SOTAP and SOADSL

I'm confused.

Mark J (a usually reliable source) here seems to imply that SOADSL is ADSL2+ broadband without the voice, and that SOTAP is/will be a transitional voice-only product for areas with neither FTTC nor FTTP. But this page is 4 years old, so maybe things have changed since. This more recent page describes SOTAP as SOGEA for ADSL, ie a data-only product.

SOTAP is unambiguously an OR product. It's described as broadband and voice over IP, so not voice-only. I can't find any mentions of SOADSL on OR webpages (but I might have missed some, of course). OTOH, BTW pages (eg the broadband checker) refer to SOADSL but not SOTAP. So is SOADSL just the BTW name for OR's SOTAP?

One commentator here seems to say that SOTAP is an umbrella term for SOADSL and SOGFAST (and possibly SOGEA too, it isn't clear (well, not to me)). Several others (example) say that SOTAP and SOADSL are the same thing.

And to muddy the water even more, last November something called 'SOTAP for analogue' appeared. This seems to be an emulation of the PSTN on the customer side, delivered to customer prem over copper, powered from the exchange, and carried over some network somehow. In this context, SOTAP seems to imply voice.

Please can anyone shed any light on all this, preferably with a few links/references to reliable sources?

Edited by Thaumaturge (Tue 27-Feb-24 12:20:50)

SOTAP is ADSL without WLR/PSTN. It is to ADSL what SOGEA is to FTTC.
It's a broadband only product but providers can add VOIP if they wish.
It is only available where ADSL is the only option.

SOTAP for analogue is a new product. It's a voice only product that doesn't need broadband to run over.
It is available nationwide but it is only available to existing users of landline only connections.
It saves them having to switch to a digital voice/VOIP product which in the case of FTTP would require 2 powered devices (ONT and Hub with phone port) and it will continue to work with care alarms/security alarms without them needing upgrading to work with VOIP.
Like SOTAP it is a temporary, transitional product.

I only found out about SOTAP for analogue this morning so excuse any inaccuracies in my post.

In reply to a post by j0hn83:

SOTAP for analogue is a new product. It's a voice only product that doesn't need broadband to run over.
It is available nationwide but it is only available to existing users of landline only connections.

Presumably that would require intact E-Side pairs and an exchange with functioning PSTN/WLR capability? If an exchange were to close due to the PSTN switch off then I guess the line would have to connect to another exchange?

Edit, just read this: Openreach states...that this solution “provides point to point copper access between an end customer premises and the CP equipment using pre-existing LLU [Local Loop Unbundling] ties within the exchange. It is required to allow end customers who have a WLR3 only line today, to maintain a working voice only service.” https://www.ispreview.co.uk/index.php/2023/11/openre...

Edited by 4M2 (Tue 27-Feb-24 16:37:47)

In reply to a post by 4M2:

In reply to a post by j0hn83:

SOTAP for analogue is a new product. It's a voice only product that doesn't need broadband to run over.
It is available nationwide but it is only available to existing users of landline only connections.

Presumably that would require intact E-Side pairs and an exchange with functioning PSTN/WLR capability? If an exchange were to close due to the PSTN switch off then I guess the line would have to connect to another exchange?

It will need an exchange with E-Side yes.
I think there's only 5 exchanges planned to close with PSTN. There's a total of only 100 due to close by 2030 which is when this product is intended to last until.

It should only require a PSTN card in the ADSL MSAN, which is already how Talktalk do their landlines.
It won't use any of the PSTN kit, that is still being retired.

https://www.ispreview.co.uk/index.php/2023/11/openre...

Seems like we both found that ispreview article today

It great news that analogue voice lines can be retained - the idea of VOIP as a possible total placement for PSTN after 2025 did seem somewhat unreasonable.

Thanks folks, but what then is SOADSL, and how does that fit into the picture?
That was really the point of my OP.

In reply to a post by Thaumaturge:

Thanks folks, but what then is SOADSL, and how does that fit into the picture?
That was really the point of my OP.

Exact same thing.

Openreach have a product called SOTAP.
BT Wholesale buy SOTAP and sell it as SOADSL.
Different terminology for the same thing.

That's what I guessed in my OP, but I couldn't find confirmation anywhere. Thanks for clarifying.