Symmetric support on Openreach FTTP?

Is there any reason why Openreach/Wholesale FTTP is Asymmetric (other than protection of a profitable leased line business)?

Because its a contended service which itself asymmetric, 2.5g down and 1.25g up, shared between 16 to 32 users.

That said OR are trialing a symmetric service but it will be a costly install and monthly charge

I was led to believe that Openreach were going to introduce some symmetric FTTP plans this year, but the plan was shelved after COVID-19 hit.

No idea what price they were going to pitch it.

It probably would have been on the 10Gb gpon product = expensive.

In reply to a post by Pheasant:

I was led to believe that Openreach were going to introduce some symmetric FTTP plans this year, but the plan was shelved after COVID-19 hit.

No idea what price they were going to pitch it.

This was rumoured to be a "free upgrade" for people on the 500/165 and 1000/220 products:

https://www.ispreview.co.uk/index.php/2020/02/openre...
https://www.ispreview.co.uk/index.php/2019/06/openre...

If they're doing it with XGS-PON then it will be a better service than the GPON-based service of some of the altnets. Having said that, I suspect there are few households who regularly cane a 1G uplink, except when running speed tests.

In reply to a post by candlerb:

This was rumoured to be a "free upgrade" for people on the 500/165 and 1000/220 products

Interesting. From my own recent experience I can see some downward price pressure on "proper" leased lines, and certainly competitive offers are out there (especially where ECCs are underwritten) as the lines get a bit more blurred between the 'gold standard' that is leased line and high-end FTTP and (soon to be?) symmetric FTTP.

In reply to a post by Taras:

Because its a contended service which itself asymmetric, 2.5g down and 1.25g up, shared between 16 to 32 users.

That said OR are trialing a symmetric service but it will be a costly install and monthly charge

Interesting. So that’s the DP in the pavement chamber / poles.... these are capped by design to handle 2.5g as you said?

I thought there would be a bit more headroom than that.

Edited by oldskool (Sun 19-Jul-20 16:10:16)

It's good to dream. The tech is there, but I just can't see this happening.

Just before the chamber/poles, at the splitter node.
A splitter serves a maximum of 32 homes, usually a few DP's each.

It's those 32 homes that share 2.5Gb down and 1.25Gb up.

That can be upgraded in future to 10Gb down and 10Gb up by upgrading either end of the fibre to XGS-PON.
Just a new ONT for the customer.

The current GPON (2.5Gb/1.25Gb) can run alongside XGS-PON at the same time.

So if someone ordered 1000/1000 then technically OpenReach can upgrade that single line to XGS-PON and leave the other 31 to share the GPON bandwidth.

Some networks split GPON over 128 homes instead of the 32 OpenReach have picked.

A 32 split is unlikely to see much contention. Most homes takes 40/10 or 80/20 services.
Even those on 1000/115 are unlikely to see much contention with just GPON in use.

In reply to a post by oldskool:

Interesting. So that’s the DP in the pavement chamber / poles.... these are capped by design to handle 2.5g as you said?

I thought there would be a bit more headroom than that.

They are all passive so no limiting / capped nothing, the splitter just splits the 1 fibre into 32 fibres, so what goes in comes out all 32 fibres.

Its all down to what is at each end, (i.e. the Exchange and and ONT) so if you change the hardware at the exchange to do 10Gbit the ONT will need to be upgraded to handle that speeds.
However I think the XGS-PON can and does support both 1Gbit / 2.5Gbit and the 10Gbit so the Exchanges could already of been upgraded but just running at the lower speeds.

Well that's my understanding of it.

Paul

Thank you both for the explanation.

In reply to a post by oldskool:

Thank you both for the explanation.

No probs, basically all ONT's connected to those 32 split fibres all receive the same data, but only the ONT that the data is for can decrypt it.

Image of the Passive Optical Network (PON) the bottom section of the image.

Passive is good due to no power required.

Paul

In reply to a post by techguy:

Is there any reason why Openreach/Wholesale FTTP is Asymmetric (other than protection of a profitable leased line business)?

The reason it's as asymmetric as it is is entirely commercial. Upload speeds could be 50% those of downstream.

In reply to a post by Pheasant:

I was led to believe that Openreach were going to introduce some symmetric FTTP plans this year, but the plan was shelved after COVID-19 hit.

No idea what price they were going to pitch it.

Not sure about introducing plans but certainly trialing the technology to support it, which they are.

XGSPON.

Would be at 'business' pricing so within the range of serious enthusiasts / home office users.

In reply to a post by PaulKirby:

Its all down to what is at each end, (i.e. the Exchange and and ONT) so if you change the hardware at the exchange to do 10Gbit the ONT will need to be upgraded to handle that speeds.
However I think the XGS-PON can and does support both 1Gbit / 2.5Gbit and the 10Gbit so the Exchanges could already of been upgraded but just running at the lower speeds.

Just FYI XGSPON is not backwards compatible with GPON. Need to at very least change optical modules in the line cards in the OLT if using Huawei Flex-PON or similar and most likely change the entire board as you can get twice as many GPON ports out of a standard GPON board as XGSPON ports out of an XGSPON board.

I imagine it'll initially be built with both GPON and XGSPON OLTs feeding an area, combined and split at the exchange and traveling down the same fibre from there, with XGSPON introduced as needed.

Could certainly get 1000/500 out of GPON and overlay with XGSPON as capacity relief when needed so really no rush for Openreach to get XGSPON kit into exchanges or cabinets just yet.

In reply to a post by CarlTSpeak:

Not sure about introducing plans but certainly trialing the technology to support it, which they are.

XGSPON.

Would be at 'business' pricing so within the range of serious enthusiasts / home office users.

Pre-COVID lockdown around early March I was looking at FTTP plans to migrate to when my oD contract finished in July. At the time my provider said there were going to be symmetric plans available possibly in the timescale I was looking into. A month or so later, post lockdown etc, I was told those plans were shelved, for this year at least...

As to the cost, anyones guess but I'd imagine sandwiched somewhere between the top of the asymmetric plans and lower end of leased line so probably somewhere around £200 pcm before VAT I would hazard a guess.

In reply to a post by Pheasant:

Pre-COVID lockdown around early March I was looking at FTTP plans to migrate to when my oD contract finished in July. At the time my provider said there were going to be symmetric plans available possibly in the timescale I was looking into. A month or so later, post lockdown etc, I was told those plans were shelved, for this year at least...

As to the cost, anyones guess but I'd imagine sandwiched somewhere between the top of the asymmetric plans and lower end of leased line so probably somewhere around £200 pcm before VAT I would hazard a guess.

Symmetrical by July was always pretty unlikely. The initial XGSPON testing is only relatively recent and of a small scope. Openreach would've published details of XGSPON pilot availability on their various platforms.

FWIW there are companies on symmetrical FTTP via XGSPON on the Openreach network right now. It'll also be used as capacity relief when GPON becomes an 'issue'.

Yes I agree July would have been pushing it, but the impression I had at the time was "this year" perhaps not necessarily July though. Anyhow it's rather academic as all bets are off on that for 2020 at least it would seem.

Perhaps with no more unforeseen interruptions to business and life at large, we will see Openreach offer symmetric plans by this time next year...

From what I understand, GPON and XG-PON use different light wavelengths at 1480-1490nm and 1574-1584nm respectively, so you can use the same fibre, just with different lasers on each end.

Then there's XG-PON1 (asymmetric) or XG-PON2 (symmetric), and then there's NG-PON2 which uses yet more wavelength blocks to aggregate between splits and is effectively 4x XG-PONs all using different wavelengths on the same fibre, but getting 4x the aggregate throughput...

GPON and XG-PON can operate on the same fibre at the same time by using wavelength division multiplexing (WDM) in the exchange and ONT's already contain a wavelength filter.

Thread resurrection. Not much changed it would appear. Any changes rumoured?

Seems like Openreach have firmly shelved any near term plans of an XGS-PON offering.

In reply to a post by Pheasant:

Thread resurrection. Not much changed it would appear. Any changes rumoured?

Seems like Openreach have firmly shelved any near term plans of an XGS-PON offering.

The XGS-PON trial closed for new orders back in January.
It was only available to businesses and only in certain locations I believe.

https://www.openreach.co.uk/cpportal/updates/briefin...

Well that’s the end of that for now I guess. Still tweaking the product at least for business it would appear...

https://www.openreach.co.uk/cpportal/updates/briefin...

https://www.ispreview.co.uk/index.php/2021/03/openre...

In reply to a post by Pheasant:

Well that’s the end of that for now I guess. Still tweaking the product at least for business it would appear...

https://www.openreach.co.uk/cpportal/updates/briefin...

https://www.ispreview.co.uk/index.php/2021/03/openre...

ISPReview have somewhat mixed 2 separate things there.

It looks like it has nothing to do with XGS-PON and is simply a trial allowing a business to be more flexible with ONT location.

They aren't taking orders for XGS-PON at present so a trial allowing an ONT to be installed further away would be useless if it was related to XGS-PON.

Symmetrical and XGS-PON aren't mentioned in the briefing.

Edit: changed the wording of some parts of my reply.

Edited by j0hn83 (Wed 21-Apr-21 17:07:02)

It looks like mention of XGS-PON was made by Mark in passing / as an intro to the potential for “FTTP For Business (aka FTTP Advanced)” as a future service offering. This is a build up / precursor to that but not specially about XGS-PON at all.

The last two paragraphs he sums up as;

“By the sounds of it the Advanced Provision Trial will help Openreach to test some new and more complex installation scenarios on business and public sector sites, which will adopt some of the same things that you might normally expect to see from an Ethernet (EAD) install rather than FTTP.

For example, at present a regular FTTP installation comes with two options – Standard and Premium. One of the differences here is that a Standard install will see Openreach place the Optical Network Terminal (ONT) on your wall, usually within 10 metres from where the fibre enters your building (house etc.). A Premium installation extends this to 30m, but the new Advanced trial can do up to 100m (subject to survey).”

So it’s pretty clear (to me at least) that this trial has nothing to do with symmetric or 10Gb FTTP service but merely to add another dimension of flexibility into the provision of FTTP for business within the premises, much as you can do with more premium EAD type services.

What’s your take on it? Have you got access to the OR portal with the briefing notes? I can’t see it myself as I don’t work for a CP.

In reply to a post by Pheasant:

What’s your take on it?

Pretty much what you just said.

It appears to just be a trial of a new, more advanced/flexible deployment method for businesses, allowing the ONT to be installed much further from the entry point.

The fact this trial has started after the XGS-PON trial has closed for new orders suggests this has nothing to do with XGS-PON/symmetrical services (for now at least).

Of course there's no reason this advanced provisioning/deployment method can't be used with any future XGS-PON trial / fully launched product, but it doesn't appear to be directly related to it.

Have you got access to the OR portal with the briefing notes?

Not personally, but I know a couple people that do.
Neither are willing to paste me the briefing notes in full, but both are usually happy to answer any queries I have about them.

I'm informed there's no mention of XGS-PON or symmetrical services in this particular briefing, which makes sense with that particular trial being closed to new orders.

There is of course no reason why Openreach couldn't do symmetrical now, which I think is people really asking for higher upload speeds. On GPON upload is at half the speed of total download speed (2:1), so if a 1:1 symmetrical service is offered it means upload is twice as contented locally, but no reason why 1000/500 couldn't be a product, as that sees the same theoretical contention on both up and down.

At the moment the issue is really that Openreach are protecting sales of their leased line solutions. For example, Openreach price the FTTP1000/115 product at £378.00. They also do a FTTP product with double the upload speed (1000/220), and in order to get another 100Mbits/s on the upload, you have to pay over double the price at £969.00.

It is less about the technology and contention ratios, more about money I think.

In reply to a post by E300:

At the moment the issue is really that Openreach are protecting sales of their leased line solutions. For example, Openreach price the FTTP1000/115 product at £378.00. They also do a FTTP product with double the upload speed (1000/220), and in order to get another 100Mbits/s on the upload, you have to pay over double the price at £969.00.

Plus a £500 connection fee.