Information and Communication Technologies: Networking

1. Wired network connection

2. Copper co-axial cable –

The copper co-axial cables are good conductor of electricity i.e. Em waves and these wires are co-axial because it saves from electric flux losses. The copper co-axial cables are able to support multiple channels within a single wire.

The audio singles are converted into Em waves that are passed through these wires as potential differences.

Disadvantages –

1. Copper is a good conductor of heat therefore it makes losses of signal. Hence it requires repeaters and amplifiers periodically.
2. The number of channels that it supports is very less.
3. Thin wires of copper can’t be made
4. The copper cables require high maintenance

2. optical fibers

Optical fiber consists of 3 layers –

1. fiberglass layer – That has the highest density
2. Cladding – its density is lower than the fiberglass layer
3. Coating – it is only a protective layer & its density may be more or less

 The optical fibers are based on the principle of total internal reflection (TIR) the Em signals are converted into optical signals & then it is passed through the fiberglass layer at an angle which is greater than critical angle so that TIR should take place.

The frequency of light is very large hence it is not possible to copy it. Therefore optical fiber communication is very safe.

Optical use light that travels very fast and communication can take place at the same instant voluminous data can be sent at a very high speed.

Application of optical fibers –

1. In medical optical fibers are used to find out ulcer & oral cancer & also used for bloodless surgery, leis laser surgery, etc.
2. In engineering, optical fibers are used in the construction of large buildings, dams, etc. to find out any hairline strain
3. Optical fibers are used in e-governance such as BMP, NOFN

1. White Fi (Microsoft) –

Microsoft came out with innovative technology in which it reflects Em waves that are idle from one area to another area and this frequency would be used to provide broadband internet connectivity through Wi-Fi in that area.

1^st city under white Fi is Bangalore.

1. Free basics (Facebook) –

Facebook launched the concept of free basics in which the basic requirement such as air water and internet connectivity must be made free and it should be available to all.

1. Wireless network Connections –
2. Bluetooth –

It is a personal area network communication in which a frequency signal of 2.5 GHz is generated. Bluetooth requires very little energy therefore, it can be integrated with very smaller devices also such as speakers, mobile phones.

The Bluetooth tech works by identification of MAC addresses that are the private addresses of all digital devices. The Bluetooth can be generated by integrating a microchip in a device that radiates signals in all directions. The other Bluetooth device in a range of 10 m can identify the signals & can interfere constructively. After this the signals become unidirectional & this is called pairing up of the devices. In pairing mode higher data content such as audio, video, multimedia can be sent.

Note –

The Bluetooth 4.0 discovered in 2016 has a range of up to 400 m.

Bluetooth does ‘not require line of sight communication therefore the Bluetooth signal can pass through the opaque media such as walls, buildings, trees, etc.

2) Wi-Fi (Wireless Fidelity) –

A Wi-Fi is a local area network that has a range of up to 100 m it is created by embedding a microchip in a device that radiates signal in all directions. Its freq. is from 2.5 GHz. ∴ It cannot with multiple devices at the same time without the read of pairing up. Wi-Fi also doesn’t require line of sight communication. 

There are 2 types of Wi-Fi –

1) Provided by a public service provider such as Vodaphone idea, BSNL, etc.

2) Provided by a private network that identifies MAK address.  

The Wi-Fi can be created at a static point or it can be created in a moving vehicle such as bus-train etc. Wi-Fi hotspot. The Wi-Fi signal is of higher freq. hence it can support audio, video, multimedia at the same time. It is used in homes, offices, etc.

Note –

The basic difference between Wi-Fi & Bluetooth is –

1. Range
2. Wi-Fi can cannot with multiple devices
3. Wi-Fi requires more power than Bluetooth.

If you are preparing for GATE and ESE, avail BYJU'S Exam Prep Online Classroom Program to get unlimited access to all the Live Structured Courses and Mock Tests from the following link :

• ESE and GATE ECE Online Classroom Program (24+ Live classes and 150+ mock tests)

• ESE and GATE EE Online Classroom Program (24+ Live classes and 193+ mock tests)

• ESE and GATE CE Online Classroom Program (24+ Live classes and 180+ mock tests)

• ESE and GATE ME Online Classroom Program (24+ Live classes and 161+ mock tests)

Thanks 
Sahi Prep Hai Toh Life Set Hai!