Criticism of Windows Vista
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Windows Vista, an operating system released by Microsoft in November 2006, has been criticized by reviewers and users. Due to issues with privacy, security, performance, driver support and product activation, Windows Vista has been the subject of a number of negative assessments by various groups.
Driver signing requirement
For security reasons, 64-bit versions of Windows Vista (and of Windows 7 as well) allow only signed drivers to be installed in kernel mode. Because code executing in kernel mode enjoys wide privileges on the system, the signing requirement aims to ensure that only code with known origin execute at this level. In order for a driver to be signed, a developer/software vendor will have to obtain an Authenticode certificate with which to sign the driver. Authenticode certificates can be obtained from certificate authorities trusted by Microsoft. Microsoft trusts the certificate authority to verify the applicant's identity before issuing a certificate. If a driver is not signed using a valid certificate or if the driver was signed using a certificate which has been revoked by Microsoft or the certificate authority, Windows will refuse to load the driver.
The following criticisms/claims have been made regarding this requirement:
- It disallows experimentation from the hobbyist community. The required authenticode certificates for signing Vista drivers are expensive and out of reach for small developers, usually about $400–500/year (from VeriSign).
Microsoft allows developers to temporarily or locally disable the signing requirement on systems they control (by hitting F8 during boot) or by signing the drivers with self-issued certificates or by running a kernel debugger.
At one time a third-party tool called Atsiv existed that would allow any driver, unsigned or signed to be loaded. Atsiv worked by installing a signed "surrogate" driver which could be directed to load any other driver, thus circumventing the driver signing requirement. Since this was in violation of the driver signing requirement, Microsoft closed this workaround with hotfix KB932596, by revoking the certificate with which the surrogate driver was signed.
Flaws in memory protection features
Security researchers Alexander Sotirov and Mark Dowd have developed a technique that bypasses many of the new memory-protection safeguards in Windows Vista, such as address space layout randomization (ASLR). The result of this is that any already existing buffer overflow bugs that, in Vista, were previously not exploitable due to such features, may now be exploitable. This is not in itself a vulnerability: as Sotirov notes, "What we presented is weaknesses in the protection mechanism. It still requires the system under attack to have a vulnerability. Without the presence of a vulnerability these techniques don’t really [accomplish] anything." The vulnerability Sotirov and Dowd used in their paper as an example was the 2007 animated cursor bug, CVE-2007-0038.
Microsoft engineer Jerry Markell noted upon the overall coding of the memory protection features lacked the necessary features for a decent run. Markell noted in his journal after taking a look at the issues that the code was "dangerously lacking, and, overall, pretty screwy." Markell submitted his complaints to one of his bosses later and received no message in return.
One security researcher (Dino Dai Zovi) claimed that this means that it is "completely game over" for Vista security. though Sotirov refuted this, saying that "The articles that describe Vista security as 'broken' or 'done for,' with 'unfixable vulnerabilities' are completely inaccurate. One of the suggestions I saw in many of the discussions was that people should just use Windows XP. In fact, in XP a lot of those protections we’re bypassing [such as ASLR] don’t even exist."
Digital rights management
Another common criticism concerns the integration of a new form of digital rights management (DRM) into the operating system, specifically the Protected Video Path (PVP), which involves technologies such as High-bandwidth Digital Content Protection (HDCP) and the Image Constraint Token (ICT). These features were added to Vista due licensing restrictions from the HD-DVD consortium and Blu-ray association. This will concern only the resolution of play-back of protected content on HD DVD and Blu-ray discs, but it has not been enabled as of 2012. A lack of a protected channel does not stop playback. Audio plays back as normal but high-definition video downsamples on Blu-ray and HD DVD to slightly-better-than-DVD quality video.
The Protected Video Path mandates that encryption must be used whenever content marked as "protected" will travel over a link where it might be intercepted. This is called a User-Accessible Bus (UAB). Additionally, all devices that come into contact with premium content (such as graphics cards) have to be certified by Microsoft. Before playback starts, all the devices involved are checked using a hardware functionality scan (HFS) to verify if they are genuine and have not been tampered with. Devices are required to lower the resolution(from 1920x1080 to 960x540) of video signals outputs that are not protected by HDCP. Additionally, Microsoft maintains a global revocation list for devices that have been compromised. This list is distributed to PCs over the Internet using normal update mechanisms. The only effect on a revoked driver's functionality is that high-level protected content will not play; all other functionality, including low-definition playback, is retained.
- Adding encryption facilities to devices makes them more expensive, a cost that is passed on to the user.
- If outputs are not deemed sufficiently protected by the media industry, then even very expensive equipment can be required to be switched off (for example, S/PDIF-based, high-end audio cards).
- Some newer high-definition monitors are not HDCP-enabled, even though the manufacturer may claim otherwise.
- The added complexity makes systems less reliable.
- Since non-protected media are not subject to the new restrictions, users may be encouraged to remove the protection in order to view them without restrictions, thus defeating the content protection scheme's initial purpose.
- Protection mechanisms, such as disabling or degrading outputs, may be triggered erroneously or maliciously, motivating denial-of-service attacks.
- Revoking the driver of a device that is in wide use is such a drastic measure that Gutmann doubts Microsoft will ever actually do so. On the other hand, they may be forced to because of their legal obligations to the movie studios.
Steve Gibson of Gibson Research Corporation has stated during his Security Now! show that he agrees with Peter Gutmann in principle and that what he proposes is a factually accurate description of what is found in the specification from Microsoft.
Reaction to criticism
Ed Bott, author of Windows Vista Inside Out, has published a three-part blog which rebuts many of Gutmann's claims.
Ed Bott's criticisms can be summarized as follows:
- Gutmann based his paper on outdated documentation from Microsoft and second-hand web sources.
- Gutmann quotes selectively from the Microsoft specifications.
- Gutmann did no experimental work with Vista to prove his theories. Rather, he makes mistaken assumptions and then speculates wildly on their implications.
- Gutmann's paper, while presented as serious research, is really just an opinion piece.
Technology writer George Ou states that Gutmann's paper relies on unreliable sources and that Gutmann has never used Windows Vista to test his theories.
Gutmann has responded to both Bott and Ou in a further article., which states that the central thesis of Gutmann's article has not been refuted and the response of Bott is "disinformation".
Microsoft has published a blog entry with "Twenty Questions (and Answers)" on Windows Vista Content Protection which refutes some of Gutmann's arguments.
- Microsoft is not to blame for these measures. The company has been forced to do this by the movie studios.
- The Protected Video Path will not be used for quite a while. There is said to be an agreement between Microsoft and Sony that Blu-ray discs will not mandate protection until at least 2010, possibly even 2012.
- Vista does not degrade or refuse to play any existing media, CDs or DVDs. The protected data paths are only activated if protected content requires it.
- Users of other operating systems such as Linux or Mac OS X will not have official access to this premium content.
Hardware requirements and performance
Much hardware that worked in XP does not work, or works poorly in Vista, due to companies going out of business, lack of interest in supporting old hardware, and changes in driver models. Service Pack 1 for Vista is said to fix many of these problems.
Tom's Hardware published benchmarks in January 2007 that showed that Windows Vista executed typical applications more slowly than Windows XP with the same hardware configuration. A subset of the benchmarks used were provided by Standard Performance Evaluation Corporation (or SPEC), who later stated that such "results should not be compared to those generated while running Windows XP, even if testing is done with the same hardware configuration." SPEC acknowledges that an apple-to-apples comparison cannot be made in cases such as the one done by Tom's Hardware, calling such studies "invalid comparisons." However, the TomsHardware report conceded that the SPECviewperf tests "suffered heavily from the lack of support for the OpenGL graphics library under Windows Vista". For this reason the report recommended against replacing Windows XP with Vista until manufacturers made these drivers available.
The report also concluded in tests involving real world applications Vista performed considerably slower, noting "We are disappointed that CPU-intensive applications such as video transcoding with XviD (DVD to XviD MPEG4) or the MainConcept H.264 Encoder performed 18% to nearly 24% slower in our standard benchmark scenarios". Other commonly used applications, including Photoshop and WinRAR, also performed worse under Vista.
Many low-to-middle-end machines that come with Windows Vista pre-installed suffer from exceptionally slow performance with the default Vista settings that come pre-loaded, and laptop manufacturers have offered to 'downgrade' laptops to Windows XP—for a price. However, this "price" is unnecessary, as Microsoft allows users of Windows Vista and Windows 7 to freely "downgrade" their software by installing XP and then phoning a Microsoft representative for a new product key. 
File operation performance
When first released in November 2006, Vista performed file operations such as copying and deletion more slowly than other operating systems. Large copies required when migrating from one computer to another seemed difficult or impossible without workarounds such as using the command line. This inability to efficiently perform basic file operations attracted strong criticism. After six months, Microsoft confirmed the existence of these problems by releasing a special performance and reliability update, which was later disseminated through Windows Update, and is included in Service Pack 1.
Nonetheless, one benchmark reported to show that, while improving performance compared to Vista's original release, Service Pack 1 does not increase the level of performance to that of Windows XP. However, that benchmark has been questioned by others within ZDNet. Ed Bott both questions his colleagues' methods and provides benchmarks that refute the results.
Early in Vista's lifecycle, many games showed a drop in frame rate compared to that experienced in Windows XP. These results were largely the consequence of Vista's immature graphics processing units drivers, and higher system requirements for Vista itself. Some recent benchmarks seem to suggest that, as of mid-2008, Vista SP1 is now on par with Windows XP in terms of game performance. However, game developers' recommended memory requirements on Vista are still higher (usually double) than on XP.
Concerns have been expressed that Windows Vista may contain software bloat. Speaking in 2007 at the University of Illinois, Microsoft distinguished engineer Eric Traut said, "A lot of people think of Windows as this large, bloated operating system, and that's maybe a fair characterization, I have to admit." He went on to say that, "at its core, the kernel, and the components that make up the very core of the operating system, is actually pretty streamlined."
Former PC World editor Ed Bott has expressed skepticism about the claims of bloat, noting that almost every single operating system that Microsoft has ever sold had been criticized as "bloated" when they first came out; even those now regarded as the exact opposite, such as MS-DOS.
Vista capable lawsuit
Two consumers sued Microsoft in United States federal court alleging the "Windows Vista Capable" marketing campaign was a bait and switch tactic as some computers originally installed with Windows XP could only run Vista Basic, and in some cases they did not run even Vista Basic at a user-acceptable speed. In February 2008 a Seattle judge granted the suit class action status, permitting all purchasers in the class to participate in the case. Released documents in the case, as well as a Dell presentation in March 2007, discussed late changes to Windows Vista which permitted hardware to be certified that would require upgrading in order to use Vista, and that lack of compatible drivers forced hardware vendors to "limp out with issues" when Vista was launched. This was one of several Vista launch appraisals included in 158 pages of unsealed documents.
Laptop battery life
With the new features of Vista, criticism has surfaced concerning the use of battery power in laptops running Vista, which can drain the battery much more rapidly than Windows XP, reducing battery life. With the Windows Aero visual effects turned off, battery life is equal to or better than Windows XP systems. "With the release of a new operating system and its new features and higher requirements, higher power consumption is normal", as Richard Shim, an analyst with IDC noted, "when Windows XP came out, that was true, and when Windows 2000 came out, that was true."
According to Gartner, "Vista has been dogged by fears, in some cases proven, that many existing applications have to be re-written to operate on the new system." Cisco has been reported as saying, "Vista will solve a lot of problems, but for every action, there's a reaction, and unforeseen side-effects and mutations. Networks can become more brittle." According to PC World, "Software compatibility issues, bug worries keep businesses from moving to Microsoft's new OS." Citing "concerns over cost and compatibility", the United States Department of Transportation prohibited workers from upgrading to Vista. The University of Pittsburgh Medical Center, said the rollout (of Vista) is significantly behind schedule because "several key programs still aren't compatible, including patient scheduling software."
As of July 2007, there were over 2,000 tested applications that were compatible with Vista. Microsoft has published a list of legacy applications that meet their "Works with Windows Vista" software standards as well as a list of applications that meet their more stringent "Certified for Windows Vista" standards. Microsoft has released the Application Compatibility Toolkit 5.0 application for migrating Vista-incompatible applications, while virtualization solutions like VirtualBox, Virtual PC 2007 or those from VMware can also be used as a last resort to continue running Vista-incompatible applications under legacy versions of Windows.
Microsoft also provides an Upgrade Advisor Tool (.NET must be installed and an Internet connection is required) which can be used on existing XP systems to flag driver and application compatibility issues before upgrading to Vista.
Removal of features from previous versions
Windows Vista was criticized by removing familiar Windows features and components. The Wikipedia article List of features removed in Windows Vista quite exhaustively covers the removals which were deemed unnecessary and unjustified.
Removal of announced features
Microsoft has also been criticized for removing some heavily discussed features such as Next-Generation Secure Computing Base in May 2004, WinFS in August 2004, Windows PowerShell in August 2005 (though this was released separately from Vista prior to Vista's release, and is included in Vista's successor, Windows 7), SecurID Support in May 2006, PC-to-PC Synchronization in June 2006. The initial "three pillars" in Vista were all radically altered to reach a release date.
Microsoft's international pricing of Vista has been criticized by many as too expensive. The differences in pricing from one country to another vary significantly, especially considering that copies of Vista can be ordered and shipped worldwide from the United States; this could save between $42 (€26) and $314 (€200). In many cases, the difference in price is significantly greater than was the case for Windows XP. In Malaysia, the pricing for Vista is at around RM799 ($244/€155). At the current exchange rate, United Kingdom consumers could be paying almost double their United States counterparts for the same software.
|“||Microsoft has come under fire from British consumers about the price it is charging for Vista, the latest version of Windows.||”|
Since the release of Windows Vista in January 2007 Microsoft has reduced the retail and upgrade price point of Vista. Originally Vista Ultimate was priced at $399. and Home Premium Vista at $239. These prices have since been reduced to $319 and $199 respectively.
Software Protection Platform
Vista includes an enhanced set of anti-copying technologies, based on Windows XP's Windows Genuine Advantage, called Software Protection Platform (SPP). In the initial release of Windows Vista (without Service Pack 1), a major component of this was a reduced-functionality mode, which is entered when it is detected that the user has "failed product activation" or that their copy is "identified as counterfeit or non-genuine." The technology was described in a Microsoft white paper as follows:
|“||The default Web browser will be started and the user will be presented with an option to purchase a new product key. There is no start menu, no desktop icons, and the desktop background is changed to black. [...] After one hour, the system will log the user out without warning.||”|
This was criticised for being overly draconian, especially given an imperfect false-positive record on behalf of SPP's predecessor, and at least one temporary validation server outage which reportedly flagged many legitimate copies of Vista and XP as "Non-Genuine" when Windows Update would "check in" and fail the "validation" challenge.
SPP was significantly altered in Windows Vista Service Pack 1. Instead of the reduced functionality mode, an installation of Vista left unactivated for 30 days presents the user with a nag screen prompting them to activate the operating system when they log in, changes the desktop to a solid black colour every hour, and periodically warns the user about software counterfeiting with notification balloons. In addition, updates classified as optional are not available to unactivated copies of Vista. Microsoft maintains a technical bulletin providing further details on product activation for Vista.
Windows Ultimate Extras
Windows Vista Ultimate users can download exclusive Windows Ultimate Extras. These extras have been released much more slowly than expected, with only four available as of August 2009, almost three years after Vista was released, which has angered some users who paid extra mainly for the promised add-ons. Barry Goffe, Director of Windows Vista Ultimate for Microsoft states that they were unexpectedly delayed on releasing several of the extras, but that "Microsoft plans to ship a collection of additional Windows Ultimate Extras that it is confident will delight its passionate Windows Vista Ultimate customers."
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