Networking hardware, also known as network equipment or computer networking devices, are electronic devices that are required for communication and interaction between devices on a

computer network A computer network is a collection of communicating computers and other devices, such as printers and smart phones. In order to communicate, the computers and devices must be connected by wired media like copper cables, optical fibers, or b ...

. Specifically, they mediate

data transmission Data communication, including data transmission and data reception, is the transfer of data, signal transmission, transmitted and received over a Point-to-point (telecommunications), point-to-point or point-to-multipoint communication chann ...

in a computer network.IEEE 802.3-2012 Clause 9.1 Units which are the last receiver or generate data are called hosts,

end system In networking jargon, a computer, phone, or internet of things device connected to a computer network is sometimes referred to as an end system or end station, because it sits at the edge of the network. The end user directly interacts with an ...

s or

data terminal equipment Data terminal equipment (DTE) is an end instrument that converts user information into signals or reconverts received signals. It is also called data processing terminal equipment or tail circuit. A DTE device communicates with the data cir ...

Range

Networking devices include a broad range of equipment classified as core network components that interconnect other network components, hybrid components that can be found in the core or border of a network, and hardware or software components that typically sit on the connection point of different networks. One of the most common types of networking hardware today is a copper-based Ethernet adapter, which is a standard inclusion on most modern computer systems.

Wireless networking A wireless network is a computer network that uses wireless data connections between network nodes. Wireless networking allows homes, telecommunications networks, and business installations to avoid the costly process of introducing cables in ...

has become increasingly popular, especially for portable and handheld devices. Other networking hardware used in computers includes

data center A data center is a building, a dedicated space within a building, or a group of buildings used to house computer systems and associated components, such as telecommunications and storage systems. Since IT operations are crucial for busines ...

equipment (such as

file server In computing, a file server (or fileserver) is a computer attached to a network that provides a location for shared disk access, i.e. storage of computer files (such as text, image, sound, video) that can be accessed by workstations within a co ...

database server A database server is a server which uses a database application that provides database services to other computer programs or to computers, as defined by the client–server model. Database management systems (DBMSs) frequently provide database- ...

s and storage areas),

network service In computer networking, a network service is an application running at the network layer and above, that provides data storage, manipulation, presentation, communication or other capability which is often implemented using a client–server or pe ...

s (such as DNS, DHCP,

email Electronic mail (usually shortened to email; alternatively hyphenated e-mail) is a method of transmitting and receiving Digital media, digital messages using electronics, electronic devices over a computer network. It was conceived in the ...

, etc.) as well as devices which assure content delivery. Taking a wider view,

mobile phone A mobile phone or cell phone is a portable telephone that allows users to make and receive calls over a radio frequency link while moving within a designated telephone service area, unlike fixed-location phones ( landline phones). This rad ...

tablet computer A tablet computer, commonly shortened to tablet, is a mobile device, typically with a mobile operating system and touchscreen display processing circuitry, and a rechargeable battery in a single, thin and flat package. Tablets, being computers ...

s and devices associated with the

internet of things Internet of things (IoT) describes devices with sensors, processing ability, software and other technologies that connect and exchange data with other devices and systems over the Internet or other communication networks. The IoT encompasse ...

may also be considered networking hardware. As technology advances and IP-based networks are integrated into building infrastructure and household utilities, network hardware will become an ambiguous term owing to the vastly increasing number of network-capable endpoints.

Specific devices

Network hardware can be classified by its location and role in the network.

Core

Core network components interconnect other network components. * Gateway: an interface providing compatibility between networks by converting transmission speeds, protocols, codes, or security measures. * Router: a networking device that forwards data packets between computer networks. Routers perform the ''traffic directing'' functions on the

Internet The Internet (or internet) is the Global network, global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a internetworking, network of networks ...

. A data packet is typically forwarded from one router to another through the networks that constitute the internetwork until it reaches its destination node. It works on OSI layer 3. *

Switch In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type o ...

: a multi-port device that connects devices together at the same or different speeds on a computer network, by using

packet switching In telecommunications, packet switching is a method of grouping Data (computing), data into short messages in fixed format, i.e. ''network packet, packets,'' that are transmitted over a digital Telecommunications network, network. Packets consi ...

to receive, process and forward data to the destination device. Unlike less advanced network hubs, a network switch forwards data only to one or multiple devices that need to receive it, rather than broadcasting the same data out of each of its ports. It works on OSI layer 2. *

Bridge A bridge is a structure built to Span (engineering), span a physical obstacle (such as a body of water, valley, road, or railway) without blocking the path underneath. It is constructed for the purpose of providing passage over the obstacle, whi ...

: a device that connects multiple

network segment A network segment is a portion of a computer network. The nature and extent of a segment depends on the nature of the network and the device or devices used to interconnect end stations. Ethernet According to the defining IEEE 802.3 standards ...

s. It works on OSI layers 1 and 2. *

Repeater In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Some ...

: an electronic device that receives a

signal A signal is both the process and the result of transmission of data over some media accomplished by embedding some variation. Signals are important in multiple subject fields including signal processing, information theory and biology. In ...

and retransmits it at a higher level or higher power, or onto the other side of an obstruction, so that the signal can cover longer distances. * Repeater hub: for connecting multiple

Ethernet Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...

devices together at the same speed, making them act as a single network segment. It has multiple

input/output In computing, input/output (I/O, i/o, or informally io or IO) is the communication between an information processing system, such as a computer, and the outside world, such as another computer system, peripherals, or a human operator. Inputs a ...

(I/O) ports, in which a

introduced at the input of any

port A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Hamburg, Manch ...

appears at the output of every port except the original incoming. A hub works at the

physical layer In the seven-layer OSI model of computer networking, the physical layer or layer 1 is the first and lowest layer: the layer most closely associated with the physical connection between devices. The physical layer provides an electrical, mechani ...

(layer 1) of the

OSI model The Open Systems Interconnection (OSI) model is a reference model developed by the International Organization for Standardization (ISO) that "provides a common basis for the coordination of standards development for the purpose of systems inter ...

and all devices form a single collision domain. Repeater hubs also participate in collision detection, forwarding a jam signal to all ports if they detect a

collision In physics, a collision is any event in which two or more bodies exert forces on each other in a relatively short time. Although the most common use of the word ''collision'' refers to incidents in which two or more objects collide with great for ...

. Hubs are now largely obsolete, having been replaced by

network switch A network switch (also called switching hub, bridging hub, Ethernet switch, and, by the IEEE, MAC bridge) is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destinat ...

es except in very old installations or specialized applications. *

Wireless access point In Computer networking device, computer networking, a wireless access point (WAP) (also just access point (AP)) is a networking hardware device that allows other Wi-Fi devices to connect to a wired network or wireless network. As a standalone ...

Structured cabling In telecommunications, structured cabling is building or campus cabling infrastructure that consists of a number of standardized smaller elements (hence structured) called subsystems. Structured cabling components include twisted pair and opt ...

Hybrid

Hybrid components can be found in the core or border of a network. * Multilayer switch: a

switch In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type o ...

that, in addition to switching on OSI layer 2, provides functionality at higher protocol layers. * Protocol converter: a hardware device that converts between two different types of transmission, for interoperation. * Bridge router (brouter): a device that works as a bridge and as a router. The brouter routes packets for known protocols and simply forwards all other packets as a bridge would.

Border

Hardware or software components that typically sit on the connection point of different networks (for example, between an internal network and an external network) include: * Proxy server: computer

which allows clients to make indirect network connections to other network services. * Firewall: a piece of hardware or software put on the network to prevent some communications forbidden by the network policy. A firewall typically establishes a barrier between a trusted, secure internal network and another outside network, such as the Internet, that is assumed to not be secure or trusted. * Network address translator (NAT): network service (provided as hardware or as software) that converts internal to external network addresses and vice versa. *

Residential gateway A residential gateway is a small consumer-grade gateway which bridges network access between connected local area network (LAN) hosts to a wide area network (WAN) (such as the Internet) via a modem, or directly connects to a WAN (as in EttH), ...

: interface between a WAN connection to an

Internet service provider An Internet service provider (ISP) is an organization that provides a myriad of services related to accessing, using, managing, or participating in the Internet. ISPs can be organized in various forms, such as commercial, community-owned, no ...

and the

home network Home Network is a Television in Canada, Canadian English-language Discretionary service, discretionary cable television, cable and satellite television, satellite specialty channel owned by Corus Entertainment. Home Network broadcasts programs r ...

. * Terminal server: connects devices with a serial port to a local area network.

End stations

Other hardware devices used for establishing networks or dial-up connections include: *

Network interface controller A network interface controller (NIC, also known as a network interface card, network adapter, LAN adapter and physical network interface) is a computer hardware component that connects a computer to a computer network. Early network interface ...

(NIC): a device connecting a computer to a computer network. *

Wireless network interface controller Wireless communication (or just wireless, when the context allows) is the transfer of information (''telecommunication'') between two or more points without the use of an electrical conductor, optical fiber or other continuous guided med ...

: a device connecting the attached computer to a radio-based computer network. *

Modem The Democratic Movement (, ; MoDem ) is a centre to centre-right political party in France, whose main ideological trends are liberalism and Christian democracy, and that is characterised by a strong pro-Europeanist stance. MoDem was establis ...

: device that modulates an analog "carrier" signal (such as sound) to encode digital information, and that also demodulates such a carrier signal to decode the transmitted information. Used (for example) when a computer communicates with another computer over a telephone network. *

ISDN terminal adapter A terminal adapter or TA is a device that connects a terminal device – a computer, a mobile communications device, or other – to a communications network. ISDN In ISDN terminology, the ''terminal adapter'' connects a ''terminal'' (computer) t ...

(TA): a specialized gateway for ISDN. * Line driver: a device to increase transmission distance by amplifying the signal; used in base-band networks only.

References

External links

USF Explanation of network hardware
{{Electronic systems Computer networking