Open source is a state of mind, allowing users flexibility and control over their IT. So says Linux advocate IBM which has thrown its weight behind the open source operating system, investing $2bn so far and Linux-enabling all its hardware platforms.

The ability to access and modify source code gives the business a competitive advantage because it can react more quickly, according to IBM corporate technology strategist Mark Cathcart.

"The key thing is it gives the user flexibility. If there's a business opportunity, you simply hire programmers and get going," he explained. "You can be more competitive because your business can react quicker to changes in the market and the arrival of new technologies."

Access to source code means customers are no longer forced to go along with someone else's development plan. If the technology goes in a direction you aren't happy with, you can just programme in the changes you want, said Cathcart. "Because you can change code yourself, open source gives you a choice even if the technology goes in a different direction to the one you want."

Problems are fixed quicker because code can be examined by hundreds of people rather than just a handful of commercial programmers. "You can get problems fixed at whatever level you need and you don't have to wait for the vendor," he said.

Potential users often cite lack of support as their number one concern, but this is a misconception. "In the past year there has been a steady growth in commercial organisations that are offering commercial open source support contracts in the same way that a proprietary software company supports their software," explained Cathcart.

THE ARGUMENT AGAINST

No one is responsible for open source software, and that is its major drawback. Opensource sceptic Microsoft allows some of its biggest customers to see, but not change, Windows source code.

Most businesses don't want to be able to tinker with their operating system, according to Microsoft's .Net marketing manager Richard Hamblen.

"Ninety-nine per cent of people don't care - they just want to know it works. Most organisations want to focus on their core business and don't have the resources to support their platform," he explained.

Because no one owns the code of open source software, there is no guarantee that problems will be dealt with. "We own Windows and, if there's a bug, it's our responsibility to fix it. Who owns an open source operating system, and what onus is there to fix a problem?" he asked. "The open source model breaks down at the corporate level because nobody can take responsibility for it."

Hamblen is also doubtful whether a commercial company can guarantee support for software the customer has modified themselves. "The support company would have to go through thousands of lines of code to find out what changes had been made," he pointed out.

Linux advocates often point to price as a compelling advantage, but the price of a software licence is only one cost factor in a high-end deployment.

"How much does the lower cost of the operating system affect the actual cost of a solution? Expenses include support, hardware and deployment costs and application issues," said Hamblen. "Windows and Linux will co-exist because different users require different things."

A LINUX GURU EXPLAINS OPEN SOURCE

Alan Cox is up there with Linux creator Linus Torvalds in the hierarchy of open source software developers.

"From a business point of view, the biggest thing users get from open source is control - if you're running packaged software and the supplier decides to double the price, there's not a lot you can do about it," he said.

Here he explains five important facts that shed some light on what open source really means.

• Open source software is different from traditional proprietary software because users can access and alter the original source code. Software can be shared between users and there is less reliance on vendors.
• Open source and free software go back years before Linux. Linux is a significant piece of free software, but it's no more revolutionary than something like the Apache web server.
• Don't imagine that free software and open source software are necessarily the same. Free software is a product generally created by some kind of community and then released for general use, whereas open source is a technical term denoting that the source code is available.
• The GNU general public licence (GPL) is the licence originally written by the Free Software Association, requiring all code changes made by users to be contributed to the community. The Linux kernel is also governed by the GNU GPL.
• There is also a GNU Library GPL allowing for communication between open source software and existing proprietary software. People can run their Oracle databases on Linux, but changes to the Linux code must be given back.