Why didn't BT / Openreach keep developing their VDSL2 technology in the UK?

[g67575]

Openreach's 'Superfast' VDSL2 (FTTC) deployments never developed beyond profile 17a, and didn't even max out bandwidth on this profile, since all lines are capped at 80mbps.

The obvious next step could have been deployment of vectoring technology to all cabinets, plus upgrading any cabinets / other equipment that don't support vectoring. This could also be combined with greater backhaul capacity (to allow line speed caps to be removed), as required.

This could have been funded or partly subsidized by the government if necessary, as an intermediate step towards FTTP (which has not been prioritized by the government, with many not due for upgrades until 2026, or not at all).

I know what was hoped for G.Fast, but it never went anywhere, did it?

 

[g67575]

I don't agree, what about the areas with VDSL2/FTTC, with no plans from providers for FTTP network deployments?

Add to this, the very slow deployment of FTTP in rural areas, when vectoring could have helped a great deal to improve speed and reliability of VDSL2 lines.

There was a backlash from many local councillors even with FTTC / Superfast upgrades from ADSL, who in some cases said it was a waste of money / didn't approve of the affect on the local area etc.

EDIT- Vectoring itself even on 17a profiles could allow for at least ~130mbps downstream (max rate), according to this guy, who's area was upgraded back in 2017 (but his line was still capped at 80mbps). Link here:
https://www.increasebroadbandspeed.co.uk/vdsl-vectoring-arrives-on-a-rural-fibre-broadband-cabinet

Vectoring largely solves the issues of crosstalk and signal attenuation over longer lines, on VDSL2. Germany is a good example of where vectoring has been widely deployed, with profile 17a widely available, and higher bandwidth VDSL2 profiles (like 35b) also available to millions of homes.

Ireland's network had vectoring planned from the start for their VDSL2 network, which makes me think the decision not to rollout vectoring was down to penny pinching or poor planning by Openreach.

The reason I think many living in the UK think VDSL2 is crap, is because it never received enough investment here, and simply isn't 'Superfast' for many.

 

[g67575]

Another likely benefit of Vectoring, would be the removal (or toning back) of the DLM system on most/all VDSL2 lines, as it simply wouldn't be needed anymore on all but the longest of lines (or lines with copper cable related problems).

 

[g67575]

I'd rather more places got FTTC, than them upgrading the kit in already enabled places. 80Mbps is plenty.

FTTC coverage is around 95% already. The low hanging fruit has been picked. Might as well upgrade those without FTTC, with a FTTP line now, they will get much better results, and maybe even pay less to use FTTP, with some ISPs.

The VDSL2 technology used is basically the same since 2012 (VDSL2 spectrum increased to ~17mhz), except for the addition of G.INP on Huawei cabinets. So, it's been pretty stagnant since then, in my view.

Openreach has said vectoring is very effective upto 500 meters from a FTTC cabinet (100mbps downstream at this distance, on 17a profile), with significant improvement on lines even beyond that distance.

I'm not suggesting that they will roll out vectoring at this point, merely pointing out that their VDSL2 development and investment in VDSL2 has been very poor, compared to the planned FTTP rollout, which will eventually cover 25 million + homes if all goes well.

 

[g67575]

Get on the 5% then!

Mum's village (population 1800 ish) was stuck on 4Mbps ADSL until a month ago, and that's only because the council paid OpenReach to sort it with grant money. The town about 5 miles away with the exchange, got FTTC'd in most areas 5 years before...

Have you checked this map? It shows you the areas Openreach plans to upgrade to FTTP between now and December, 2026. Link here:
https://api.superfastmaps.co.uk/fibrecities/2.0/

My town is included in the plans, but work might not begin until 2026 (maybe even later?). Although, they haven't committed to specific dates, so I suppose they are trying to keep their options open.

 

[g67575]

There's no point putting effort into copper technologies to permit up-to 130Mbps downstream when the majority of lines will never sync at the maximum rate. Abandoning further FTTC development to shift focus to other technologies was the right call, even if it came with a G.fast misstep in the process.

A lot of lines aren't even seeing half of the 80mbps that many ISP packages offer. If Openreach can't / won't do it, it's a choice governments can make, and one that I think many would support if they had bothered to ask people about improving their existing FTTC connection (even if it's only done with the support of people living in each local area).

Also, more than 60% of FTTC lines are within 500m or less of a cabinet, according to an Ofcom report:

 

[g67575]

I think your position that the government should have funded further VDSL development is based on your own situation rather than a consideration of what makes the most sense at a national level.

I guess we will never find out, cause the government never bothered to ask if this is something people would want, they only became concerned when they started to look bad in international comparisons, and couldn't get through Zoom calls smoothly!

 

[g67575]

There's no shortage of people who will only advocate upgrades for where they live, who insist it just isn't worth doing in other areas.

The reality is, most if not all of us would benefit from internet infrastructure upgrades, and when it's finally done, most can't imagine themselves going back again to an inferior connection.

Do they care if it's FTTP, or highly upgraded FTTC? I doubt it in most cases, particularly in the areas not due for FTTP upgrades.

 

[g67575]

For many years, neither Openreach, nor the government spent money /time on improving VDSL2 or FTTP, it had nothing to do with being committed to FTTP deployments.

Openreach trailed vectoring and G.Fast in a few areas, but that was it.

The government just waited and did nothing, the only thing that happened is that the Superfast coverage gradually crept up. Local councils seemed largely satisfied, as long as this percentage was increasing each year (even as crosstalk was decreasing speeds for many, as more signed up to use FTTC).

Focusing on the technical aspects a bit more, it's clear that the upgrades to a VDSL2 17mhz spectrum were not a particularly efficient or useful for many, but they would have been, if rolled out combined with vectoring. The trouble with the higher frequency signals on this profile, is that they travel poorly over distance, leading to more line errors and only small-moderate improvements in line speed (I've tested this myself, I only get downstream line errors (CRC) when the higher frequencies are enabled on my VDSL2 modem.

So, any further profile upgrades beyond 17a, are contingent on vectoring support for all cabinets, in my view. The higher frequency bands just wouldn't work well over distance, without this technology.

 

[g67575]

I regard April 2012 as the point when the last upgrade to VDSL2 occurred (profile 17a) in the UK, thats what I mean by 'For many years'. From 2012-2013 onwards (Edited) Vectoring (tested by Openreach and confirmed working by this point) and cabinet upgrades (to support vectoring, where required) could have been rolled out.

Link about vectoring tests completed in 2012 on VDSL2 profile 17a, here:
https://www.nokia.com/blog/vdsl2-vectoring-delivers-its-promise/

But the problem from this point, was that the government did nothing / took no interest (sorry to repeat, but it's true).