Computer network is a form of electronic communication. The network might either be a small or a large number of computers which are linked at different places. The network may be divided in two categories which is based on the operational area of the network.
- Local Area Network (LAN)
- Wide Area Network (WAN)
Local Area Network (LAN):
A Local Area Network is a small group of computers (generally about 3 to 50 terminals) interconnected together and located inside a single building of same organization or institution, or within a limited area. All the terminals are connected with a main computer which is widely known as server. LAN supports a range of about 10km. Computer terminals (workstations) are attached to the server (main computer). The server stores all sorts of data, programs, files, and different software, and provides them to the workstations. LAN system can have more than one server. A device called Network Interface Unit (NIU) establishes the link between networks. All these are connected through cables which are similar to Cable Television connection
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Features of LAN:
Main users of LAN are as follows
- Multiuser– It allows many users to share the server at one time and have direct access to hardware and software. Any user can get the printout from a printer by using certain set of commands.
- Communication – The nodes (terminal) can be used for transferring the messages i.e. the nodes can perform a function similar to that of an intercom.
- Security – The LAN system does not provide foolproof security system. However, it has in-built security features and access to the users can also be controlled.
- Mobility – The terminals can be changed and placed at desired locations. Addition and removal of terminals is very simple.
Drawbacks:
The system has a major drawback in that entire functioning is dependent on a server. Thus, any fault or breakdown in the server affects the complete functioning. It means that the nodes connected to it will not function.
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