“Data communication means sharing the information. This sharing can be local or remote or with in a building. Local communication usually occurs in face to face, while remote communication takes place over distance.”
Data communication is the exchange of data between the two devices via some of transmission medium. Data communication devices must be the part of the communication system made up of combination of hardware and software.
Components of data communication: The following are the five major components of data communication system.
Message: the information which is to be communicated.
Sender: it can be computer, workstation, telephone, etc.
Receiver: it can be computer, workstation, telephone, etc.
Medium: it is physical path by which the message travels from sender to receiver.
Protocol: it is the set of rules that govern the data communication.
Signals used in communication: different types of signals used in communication are analog and digital.
Analog signal: Analog refers to continues set of specific points of data and all possible points between. Analog signals can have any value in a range.
Local area Network (LAN): when two or more computers are connected in a small are i.e. within a diameter of not more than a few kilometers then such network is known as local area network. It is made for an organization and most of the times it is within a single building. The data rate in LAN is in the form of Mbps. The characteristics of LAN are:
it covers an area of less than 5 kilometers
it provides high speed data communication
They have low error rates.
They use simple data communication protocols.
Wide area network (WAN): a wide area network is connection of two or more computers which are geographically dispersed. It has longer distance communications than LAN. It uses public networks like telephone network or microwave relays for communication facilities. A cost is involved with such networks so high mostly it is used by government agencies.
The characteristics of WAN are:
It inter connects computers at different sites.
it can connect two or more LAN’s too
It operates nationwide or worldwide.
Links are slow as compared to LAN’s i.e. 1200 kbps
Metropolitan area Network (MAN): it resides between LAN and WAN. It interconnects computer within a city. It uses dual queue dual bus protocol. The implementation for MAN provides transfer rates from 34 mbps which is not very slow as compared to LAN. They use broad band cables as transmission media. They also use fibre optical cable as transmission media.
Difference Between LAN MAN WAN
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