Networks
Network
A network is a collection of entities that exchange information
or goods.A few examples of networks are railway system, nervous system of
animals, telephone system.
Computer Network
A network consists of two or more computers that are
linked in order to share resources (such as printers and CD-ROMs),exchange
files, or allow electronic communication.The computers on a network may be
linked through cables, telephone lines, radio waves, satellites, or infrared
light beams.
A communications network is a system of interconnected
computers, and communication devices that can communicate with one another and
share resoureces. At the most elementary level, a computer network consists of
two computers connected with each other by a cable to allow them to share
data.A device connected to a network is called a node.A node may be a device
such as a computer, a printer, workstation etc.
Local Area Network (LAN) -
LANs are networks usually confined to a
geographic area, such as a single building or a college campus. LANs can be
small, linking as few as three computers, but often link hundreds of computers.
Metropolitan Area Network (MAN) –
MAN is basically a bigger version of a LAN and normally uses similar
technology. It might cover a group of near by corporate offices or a city and
might be either private or public.
Wide Area Network (WAN) –
Often a network is located in multiple physical places. Wide area networking combines multiple LANs that are geographically
separate. This is accomplished by connecting the different LANs using services
such as dedicated leased phone lines, dial-up phone lines (both synchronous and
asynchronous), satellite links, and data packet carrier services.