The document provides an overview of topics discussed in a seminar on summer training from BSNL, including: 1) An introduction to BSNL as India's largest telecommunications provider and its history. 2) Overviews of telecommunication networks, broadband access technologies like DSL and cable, 3G communication, and optical fiber communication. 3) Details are given on switching systems, the evolution of electronic switching, broadband definitions and technologies like fiber, cable, wireless, and satellite. 4) Optical fiber communication is described in terms of its construction, modes of propagation, advantages, and applications in telecommunications.

1. Seminar on
SUMMER TRAINING
from
BSNL
BY:- Pankaj Kumar Tiwari

2. CONTENTS
• Introduction to BSNL
• Overview of telecommunication network
• Overview of broadband access technology
• 3-G communication
• Over view of optical fiber communication
• Summary

3. Introduction to BSNL
• BSNL is an Indian state-owned telecommunications
company.
• It was incorporated on 15 September 2000.
• It is India’s largest and oldest communication
service provider.
• Before 2000 ,it was known as Department of
telecommunication (DoT).
• BSNL is at 5th position as an operator with
Market share of 9%.

5. Overview of telecommunication
Network
• The telephone is a telecommunication device that is
used to transmit and receive electronically or
digitally encoded speech between two or more
people.
• Telecommunication network carry information
signals among entities.
• The communication switching system enables the
universal connectivity
• The telecommunication links and switching are
mainly designed for voice communication.
• In telephone system the frequency it passes are
restricted to between 300 to3400Hz.

6. Switching system fundamentals
• Telecommunication switching system generally
perform three basic function.
• They transmit signals over the connection or over
separate channels to convey the identity of the called
address.
• They establish connection through a switching
network for conversational use during the call.
• They process the signal information to control and
supervise the establishment and disconnection of
the switching network connection.

7. • evolution of electronic switching system
Manual
Step by step
1950 1960 1970 1980 1990 2000 2010 2020
Crossbar switch
SPC ,analog switching
SPC, digital switching
Broadband
Broadband (optical)
Year

8. Overview of Broadband technology

9. Introduction
• A concept of broadband services and the means
of access technologies to bridge the customer
and service provider is emerged out through out
the world .
• Broadband refers to high speed internet access.
• The rapid growth of distributed business
application , e-commerce generate the demand
for bandwidth and access network.

10. Definition of Broadband
• Broadband is the nonspecific term for high speed
digital internet access. There are the various ways to
define the broadband.
• Term for evolving digital technologies that provide
customers a high speed data network connection.
• The federal communication commission defines
broadband as an advanced telecommunication
capability.
• Delivers service & facilities with an upstream and
downstream speed range varies from 128Kbps to
100Mbps.

11. Need of Broadband
• Professional activities
• Entertainment activities
• Consumer activities

12. Technology options for Broadband
services
• Communication of data throughput is feasible by
fallowing technologies:-
• Narrow band 2.4 kbps -128kbps
• Broadband 256kbps-8000kbps
• LAN 1000kbps-100Mbps

13. Broadband communication technology
can be divided in to following
• Wireline technology
• A) optical fiber technologies
• B) cable TV network
• Wireless technology
• A) 3G mobile
• B) Wi-Fi
• C) wimax
• D) satellite media

14. 3G communication

15. Introduction
• 3G is the next generation of wireless network
technology that provides high speed bandwidth
to handheld device.
• 3G wireless network support the following
maximum data transfer rates.
• 2.05Mbits/sec to stationary device.
• 384Kbits/sec for slow moving device.
• 128Kbits/sec for fast moving device.

16. Charecterstics
• Always on connectivity. 3G network use IP
connectivity.
• Multimedia service with streaming audio and
video.
• Instant messaging with audio and video clips.
• Fast download of large files.

17. Advantage of 3G
• More bandwidth.
• Security.
• Reliability.
• Fixed and variable data rates.
• Always online device.
• Rich multimedia.

18. Disadvantage
• Costly
• Content provisioning to make service popular.
• More high power requirement.
• Application
• Business application
• Multi media services
• Gaming industry

19. Overview of optical fibre
communication

20. • An optical fibre ( or fiber ) is a glass or plastic
fibre that carries light along it’s length.
• It has two main component layers: Core &
Cladding.
• Light is kept in the “core” of optical fibre.
• Cladding is for the protection of fibre.

21. Optical Fibre Construction
• Core: Thin Glass Center of
the fibre where light travels.
• Cladding: Outer Optical
Material surrounding the
Core.
• Buffer Coating: Plastic
Coating that protects the
Fibre.

22. Material Used
• The “Core” , & the lower refractive index
“Cladding” , are typically made of high quality
silica glass, though they can be both made of
plastic as well.

23. Fiber Optic Layers.
• Consists of three concentric sections.
Plastic jacket
Glass or plastic
cladding Fibre core

24. Mode Of Propagation
Two main categories that are used in Fibre
Optic Communications are:
• Single mode Optical Fibre
• Multi- Mode Optical Fibre

25. Single Mode Fibres
• Single-mode fibers – used to transmit one signal per
fiber (used in telephone and cable TV). They have
small cores(9 microns in diameter) and transmit
infra-red light from laser.

26. Multi-mode Fibres
• Multi-mode fibers – used to transmit many
signals per fiber (used in computer networks).
They have larger cores(62.5 microns in
diameter) and transmit infra-red light from
LED.

27. Fibre Optic Cable
• Single-mode Fibre:
Carries light pulses
along single path.
• Multi-mode Fibre:
Many pulses of light
Generated by LED
At different angles.

28. Fiber Optic Communication
• It is a method of transmitting information from
one place to another by sending light through an
optical fiber.
• The light forms an electromagnetic carrier wave
that is modulated to carry information.

29. Block Diagram of OFC

30. Advantages of Optical fibre
• Thinner than other tubes.
• Less expensive
• High Carrying Capacity.
• Provides a very large Bandwidth
• Less signal distortion
• Non- flammable
• Light Weight

31. Fibre Optic Disadvantages
• Expensive over short distance.
• Very high Installation charges
& demands high skills.
• Adding additional nodes is
difficult.

32. Areas Of Application
• Telecommunication
• Local Area Networks
• Cable TV
• CCTV
• Optical Fibre Sensors

33. Summary
• So we can say that our daily routine is dependent
on the communication technique like that 3G,
Broad band & optical fibre etc.