SDSL: Step forward or back for broadband?

While not every SME will find that they need to switch immediately, SDSL is seen as particularly suitable for those organisations that need to move large files or videos around quickly, such as those in the media, design, print, legal or pharmaceutical industries, according to Clive Longbottom, service director at analyst firm Quocirca.

Despite the expense involved in paying to use a phone line, many organisations continue to use ISDN because of its fast upload speeds.

The technology is also appealing to firms undertaking a lot of videoconferencing because it prevents choppy images at the other end and it could become popular among organisations that need to link disparate sites, stores or warehouses. Running a virtual private network over an SDSL line is anticipated to be almost as secure as, but much cheaper than, its leased line equivalent.

Another expected application, no matter what the size of company, is backing up files remotely rather than having to manually take tapes and other media offsite to store them.

But despite the fact that SDSL technology has been around for several years, it is precisely this appeal to large corporates in terms of potential cost savings that has led to the incumbent telecoms players dragging their feet in introducing it.

Big telcos dragging their feet
"SDSL is seen as a technology that will cannibalise leased-line revenues in certain areas. Leased lines are very lucrative for the incumbents and SDSL is a lot cheaper, so they've held back a bit," says Caroline Bryan, managing analyst at Datamonitor.

There are undoubted downsides to SDSL for the average SME too, the main one being price. While installing an ADSL connection will set customers back anything from £50 to £250, depending on whether they do it themselves or bring in an engineer, introducing an SDSL line could cost around £950. And despite the fact that SDSL is being positioned as an upgrade, it requires new equipment that can only be installed by an engineer. At the moment, moving from ADSL to SDSL means ripping out the old line completely and replacing it with the new technology.

Moreover, while BT charges £130 per month for a 2Mb ADSL line rental, the equivalent for SDSL is a huge £345, although two other speeds are also available -- a 512Kbps connection costs £170 per month, while a 1Mbps line is £230.