THE advent of superfast 鈥渁lways on鈥� 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鈥檚 telecoms
regulator. At the same time, Oftel concedes that competition is necessary to
prevent BT gaining a monopoly.
Oftel鈥檚 dilemma centres on Asynchronous Digital Subscriber Line technology,
which promises to deliver broadband Internet and video into Britain鈥檚 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鈥� 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.
鈥淵ou can鈥檛 have a complete free-for-all like they have in the US,鈥� says
Oftel鈥檚 director of technology, Peter Walker. 鈥淭hat鈥檚 why the rest of the world
is watching and waiting to see what happens in the UK.鈥�
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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鈥檚
competitors use their preferred version of ADSL over BT鈥檚 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鈥檚 competitors to
launch in July 2001. BT believes it will take longer, and is getting in early by
spending 拢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, resulting in corrupted data and distorted video.
