Oftel believes that BT should cut its wholesale prices for unmetered internet access by 17 per cent and backdate the refund to December 2001.
The telecoms watchdog said that BT is still charging operators for certain call routing and call management measures that were originally put in place to stop its network being overloaded by unmetered internet traffic.
The cost for these measures was passed on ultimately to internet service providers and consumers, but Oftel has insisted that technological improvements mean that these measures are no longer necessary and have not been since December 2001.
In a statement announcing a consultative document, David Edmonds, director general of Telecommunications at Oftel, said: "When Oftel required BT to introduce a wholesale unmetered internet access product, BT introduced a number of additional measures to support the new service and which were included in the charge to other operators.
"BT has since made a number of improvements to its network, which means that the internet calls traffic can be processed without the additional measures."
Edmonds also said that when the savings are passed on to the operators, they in turn could pass these on to their customers, which could mean lower prices for unmetered internet access.
But vnunet.com has learned that any savings would be just a few pounds a year and may not be passed on to consumers.
An AOL spokesman said: "This is not a clear cut case and too soon to really comment on. Any refunds would go to the providers, such as Cable and Wireless, which sell on to us.
"If they passed the savings on to us it would only be pennies and not worth getting excited about."
BT said that it would be looking at the document but claimed that, if the measures went through as proposed, it would cost the telco between £10m and £15m a year.
"This is a complex area and we will be reading the document carefully," said a BT spokesman. "We hope that any decisions are made in the light of what the appropriate technical and financial impact could be."
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