By August there should be "frenetic" activity to make decisions about the technology infrastructure, undoubtedly the most challenging part of the project.

Executive director of the University of NSW's Cyberspace Law and Policy Centre, David Vaile is one of the most vocal critics of the government's projections, telling Computerworld the A$1 billion, 18-month figures touted by Hockey are "unrealistic" for an IT project of this scale. Vaile believes the project's cost could blow out as far as A$5 billion.

But Hockey stood his ground and cited process efficiency as another significant cost saver.

"Every time people front-up to a Centrelink office they spend an average of between 90 seconds and three minutes proving who they are before the interaction begins," he said. "This is a cumbersome way of running Human Services."

While conceding the optimal service delivery model would be Internet-based, Hockey said as many Australians not Net-connected, a "mezzanine model" was agreed on to take Australia from a "technology stone age" to a more modern, simpler form of interaction.