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In information technology, a server is an application or device that performs services for connected clients as part of a client-server architecture. A server application, as defined by RFC 2616 (HTTP/1.1), is "an application program that accepts connections in order to service requests by sending back responses." Server computers are devices designed to run such an application or applications, often for extended periods of time with minimal human direction. Examples of d-class servers include web servers, e-mail servers, and file servers. Image File history File links Question_book-3. ... Image File history File links Broom_icon. ... Image File history File linksMetadata Size of this preview: 800 × 533 pixel Image in higher resolution (3504 × 2336 pixel, file size: 980 KB, MIME type: image/jpeg) This is a picture taken of my web server in 2005. ... For other uses, see IBM (disambiguation) and Big Blue. ... Sun Microsystems, Inc. ... The Hewlett-Packard Company (NYSE: HPQ), commonly known as HP, is a very large, global company headquartered in Palo Alto, California, United States. ... Apple Inc. ... Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ... This article is about the corporation Dell, Inc. ... It has been suggested that X5DA8 be merged into this article or section. ... Information and communication technology spending in 2005 Information technology (IT), as defined by the Information Technology Association of America (ITAA), is the study, design, development, implementation, support or management of computer-based information systems, particularly software applications and computer hardware. ... Client/Server is a network application architecture which separates the client (usually the graphical user interface) from the server. ... HTTP (for HyperText Transfer Protocol) is the primary method used to convey information on the World Wide Web. ... The inside/front of a Dell PowerEdge web server The term Web server can mean one of two things: A computer program that is responsible for accepting HTTP requests from clients, which are known as Web browsers, and serving them HTTP responses along with optional data contents, which usually are... A mail transfer agent or MTA (also called a mail transport agent, message transfer agent, mail server, or a mail exchanger (MX) in the context of the Domain Name System) is a computer program or software agent that transfers electronic mail messages from one computer to another. ... This article or section does not cite its references or sources. ...

Term usage in information technology

Server is an adjective in the term server operating system. A server operating system is intended, enabled, or better able to run server applications. The differences between the server version and the "workstation" version of an operating system vary. Sometimes (as in the case of Windows 2000 and Windows 2000 Server), the primary difference is the removal of arbitrary license-dependent limits on the number of network file share connections accepted. Some server editions include additional server applications bundled with the operating system. Some server applications (e.g. Microsoft IIS) impose arbitrary limits on the number of HTTP connections they will accept, depending on whether they are running under a server operating system or not. Windows 2000 (also referred to as Win2K) is a preemptive, interruptible, graphical and business-oriented operating system designed to work with either uniprocessor or symmetric multi-processor computers. ... Microsoft Internet Information Services (IIS, formerly called Internet Information Server) is a set of Internet-based services for servers using Microsoft Windows. ...

A server computer (often called server for short) is a computer system that has been designated for running a specific server application or applications. A computer that is designated for only one server application is often named for that application. For example, when Apache HTTP Server (software) is a company's web server, the computer running it is also called the web server. Server applications can be divided among server computers over an extreme range, depending upon the workload. Under light loading, every server application can run concurrently on a single computer. Under heavy loading, multiple server computers may be required for each application. Under medium loading, it is common to use one server computer per server application, in order to limit the amount of damage caused by failure of any single server computer or security breach of any single server application. Any server computer can also be used as a workstation, but it is avoided in practice, again to contain risk. The Apache HTTP Server, commonly referred to simply as Apache, is a web server notable for playing a key role in the initial growth of the World Wide Web. ...

Server or server computer is also a designation for computer models intended for use running server applications, often under heavy workloads, unattended, for extended time. While any "workstation" computer can run server operating systems and server applications, a server computer usually has special features intended to make it more suitable. Distinctions often include faster processor and memory, more RAM, larger hard drives, higher reliability, redundant power supplies, redundant hard drives (RAID), compact size and shape, modular design (e.g., blade servers often used in server farms), rack or cabinet mountability, serial console redirection, etc. IBM HS20 blade server. ... A typical server farm. ... Rack-mounted redirects here. ... Wikipedia servers installed in a server cabinet. ... Knoppix system console showing the boot process The system console, root console or simply console is the text entry and display device for system administration messages, particularly those from the BIOS or boot loader, the kernel, from the init system and from the system logger. ...

The name server or server appliance also applies to network-connected computer appliances or "appliance hardware" that provides specific services onto the network. Though the appliance is a server computer, loaded with a server operating system and a server application, the user need not configure any of it. It is a black box that does a specific job. The simplest servers are most often sold as appliances, for example switches, routers, gateways, print servers, net modems. Computer appliance are software devices that provide a narrow range of functions that are generally run on a hardware platform of their own. ... This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ...

A server is defined as a multiuser computer that provides a service (e.g. database access, file transfer, remote access) or resources (e.g. file space) over a network connection.

Server hardware

Although servers can be built from commodity computer components—particularly for low-load and/or non-critical applications—dedicated, high-load, mission-critical servers use specialized hardware that is optimized for the needs of servers.

A server rack seen from the back

For example, servers may incorporate “industrial-strength” mechanical components such as disk drives and computer fans that provide very high reliability and performance at a correspondingly high price. Aesthetic considerations are ignored, since most servers operate in unattended computer rooms and are only visited for maintenance or repair purposes. Although servers usually require large amounts of disk space, smaller disk drives may still be used in a trade-off of capacity vs. reliability. Image File history File links Download high-resolution version (512x768, 130 KB) William Viker <william. ... Image File history File links Download high-resolution version (512x768, 130 KB) William Viker <william. ... Disk Drive is the afternoon show on CBC Radio Two. ... A set of 4 industry standard 80mm fans, most commonly used in personal computers. ...

CPU speeds are far less critical for many servers than they are for many desktops. Not only are typical server tasks likely to be delayed more by I/O requests than processor requirements, but the lack of any graphical user interface (GUI) in many servers frees up very large amounts of processing power for other tasks, making the overall processor power requirement lower. If a great deal of processing power is required in a server, there is a tendency to add more CPUs rather than increase the speed of a single CPU, again for reasons of reliability and redundancy. GUI redirects here. ...

The lack of a GUI in a server (or the rare need to use it) makes it unnecessary to install expensive video adapters. Similarly, elaborate audio interfaces, joystick connections, USB peripherals, and the like are usually unnecessary.

Because servers must operate continuously and reliably, noisy but efficient and trustworthy fans may be used for ventilation instead of inexpensive and quiet fans; and in some cases, centralized air-conditioning may be used to keep servers cool, instead of or in addition to fans. Special uninterruptible power supplies may be used to ensure that the servers continue to run in the event of a power failure. The term air conditioning most commonly refers to the cooling and dehumidification of indoor air for thermal comfort. ... An uninterruptible power supply (UPS), also known as an uninterruptible power source or a battery backup is a device which maintains a continuous supply of electric power to connected equipment by supplying power from a separate source when utility power is not available. ...

Typical servers include heavy-duty network connections in order to allow them to handle the large amounts of traffic that they typically receive and generate as they receive and reply to client requests.

The major difference between servers and desktop computers is not in the hardware but in the software. Servers often run operating systems that are designed specifically for use in servers. They also run special applications that are designed specifically to carry out server tasks. An operating system (OS) is the software that manages the sharing of the resources of a computer and provides programmers with an interface used to access those resources. ...

Servers have a unique property where the more powerful and complex the system, the longer it takes for the hardware to turn on and begin loading the operating system. Servers often do extensive pre-boot memory testing and verification, along with starting up remote management services. The hard drive controllers then start up banks of drives in sequence so as not to overload the power supply with the sudden surge of everything turning on at once, then followed by RAID system prechecks for correct operation of redundancy. It is not uncommon for all these preboot hardware checks to take several minutes, but then for the machine to run continuously for over a year of uptime. For other uses, see Raid. ... Uptime is a measure of the time a computer system has been up and running. ...

Server operating system

Some popular operating systems for servers—such as FreeBSD, Solaris, and Linux—are derived from or similar to the UNIX operating system. UNIX was originally a minicomputer operating system, and as servers gradually replaced traditional minicomputers, UNIX was a logical and efficient choice of operating system for the servers. However, the market share of the Windows Server product line has been growing steadily, and has become the new top server operating system in revenue from sales, as of 2005.^[1] However UNIX-based systems, many of which are free, are more popular. FreeBSD is a Unix-like free operating system descended from AT&T UNIX via the Berkeley Software Distribution (BSD) branch through the 386BSD and 4. ... Solaris is a computer operating system developed by Sun Microsystems. ... This article is about operating systems that use the Linux kernel. ... Filiation of Unix and Unix-like systems Unix (officially trademarked as UNIX®, sometimes also written as or ® with small caps) is a computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs including Ken Thompson, Dennis Ritchie and Douglas McIlroy. ... Minicomputer (colloquially, mini) is a largely obsolete term for a class of multi-user computers which make up the middle range of the computing spectrum, in between the largest multi-user systems (traditionally, mainframe computers) and the smallest single-user systems (microcomputers or personal computers). ... Windows Server may refer to: Windows 2000 Server, the release based on Windows 2000 Windows Server 2003, the current release of Windows Server Windows Server Longhorn, the upcoming release of Windows Server Windows Home Server, an upcoming server operating system intended for home use Microsoft Servers, a family of servers... Year 2005 (MMV) was a common year starting on Saturday (link displays full calendar) of the Gregorian calendar. ...

Server-oriented operating systems tend to have certain features in common that make them more suitable for the server environment, such as the absence of a GUI (or an optional GUI); the ability to be reconfigured (in both hardware and software) to at least some extent without stopping the system; advanced backup facilities to permit online backups of critical data at regular and frequent intervals; facilities to enable the movement of data between different volumes or devices in such a way that is transparent to the end user; flexible and advanced networking capabilities; features (such as daemons in UNIX or services in Windows) that make unattended execution of programs more reliable; tight system security, with advanced user, resource, data, and memory protection, and so on. Server-oriented operating systems in many cases can interact with hardware sensors to detect conditions such as overheating, processor and disk failure, and either alert an operator, take remedial action, or both, depending on the configuration. In human-computer interaction, computer transparency is an aspect of user friendliness which prevents the user from worrying about technical details (like installation, updating, downloading or device drivers). ... In Unix and other computer multitasking operating systems, a daemon is a computer program that runs in the background, rather than under the direct control of a user; they are usually instantiated as processes. ...

Because the requirements of servers are, in some cases, almost diametrically opposed to those of desktop computers, it is extremely difficult to design an operating system that handles both environments well; thus, operating systems that are well suited to the desktop may not be ideal for servers and vice versa. Regardless of OS vendor, system configurations that are ideal for servers may be unsatisfactory for desktop use, and configurations that perform well on the desktop may leave much to be desired on servers. As a result many operating systems have both a server and a desktop version released. Nevertheless, the desktop versions of Windows and the Mac OS X (also Unix-based) operating systems are used on a minority of servers, as are some proprietary mainframe operating systems, such as z/OS. The dominant operating systems among servers continues to be UNIX versions and clones. z/OS Welcome Screen seen through a terminal emulator The title of this article begins with a capital letter due to technical limitations. ...

The rise of the microprocessor-based server was facilitated by the development of several versions of Unix to run on the Intel x86 microprocessor architecture. The Microsoft Windows family of operating systems also runs on Intel hardware, and versions beginning with Windows NT have incorporated features making them suitable for use on servers. Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ... x86 or 80x86 is the generic name of a microprocessor architecture first developed and manufactured by Intel. ... A typical vision of a computer architecture as a series of abstraction layers: hardware, firmware, assembler, kernel, operating system and applications (see also Tanenbaum 79). ... Windows redirects here. ... Windows NT (New Technology) is a family of operating systems produced by Microsoft, the first version of which was released in July 1993. ...

Whilst the role of server and desktop operating systems remains distinct, improvements in both hardware performance and reliability and operating system reliability have blurred the distinction between these two classes of system, which at one point remained largely separate in terms of code base, hardware and vendor providers. Today, many desktop and server operating systems share the same code base, and differ chiefly in terms of configuration. Furthermore, the rationalisation of many corporate applications towards web-based and middleware platforms has lessened the demand for specialist application servers. This article is about integration software. ...

Servers on the Internet

Almost the entire structure of the Internet is based upon a client-server model. High level Root name servers, ISP (Internet Service Providers) DNS servers (Domain Name System) and routers direct the traffic on the internet. Many millions of servers are connected to the Internet and run continuously throughout the world. Client/Server is a network application architecture which separates the client (usually the graphical user interface) from the server. ...

Among the many services provided by Internet servers are: the Web; the Domain Name System; electronic mail; file transfer; instant messaging; streaming audio and video, online gaming, and countless others. Virtually every action taken by an ordinary Internet user requires one or more interactions with one or more servers. WWWs historical logo designed by Robert Cailliau The World Wide Web (commonly shortened to the Web) is a system of interlinked, hypertext documents accessed via the Internet. ... The Domain Name System (DNS) associates various sorts of information with so-called domain names; most importantly, it serves as the phone book for the Internet by translating human-readable computer hostnames, e. ... Electronic mail, abbreviated e-mail or email, is a method of composing, sending, and receiving messages over electronic communication systems. ... This article is about the File Transfer Protocol standardised by the IETF. For other file transfer protocols, see File transfer protocol (disambiguation). ... // Instant messaging (IM) is a form of real-time communication between two or more people based on typed text. ... Streaming media is just-in-time delivery of multimedia information. ... Streaming media is just-in-time delivery of multimedia information. ... Online games are computer or video games played on the Internet or over a computer network. ...

There are also technologies that operate on an inter-server level. Inter-server or interserver is a technical term used in network protocol design to intend an extension to the classic client-server model by having parts of a protocol which are only exchanged between the servers. ...

Servers in daily life

Any computer or device serving out applications or services can technically be called a server. In an office or enterprise environment, the network server is easy to identify. A DSL/Cable router is a server as it provides a computer with application services such as assigning an IP address (via Dynamic Host Configuration Protocol, DHCP), and Network Address Translation (NAT) services which is the firewall that protects a computer from the internet. iTunes software is a music server for MP3 players. Shared printers or folders on a computer use it as a server. These instances can cause security problems for home users. Wireless access points, if not properly secured, can also serve out a network connection to those within range who may then be able to access previously shared data. This is why securing wireless networks has become important of late.^[2] Many private servers are around for such online games as Everquest, Everquest II, GunZ: The Duel, World of Warcraft, Counter-strike etc. DSL may refer to: Damn Small Linux Dark and Shattered Lands, a MUD based loosely on Forgotten Realms and Dragonlance books. ... DHCP redirects here. ... DHCP in the context of computing can stand for: Dynamic Host Configuration Protocol - one of the protocols in the TCP/IP networking suite Decentralized Hospital Computer Program of the United States Department of Veterans Affairs This article consisting of a 4-letter acronym or initialism is a disambiguation page — a... In computer networking, Network Address Translation (NAT, also known as Network Masquerading, Native Address Translation or IP Masquerading) is a technique of transceiving network traffic through a router that involves re-writing the source and/or destination IP addresses and usually also the TCP/UDP port numbers of IP packets... Firewall may refer to: Firewall (construction), a physical barrier inside a building or vehicle, designed to limit the spread of fire, heat and structural collapse Firewall (networking), a logical barrier designed to prevent unauthorized or unwanted communications between sections of a computer network Firewall (film), a 2006 action film written... This article is about the iTunes application. ... Planet WAP-4000 Wireless Access Point In computer networking, a wireless access point (WAP or AP) is a device that connects wireless communication devices together to form a wireless network. ... Wireless networks are very common, both for organizations and individuals. ... EverQuest (or colloquially, EQ) is a 3D fantasy-themed massively multiplayer online role-playing game (MMORPG) that was released on March 16, 1999. ... Input methods Keyboard, Mouse EverQuest II (EQ2), based upon the popular EverQuest, is a fantasy massively multiplayer online role-playing game (MMORPG) developed by Sony Online Entertainment (SOE) and shipped on November 8, 2004. ... World of Warcraft (commonly abbreviated as WoW) is a massive multiplayer online role-playing game (MMORPG) developed by Blizzard Entertainment and is the fourth game in the Warcraft series, excluding expansion packs and the cancelled Warcraft Adventures: Lord of the Clans. ... Counter-Strike (CS) is a popular team-based mod of Valves first-person shooter (FPS) Half-Life. ...

References

1. ^ CNET News.com, Windows bumps Unix as top server OS, February, 2006
2. ^ How to Make Your 802.11b Wireless Home Network More Secure

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