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21CN: the 21st century nightmare?

Posted on 16 Jun 2008 at 16:56

When PC Pro challenged BT on the wide discrepancy between its published labs results and Rejali's statement, a spokesman claimed: "Customers that today take the DSL Max service (up to 8Mb/sec) are receiving higher line speeds than were predicted during the DSL Max trial, hence this comment that 50% of UK households could well achieve higher speeds than the current lab trial data indicates. It will not be until sufficient services are run over the live network that line speeds can be accurately predicted across the UK."

Yet, those close to the BT 21CN trials are also pessimistic about potential speeds. "Not many people are going to get anywhere near 24Mb/sec," said James Blessing of Entanet, one of the ISPs that has worked closely with BT on 21CN testing. He says speeds in the range of 10-14Mb/sec are more realistic. "If you're getting above four meg [currently] you'll see an increase. If you're getting below four meg, some people might get a slight decrease."

Why? Because ADSL2+ continues to lose speed rapidly the further you live from the local exchange. And with faster headline speeds, the difference between those at the top end and those at the bottom becomes even more marked. "People may well see more variation," said Andrew Ferguson, editor of Thinkbroadband.com.

The Sky-owned ISP, UK Online, has been offering ADSL2+ on its local loop unbundled services for some time, and it refuses to sell the service based on the maximum headline speed because it's so misleading. "Not a lot of people can get the very top speed," said the company's senior product manager Josh Morse. "We find 16Mb/sec is a speed a lot of people can get and it's a stable speed. We used to sell at 22Mb/sec; we've now come down to 16Mb/sec."

Aware of the backlash it's suffered on ADSL Max, even BT Wholesale is imploring ISPs not to focus on the maximum figure when selling to consumers. "Headline speeds still seem to be the key marketing lever," Guy Bradshaw, BT Wholesale's general manager, said recently. "As an industry, we should focus on average throughput." Although BT Retail - the division of BT responsible for selling connections to consumers - refused to say how it would market 21CN-based broadband at the time of going to press.

Will ISPs resist the temptation to advertise the headline speeds? Fat chance, say industry watchers. "They won't listen," said Ferguson. "It's such a nice marketing thing. The LLU providers [who are already on ADSL2+] haven't held back from 'up to 16Mb/sec' and 'up to 24Mb/sec'". Sam Crawford, the man behind the SamKnows Broadband site, agrees. "A couple of ISPs have announced [BT] Wholesale connection plans and the first thing they say is 24 megs! Everyone has to go for the best possible scenario for themselves, or they'll lose out." Unless, of course, Ofcom or the Advertising Standards Authority decide to take a stand...

Bandwidth on-demand

One of the less-publicised (and perhaps most disturbing) consequences of the new network is that BT will be offering different tiers of bandwidth, or "quality of service" options, as BT Wholesale puts it. These are:

Real Time This is the maximum possible bandwidth available on a line, where the customer doesn't necessarily need to guarantee every packet of data arrives but wants them to arrive as fast as possible. This option will be of most interest to gamers seeking minimum latency, those looking to run business VoIP services, videoconferencing and other "real-time" events.