Windows Vista

Windows Vista is a line of graphical operating systems used on personal computers, including home and business desktops, notebook computers, Tablet PCs, and media centers. Prior to its announcement on July 22, 2005, Windows Vista was known by its codename "Longhorn".[1] Development was completed on November 8, 2006; over the following three months it was released in stages to computer hardware and software manufacturers, business customers, and retail channels. On January 30, 2007, it was released worldwide to the general public,[2] and was made available for purchase and downloading from Microsoft's web site.[3] The release of Windows Vista comes more than five years after the introduction of its predecessor, Windows XP, making it the longest time span between two releases of Microsoft Windows.

Windows Vista contains hundreds of new features; some of the most significant include an updated graphical user interface and visual style dubbed Windows Aero, improved searching features, new multimedia creation tools such as Windows DVD Maker, and completely redesigned networking, audio, print, and display sub-systems. Vista also aims to increase the level of communication between machines on a home network using peer-to-peer technology, making it easier to share files and digital media between computers and devices. For developers, Vista includes version 3.0 of the .NET Framework, which aims to make it significantly easier for developers to write high-quality applications than with the traditional Windows API.

Microsoft's primary stated objective with Windows Vista, however, has been to improve the state of security in the Windows operating system.[4] One common criticism of Windows XP and its predecessors has been their commonly exploited security vulnerabilities and overall susceptibility to malware, viruses and buffer overflows. In light of this, Microsoft chairman Bill Gates announced in early 2002 a company-wide 'Trustworthy Computing initiative' which aims to incorporate security work into every aspect of software development at the company. Microsoft stated that it prioritized improving the security of Windows XP and Windows Server 2003 above finishing Windows Vista, thus delaying its completion.[5]

Windows Vista has been the target of a number of negative assessments by various groups. Criticism of Windows Vista has included protracted development time, more restrictive licensing terms, the inclusion of a number of new Digital Rights Management technologies aimed at restricting the copying of protected digital media, and the usability of other new features such as User Account Control.

Microsoft started work on their plans for Windows Vista ("Longhorn") in 2001, prior to the release of Windows XP. It was originally expected to ship sometime late in 2003 as a minor step between Windows XP (codenamed "Whistler") and "Blackcomb" (now known as Windows "Vienna"). Gradually, "Longhorn" assimilated many of the important new features and technologies slated for "Blackcomb," resulting in the release date being pushed back several times. Many of Microsoft's developers were also re-tasked with improving the security of Windows XP. Faced with ongoing delays and concerns about feature creep, Microsoft announced on August 27, 2004 that it was making changes. The original "Longhorn," based on the Windows XP source code, was scrapped, and Vista development started anew, building on the Windows Server 2003 codebase, and re-incorporating only the features that would be intended for an actual operating system release. Some previously announced features such as WinFS were dropped or postponed, and a new software development methodology called the "Security Development Lifecycle" was incorporated in an effort to address concerns with the security of the Windows codebase. After "Longhorn" was named Windows Vista, an unprecedented beta-test program was started, involving hundreds of thousands of volunteers and companies. In September 2005, Microsoft started releasing regular Community Technology Previews (CTP) to beta testers. The first of these was distributed among 2005 Microsoft Professional Developers Conference attendees, and was subsequently released to Microsoft Beta testers and Microsoft Developer Network subscribers. The builds that followed incorporated most of the planned features for the final product, as well as a number of changes to the user interface, based largely on feedback from beta testers. Windows Vista was deemed feature-complete with the release of the "February CTP," released on February 22, 2006, and much of the remainder of work between that build and the final release of the product focused on stability, performance, application and driver compatibility, and documentation. Beta 2, released in late May, was the first build to be made available to the general public through Microsoft's Customer Preview Program. It was downloaded by over five million people. Two release candidates followed in September and October, both of which were made available to a large number of users.

While Microsoft had originally hoped to have the operating system available worldwide in time for Christmas 2006, it was announced in March 2006 that the release date would be pushed back to January 2007, so as to give the company – and the hardware and software companies which Microsoft depends on for providing device drivers – additional time to prepare.

Through much of 2006, analysts and bloggers had speculated that Windows Vista would be delayed further, owing to anti-trust concerns raised by the European Commission and South Korea, and due to a perceived lack of progress with the beta releases. However, with the November 8, 2006 announcement of the completion of Windows Vista, Microsoft's most lengthy operating system development project came to an end.

Core technologies

Windows Vista is intended to be a technology-based release, to provide a solid base to include technologies, many of which will be related to how the system functions, and hence not readily visible to the user. An example of this is the restructuring of the architecture of the audio, print, display, and networking subsystems; while the results of this work will be visible to software developers, end-users will only see what appear to be evolutionary changes in the user interface.

Vista includes technologies such as ReadyBoost and ReadyDrive which employ fast flash memory (located on USB drives and hybrid hard disk drives respectively) to improve system performance by caching commonly-used programs and data. This manifests itself in improved battery life on notebook computers as well, since a hybrid drive can use the Flash memory to cache the data currently in use by the OS and/or other applications, spinning down the disc platters till some fresh data is required. Another new technology called SuperFetch utilizes machine learning techniques to analyze usage patterns in order to allow Windows Vista to make decisions about what application and content should be present in system memory at any given time.

As part of the redesign of the networking architecture, IPv6 has been incorporated into the operating system, and a number of performance improvements have been introduced, such as TCP window scaling. Windows Vista includes a more comprehensive support for Wireless Networks, compared to previous versions of Windows.

For graphics, Vista introduces a new Windows Display Driver Model, as well as major revisions to Direct3D. The new driver model facilitates the new Desktop Window Manager, which provides the tearing-free desktop and special effects that are the cornerstones of Windows Aero. WDDM's current version 1.0 is able to offload rudimentary tasks to the GPU, install drivers without requiring a system reboot and seamlessly recover from rare driver errors due to illegal application behavior. The next version is going to require an entirely new generation of GPUs, which nVidia and ATI are working on. Direct3D 10, developed in conjunction with major display driver manufacturers, is a new architecture with more advanced shader support, and allows the graphics processing unit to render more complex scenes without assistance from the CPU. It features improved load balancing between CPU and GPU and also optimizes data transfer between them.

At the core of the operating system, many improvements have been made to the memory manager, process scheduler, heap manager, and I/O scheduler. A Kernel Transaction Manager has been implemented that gives applications the ability to work with the file system and registry using atomic transaction operations.

Security-related technologies

Microsoft stated that security was a primary design goal for Vista. Microsoft's Trustworthy Computing initiative, which aims to improve public trust in its products, has had a direct effect on its development. This effort has resulted in a number of new security and safety features.

User Account Control is perhaps the most significant and visible of these changes. User Account Control is a security technology that makes it possible for users to use their computer with fewer privileges by default. This was often difficult in previous versions of Windows, as the previous "limited" user accounts proved too restrictive and incompatible with a large proportion of application software, and even prevented some basic operations such as looking at the calendar from the notification tray. In Windows Vista, when an action requiring administrative rights is requested, the user will be first prompted for an administrator name and password; in cases where the user is already an administrator, the user is still prompted to confirm the pending privileged action. User Account Control asks for credentials in a Secure Desktop mode, where the entire screen is blacked out, temporarily disabled, and only the authorization window is active and highlighted. The intent is to stop a malicious program 'spoofing' the user interface, attempting to capture admin credentials.

Internet Explorer 7's new security and safety features include a phishing filter, IDN with anti-spoofing capabilities, and integration with system-wide parental controls. For added security, ActiveX controls are disabled by default. Also, Internet Explorer operates in a "protected mode" which operates with lower permissions than the user and it runs in isolation from other applications in the operating system, preventing it from accessing or modifying anything besides the Temporary Internet Files directory. Microsoft's anti-spyware product, Windows Defender, has been incorporated into Windows, providing protection against malware and other threats. Changes to various system configuration settings (such as new auto-starting applications) are blocked unless the user gives consent.

Another significant new feature is BitLocker Drive Encryption, a data protection feature included in the Enterprise and Ultimate editions of Vista that provides encryption for the entire operating system volume. Bitlocker can work in conjunction with a Trusted Platform Module chip (version 1.2) that is on a computer's motherboard, or with a USB key.

A variety of other privilege-restriction techniques are also built into Vista. An example is the concept of "integrity levels" in user processes, whereby a process with a lower integrity level cannot interact with processes of a higher integrity level and cannot perform DLL–injection to a processes of a higher integrity level. The security restrictions of Windows services are more fine-grained, so that services (especially those listening on the network) have no ability to interact with parts of the operating system they do not need to. Obfuscation techniques such as address space layout randomization and Kernel Patch Protection are used to increase the amount of effort required of malware before successful infiltration of a system. Code Integrity verifies that system binaries haven’t been tampered with by malicious code.

As part of the redesign of the network stack, Windows Firewall has been upgraded, with new support for filtering both incoming and outgoing traffic. Advanced packet filter rules can be created which can grant or deny communications to specific services.

Business technologies

While much of the focus of Vista's new capabilities has been on the new user interface, security technologies, and improvements to the core operating system, Microsoft is also adding new deployment and maintenance features.

The WIM image format (Windows IMage) is the cornerstone of Microsoft's new deployment and packaging system. WIM files, which contain an image of Windows Vista, can be maintained and patched without having to rebuild new images. Windows Images can be delivered via Systems Management Server or Business Desktop Deployment technologies. Images can be customized and configured with applications then deployed to corporate client personal computers using little to no touch by a system administrator. ImageX is the Microsoft tool used to create and customize images.
Windows Deployment Services replaces Remote Installation Services for deploying Vista and prior versions of Windows.
Approximately 700 new Group Policy settings have been added, covering most aspects of the new features in the operating system, as well as significantly expanding the configurability of wireless networks, removable storage devices, and user desktop experience.
Services for UNIX has been renamed "Subsystem for UNIX-based Applications," and is included with the Enterprise and Ultimate editions of Vista. Network File System (NFS) client support is also included.
Multi-lingual User Interface - Unlike previous version of Windows which required language packs to be loaded to provide local language support, Windows Vista Ultimate and Enterprise editions supports the ability to dynamically change languages based on the logged on user's preference.
Wireless Projector support

Developer technologies

Windows Vista includes a large number of new application programming interfaces. Chief among them is the inclusion of version 3.0 of the .NET Framework, which consists of a class library and Common Language Runtime. Version 3.0 includes four new major components:

Windows Presentation Foundation is a user interface subsystem and framework based vector graphics, which will make use of 3D computer graphics hardware and Direct3D technologies. It provides the foundation for building applications and blending together application UI, documents, and media content. It is the successor to Windows Forms.
Windows Communication Foundation is a service-oriented messaging subsystem which will enable applications and systems to interoperate locally or remotely using Web services.
Windows Workflow Foundation provides task automation and integrated transactions using workflows. It is the programming model, engine and tools for building workflow-enabled applications on Windows.
Windows CardSpace is a component which securely stores digital identities of a person, and provides a unified interface for choosing the identity for a particular transaction, such as logging into a website.
These technologies will also be available for Windows XP and Windows Server 2003 to facilitate their introduction to and usage by developers and end users.

There are also significant new development APIs in the core of the operating system, notably the completely re-architected audio, networking, print, and video interfaces, major changes to the security infrastructure, improvements to the deployment and installation of applications ("ClickOnce" and Windows Installer 4.0), new device driver development model ("Windows Driver Foundation"), Transactional NTFS, mobile computing API advancements (power management, Tablet PC Ink support, SideShow) and major updates to (or complete replacements of) many core subsystems such as Winlogon and CAPI.

There are some issues for software developers using some of the graphics APIs in Vista. Games or programs which are built on Vista's version of DirectX, 10, will not work on prior versions of Windows, as DirectX 10 is not backwards-compatible with DirectX 9. According to a Microsoft blog, there are three choices for OpenGL implementation on Vista. An application can use the default implementation, which translates OpenGL calls into the Direct3D API and is frozen at OpenGL version 1.4, or an application can use an Installable Client Driver (ICD), which comes in two flavors: legacy and Vista-compatible. A legacy ICD, the kind already provided by independent hardware vendors targeting Windows XP, will disable the Desktop Window Manager, noticeably degrading user experience under Windows Aero. A Vista-compatible ICD takes advantage of a new API, and will be fully compatible with the Desktop Window Manager. At least two primary vendors, ATI and NVIDIA, are expected to provide full Vista-compatible ICDs in the near future. However, hardware overlay is not supported, because it is considered as an obsolete feature in Vista. ATI and NVIDIA strongly recommend using compositing desktop/FBOs for same functionality.

Visual styles

Windows Aero
Vista's premier visual style is built on a new desktop composition engine called Desktop Window Manager. Windows Aero introduces support for 3D graphics (Windows Flip 3D), translucency effects (Glass), live thumbnails, window animations, and other visual effects, and is intended for mainstream and high-end graphics cards. To enable these features, the contents of every open window is stored in video memory to facilitate tearing-free movement of windows. As such, Windows Aero has significantly higher hardware requirements than its predecessors. 128 MB of graphics memory is the minimum requirement, depending on resolution used. Windows Aero (including Windows Flip 3D) is not included in the Starter and Home Basic editions.
Windows Vista Standard
This mode is a variation of Windows Aero without the glass effects, window animations, and other advanced graphical effects such as Windows Flip 3D. Like Windows Aero, it uses the Desktop Window Manager, and has generally the same video hardware requirements as Windows Aero. This is the default mode for the Windows Vista Home Basic Edition. The Starter (developing markets) edition does not support this mode.
Windows Vista Basic
This mode has aspects that are similar to Windows XP's visual style with the addition of subtle animations such as those found on progress bars. It does not employ the Desktop Window Manager; as such, it does not feature transparency or translucency, window animation, Windows Flip 3D or any of the functions provided by the DWM. The Basic mode does not require the new Windows Display Driver Model (WDDM) for display drivers, and has similar graphics card requirements to Windows XP. For computers with graphics cards that are not powerful enough to support Windows Aero, this is the default graphics mode.
Windows Classic
An option for corporate deployments and upgrades, Windows Classic has the look and feel of Windows 2000 and Windows Server 2003, does not use the Desktop Window Manager, and does not require a WDDM driver. As with prior versions of Windows, this visual style supports "color schemes," which are a collection of color settings. Windows Vista includes six classic color schemes, comprised of four high-contrast color schemes and the default color schemes from Windows 98 and Windows 2000. Technology author Paul Thurrott noted Windows Vista's classic visual style "hides much of the useful new functionality that's available in other UI types," and that the "massive changes Microsoft made to Windows Explorer" also affect Windows Classic. Thurrott offers the opinion that Windows Vista's classic visual style is "horrible" and a "misbegotten excuse for a UI.