Linux: The forking fight-back

ISVs may be wary of fragmentation, but so far, LSB compliance hasn't come at the top of their list of priorities, says Carr. "They generally rank other issues, such as the development tool-chain, product support, features, and the overall ecosystem -- the presence of other ISVs and OEMs - first." This isn't as big a problem as it seems, he says, because Red Hat's close adherence to the specification guarantees a certain degree of LSB application support. "From a Red Hat viewpoint, we adhere to LSB standards and work closely with the LSB to drive the standards forward, keeping up with new developments in the open source community," he says. Still, Red Hat certification isn't the same as LSB compliance.

An initiative from several other Linux vendors is looking to eliminate the difference. The Linux Core Consortium (LCC), officially launched in November by a handful of major vendors, is collectively building a reference implementation of the LSB to be used as the core of all LCC members' operating systems. If LCC founder members Conectiva, Mandrakesoft, Progeny and Turbolinux have their way, an increasing number of Linux distributions will be based on a standard, LSB-compliant core. Linux makers such as Red Hat, SuSE and Debian have been invited to join, but are waiting to see the reference implementation before they commit.

The idea is that if an ISV certifies on an LCC-based Linux, it is practically identical to LSB certification. "All the applications that are certified against this reference implementation will be able to switch from one [OS] provider to another without doing anything," says Mandrakesoft chief executive Francois Bancilhon. "This is a strong enabler to the market."

If most Linux vendors are already agreeing to make their core technology meet LSB standards, the LCC argues, why not go a step further and use the same LSB implementation? "The need to differentiate is absolutely essential, but everybody agrees that this differentiation is in the top layer. There is a strong move toward convergence in the lower layers," says Bancilhon.

The group is learning from the mistakes of UnitedLinux, which commoditised both lower and upper layer software -- all UnitedLinux members' distributions were based on software licensed from SuSE, says Bancilhon. "One vendor controlled it, that was a mistake. Another was that they put the entire distribution in there. It should address only the commodity part of the technology," he says.

The LCC plans to deliver its first reference implementation in the coming months, and LCC-based distributions are due to arrive this year.

The FSG isn't standing still, either. Developments planned for the LSB this year include announcement of ISV support, more Linux vendor certifications, the first LSB certification lab in China, run by the Chinese government, obtaining ISO certification and perhaps most importantly, the release of the LSB 3.0.

The current LSB specification is a big improvement, but to stay relevant, the project must continue to evolve. "The LSB today covers only a part of what is needed for true compatibility and interoperability between different versions of Linux. It's an important step in the right directions but needs to be extended," says Intel's Hohndel. Key additions are more details around kernel extensions and APIs and ABIs higher up in the stack, for example around desktop environments or some managed runtimes.