BT fixing fibre-optic broadband problem

Tens of thousands of homes can't get ADSL because their connection to the local exchange is partially fibre-optic, but help is at hand

BT is close to fixing a long-running network problem that means almost 30,000 homes currently cannot get ADSL because they are connected to the local exchange by optical fibre.

Back in the 1980s, BT used fibre-optic cable to connect some of its street cabinets to local exchanges, typically when new housing developments were being wired up. Unlike the traditional copper lines -- which were usually still used to connect individual houses to the street cabinet -- fibre-optic doesn't support ADSL.

BT first announced late in March that it was actively working on a solution for this problem, and on Thursday a company spokesman confirmed that BT hoped to have implemented a fix within a few months.

"Some 28,000 homes are currently affected. Although it's a small proportion of our total customer base it is another section of people who currently can't get broadband, and we're trying to solve the problem," a BT spokesman told ZDNet UK.

BT's solution is to add a copper connection between the street cabinet and the local exchange. In some cases, there is already a copper link as well as the fibre-optic, so the telco will use this existing copper and add more when necessary so that ADSL will work from the home to the local exchange, via the street cabinet.

More details about this plan are expected to be announced later this month.

Ironically, faster broadband services such as VDSL rely on a fibre-optic connection from a BT local exchange to a streetside cabinet, but this kind of technology isn't yet being commercially deployed.

There is the standard ADSL caveat, though, that a customer's phone line will only support broadband if it is less than 5.5km (soon to rise to 6km) long. At the moment, this restriction means that around 6 percent of homes can't get broadband even though their exchange is enabled.

For the houses currently affected by the fibre-optic problem, the percentage could be higher.

"In some cases, the reason that fibre-optic cable was used was because of a problem of line loss caused by the distance from the street cabinet to the exchange," said the BT spokesman.

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