February 2007

(Updated Feb 9 with some more context.)

One of the new features in Skype for Windows is the Extras Gallery. (Extras are third-party plug-ins that let users expand Skype functionality. See extras.skype.com for what’s available.) The Gallery is managed by a plug-in manager software framework developed by EasyBits Software and used under license.

The EasyBits software includes a form of digital rights management functionality intended to protect commercial software, such as plug-ins, from illegal redistribution or unlicensed use. Simply put, the EasyBits DRM framework helps us ensure compliance with software usage and distribution.

To enforce these license agreements, the EasyBits framework attempts to uniquely identify what physical computer it’s running on. One way to do this identification is to simply read the serial number of the motherboard, which is often available through a public query to the BIOS.

It is quite normal to look at indicators that uniquely identify the platform and there is nothing secret about reading hardware parameters from the BIOS. The function calls to do this are public and are available to any software running on your computer. Of course, in line with our Privacy Agreement, Skype does not retrieve any of this data. It is only used by the EasyBits software to ensure that plug-in use complies with the appropriate license token or key.

Since we learned that EasyBits DRM did not perform well on some newer platforms, we updated the version of their framework with one that no longer attempts to read from the BIOS. The current download of Skype for Windows, version 3.0.0.216, includes this updated framework.