Computer networking device

Computer networking devices are units that mediate data in a computer network. Computer networking devices are also called network equipment, Intermediate Systems (IS) or InterWorking Unit (IWU). Units which are the last receiver or generate data are called hosts or data terminal equipment.

 List of computer networking devices

Common basic networking devices:

• Router: a specialized network device that determines the next network point to which it can forward a data packet towards the destination of the packet. Unlike a gateway, it cannot interface different protocols. Works on OSI layer 3.

• Bridge: a device that connects multiple network segments along the data link layer. Works on OSI layer 2.
• Switch: a device that allocates traffic from one network segment to certain lines (intended destination(s)) which connect the segment to another network segment. So unlike a hub a switch splits the network traffic and sends it to different destinations rather than to all systems on the network. Works on OSI layer 2.
• Hub: connects multiple Ethernet segments together making them act as a single segment. When using a hub, every attached all the objects, compared to switches, which provide a dedicated connection between individual nodes. Works on OSI layer 1.
• Repeater: device to amplify or regenerate digital signals received while sending them from one part of a network into another. Works on OSI layer 1.

Some hybrid network devices:

• Multilayer Switch: a switch which, 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 transmissions, such as asynchronous and synchronous transmissions.
• Bridge Router (B router): CombineS router and bridge functionality and are therefore working on OSI layers 2 and 3.

Hardware or software components that typically sit on the connection point of different networks, e.g. between an internal network and an external network:

• Proxy: computer network service 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

• Network Address Translator: network service provide as hardware or software that converts internal to external network addresses and vice versa

Other hardware for establishing networks or dial-up connections:

• Multiplexer: device that combines several electrical signals into a single signal
• Network Card: a piece of computer hardware to allow the attached computer to communicate by network
• Modem: 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, as a computer communicating with another computer over the telephone network
• ISDN terminal adapter (TA): a specialized gateway for ISDN
• Line Driver: a device to increase transmission distance by amplifying the signal. Base-band networks only