Microsoft Windows 2000 (also referred to as Win2K or Windows NT 5.0) is a 32-bit graphical business-oriented operating system released on February 17, 2000 by Microsoft. Windows 2000 comes in four versions: Professional, Server, Advanced Server, and Datacenter Server. Additionally, Microsoft offers Windows 2000 Advanced Server, Limited Edition, released in 2001, which runs on Intel Itanium 64-bit processors.

Microsoft has replaced Windows 2000 Server products with Windows Server 2003, and Windows 2000 Professional with Windows XP Professional.

Windows 2000 has the reputation of being the most stable of the entire line of Microsoft operating systems after Windows NT 3.51.

Contents

1 Windows 2000 Core Features 1.1 NTFS5 1.2 Encrypting File System 1.3 Windows Driver Model 1.4 Graphical Improvements 2 Windows 2000 Desktop Features 3 Windows 2000 Server Features 3.1 Total Cost of Ownership 4 Criticisms 5 See also 6 External Links

Windows 2000 Core Features

All versions of Windows 2000 share certain features.

NTFS5

Version 3 of the NTFS, (also known as version 5.0), introduced quotas, file-system-level encryption (called EFS), sparse streams and reparse points, which are used to implement Directory Junctions, Volume Mount Points, Hierarchical Storage Management, Native Structured Storage and Single Instance Storage. By adding these features, Windows could compete with established file serving systems like Netware and Unix.

Encrypting File System

The Encrypting File System (EFS) introduced strong encryption into the Windows file world. It allowed any folder or drive to be encrypted and was transparent once implemented. As of February 2004, its encryption has not been compromised.

Windows Driver Model

Windows 2000 introduced the Windows Driver Model (WDM) driver model to the NT kernel. WDM is a multilayer driver model used to separate general functionality of devices from the specifics. For example, Microsoft may provide a standard USB driver that provides the basic functionality a USB device may use, such as raw bus protocol communication. The hardware vendor then only has to implement a driver that provides the functionality specific for whatever the device does. This can greatly simplify driver programming, and keeps programmers from introducing bugs every time a basic device protocol is reimplemented for a new product. Additionally, WDM drivers are theoretically compatible with any version of Windows supporting WDM (Win98, WinME, WinXP) regardless of the kernel. Drivers are the leading cause of instability in Windows, and WDM addresses this.

Graphical Improvements

Introduced in Windows 2000 was native alpha blending in GDI.

Windows 2000 Desktop Features

Windows 2000 Professional is designed as a desktop operating system in business environments. It offers greater security and stability than previous Windows desktop operating systems.

Windows 2000 Server Features

The various server products share the same user interface with Windows 2000 Professional, but contain additional components for running infrastructure and application software. A significant component of the server products is Active Directory, which is an enterprise-wide directory service based on LDAP. Additionally, Microsoft integrated Kerberos network authentification, replacing the often-criticised NT 4 authentification system. This also provided a purely transitive-trust relationship between Windows 2000 domains in a 'forest' (a collection of one or more Windows 2000 domains that share a common schema, configuration, and global catalog, being linked with two-way transitive trusts). Furthermore, Windows 2000 introduced a DNS server which allows dynamic registration of IP Adresses.

Total Cost of Ownership

Microsoft commissioned a firm to determine the total cost of ownership for enterprise applications on Windows 2000, such as security and other infrastructure tasks, and Web Serving. Windows 2000 had a lower TCO for the four infrastructure items (according to the report), but Linux had a lower TCO for web serving. There has been a lot of controversy over this claim, including:

• Claims that the test were done on different spec machines to give Microsoft an unfair advantage
• Claims that as Microsoft was paying for the report, the neutrality of it is in question

Criticisms

One aspect of concern with Windows 2000 (along with previous versions of NT), is the lack of an option to make a bootable DOS diskette. Unlike previous versions of Windows, which are based on DOS, (Windows 95, Windows 98, Windows Me), when running Windows 2000, a user is unable to make a bootable DOS diskette. While this is not a major issue for the average user, there are times when a DOS boot diskette is required (such as when doing a BIOS upgrade). In instances such as that, some users have turned to alternative sources for boot diskettes, such as BootDisk.com (http://www.bootdisk.com/).

An alternative to the bootable diskette is the Recovery Console. As diskettes are rapidly becoming obsolete, the main alternate boot device is the CD-ROM drive; users can access the Recovery Console when booting the install disc. The Recovery Console provides basic command-line functionality, including additional commands to enable and disable Windows services, among other things. The Recovery Console can also be installed onto an existing Windows 2000 installation to appear as an option on boot-up, making it easier to use than having to boot from a CD-ROM drive, but this isn't well documented by Microsoft.

Windows NT also introduced permissions for Registry editing. Windows 2000 incorporated both the Windows 9x REGEDIT.EXE program and NT's REGEDT32.EXE program. REGEDIT.EXE had a left-side tree view that began at "My Computer" and listed all loaded hives. REGEDT32.EXE had a left-side tree view, but each hive had its own window, so the tree displayed only keys. REGEDIT.EXE represented the three components of a value (its name, type, and data) as seperate columns of a table. REGEDT32.EXE represented them as a list of strings. REGEDIT.EXE was written for the Win32 API and supported right-clicking of entries in a tree view to adjust properties and other settings. REGEDT32.EXE was written for the NT 3.x API and required all actions to be performed from the top menu bar. Because REGEDIT.EXE was directly ported from Windows 98, it did not support permission editing (permissions do not exist on Windows 9x). Therefore, the only way to access the full functionality of an NT registry was with REGEDT32.EXE, which many considered to be inefficient and out-of-date. Windows XP was the first system to integrate these two programs into one, adopting the REGEDIT.EXE behavoir with the additional NT functionality.

History of Microsoft Windows

Windows: 1.0 | 2.0 | 3.x | NT | 95 | 98 | Me | 2000 | XP | Server 2003 | CE | Mobile | Longhorn | Blackcomb

See also

• Comparison of operating systems

External Links

• Official Page (http://www.microsoft.com/windows2000/)

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