The NSW Office of State Revenue (OSR) collects about $14 billion a year and Linux plays a key part in it.
For OSR's CIO, Mike Kennedy, open systems are essential to providing agility in government.
OSR, like any government agency has to be able to deal with policy changes and decisions, which often have short lead times, Kennedy said.
"One of the things we have tried to do is use enterprise architecture to help us deal with those changes. The core pieces of our enterprise architecture are open source and commodity hardware-based approaches," he said.
"By having a more flexible approach in architecture, we've been able to adapt to a doubling of our staff, changes of location, and up to 300 percent increases in transaction volumes."
Kennedy said OSR uses commodity hardware (Dell Intel boxes) running Linux, which it has used for close to six years.
"We initially used Debian, however, three years ago we moved to RedHat to get better support," he said.
"While a lot of organizations start playing with Linux on the edge of the network, we started using it in electronic service delivery and running core business applications on it, so Linux is the core of our data centre," he said.
OSR also includes some proprietary products in its architecture.
"We use open source as one of our two server platforms and we probably have more open source than non-open source servers now. However, for our core databases, we actually use a proprietary database, which is Oracle, only because we couldn't find an open source solution at the time that suited all our needs," Kennedy said.
"So it isn't a mantra of 'open source and nothing else'; it is a mantra of what will give us the best business outcome."
Kennedy said that while technologists in the private sector can speak publicly about the "risks" they are taking because it may be seen as having a competitive edge, technologists in the public sector are much less likely to want to take risks or be seen to take risks.
"But the stigma of open source and the risk associated with it has largely gone now. All the big players like Oracle, IBM, HP and Fujitsu, are providing support for Linux now, so it's really a horses-for-courses decision," he said.
Kennedy will be speaking about 'Creating agility in government through use of open source and commodity hardware' at SEARCC 05 later this morning.
IDG is the official organizer and media sponsor of the SEARCC conference.