BT has announced the next 500 exchanges that it plans to upgrade to business-grade, symmetric broadband - SDSL - as part of the 12-month SDSL expansion programme that it revealed at the end of last year.

BT reckons that the next 500 exchanges have been selected according to the level of demand for SDSL, and where there is a high density of small and medium sized businesses (SMEs) within coverage of the exchange. The demand levels have been assessed by wholesale service providers, and reported back to BT.

Remoter areas of the mainland gain most, as counties such as Cornwall and Cumbria get SDSL for the first time, the former gaining four SDSL-enabled exchanges, the latter five. Northern Ireland gains most: it currently has no SDSL-enabled exchanges but will have 24 by the end of the phase-in. Back on the mainland, Dorset is the biggest winner, going from zero to 12, while Lincolnshire moves from zero to seven. Somerset will gain four SDSL exchanges where none existed before.

Other big winners are Derbyshire (one to eight), Devon (three to 14), and Nottinghamshire (one to 14). Scotland does well too, moving from 21 exchanges to 40. London more than doubles its share from 97 to 170.

The first 500 exchanges will be upgraded over a six month period starting from April 2005, said BT. The next phase of the roll-out programme starts in August 2005, when BT will identify a further 500 exchanges for SDSL enablement. BT said that service providers can nominate exchanges for this second phase of its roll-out programme up until the end of June 2005 so, if your exchange doesn't appear on the list, hassle the SP.

The full list of exchanges is available from BT's Web site.

On completion of the roll-out programme, which will be carried out in two phases, a total of 1,300 exchanges will be enabled for SDSL services. This will bring high speed symmetrical broadband services to over two-thirds of UK businesses.

Bruce Stanford, products director for BT Wholesale, said: “This represents a huge commitment on the part of BT to further enhance our wholesale broadband offering by accelerating the roll-out of SDSL. The wider geographic availability of our wholesale SDSL products will allow more service providers to meet the needs of the growing proportion of smaller businesses, remote office and teleworkers that require business-class broadband services, as well as generating new revenue streams from the introduction of value-added services.

“Before the end of this financial year, 300 exchanges will have been switched over to SDSL. In a little over 12 months time, that number will have quadrupled, bringing symmetrical data services within reach of the majority of UK businesses.”

BT Wholesale’s SDSL products include BT IPstream Symmetric and BT Datastream Symmetric. These products are sold on a wholesale basis to service providers who then retail SDSL services to end users.

SDSL is suited to business use because it offers equivalent upstream and downstream data rates. This makes it appropriate for applications such as Web hosting, branch or remote office connectivity, and VPNs.