The short answer
You can’t put fibre broadband equipment in the same exchange building as existing ADSL broadband equipment. So if your telephone line goes directly to the exchange there’s nowhere to put the fibre equipment. This means a more complex solution is needed than the main fibre rollout.
Fastershire, which is coordinating the work, has a target for THP or “Total Homes Passed.” They admit that if they have a choice between work which gives an opportunity to bring more THP into the total then they will take it, and if circumstances make it harder to bring some houses in, then they will look to make their target elsewhere.
Click here to find out if you’re affected and what you can do about this, or continue reading for a more technical explanation, and my correspondence with Fastershire.
The longer answer
ADSL broadband is delivered down a pair of copper or aluminium wires which make an electrical connection back to the exchange. The exchange is fitted with equipment called DSLAMs, one per telephone line. Each DSLAM “talks” to the the modem in your house. When you switch your modem on you will see a “DSL” light flashing for a while until it goes solid. That’s the modem establishing the link with the DSLAM.
The further away from the exchange your house, the lower the available connection speed due to losses on the line. If you could shorten the distance over which the internet connection is carried on a pair of wires, then you could increase the speed.
Most people’s telephone lines are routed from the house to a junction box (cabinet) in the street, from where a whole bundle of cables goes back to the exchange. If you could bring a fibre optic connection all the way to the cabinet, and put DSLAMS in there, then you would significantly shorten the distance over which the pair of copper wires is needed, and you could make the copper perform at a much higher speed. This is the technology being installed all over the UK at present, including in Blockley. It is called “Fibre to the Cabinet” or FTTC. It’s efficient since it requires only a connection from cabinet to exchange, and needs no rewiring into individual premises.
However, if you have a line that goes directly to the exchange there is no cabinet where DSLAMs can be installed. So why not put fibre DSLAMs into the exchange itself? Well, you can’t because fibre DSLAMs interfere with equipment in the exchange.
There are a variety of solutions, none of which is as straightforward as building FTTC.
- Building a new cabinet containing fibre DSLAMs remotely from the exchange and rerouting all the existing exchange lines through the cabinet.
- Fibre to the Premises (FTTP). True fibre broadband which needs no conventional wiring. A fibre optic cable is run directly into your house. Very quick indeed and needs individual wiring.
- Fibre to the remote Node (FTTrN). Basically a mini cabinet installed on a telegraph pole or underground. Needs fibre running as far as the telegraph pole or underground.
A little thought will quickly show that none of these is immediately straightforward, although the first option looks like it would deliver the biggest benefit for the smallest disruption.
Here’s my correspondence with Fastershire so far. It does say that “From early planning (which is subject to change) it is suggested that any work to upgrade Exchange Only (EO) lines from your exchange may use FTTP technology. “ but later in the correspondence it says “especially in the case of EO lines, it’s not possible to provide guarantees until a significant amount of work has been carried out. With EO lines we don’t give upfront confirmations because the network rearrangement, whereby individual lines are gathered together into an upgraded cabinet or assigned to an FTTP node, is subject to this sort of on the ground adaptation as progress is made right up until deployment is all but finished.” So they won’t make any decisions about whether Blockley’s EO lines get upgraded until the very end of the project. And if their target for Total Homes Passed can more easily be reached elsewhere, who would blame Fastershire if they ignored the EO lines in Blockley?