer. Only Major difference is the power backup and the separate VLAN.

In reply to a post by jez9999:

I'm just interested in the technical difference between using the phone socket on the ONT box and plugging a VoIP box into the internet router. What's happening differently behind the scenes?

I thought (my usual caveat of I may be talking garbage applies) that the main difference was that the FVA service via the phone socket on the ONT was a dedicated 128k channel separate from the main data channel.

Edit: Just seen the reply from kitcat it explains the difference so much better

Edited by deleted (Thu 24-Oct-19 22:27:46)

Are you saying the power for the phone socket comes from the exchange? Does that mean that the "fibre" line coming into the house also has a copper line? Fibre can't carry power.

In reply to a post by jez9999:

Are you saying the power for the phone socket comes from the exchange? Does that mean that the "fibre" line coming into the house also has a copper line? Fibre can't carry power.

No that's not what being said, the ONT effectively has an analogue terminal adapter built in so its power is via the ONT mains power source in your property. Some people who don't use the ONT phone socket choose to retain their copper telephone line (if the property has a copper feed) or use a separate analogue terminal adapter with a separate VOIP supplier.

Edit: Some ONT's have a separate battery backup unit (BBU) fitted next to them (or in the combined enclosure) but in recent weeks/months Openreach have stopped supplying these so you may not have one that just means unless you have some form of local power generator the telephone socket on the ONT (as well as the broadband which was never protected by the BBU) will stop working if your property loses power.

Edited by deleted (Fri 25-Oct-19 10:36:07)