Communications Minister Stephen Conroy has questioned the credentials of his opposite number Malcolm Turnbull.

When appointing Mr Turnbull as the Opposition's communications spokesman yesterday, Opposition Leader Tony Abbott pointed out that his colleague was chair of successful internet service provider OzEmail.

Mr Abbott tasked Mr Turnbull with "demolishing" the Government's $43 billion National Broadband Network (NBN) and he was quick to attack, claiming it is a waste of taxpayers' money.

"I am passionately in favour of broadband. I am a notorious internet junkie, and I love it," Mr Turnbull said.

"I've been involved in the internet since 1994 when we started OzEmail. So I'm very committed to it and I'm very committed to the amazing things that we can do with technology.

"But I'm also committed to not wasting tens of billions of dollars of taxpayers' money."

But Senator Conroy says the internet company Mr Turnbull was involved in used technology that predated broadband.

"Let's not overcook this cake here. Malcolm Turnbull was chairperson as a merchant banker of a dial-up company, so he was involved in a dial-up company," he said.

Senator Conroy has also fended off criticism over his decision to prioritise regional areas when building the NBN.

The Government promised to look at regional areas first as part of the deal to win the support of independent MPs Rob Oakeshott and Tony Windsor.

Senator Conroy has indicated the Government will sacrifice revenue by concentrating on the country.

But he says that has been part of the plan all along.

"There is no question that if you started 100 per cent in the capital cities you would get a faster revenue stream, but that would be unfair and inequitable," he said.

"We reject this concept that metro Australia deserves to have better broadband than regional and rural Australia."