Internet service providers (ISPs) routinely overstate broadband speeds, and rarely provide anything near the advertised capabilities, according to new research by Ofcom.
The UK Broadband Speeds May 2010 research (PDF), conducted in partnership with broadband monitoring firm SamKnows, found that most packages hardly ever reach the 'up to' speed, although those on cable services fare better and Virgin Media is the most consistent performer.
Ofcom said that Virgin Media's 'up to 10Mbit/s' and 'up to 20Mbit/s' cable services offer twice the average download speeds of DSL, while its 'up to 50Mbit/s' cable service was the fastest service tested, delivering average download speeds of around 36Mbit/s.
Average broadband speeds in the UK have increased from 4.1Mbit/s to 5.2Mbit/s since April 2009, while 24 per cent now have speeds of over 10Mbit/s, up from eight per cent.
Jon James, broadband director at Virgin Media, used the announcement to attack the firm's rivals.
"It's clear that our DSL competitors aren't keeping up with promises of 20Mbit/s broadband. No DSL customer receives 18Mbit/s, and only two per cent receive over 14Mbit/s," he said.
"We need to ensure that people are not being ripped off, and the lack of transparency in broadband advertising risks damaging consumer confidence in superfast broadband."
BT, Virgin's main rival, defended its network, arguing that it gives customers "the most consistently accurate prediction of the speed specific to their line".
"We are investing in systems to make our predictions even better and to have them confirmed in writing," a spokesperson said.
BT also claimed that its £2.5bn investment in superfast fibre broadband will provide consumers and businesses with access to a better network than Virgin's.
"Our investment will deliver superior broadband to that offered by Virgin at a much cheaper price. Unlike Virgin's it will be open for other companies to use, and will be good news for the UK," the spokesperson said.
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