Analysts have 'reverse engineered' data from BT and come to the conclusion that the vast majority of British residents will never be able to get 24Mbps broadband direct to the home.

Research by broadband analysts Point Topic suggests that the bandwidth promised by some ISPs will not be available to most UK residents because they live too far from a telephone exchange.

"24Mbps is achievable within 300 metres of the exchange so you can get those speeds if you happen to live next door," said Julian Herbert, editor of the Point Topic UK Plus service.

"The further the signal has to travel, the lower the ultimate speed of the connection for the end user. In many cases we estimate that the signal has travelled through more than 700 metres of wire before it even leaves the exchange."

The analyst firm looked at BT's own data and worked out that less than 15 per cent of the UK population live within 2km of an exchange. Barely five per cent live close enough to get even 18Mbps downloads.

Delivery of 8Mbps is possible from around 3km, meaning that 45 per cent of the population would be capable of achieving such speeds.

The analyst said that links BT will not be able to provide high speed internet access to many customers without heavy investment in fibre links.