Update: If you're interested in Windows Vista Service Pack 1, be sure to read my new showcase, Inside Windows Vista Service Pack 1, which supplies more information and answers some of the questions raised in this preview. --Paul

With Windows Vista Service Pack 1 (SP1), now due in the first quarter of 2008, Microsoft is deemphasizing the role that service packs play in the ongoing updating and maintenance of its operating systems. That is, Vista SP1 will be a traditional service pack, collecting previously-issued updates into a single installation, and including few new end user features. It will, however, improve the Vista experience in a number of ways and include new device drivers and other improvements.

There are a number of reasons for this de-emphasis of service packs with Vista SP1. Most customers of Microsoft's latest OS releases have pervasive Internet connections and regularly update their systems automatically via the company's numerous online updating services, which we might collectively think of as Microsoft Update. (These services include Microsoft Update, Windows Update, Office Update, Automatic Updates, Windows Server Update Services, the Microsoft Download Center, and others.) And thanks to new updating mechanisms in Vista itself, Microsoft can drive improvements to customers more quickly than via service packs.

These improvements are delivered in a variety of ways and include such things as security updates, new versions built-in Vista applications (like Windows Mail/Windows Live Mail and Windows Photo Gallery/Windows Live Photo Gallery), new functionality (such as Windows Mobile synchronization via Windows Mobile Device Center), new and updated device drivers, and other system updates (such as the recently released Vista performance and reliability updates). Even Windows Ultimate Extras can be thought of as simply another avenue for deploying new features to Windows users. (Though of course the Extras are delivered via Windows Update.)

Improvements to Vista are driven by customer feedback and Vista's built-in (and opt-in) Windows Error Reporting (WER) tool and the related Customer Experience Improvement Program (CEIP) and Online Crash Analysis (OCA) services. Thanks to these tools, Microsoft and its hardware and software partners can drive the most-needed improvements directly back into Vista much more quickly than was possible in the past. Thus, as new drivers, security fixes, application compatibility fixes, and other software updates are delivered electronically to customers, Vista gets better and better over time. Previously, customers would have to wait for monolithic service packs, released irregularly and often over long periods of time, to get these improvements.

Microsoft points out two major and recent examples of these types of fixes, which have indeed dramatically improved the Vista experience. Earlier this month, the company issued two reliability and performance updates for Windows Vista. Had the company followed its deployment schedule for previous OS releases, Vista customers wouldn't have gotten these fixes until SP1.

What is Windows Vista SP1?

With that perfunctory background information out of the way, you're probably eager to find out what, exactly, is Windows Vista Service Pack 1. Certainly, there's cause for curiosity. Despite briefing me last year that Windows Vista SP1 would be released alongside Windows Server 2008 and would include a major kernel update, Microsoft subsequently launched a publicity campaign aimed at fooling customers into believing that the company hadn't yet even decided whether it would ever release SP1. Indeed, I sat and watched, twice, as Microsoft CEO Steve Ballmer publicly appeared confused about the mere mention of SP1, and he denied, both times, that the company was working on that release. The rationale for this decision, however dubious it may be, is that Microsoft was (and still is) quite concerned that its business customers will hold off on deploying Vista until SP1 is complete. That's because business customers have historically waited on the first service pack before deploying any major Microsoft OS release.

What's ironic about all this, of course, is that there's not much to say about SP1. After all the silence, evasiveness, and outright lies, Microsoft this week announced pretty much what I've been saying all along (which makes sense, since I got this information from the company in a one-on-one briefing): Yes, Windows Vista SP1 is in active development and will be released concurrently with Windows Server 2008, currently expected sometime in the first quarter of 2008. (There was no mention of the kernel update, however, so I'll keep digging.)

So here's what you can expect in Windows Vista SP1.

Quality improvements

As with previous Windows service packs, Windows Vista SP1 will include all of the previously released updates for Windows Vista, including all security, reliability, and performance improvements. Many of these improvements were driven by customer requests and the WER, as noted above.

Microsoft says it will make the following quality improvements in Vista SP1.

Security improvements include previously-announced changes to Windows Security Center that will allow third-party security software makers to more effectively communicate with and replace Microsoft's security dashboard with their own solutions, new APIs aimed at helping security software makers work with the Kernel Patch Protection feature in 64-bit versions of Vista (also previously announced), changes to RemoteApp and the Remote Desktop Protocol (RDP), the addition of a new Elliptical Curve Cryptography (ECC) pseudo-random number generator (PRNG), and a change to BitLocker Drive Encryption that adds optional multifactor authentication method combining keys protected by a TPM hardware module, a Startup Key stored on a USB memory key device, and a user-generated personal identification number.

Reliability. For reliability, Vista SP1 will include better reliability and compatibility with newer graphics cards, improved reliability when using notebook computers with an external display, improved networking configuration reliability, improved reliability of systems that are upgraded from XP to Vista, better compatibility with many printers, and increased reliability and performance when entering and resuming from sleep mode.

Performance. Vista SP1 adds a number of performance improvements as well by increasing the speed of copying and extracting files, increasing the performance of Hibernate and Resume, increasing the performance of domain-joined PCs when working offline from the domain, improving the performance of Internet Explorer (IE) 7 by reducing CPU utilization and speeding JavaScript parsing, improving battery life on certain mobile systems by reducing screen redraws and thus CPU utilization, increasing the performance of the CTRL+ALT+DEL logon dialog, and improving the performance of browsing network file shares.

Administrative improvements

Vista SP1 will include a number of changes aimed at the system administrators who deploy, support, and maintain Vista-based systems. These changes include:

BitLocker Drive Encryption. In the initial version of Vista, BitLocker could only automatically encrypt the C: drive. Now, in SP1, BitLocker can also optionally encrypt other drive volumes (D:, E:, and so on), as is possible with Windows Server 2008.

Terminal Service printing. Local printing from a Windows Terminal Services session will be improved.

Network Diagnostics. Windows Vista SP1 will add a new version of the Network Diagnostics tool that will also help administrators and end users diagnose common file sharing problems. (Available from the Diagnose and Repair link in Network and Sharing.)

Disk Defragmenter. The built-in Disk Defragmenter service will be updated so that customers can configure exactly which volumes are automatically defragged.

Group Policy. Vista SP1 will include a number of Group Policy (GP) changes. Most controversial, the Group Policy Management Console (GPMC) will be uninstalled so that the GPEdit management console can be used to manage local policies. Microsoft will also ship a tool before SP1 that will let admins add comments to Group Policy Objects (GPOs) and individual GP settings.

Support for new hardware and standards

Since Windows Vista shipped in early 2007, a number of emerging new hardware types and international standards have emerged. SP1 will address these changes by adding support for them to Windows Vista. They include:

Extended FAT (exFAT) file system. A future standard for flash memory storage and consumer-oriented mobile devices. Based on FAT, exFAT adds support for longer file names and other improvements.

Secure Digital (SD) Advanced Direct Memory Access (DMA). This update to SD technology improves transfer performance while decreasing CPU utilization. It will require SD DMA-compliant host controllers.

EFI network booting on x64 systems. In the initial shipping version of Windows Vista, 64-bit (x64) versions of the OS could boot on EFI-compliant PCs, which replace ancient BIOS technology with a more modern solution. With SP1, EFI-based x64 Vista systems can also support network boot, a feature that was previously available only on 32-bit (x86) Vista versions on BIOS-based PCs.

DirectX 10.1. Vista SP1 will support Microsoft's latest multimedia and gaming libraries.

Secure Socket Tunneling Protocol (SSTP). Vista SP1 will add support for the SSTP remote access tunneling protocol.

Other details about Vista SP1

As you can see reading through the list above, SP1 will not dramatically impact your day-to-day usage of Vista, though it will of course add many desirable low-level improvements. This is in keeping with Microsoft's traditional view of service packs, though nothing like Windows XP Service Pack 2 (SP2, see my review), which of course should be viewed as a major Windows release and not a simple service pack, despite the name. (Credit ex-Microsoft exec Jim Allchin for this: Mr. Allchin felt that Microsoft could have simply issued SP2 as a new version of Windows XP, but wanted to get it out to customers for free and thus decided to ship it as a service pack.)

What this means is that Vista SP1 will look, feel, and quack (er, ah, act) like a service pack. It will feature only minor changes to the Vista user interface, and will impact (in a negative sense) application compatibility in only minor ways as well. It will be a relatively small download--Microsoft estimates the Express download will be about 50 MB--when compared to the overall size of Vista. This 50 MB download is just 2 percent the overall size of Vista. (Windows 2000 SP4, at 15 MB, was about 3 percent the size of Windows 2000.)

Final thoughts

While Microsoft's continued requests for businesses to not wait for SP1 before deploying Windows Vista may seem self-serving, this week's revelations about the feature set of the service pack suggest that this advice is sound. Windows Vista SP1 looks like a solid and necessary update, but it will not dramatically impact the end user at all. If you're a Windows enthusiast, Vista SP1 is more a curiosity than something to get excited about. It will not include anything interesting or compelling, in an end user sense, such as a new Media Center version. (Which is also overdue, incidentally.) Hopefully, this will end the speculation. I only wish Microsoft had been this upfront about SP1 months ago. It's been a long time coming.