Oftel is dropping its requirement that, in order to be classified as broadband, connections must be capable of delivering real-time video content.
The regulator decided this spring that 256Kbps was the minimum bandwidth capable of delivering video content, although ISPs argue that more is needed.
An Oftel spokeswoman told vnunet.com: "In our consultations with industry it became clear that the delivery of real-time video content was no longer seen as a requirement for broadband."
In its market review, to be published in November, Oftel has dropped the requirement that connections must be capable of delivering real-time video content in order to be classified as broadband.
The revised definition requires connections to be always-on, to handle telephony and data at the same time and offer "more bandwidth than dial-up connections".
"Not defining data speeds will not affect services," stated the spokeswoman.
But some ISPs disagree and fear that firms could end up buying 'broadband' that does not enable the applications they expect it to.
Video-conferencing and effective line sharing through Wi-Fi connections is not possible on lower bandwidth links.
David Rivington, strategy director at Bulldog Communications, suggested that, although the revision would "help the government achieve its stated goal of making broadband more widely available, some applications fundamentally require more [bandwidth]".
"Bulldog certainly considers video content delivery an important application," he added.
"Wi-Fi broadband also benefits from higher bandwidth services, such as 1Mbps or 2Mbps, and enhances the ability to share broadband access and the associated costs."
Applications like quality video conferencing require a minimum of 384Kbps upstream and downstream, according to Rivington. ADSL connections through BT's local loop offer less than 256Kbps upstream.
When broadband was first mooted, 2Mbps was considered, although efforts to reduce costs have resulted in 512Kbps largely being adopted as a UK standard.
This compares with 768Kbps in Germany, and 1.5Mbps in Japan. Under Oftel's revised terms, a 64Kbps line could qualify as 'broadband'.
BT said that it did not want to discuss Oftel's stance, but a spokesman stated: "512Kbps is the lowest service we market as broadband, but ultimately consumers will decide what broadband is."
The narrowest bandwidth currently marketed as broadband is 150Kbps, from ISP Tiscali and cable operator NTL.
Tim Johnson, chief analyst at broadband specialist Point Topic, insisted that broadband below 2Mbps cannot deliver on many of the promises made for the technology without better service guarantees.
"Below 2Mbps, it doesn't really matter whether it is 128Kbps, 512Kbps or 1Mbps," he said.
"What's important are contention ratios and service levels, and current ADSL is not really up to the job. It's quite sensible [for Oftel] to be a bit vague."
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