AS BBC director general Mark Thompson recently announced plans to reduce the size of the corporation, placing up to 2,500 jobs at risk, the future of public sector broadcasting in the UK hangs in the balance.

The cuts - said to be centred on BBC News and Factual TV, which makes programmes such as Planet Earth and Top Gear - will be imposed over the next six years, although no specific programmes have been targeted.

Sir Michael Lyons, chairman of the BBC Trust, the governing body which approved the plans, said the plans are aimed at plugging a £2 billion funding shortfall and could make or break the corporation.

The BBC was constitutionally established in 1922 by a Royal Charter, renewable every 10 years, with an accompanying agreement to recognise its editorial independence and set out its obligations to public service broadcasting.

The latest charter came into effect on January 1 this year.

But with unions bristling at the prospect of compulsory redundancies, the threat of strike action is expected before Christmas and many media commentators have expressed concern over the future of public service broadcasting in this country.

"There's a wonderful pamphlet from the 1930s in which the BBC's founder Lord Reith said the BBC believes it should make programmes that are slightly better than the public wants," says Bournemouth University Professor of Radio and freelance broadcaster Sean Street.

"That sounds terribly patronising, but when you think about it, it is what the BBC stands for - wanting to be challenging.

"In radio terms it is always said that radio should surprise, which is what happens when you have a difference between licence-funded broadcasting and commercial broadcasting, which is programmed to a defined audience to attract advertising and, of course, newer technology like MP3 players, which we programme ourselves and therefore can't surprise us.

"The argument is that a commercialised BBC would not be able to break new music or make minority appeal programmes that you can return to through podcast services for instance. Where else would you hear a discussion about the divine right of kings but on Melvyn Bragg's In Our Time programme on Radio 4?

"You can't digest it all in one go, but you can download the podcast and perhaps the future of the BBC lies in those new technologies."

In August, BBC Newsnight presenter Jeremy Paxman called on media executives to come up with "greater purpose, or moral drive" for television, rather than chasing ratings.

The much publicised scandals over rigged phone-ins, doctored documentary footage and fraudulent competitions have rocked public confidence in television.

And yet the BBC is still widely regarded as the yardstick for news gathering.

"I'm sure there will still be a BBC in 10 years' time, but it will be slimmer, more focused and still the standard by which other news operations are judged," says Tom Watson, deputy dean of Bournemouth University's Media School.

"It will achieve this by converging its separate operations for television, radio, online and print.

"From an educator's point of view, the audience has already converged its perception of different media - when we interview prospective students they don't differentiate between the web, print, MP3 players, podcasts, radio or television.

"The BBC should concentrate on quality and play to its strengths. For instance, John Peel was able to innovate and challenge his audience in life-changing ways because he worked for a public service broadcaster, but if the BBC goes after ratings with wall-to-wall reality TV pap, it fails."

Some sections of the BBC have already been effectively commercialised, says Sean Street who points to the predominance of BBC productions shown on cable/satellite channels such as UKTV Gold.

"We live in a kind of permanent present at the moment of extraordinary technological advances. In five or six years' time we will have broadband available on mobile devices so the way programmes are delivered and watched or listened to will change again.

"But it's worth remembering that if you are in Tewkesbury and the flood waters are rising, you won't be logging on to the internet to find out what's going on, you'll be hoping there are batteries in the transistor radio so you can tune into the BBC for news."