Introduction to computer IT-101

Lecture #5

Communication, Telecommunication

Communication

• The exchanging of information, ideas or newsis called Communication.

• Two way process of reaching mutualunderstanding in which participants not onlyexchange information but also create andshare meanings.

Telecommunication

• Communication over a distance by cable,telegraph, telephone, or broadcasting is calledtelecommunication.

• Telecommunication is the process oftransferring data electronically from one placeto another. Data can be transferred usingdifferent medium.

• Basic elements of data communication are:

1. Sender

2. Medium

3. Receiver

Sender

• The sender is the device that sends the data. It is also called Source.

Example:

• Computer, mobile device etc

Medium

• The medium is the physical path that connects the sender and the receiver. It is used to transmit data. It is also called communication channel.

Example:

• Copper wire, Fiber-optic cable, air waves etc.

Receiver

• The receiver is the device that accept the data. It is also called sink.

Example:

• Computer, Printer etc.

Method of transferring Message

Computer Networks

• Computer network connects two or moreautonomous computers.

• The computers can be geographically locatedanywhere.

PAN,LAN, MAN & WAN

PAN(Personal Area Network)

• A computer network organized around anindividual person. Personal area networkstypically involve a mobile computer, a cellphone and/or a handheld computing devicesuch as a PDA.

PAN,LAN, MAN & WAN

LAN(Local Area Network):• Network in small geographical Area (Room,

Building or a Campus) is called LAN (LocalArea Network)

• A network of computers located in the samebuilding or different nearby buildings

• Example:

– Computer network of a University campus

PAN,LAN, MAN & WAN

MAN (Metropolitan Area Network)• Network in a City is call MAN (Metropolitan

Area Network) that is connect the LAN withinthe city.

PAN,LAN, MAN & WAN

WAN(Wide Area Network)

• A network in which computers are separated by great distances, typically across cities or even continents

• May consist of several interconnected LANs

Example: The network connecting the ATM of a bank

located in various cities

Internet