Novell is making it easier for Linux users to use content developed with Microsoft's Silverlight media framework.

The company today rolled out a new milestone release of Moonlight, its effort to bring Silverlight to Linux. The new Moonlight 2.0 beta adds critical new security and performance features to the release as it tracks Microsoft's ongoing development of Silverlight for Windows version 2 and 3.

Moonlight 1.0 officially debuted in February, while the first Moonlight 2 preview went public in May. With the Moonlight 2 beta, Novell is now declaring the release to be feature-complete, and the software now enters a bug-hunting and stability phase ahead of a general release.

"We're pleased that we've got this release only nine months after Microsoft Silverlight 2.0 went public, so we're not lagging that far behind," Miguel De Icaza, Novell Moonlight's project leader, told InternetNews.com. "We're feature-complete, and that means we pass all the Microsoft tests that they gave us -- those are tests for the graphical and audio components. We're coming out with this in beta, because this is the first time we're doing a broad release of Moonlight 2 and we're sure we'll run into bugs."

De Icaza added that he expects the bug-testing period to last two months, so a final Moonlight 2 will be available by the time of Microsoft's Professional Developers Conference (PDC) in November.

One of the biggest items added to Moonlight 2 beta since its May preview is a security-verification check to ensure that unauthorized code won't run.

"The verifier is the piece that ensures when you download a piece of code, that code won't do something illegal," De Icaza said.

The new verifier technology will also make its way upstream to Mono, Novell's effort to create a Microsoft .NET implementation on Linux, De Icaza said.

Microsoft's proprietary codecs

A key element of the Silverlight framework is its ability to handle high-quality video and audio codecs. Thanks to a deal worked out between Microsoft and Novell, Moonlight includes the Microsoft Media Pack, which is a set of proprietary codecs that Microsoft is making available to Moonlight users, free of charge.

As a result, the codecs installed through Moonlight are actually licensed by Microsoft, which in turn has licensed the video and codecs technology from its respective patent holders.

"Novell is not actually paying Microsoft for the codecs, and in a manner of speaking, Microsoft is footing the bill for the codecs," De Icaza said. "That being said, if people really don't want to use the binary codecs from Microsoft and they feel they don't need the license for the codecs, Moonlight can be compiled directly by end users, and users could choose to find an open source implementation of those codecs."

While proprietary codecs are part of Moonlight 2, Microsoft's Silverlight 3 includes some changes that make it more compatible with open source media codecs.

"In Silverlight 3, Microsoft added a fully pluggable media framework," De Icaza said. "So you could write a hook for open source Ogg Vorbis codec or other codecs. In Moonlight 2, we've already gone ahead and implemented the Silverlight 3 pluggable approach. So technically, Moonlight 2 is not a one-to-one match with Silverlight 2, it's somewhere in between Silverlight 2 and 3."

Microsoft released Silverlight 3 in July. As for when Moonlight 3 will hit development, De Icaza expects that the first Moonlight 3 preview will available by the time of Microsoft's PDC, just as Moonlight 2 hit general availability.