Skip Navigation

How fast will FTTC run at?
Tuesday 10 April 2012 10:50:10 by Andrew Ferguson

With 12 years experience of how ADSL performs in the UK there is a wealth of guides to help people estimate what speed they will receive. The arrival of ADSL2+ changed the estimates, and it favoured those who lived within 3.5km of the exchange. Many claimed that Fibre to the Cabinet would not offer good speeds to many people, but the data available suggests that just under 90% of telephone lines that are connected to a street cabinet will receive 24 Mbps or faster. Compared to the current UK average this is a boost of around three times.

We have created the table below to try and help people understand what speed they may receive from fibre to the cabinet, compared to the real world figures that we published on Saturday the figures look low, that is because the source data was taking into account crosstalk which could potentially arise once FTTC services are very popular. This crosstalk is what vectoring should mitigate, but deployment of this is still a couple of years away.

For those in areas where FTTC is available, the telephone number look ups can give an estimate, but the table below allows people to assess how reasonable that estimate is, assuming you know where your street cabinet is located (out of the 85,000 or so Openreach has).

Distance to cabinet (metres) Estimated connection speed Cumulative%'age premises at this distance
100m 100 Mbps 5%
200m 65 Mbps 20%
300m 45 Mbps 30%
400m 42 Mbps 45%
500m 38 Mbps 60%
600m 35 Mbps 70%
700m 32 Mbps 75%
800m 28 Mbps 80%
900m 25 Mbps 85%
1000m 24 Mbps 90%
1250m 17 Mbps 95%
1500m 15 Mbps 98%
VDSL2 Profile 17a, cabinet to premises speed estimate

Not all telephone lines in the UK are connected to a cabinet, the vast majority are. In terms of superfast broadband solutions for those areas, we are still waiting on Openreach and the BDUK/local authority projects to announce their preferred solution. These exchange only lines are often the properties closest to the exchange, or new estates of 100 or properties squeezed onto an exchange years after all the original infrastructure was in place.


Posted by herdwick over 5 years ago
Presumably an estate of 100+ properties could be addressed by putting a hypothetical axe through the cable, wiring in a PCP cabinet and hooking up an FTTC cabinet to go with it ?
Posted by andrew (Favicon staff member) over 5 years ago
Potentially, even if cabinet was just outside exchange building, or FTTP deployed.

Oddly left out of both of these.
Posted by New_Londoner over 5 years ago
Impressive to see that FTTC could deliver > 40Mbps to around half of us, and > 24Mbps to 90% of us (ignoring exchange only lines).

So much for comments from others about it not be a worthwhile solution, especially when you coudl see further speed improvements from Profile 30a, vectoring etc.
Posted by andrew (Favicon staff member) over 5 years ago
Added a similar table for ADSL/ADSL2+ into our FAQ section
Posted by andygegg over 5 years ago
Well, I'm about 4km from the cabinet...
Posted by andrew (Favicon staff member) over 5 years ago
In which case base speeds on the ADSL2+ tables. The improvement will depend really on how much cable there was between the exchange and cabinet initially.
Posted by qasdfdsaq over 5 years ago
Curious estimates, highly conservative yet not conservative enough. I'm 85m from cab (straight line) and 110m line length, with a max speed of 85mbps sync. I'm on a small cab, so you'd expect less crosstalk.

Phone line checker gives me an estimate of 55mbps though.
Posted by chrysalis over 5 years ago
whilst FTTC is a huge improvment over adsl thats welcomed, the sad thing is its not far off been obselete in itself (within 3-6 years) and BT really should have gone the FTTP path.
Posted by themanstan over 5 years ago
The problem there being that people would not be prepared to wait to get that kind of service. People complain about how slow it's been to get FTTC, imagine the howls of inequity if FTTP had been rolled out nationwide to 66%, we'd be still waiting for works to end in 2020...
Posted by themanstan over 5 years ago
I'm wondering whether the wholesale checker estimate allows for a certain level of crosstalk, hence the underestimated speeds that it gives.
Posted by themanstan over 5 years ago
BT Wholesale checker is reporting the 80/20 speeds again.
Posted by cyberdoyle over 5 years ago
Does anyone have any figures for the exchange only lines in rural areas where there are no cabinets? ie how many there are? How can we ignore them?
Also does anyone know how many cabinets won't be enabled for fttc even when bt get all the funding?
Until we have those figures we can't really say that 75% of us will get superfast can we?
Winston Churchill loved stats. he could make them say anything he liked.
Posted by themanstan over 5 years ago
This is something UKgov has been ignoring or unwilling to open the cheque book for.

EO long rural line are in the same boat as off gas grid residences. An alternative to the norm is only available, they are often not cheap nor as good as regular services.

At the same time, who should cough the cost of connecting these people? Should it be like USO where the utility pays the first £35.k then the customer pays the rest?
Posted by themanstan over 5 years ago
£3.5k typo
Posted by cyberdoyle over 5 years ago
All the water falls on these rural areas, and is piped to the urban ones. you don't pay any more for your water do you? A utility company is just that, it takes the rough with the smooth and provides a fit for purpose service. The government made funding available for the hard to reach areas, but it looks very much like it isn't going to reach them...
Posted by andrew (Favicon staff member) over 5 years ago
@cyberdoyle and conversely one cannot complain that people won't get it until the projects are complete can we
Posted by themanstan over 5 years ago
CD water falls everywhere (and is almost 100% provided for), gas and elec don't. And I rate gas, electric and water as necessities, yet it's still the case that 4m homes don't have access to gas. Broadband, very much as it is useful is not a necessity. And water is not delivered by rural communities, if it was your argument would hold "water".

The majority of people i know who live in rural areas, do so because of the quality of life that this "isolation" gives, hand in hand with that isolation is the difficulty of obtaining services that are readily available to urban areas.
Posted by jamesking over 5 years ago
How does this stack up to the figures provided by Digital Region in the previous news article?

These seem considerably slower, but I can't work out why the difference.
Posted by themanstan over 5 years ago

These figures allow for a considerable amount of crosstalk. As the cabinet populates the signal from other users is picked up and contaminates your signal as noise. This results in an effective drop in speed as the amount of signal power used increased to overcome the noise. That make sense to you?
Posted by LeJimster over 5 years ago
These figures look ultra conservative to me. I guess there is no harm in dampening expectation. but with good line quality and and vectoring the majority of FTTC customers can achieve over 50Mb.
Posted by LeJimster over 5 years ago
BTW, I thought BT was introducing line vectoring later this year. I'm sure the plan was to bring the 80/20 product to market in Spring and then in Autumn introduce vectoring.
Posted by jamesking over 5 years ago
Thanks themanstan!

LeJimster - what's vectoring? Making it even faster somehow?
Posted by andrew (Favicon staff member) over 5 years ago
Conservative - because take-up and crosstalk was accounted for.

Also I have NOT included vectoring, because no launch date yet. Obviously will update once that is known.

Vectoring helps to mitigate the effects of cross-talk. VDSL2 is more affected by cross-talk than ADSL2+, at least that is the theory and results from testing.
Posted by themanstan over 5 years ago
Vectoring analyses the noise (positive) coming your line is taking up. The hardware part then mimics the noise using reverse signal (negative).
As vectoring can't mirror your noise perfectly it blankets (positive and negative signal cancelling each other out) a large portion of it. This returns your speed to near the theoretical maximum for the line length you have.
Posted by jamesking over 5 years ago
Guys, again, thanks for the education. So it's like noise cancelling headphones for VDSL copper lines :)
Posted by themanstan over 5 years ago
Spot on same technology, just working at a different part of the electromagentic spectrum.
Posted by rjohnloader over 5 years ago
And our village of 160 houses is 4000 metres from the cabinet with a chunk of rotten aluminum in the way. Who knows we may get 2-3 mb/s. Thanks for very little, BT
Posted by Petworthman over 5 years ago
In our village of 80 houses there is a fibre connection to the school, but BT (and the County Council) deny that the local exchange (3.55km away) is fibre enabled. So we suffer from very slow overhead copper that disconnects every time a large lorry passes.
You must be logged in to post comments. Click here to login.