The BBC is to begin showing all its programmes live over the internet from next week, raising questions about the long-term viability of the licence fee.

Critics said that although viewers would still need to buy a licence to watch programmes on their computers, it would become harder to ensure payment. There are also questions over whether the telephone network could cope with the expected rise in internet traffic.

Sir Howard Davies, the director of the London School of Economics, who sat on a committee reviewing the future of the licence fee at the beginning of the decade, said: “What are they going to do? Seize your computer and look through your history? Can you imagine the licensing people doing that level of enforcement?”

The corporation, which already makes digital channels such as BBC Three and BBC Four available online, announced yesterday that it would complete the picture by making BBC One and BBC Two available from next Thursday.

Watching television programmes over the internet has taken off in the past year since the introduction of the BBC’s catchup service, the iPlayer, which enables viewing of material broadcast in the previous seven days.

Since its launch on Christmas Day last year, some or all BBC programmes have been watched 250 million times. EastEnders, watched by an average of 18.9 million at least once a month on broadcast television, was watched 457,000 times on the iPlayer last month.

The corporation believes that viewing over the internet will not be enough to persuade the public to get rid of their televisions. A spokesman said that the BBC wanted to “offer our licence fee-payers more choice and flexibility” and that the broadcaster “fully expects this to supplement, rather than replace, viewing via traditional broadcast to a television”.

In total 25.3 million households pay the television licence, generating £3.37 billion for the BBC. However, one in 20 households dodges the levy, despite an aggressive enforcement campaign in which viewers are told that the list of nonpayers are “all in our database”.

A television licence is required “irrespective of what device you are using – television, computer, laptop, mobile phone or any other – and how you receive programmes, whether by satellite, cable, via the internet or any other way,” according to TV Licensing, the body that collects the fee. It also pays for BBC radio.

There are concerns about the impact that a surge in online viewing could have on the way the internet functions.

Francesco Caio, who conducted a review into the future of the network for the Government this year, believes that there could be medium-term problems because of the extra capacity required for live television.

Mr Caio said: “Online television does not cause any capacity issues for the moment but in three to five years’ time there could be problems that will particularly affect areas of dense population.”

A spokeswoman for Tiscali, the fourth-biggest internet provider, said: “If you download a television programme, it can be done efficiently, in between other network traffic, but streaming a video [showing live before it is completely downloaded] takes up a set amount of capacity – about 300 kilobits a second.” Tiscali believes that broadcasters could pay more to prioritise their content to run smoothly over the internet, although the BBC has shown little willingness to pay.

Mr Caio said that the unwillingness of broadcasters to pay would more likely lead to the cost being borne by consumers through an increased monthly subscription.

“Broadband prices have been falling but I think we could get to the point where the need for investment means that prices of telephone and internet services will start heading north,” he said.

Jana Bennett, the director of BBC Vision, said: “The launch of BBC One and BBC Two online completes our commitment to make our portfolio of channels available to watch on the internet.”

Formally, the BBC plans to run the online broadcasts of its two principal channels for a year but it is unlikely to abandon the experiment.

In any event it has little choice because existing rules mean that any website can transmit the two channels, plus ITV1, Channel 4 and Five, if they have the right technology.

Online broadcasting is also likely to be a boon for technologically sophisticated expatriates and other viewers who do not pay the licence fee.

Although the BBC, like other broadcasters, tries to ensure that its content can be watched only in the United Kingdom, it is possible to buy software that covers up a web surfer’s location, making them appear to be watching in Britain even when they are not.

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