Oftel has defined the criteria for what constitutes broadband access.
The watchdog's Broadband Market Review states that a broadband service will now be defined as 'always-on' and having "a downstream capacity in excess of 256Kbps".
A government white paper on broadband previously defined broadband as a 1Mbps service.
Oftel took the decision to define the boundaries because of the number of different services on the market ranging from 128Kbps and up.
The report states: "In June 2002 the available internet access services were at 128Kbps [and below] and 512Kbps [and above].
"The director [of Oftel] chose not to specify more precisely the boundary for the start of broadband services within this range and, for the purposes of that direction, it did not need to do so.
"Since then the services provided or planned to be provided have changed slightly.
"In particular, the director is aware of services or planned services at 150Kbps and 256Kbps. These new services have required Oftel to be more specific about the boundary for broadband services between 128Kbps and 512Kbps.
"Given the availability of a 256Kbps broadband internet access product from Tiscali, the director currently considers that it is appropriate to define broadband internet access at speeds in excess of 256Kbps since the products currently available above this speed will allow different content such as streaming video to be delivered."
But although Oftel has set the 256Kbps boundary, it won't exclude 128Kbps and above services from being referred to as broadband, and will count them as broadband for statistical purposes.
The regulator claims that this allows the UK's broadband take-up to be compared with other European countries on a "like for like" basis.
It means that NTL's 128Kbps service, which will soon rise to 150Kbps, can still be advertised as broadband.
"NTL will be allowed to call this service broadband but it won't be allowed to call it high-speed broadband," said an Oftel spokeswoman.
But before anyone gets complacent and thinks that the definition has been settled, Oftel also warned that the goal posts may be shifted again "as new internet access services of different speeds are created and as new broadband content develops".
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