Major Linux vendors will today announce a standard Linux distribution to ensure that applications need only to be written once to run on all Linux implementations.

There have long been fears over the fragmentation of the Linux community, as happened with Unix in the early 1970s, because of the many flavours of the operating system.

Today's move is set to prevent a repeat situation while giving Linux more clout to compete against Windows. The announcement will also loosen Red Hat's grip on the market as the Linux distro with the greatest market share.

Gary Barnett, principal consultant with analyst Ovum, said: "This is of fundamental importance to the future of Linux and is extremely exciting.

"Companies such as IBM and Hewlett Packard [HP] have effectively made Linux into an increasingly viable alternative to Unix. So it will have very far-reaching ramifications in accelerating acceptance."

The Linux providers include Caldera, SuSE, TurboLinux and Connectiva. They will be joined by IBM, HP, Computer Associates, Intel and others in announcing what will be known as United Linux.

The release will not be limited to a common kernel, but will include a standard desktop, Gnome or KDE, networking applications and development tools such as the GNU C/C++ compiler and C library, sources said.

There will also be scope for companies like IBM and HP to provide lucrative value added services such as clustering and management.

Red Hat is missing from the list of leading Linux providers but Barnett thought that it would be forced to join in the near future to avoid losing market share. Although if it doesn't, United Linux will have more of a fighting chance in the marketplace.

More significantly, Sun Microsystems is missing from the systems vendors. The company has given some support to Linux but has not wholeheartedly embraced it.

"I would hope that Sun would respond quickly and positively to a united Linux, but I doubt it will. It seems over-wedded to Solaris and Sparc," said Barnett.

Sun recently bundled a Java 2 Enterprise Edition application server with Solaris. But J2EE itself is becoming a commodity and can be purchased at relatively low cost to run over Linux.