A componentized version of Windows XP SP2, Windows XP Embedded, has been updated to reduce its footprint and allow quicker OS builds, among other features. XP Embedded has proved useful for devices, such as point-of-sale terminals, that aren't power constrained and need to run unmodified Windows applications. The arrival of Windows Vista has obscured the roadmap for Windows XP Embedded, but Microsoft has revealed some future plans.

Feature Pack Improves Footprint, Tools

Windows XP Embedded consists of a complete version of Windows XP SP2 organized into a catalog of OS components that device designers can select for a specific device, and a developer tool called Target Designer that enables designers to build a custom OS image with those components. Windows XP Embedded also delivers a few unique components needed for specialized devices, such as components that support booting on devices with no graphics cards.

In general, any device built with Intel-architecture processors that could benefit from running unmodified Windows applications is a candidate for Windows XP Embedded. The product has been most widely employed on point-of-service (POS) terminals such as cash registers, and Microsoft now offers a special edition called Windows Embedded for Point-of-Service (WEPOS) for that usage. However, other devices have used Windows XP Embedded, including in-flight entertainment systems and thin-client terminals that run a local browser and media player.

The 2007 feature pack for Windows XP Embedded delivers minor updates, including the following:

• A more modular component catalog, which can reduce the footprint of OS images by as much as 20% over equivalent images, compared with the previous version
• Scripting support in Target Designer, enabling developers to automate builds of OS images
• Boot support for USB drives, which enables a technician to boot a known good configuration for a device from a USB drive for diagnostic purposes
• The ability to block writes to specific files via write filters on the file system, enabling a device to protect critical OS files.

Less Frequent Product Releases

Going forward, Microsoft plans to release the full Windows embedded product less frequently than it has in the past. Traditionally, a Windows OS release triggered a corresponding Windows embedded product release some three to six months later. Now, Microsoft intends to release feature packs with key new OS technologies while updating the embedded product less frequently. The near-term roadmap for Windows XP Embedded runs as follows:

Windows XP Embedded feature pack with Vista technology. Windows XP Embedded will get another feature pack with components that ship in Vista but also run on Windows XP SP2. Specifically, the feature pack will include Internet Explorer 7, Windows Media Player 11, and the Remote Desktop 6.0 client. The feature pack will be particularly important for manufacturers of thin-client terminals that want Vista-like capabilities for users. This feature pack might ship in mid-2007, although Microsoft has not announced any dates.

Windows Vista for Embedded Systems. When Windows Vista ships in Jan. 2007, Microsoft will announce special licensing terms for embedded device developers, enabling them to use the normal Vista OS and imaging tools to create specialized devices such as self-service kiosks.

Windows Vista Embedded. Microsoft plans to create an embedded product based on Windows Vista, analogous to Windows XP Embedded. However, it has not revealed any technical goals or plans for this release.

Microsoft says that more frequent feature packs, and fewer full embedded product releases, will enable it to get key new technologies (such as Internet Explorer 7) into developers' hands more quickly. However, some recent events might also have led Microsoft to scale back effort on the Windows embedded product. For one, Windows Vista has shipped with tools for OS image configuration very similar to those in Windows XP Embedded, weakening the case for a separate embedded product with specialized tools. In addition, Windows Embedded CE 6.0 has shipped with a new OS kernel that provides many of the capabilities of Windows XP Embedded. So while a Windows embedded product will be available for the foreseeable future, Microsoft might put less technical effort into the product and its tools.

Availability and Resources

Windows XP Embedded SP2 is available through authorized distributors. Customers purchase a license for each developer and a run-time license for each device that they build with the product. The developer license starts at US$995, while run-time licenses start at US$90 with discounts based on volume.

The Windows XP Embedded Web site is msdn.microsoft.com/embedded/windowsxpembedded/default.aspx.

The Windows XP SP2 Feature Pack 2007 Evaluation download is at www.microsoft.com/downloads/details.aspx?FamilyID=9BDF1DEA-A37E-4D25-83DF-AABBAA78914F.

The Windows XP Embedded team blog is blogs.msdn.com/embedded.

Windows Embedded CE 6.0 is outlined in "Embedded Kit Ships New Windows CE".

Recent embedded releases of Windows XP are explained in "Retail Embedded Software Updated" on page 14 of the Apr. 2006 Update and "Windows XP Embedded SP2 Released" on page 11 of the Jan. 2005 Update.