Class-10 Unit 1.1 Networking and Telecommunication

 Unit 1.1  Networking and Telecommunication

1.Introduction Technology Fundamentals

(1.1) Networking & Telecommunications

(1.2) Ethical and Social Issues in ICT

(1.3) Computer Security

(1.4) E-Commerce

(1.5) Contemporary Technology

FULL FORMS

TECHNICAL TERMS

1. Introduction Technology Fundamentals

 Communication

Communication is the process of sharing information between two or more people. It can happen through talking, writing, or using other methods like gestures or technology.

Telecommunication

The transmission of data and information from one place to another for the purpose of communication is known as telecommunication. E.g. mobile phone, Internet phone, television, landline, radio, etc.

Data communication

Data communication is the process of transferring data and information between computers and other electronic devices. E.g. E-Mail, Chat and phone calls

Components of Data Communication

The five basic components (data, sender, medium, receiver and protocol) are required to make data communication.
         Data (message) : Data is to be communicated between sender and receiver.
         Sender : Sender is a device used to transfer data.

         Medium: Medium is a channel through which sender and receiver make communication.                                                                                                                                                                                      Receiver: Receiver is a device used to receive data.

         Protocol: Protocol is a set of rules followed by sender and receiver.

Data Transmission Mode
Data transmission mode is the way of transmission of data from one location to another. There are three types of transmission mode:
i)  Simplex mode
ii)  Half duplex mode

iii)  Full Duplex Mode

 Simplex mode

Simplex mode is the transmission of data and information that takes place in only one direction. It is a unidirectional mode of data transmission.  Radio, newspaper, television broadcasting, books etc. are examples of simplex mode.

Half duplex mode

Half-duplex is the transmission of data and information that flows in both directions but only one direction at a time. Walky-talky and wireless handset are examples of half-duplex mode.

 

Full duplex mode

Full duplex mode is the transmission of data and information that flows in both direction simultaneously on the transmission path. Mobile and landline phones are examples of full duplex mode.

Communication Media / Transmission Media
A channel or path through which data and information are transmitted between connected devices in a network environment is called communication media.
The two main types of communication media are:
1.  Guided (Wired/bounded) communication media

2.  Unguided (Wireless/unbounded) communication media

1.  Guided (Wired/bounded) Communication Media

The media which uses cable or wire to transfer data and information among computers are called guided communication media. This is an easy, fast and secure way to transfer data and information from one computer to another.

The three types of wire or cable are:

a.  Twisted pair Wire
b.  Co-Axial Cable

c.  Fiber Optic Cable

Twisted Pair Wire

Twisted pair wire is made of copper and a pair of wires are twisted together and insulated with plastic. This is also widely used in landline telephone.

RJ-45 connector is the most popular connector used in twisted-pair wire.

Wires are twisted with each other so as to reduce crosstalk (A disturbance caused by electromagnetic interference, along a circuit or a cable pair).

 The two types of twisted pair wire are:

i.  UTP (Unshielded Twisted Pair)

ii.  STP (Shielded Twisted Pair)

Unshielded twisted pair (UTP)

Unshielded twisted pair is a popular type of cable that consists of two unshielded wires twisted around each other which are used in telephone wiring and local area networks (LANs).

• It is called unshielded because it has no additional foil wrap, or shield. 
• RJ-45 connector is commonly used with unshielded twisted pair.

 

Shielded twisted pair (STP)

Shielded twisted pair is a type of copper telephone wiring in which each of the two copper wires are twisted together and coated with an insulating coating.

The extra covering in shielded twisted pair wiring protects the transmission line from electromagnetic interference. D-shell connectors are used with shielded twisted pair.

Co-axial cable

Coaxial (or “coax”) cable is a common type of cable used for transmitting data over long distances. They are most commonly used to transmit cable TV and Internet signals. BNC and T connectors are the most popular connector used in co-axial cable.
 

Fiber optic cable
Fiber optics cable is one of the costlier cables used in data communication which uses light to carry a data signal through the cable. The connectors used in fiber optics are Screw Mounted Adaptors (SMA), Spring-loaded Twist (ST), SC and FC.

1.  Unguided (Wireless/unbounded) Communication Media
Unguided communication is a communication channel in which data and information transferred between two devices without using wire or cable. It uses radio signal for receiving and transmitting electronic data.
The Some wireless communication are:
Microwave transmission

Microwave is a line-of-sight wireless communication technology that uses high frequency beams of radio waves to provide high speed wireless connections that can send and receive voice, video, and data information.Microwaves do not pass through buildings. So, indoor receivers cannot be used effectively.

• It provides higher bandwidth for data communication. 
• It requires line of sight for data transmission.

 

Infrared transmission

Infrared Transmission is the transmission of data or voice information over infrared (IR) light over short ranges. It requires line-of-sight and is unable to break through walls.

 
Satellite Communication
Satellite communication is used to transfer information wirelessly worldwide after 1965.It is an artificial satellite placed in outer space for the purpose of telecommunication, radio, television, Internet, etc. Text, photo, video, etc. can be transferred worldwide using satellite communication.It is like microwave relay stations in the space or sky.