NETWORKS

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LAN: A LAN is a local area network which covers a small geographical area located on a single site. All the hardware for LAN s owned by the organisation that uses it. LANs are either wired or wireless

WAN: A WAN is a wide area network that connects LANs that are in different geographical locations. Unlike a LAN, organisations hire infrastructure from telecommunication companies, who own and manage the WAN. WANS can be connected using fibre or copper telephone lines , satellite links or radio links.

A network is a group of computers connected together to communicate and share resources.

Things that affect the performance of a network:

Bandwidth

Heavy use

Wired/ Wireless

Choice of hardware

NCI's , switches and routers

A Network interface Controller is an internal piece of hardware that allows a device to connect to a network.

Switches connect devices on a LAN.

Routers are responsible for transmitting data between networks

Client server networks are managed by a server. The devices connected to the server are clients. Files and software are stored centrally on the server. The server stores user profiles, passwords and access information.

In peer-peer networks all devices are equal, connecting directly to each other without a server. You store files on individual devices and share them with others.

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Network topologies

A topology is basically the layout of the network.

In a star topology , all devices are connected to a central switch or server that controls the network.

A mesh topology is decentralised . Networking devices are either directly or indirectly connected to every other one without the need for one central switch or server.

Network protocols

A protocol is a set of rules for how devices communicate and how data is transmitted across a network.

Data is set between networks in packets.

Packet switching is used by routers to direct data packets on the internet and other IP networks.

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