Sun mulls GPL 3 licence for Solaris

Sun Microsystems is considering a dual-licensing move that could raise tantalising possibilities of open source co-operation between Linux and Sun's Solaris operating system but legal issues complicate the possibility.

The server and software company is considering releasing Solaris under the forthcoming version 3 of the General Public Licence (GPL) in addition to the Community Development and Distribution Licence that currently governs the Unix variant, Sun president Jonathan Schwartz said in his blog Friday.

Schwartz said: "We want to do what we can to drive more efficiency and cross-pollination between Linux and OpenSolaris."

But there are legal barriers that could curtail sharing between different open-source software realms. Linux kernel project leader Linus Torvalds has said Linux will stay under the current version 2 of the GPL. That means that if Solaris is released under version 3, it's not necessarily the case that software from one project could be incorporated into the other.

Brian Ferguson, an intellectual-property attorney and BlackBerry customer at McDermott, Will & Emery, said: "If the two licences have differing terms, there may be a conflict between the two when you try to move back and forth. If we start fracturing off more and more with different licences, it becomes more of a legal landmine for everyone."

Schwartz publishes his musings on a public blog - and encourages his subordinates to do the same - in an attempt to restore the lustre, relevance and, ultimately, business strength of his company. Putting Solaris back in customers' minds is a key part of that blogging effort but Sun is employing other methods as well to regain ground Solaris lost to Linux in recent years. Sun is now emulating two factors in Linux's success by making Solaris open source software and bringing it to computers using x86 processors such as Intel's Xeon and AMD's Opteron.

Cross-pollination could be helpful for both operating systems. Linux could get some Solaris features - multithreading software, for example - while Solaris could benefit from Linux's relatively rich support for peripheral devices that plug into computers.

Torvalds oversees the Linux kernel, which is at the heart of the open source operating system generally called Linux. But many other components of the operating system under other programmers' control, including the GNOME user interface, are governed by the GPL and are outside Torvalds' jurisdiction.

Schwartz has criticised the GPL, arguing that its provisions make it difficult to mingle it with proprietary software projects. But he acknowledged in his blog that some Sun customers prefer it and said the GPL is the leading contender for the open source licence for its UltraSparc T1 "Niagara" processor.

He said: "We've yet to pick the open source licence under which the core intellectual property behind our multithreaded Niagara systems will ship, although we're biasing to GPL."

Also in his blog, Schwartz said HP is backing Solaris 10 for use on its ProLiant line of x86 servers. He wrote: "HP has joined ranks with IBM to support Solaris on their x64 platforms," leaving Dell the only top server maker without "a committed Solaris support plan".

Stephen Shankland writes for CNET News.com