WASAPI

Windows Vista (formerly codenamed Windows "Longhorn") has many significant new features compared with previous Microsoft Windows versions, covering most aspects of the operating system.

In addition to the new user interface, security capabilities, and developer technologies, several major components of the core operating system were redesigned, most notably 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.

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. Prior versions of Windows typically needed third-party wireless networking software to work properly; this is no longer the case with Windows Vista, as it includes comprehensive wireless networking support.

For graphics, Windows Vista introduces a new as well as major revisions to Direct3D. The new display driver model facilitates the new Desktop Window Manager, which provides the tearing-free desktop and special effects that are the cornerstones of the Windows Aero graphical user interface. The new display driver model is also able to offload rudimentary tasks to the GPU, allow users to install drivers without requiring a system reboot, and seamlessly recover from rare driver errors due to illegal application behavior.

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 can be used by data persistence services to enable atomic transactions. The service is being used to give applications the ability to work with the file system and registry using atomic transaction operations.

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