Expecting new FTTP, how much CBT capacity is deployed?

Hi all, new to this forum and have found much useful information, hoping you can all help me with a query.

I currently have a good FTTC service with BT - I'm only about 100m from the cabinet, and speedtests generally show around 70/18 Mbps. But, I'd always like better, and it looks as though FTTP might be coming our way soon.

I met some Openreach employees in the lane to the rear of our flats a few weeks back who told me they were looking for the best place to install new telegraph poles, which they thought would be for fibre distribution. I now see that OR has roadworks planned in the lane for the end of October for "2X POLE PROVIDES on C/way" (from Roadworks Scotland website).

My question is regarding how much fibre capacity they are likely to install. My understanding from reading the various guides and posts on this forum is that they will put a CBT at the top of each pole, and this typically has 12 connectors, each supporting a single end-user. However, these poles will be servicing just over 100 flats, so that would lead to capacity constraints pretty much instantly.

Is it possible that they will put multiple CBTs on each pole? Or can the fibre from the pole CBT be split again at a distribution point closer to the individual flats?

For background, I live in a tenement flat in Glasgow. The block I am in is 4 storeys, and split into about 7 "closes" (as we call them around here) - each close is a door to a shared stairwell that has 2 flats on each floor. So, 7 closes each with 8 flats, for 56 flats per block - and the lane where the poles are being placed runs between two such blocks, so ~112 flats in total.

The existing copper connection runs from a duct at one end of the lane and then snakes along the back of the block connecting to multiple 'black boxes' (which I presume are some sort of copper distribution points), roughly one per close, from which telephone cables then run to individual flats. I am wondering if there may be additional similar fibre distribution points on the back of the block splitting the fibre again for each close?

If there isn't some way of getting many more fibres from these two poles then I'll need to make sure I get my FTTP order in super quickly once it goes live!

Thanks in advance for any insights.

Openreach will plan capacity for one CBT port per customer premise (UPRN). In the case of large blocks of flats this could mean one or more CBTs per block, which could be mounted on the outside of the block or inside, depending on what's negotiated with the owner. This is all decided by the network planners.

OR's strategy is eventually to retire the whole copper network, so they *have* to install sufficient capacity to cover all existing copper services being migrated to fibre. So don't worry about having to be the first to order.

At the other end of the spectrum of possibilities: if the landlord refuses permission or doesn't answer requests, you may get missed out of the current FTTP rollout completely. You'll just have to wait and see!

potterer

Some blocks of flats are being served by Poles to run the fibre to a CBT on the block. then into the flats. This would then indicate 1 8 port CBT per 'close'

If this doesn't occur with your site you are correct there will be a problem. A single pole will be unable to cope with 56 Fibre drops even if they are spread over both blocks to even out the strain in one direction. It is possible to provide 5 12 port CBTs on a pole and this is likely to be done 1 at a time to fulfill demand but the strain from the drops is very likely to cause a problem if fully used.

It looks like a planning issue in that a planner has thought of the first stage of rollout but not ensured that the design can cope with a full rollout!

Witchunt may like to comment if he sees this thread.

Have Openreach started rolling out their new CommScope made Novux HST range of CBTs? these new CBTs are not limited to a single fibre per port as the Corning ones are.

In reply to a post by candlerb:

At the other end of the spectrum of possibilities: if the landlord refuses permission or doesn't answer requests, you may get missed out of the current FTTP rollout completely. You'll just have to wait and see!

It's a Scottish tenement so there's no landlord. Flats aren't on a leasehold as in England. Each flat owner owns the building along with the other owners. If the OP isn't an owner but is renting and even if the actual owner doesn't respond there will be enough other owners voting to see FTTP installed. Its all in the missives!

Thanks for all the replies. It sounds like the two poles will be a limitation unless there's scope for further fibre splitting, possibly mounted on the building's external wall?

I've also just found out that Cityfibre are building out in our area in the same time frame - there are some paint marks at all the front doors in the street, and they have roadworks scheduled from October through January.

Seems like FTTP is like buses - you wait years and then two come along at once. Looks like we could soon have Cityfibre in the front and Openreach in the rear, as it were.

And @Woolwich has it right - no leaseholders here, it would just need a majority in each close to get permission for any works on the building fabric.

Thanks again, and I will update when works start.

A 3 way bracket mounted to the pole can take 3 x 12 port CBTs. But wall mounted CBTs would possibly be a more suitable solution and save a lot of time later on.

Edited by witchunt (Thu 29-Sep-22 21:06:03)

In reply to a post by witchunt:

A 3 way bracket mounted to the pole can take 3 x 12 port CBTs. But wall mounted CBTs would possibly be a more suitable solution and save a lot of time later on.

But 36 separate cables, if they all pull in roughly the same direction, would be a high pole load. Hence my suspicion that the CBTs will go elsewhere.

They may be using the pole just to bring a fibre uplink. They could even give each block its own splitter node, in which case one 4-strand fibre cable could serve 128 properties.

I guess you'll just have to wait and see what the planners have designed.

If you see some of the fibre builds, with multiple PIA networks all mounting their own equipment on the same poles you can see pole loading is going to be an issue. In this case external mounted CBTs maybe better option as it removes the whole issue of loading and pole top capacity.

Edited by witchunt (Fri 30-Sep-22 18:18:16)

Sounds like the best solution would be one 8-way CBT per close, mounted on the rear wall. That would need ~7 fibre runs from each pole.

Is there any info on how many fibres run to each pole, and what the "fan-out" can be?