The next generation of DSL is going to be even faster and could be the answer to the knotty problem of how to get broadband services to rural areas.
VDSL (Very High Speed Digital Subscriber Line) is currently being tested by BT in cooperation with 12 other European operators. It promises download speeds of up to 14Mbit/s and upload speeds of 3Mbit/s. It will be particularly useful in homes with multiple PCs and televisions -- BT hopes to deploy it by the end of 2002.
VDSL is, like ADSL, limited by distance, and performance worsens as the distance from the telco's equipment increases. But unlike ADSL, where the equipment is being deployed in telephone exchanges only, VDSL can be put in streetside cabinets to act as a midway point between those exchanges and people's homes.
The fact that VDSL can be installed closer to homes makes it an ideal solution for getting broadband to remote areas. The government is keen to find as many platforms for broadband as possible in an attempt to prevent a rural/urban broadband divide, but there are still obstacles to overcome.
One such stumbling block stopping VDSL from fulfilling its perceived role, is that the cabinets will need to be connected to the exchanges by optical fibre cables, which can transmit the huge amounts of data that people will want to download at the very high speeds necessary if many homes are to be connected. BT has not yet confirmed whether it is prepared to invest in laying fibre to outlying regions.
Dr Stephen Hornung is one of the team developing VDSL at BTexact, the telco's research arm based at Martlesham Heath. He agrees that technically VDSL could bring broadband to the countryside. "It offers higher penetration from the cabinet but whether that cabinet is fibred is an economic issue," he said.
Analysts agree. "Potentially it could be used if BT builds out fibre to villages," said Hamish MacKenzie of research firm IDC, but added: "As far as I know, though, they are not doing that yet."
According to MacKenzie, the price of fibre is dropping "very very quickly" -- to the extent that telco Redstone is thinking of bypassing DSL altogether and running fibre directly from telephone exchanges to homes. Whether UK telcos go down the VDSL route or favour fibre to the home, MacKenzie believes that widespread broadband access will still need government investment.
"In Sweden the government stumped up quite a lot of cash [for laying fibre]," he said. "The UK government was thinking about investing £1bn but rejected that in favour of a £30m fund to make broadband available in public places."
While MacKenzie does not think telcos should rely on government funding, he does believe that it could be the only way to achieve the ambitious targets set for broadband Britain by Labour. "By not going in that direction they are not helping themselves to achieve their target of everyone having access to broadband by 2005," he said.
Ovum analyst Tim Johnson agrees that VDSL could be a useful technology for getting broadband out to remoter parts of the UK. "It is definitely a good route for that and the economics for rural areas should be better," he said.
He also thinks that broadband in rural areas will need special funding, either from government, universal service obligations on telcos or from private individuals grouping together and agreeing to pay more. The latter would not go down too well among rural dwellers. "It wouldn't probably be very popular but then should we really be subsidising the Laird of Eniskillen to have broadband rolled out to his castle?"
Johnson is convinced that VDSL will become a mass market product and will eventually take over from ADSL, but not any time soon. "The day it totally replaces ADSL is still very remote," he said.
BT is not the only firm investing in VDSL. New Wheel Technology is also experimenting with it and, according to MacKenzie, has gone some way to solving the dual problem of speed and distance. "They are claiming to have achieved 54Mb/s over a distance of 3km," he said.
Currently the only operators offering a service is US-based Qwest. It is providing VDSL to 40,000 homes for a monthly subscription fee of around £25.
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