High-speed clash

 作者:冯氘锐     |      日期:2019-03-08 05:05:00
By Barry Fox THE advent of superfast “always on” Internet connections through an ordinary phone line will be endangered by crippling electromagnetic interference if there is a free-for-all between competing companies, says Britain’s telecoms regulator. At the same time, Oftel concedes that competition is necessary to prevent BT gaining a monopoly. Oftel’s dilemma centres on Asynchronous Digital Subscriber Line technology, which promises to deliver broadband Internet and video into Britain’s homes. BT has been running consumer trials of ADSL in Suffolk and north London, and wants to capitalise on this lead. But Oftel fears there will be serious interference between rivals’ lines if BT is allowed to go ahead, and competing companies then come onto the scene using overlapping frequencies. BT, however, wants to set the standards for the phone lines that it owns. Whoever wins, the issue is sounding warning bells for the fledgling ADSL industry in the US, where the interference issue has not yet been considered. “You can’t have a complete free-for-all like they have in the US,” says Oftel’s director of technology, Peter Walker. “That’s why the rest of the world is watching and waiting to see what happens in the UK.” Conventional copper telephone wires are designed to carry analogue speech frequencies up to 4 kilohertz. ADSL uses a special modem in the home and another at the telephone exchange to extend this to 10 megahertz. Future systems, such as High and Very High data rate DSL (HDSL and VDSL), will offer up to 50 megabits per second. International standards for ADSL leave providers free to juggle frequencies and data capacities to suit local conditions. Oftel wants to let BT’s competitors use their preferred version of ADSL over BT’s lines. It accepts that this risks interference between mismatched services as they run close together in underground ducts, but hopes to work with the Radiocommunications Agency to iron out clashes. BT would rather control the technology by itself. Oftel thinks the problems can be sorted out in time for BT’s competitors to launch in July 2001. BT believes it will take longer, and is getting in early by spending £5 billion on upgrading its network. Last week, BT contracted Fujitsu and Alcatel to fit ADSL equipment in 400 exchanges, serving 6 million homes, by spring next year. Walker believes the US was wrong to allow free competition without anyone managing the ADSL spectrum. He says that as unregulated services proliferate, they will start interfering,