Definition - What does Network mean?
A network, in computing, is a group of two or more devices that can communicate. In practice, a network is comprised of a number of different computer systems connected by physical and/or wireless connections. The scale can range from a single PC sharing out basic peripherals to massive data centers located around the World, to the Internet itself. Regardless of scope, all networks allow computers and/or individuals to share information and resources.
Computer networks serve a number of purposes, some of which include:
- Communications such as email, instant messaging, chat rooms, etc.
- Shared hardware such as printers and input devices
- Shared data and information through the use of shared storage devices
- Shared software, which is achieved by running applications on remote computers
Techopedia explains Network
Early computer networks of the late 1950s included the U.S. military’s Semi-Automatic Ground Environment (SAGE) and the commercial airline reservation system called the Semi-Automatic Business Research Environment (SABRE). Based on designs developed in the 1960s, the Advanced Research Projects Agency Network (ARPANET) was created in 1969 by the U.S. Department of Defense and was based on circuit switching – the idea that a single communication line, such as a two-party telephone connection, deserves a dedicated circuit for the duration of the communication. This simple network evolved into the present day Internet.
Some of the basic hardware components that can be used in networks include:
- Interface Cards: These allow computers to communicate over the network with a low-level addressing system using media access control (MAC) addresses to distinguish one computer from another.
- Repeaters: These are electronic devices that amplify communication signals and also filter noise from interfering with the signals.
- Hubs: These contain multiple ports, allowing a packet of information/data to be copied unmodified and sent to all computers on the network.
- Bridges: These connect network segments, which allows information to flow only to specific destinations
- Switches: These are devices that forward, make forwarding decisions and otherwise filter chunks of data communication between ports according to the MAC addresses in the packets of information.
- Routers: These are devices that forward packets between networks by processing the information in the packet.
- Firewalls: These reject network access requests from unsafe sources, but allow requests for safe ones.
There are various types of networks, which are classified according to specific characteristics such as connection types, whether they are wired or wireless, the scale of the network, and its architecture and topology. Network types include local area networks, wide area networks, metropolitan area networks and backbone networks.