How modular is Windows?
Is a stripped down version of Windows possible? In the Unsettling States' version of the antitrust trial (the full, unexpurgated version, as opposed to the DoJ's Antitrust Lite) Princeton University professor Andrew Appel argued this week that it is, basing his opinion on the existence of Windows XP Embedded.
XP Embedded is designed for use in cash registers, slot machines, ticket machines and the like, does not include Internet Explorer, and is described by Microsoft as "modular." From this, Appel extrapolates that XP Embedded's ability to have components removed and Microsoft's description of it as modular means that Windows XP itself must be modular. "I am of the opinion that the code underlying Microsoft's software platform products is most likely written in modular fashion... the modules serving to support Microsoft's middleware should be removable without causing disruption to the functionality of the remaining operating system."
This is however something of a leap of faith, because Microsoft's definition of words like modular and componentised is actually pretty limited. Modular means you can pull bits out and or disable them (which could be as prosaic as meaning it won't drive a printer), while componentised means modular, more or less. So you can forget any dreams you had about component-based plug and play operating systems. XP Embedded itself doesn't count as this, and although XP Embedded is a relation of XP itself, the latter will have sufficient differences and dependencies for it to be pretty tricky to disentangle at least some of the components.
That does not mean that Microsoft has not, as the Court of Appeals found, illegally commingled code in Windows, nor does it mean it shouldn't be compelled to pull them apart. Nor indeed does it mean that it wouldn't be a good idea if Windows was a proper modular, componentised OS. But it isn't. ®