This document provides a summary of Bharat Sanchar Nigam Limited (BSNL), India's state-owned telecommunications company. It discusses that BSNL is the world's seventh largest telecom company and its responsibilities include improving existing telecom services, expanding rural services, and building customer confidence. It offers various telecom services across India such as wireless, mobile, internet, broadband, and voice over IP. The document also provides an overview of BSNL's telecommunication network including telephone exchanges, main distribution frames, and switch rooms.

1. Industrial Training Seminar on
BSNL
Submitted By:-
PRADEEP YADAV
B.Tech.(EC)
Final Year
Roll No. 111300129
SESSION : 2014-15

2. Bharat Sanchar Nigam Limited is the world’s seventh largest
telecommunication company.
Its responsibilities includes improvement of the quality of
already installed telecom services, expansion of telecom
services in rural areas and acquiring confidence among its
customers.
It provides a comprehensive range of services in India,
which include wireless connections, CDMA mobile, GSM
lines, Internet, broadband, MPLS-VPN (multi protocol label
switching-virtual private network), VSAT (very small
aperture terminal) WIMAX,FTTHand VOIP (voice over
Internet protocol).
Within this short span of time, it has also become one of the
largest public sector companies in India.
INTRODUCTION

3. This section includes brief introduction of how a call is processed when we
dial a call from basic telephone to another basic telephone or from basic to
mobile or vice versa.
CALL SETUP:
When a subscriber calls to another subscriber first its request goes to the
nearest switching centre that is PSTN (Public Switching Telecommunication
Network). Then it processes the caller and subscriber’s number if it exists in
the same BSC (Base Station Controller) then call setup is completed.
If subscriber is not in the same BSC then call transfer to MSC (Mobile
Switching Centre) then it transfers the call to prior BSC then call setup is
completed.
If Caller calls to a mobile subscriber then call transfer is done by MTSO(Mobile
Telephone Switching Office)
now call transfer is done on BTS (Base Transceiver Station) and call setup is
completed.
WORKING OF BASIC TELECOMMUNICATION NETWORK

5. Parts of a Telecommunication network
The main parts of a Telecommunication network are:
1.Telephone Exchange
2.Main Distribution Frame (MDF)
3.Switch Room

6. TELEPHONE EXCHANGE
Equipment which effects
interconnection of telephones is
known as switching equipment.
The switching centre, which houses
the terminating and switching
equipment is called telephone
exchange.
A telephone exchange is a
telecommunication system used in
the public switched telephone
network or in large enterprises. An
exchange consists of electronic
components that interconnect
(switch) telephone subscriber lines
or virtual circuits of digital systems
to establish telephone calls between
subscribers

7. All telephone subscribers are served by automatic
exchanges.
Today’s automatic exchanges use a pair of computers.
One running the program that provides services.
Second, monitoring the operation of the first, ready to
take over in a few seconds in the event of equipment
failure.
Various exchanges present in BSNL are:
1. C-DOT
2. OCB(ORGANE DE COMMANDE B2 VERSION)
3. EWSD
About the exchange

8. C-DOT
It work on telecom technology, products and services.
Provide solutions for current and future requirements of
telecommunication and converged networks including those
required for rural application.
Provide market orientation to R & D activities and sustain C-DOT as
center of excellence.
OCB(ORGANE DE COMMANDE B2 VERSION)
It is a digital switching system.
The system supports all the existing signaling system.
The system has ‘auto recovery’ feature. When a serious fault occur
in control unit, it gives a message to SMM (operation &
maintenance unit).

9. OCB(ORGANE DE COMMANDE B2 VERSION)

10. EWSD
The EWSD Digital Switching Systems offer a
wide range of telephony features and
supplementary services. Further capabilities
can be developed to meet specific customer
needs.

11. MAIN DISTRIBUTION FRAME(MDF)
M.D.F. is a media between switching network and subscriber’s line. It is a termination point
within the local telephone exchange where exchange equipment and terminations of local
loops are connected by jumper wires.
FUNCTIONS OF MDF:
All cable copper wires supplying services through user telephone lines are terminated and
distributed through MDF.
The most common kind of large MDF is a long steel rack accessible from both sides. Each
jumper is a twisted wire.
It consists of local connection and broadband connection frames for the main Exchange
area.
The MDF usually holds central office protective devices including heat coils and functions
as a test point between a line and the office.
It provides testing of calls.
It checks whether fault is indoor or external.
All lines terminate individually

12. Structure Of MDF

13. ORGANIZATION OF MDF
• Vertical side
• Horizontal side
Vertical side
Rack:- On the rack, the tags are situated. One rack is having eight tags.
The counting is done from up (0) to down (7).
Tags:- Each rack consists of eight tags
1 tag = 4 core
1 core = 4 bunch
1 bunch = 2 line
N.E:-The word NE stands for the ‘NUMBER OF EQUIPMENT’. It is used
for testing number.
Wedge:- Wedge is used as a device for checking the ring. Wedge is
placed in jack strips, which is connected to telephone for checking.

14. Horizontal side
The horizontal side connected to the
underground cable.
This cable is having 100 pairs. These pair are
distributed when company allot the telephone
number to the subscriber.
Horizontal side is again subdivided in
two parts:
One part is connected with the vertical
side.
Another with the subscriber line by using
100 pair underground cable.

15. POWER PLANT
As we know that, the power is the main source or any
organization. It is the case of E-10B exchange. That is the
first requirement of any organization is the input.
The main source of this exchange is AC supply.
The main part of power room are:-
1. Batteries for providing 48V supply
2. UPS (Uninterruptable Power Supply)
3. Charging - Discharging Unit
4. Inverter and Converter Unit

16. Switch Room
Switch room consists of
BM(Benjamin Moore) and
CM cabinets mounted in
standard switch.
These cabinets are
fastened to a switch Room
and interconnected by
cables

17. VARIOUS INTERNET SERVICES
LEASED LINES
The information sent through the leased line travels along dedicated secure channels, eliminating the
congestion that occurs in shared networks.
between two points set up by a telecommunications carrier. They can be used for telephone, data, or
Internet services
A leased line (dedicated line) is a permanent Optical Fibre Cable(OFC) or telephone connection.
It is commonly used in ATMs.
WI-FI (WIRELESS FIDELITY)
A Wi-Fi network provides the features and benefits of traditional LAN technologies such as Ethernet and
Token Ring without the limitations of wires or cables.
WIFI is a wireless LAN Technology to deliver wireless broad band speeds up to 54 Mbps to Laptops, PCs
Wi-Fi enabled phones etc.

18. GENERAL PACKET RADIO SERVICE (GPRS)
General packet radio service (GPRS) is a packet oriented mobile data service available to users of
the 2G cellular communication systems, global system for mobile communications (GSM), as well
as in the 3G systems. In 2G systems, GPRS provides data rates of 56-114 kbps
GPRS extends the GSM circuit switched data capabilities and makes the following services
possible:
1. “ Always on” Internet access.
2.Multimedia messaging service (MMS).
3.Push to talk over cellular (PoC/PTT).
4.Point to Point (P2P) service: inter-networking with the internet (IP).
5.Increase message sending speed 30 messages per minute approximately.

19. BSNL Broadband Service
Broadband refers to a connection that has capacity to transmit large amount of data at
high speed. Presently a connection having download speeds of 256 kbps or more is
classified as broadband. When connected to the Internet broadband connection allows
surfing or downloading much faster than a dial-up or any other narrowband
connections. BSNL offers 2 Mbps minimum download speed for its Broadband
connections.
Requirement for providing Broad Band connection
1.Personal Computer
2.ADSL(Asymmetric Digital Subscriber Line) Modem.
3.Land Line Connection
4.Splitter for separating telephone from Personal computer
5.High speed Internet Access: This is the always-on Internet access service with speed
ranging from 256 kbps to 8 Mbps.

20. WIMAX
WI-MAX is an acronym that stands for World-wide Interoperability for Microwave
Access and this technology is designed to accommodate both fixed and mobile
broadband applications.
SALIENT FEATURES OF WIMAX ARE:
1.OFDM-based physical layer.
2.Very high peak data rates.
3.Adaptive modulation and coding (AMC)
4.Support for TDD and FDD OFDMA.
5.Flexible and dynamic per user resource allocation.
6.Support for mobility.
7.IP-based architecture.
FTTH
FTTH is an acronym which stands for Fiber To The Home.In this technology an optical
fiber of high bandwidth and frequency is connected to the local residence of the user to
provide high speed internet facility upto higher mbps to gbps.This facility is first
launched by BSNL in India.

21. IPv4(Internet Protocol version 4) Addressing
This section covers some of the basic concepts of IPv4 addressing, such as how the Internet's
address architecture uses the binary and dotted-decimal versions of IPv4 addressing. This section
also reviews the structure of IPv4 addresses, such as the various classes of IPv4 . 32-bit IP
addresses are written using dotted-decimal notation. Each 32-bit address is divided into four
groups of eight, called octets. Each octet is converted to decimal and then separated by decimal
points, or dots.Bit IP addresses are written using dotted-decimal notation.
A 32-bit IP address is a binary number:
10101100000111101000000000010001
This binary number can be divided into four octets:
10101100 00011110 10000000 00010001
Each octet (or byte) can be converted to decimal:
172 30 128 17
Finally, the address can be written in dotted-decimal notation:
172.30.128.17

22. Various classes of IPV4 address

23. FIBER OPTICS TRANSMISSION SYSTEM
FIBER OPTICS: The use and demand for optical fiber has grown tremendously and
optical-fiber applications are numerous. Telecommunication applications are
widespread, ranging from global networks to desktop computers. These involve the
transmission of voice, data, or video over distances of less than a meter to hundreds of
kilometers, using one of a few standard fiber designs in one of several cable designs.
ADVANTAGES OF FIBRE OPTICS :
Fiber Optics has the following advantages :
• SPEED: Fiber optic networks operate at high speeds - up into the gigabits
• BANDWIDTH: large carrying capacity
• DISTANCE: Signals can be transmitted further without needing to be "refreshed" or
strengthened.
• RESISTANCE: Greater resistance to electromagnetic noise such as radios, motors or
other nearby cables.
• MAINTENANCE: Fiber optic cables costs much less to maintain.

24. OPTICAL FIBER CABLE(OFC)
Optical Fiber is new medium, in which information (voice, Data or Video) is
transmitted on the principle of Total Internal Reflection through a glass or plastic fiber,
in the form of light.
In the following sequence.
1.Information is encoded into Electrical Signals.
2.Electrical Signals are converted into light Signals.
3.Light Travels down the Fiber.
4.A Detector Changes the Light Signals into Electrical Signals.
5.Electrical Signals are decoded into Information.

25. In wireless communication every region is divided into cells.
Cell size is constant for whole system. GSM is a form of
multiplexing, which divides the available bandwidth among
the different channels. Most of the times the multiplexing
used is either TDM (Time division multiplexing) or FDM
(Frequency Division Multiplexing). SM differs from its
predecessor technologies in that both signaling and speech
channels are digital, and thus GSM is considered a second
generation (2G) mobile phone system.

26. • 2G GSM networks operate in the 900 MHz or
1800 MHz bands
• GSM-900 uses 890–915 MHz to send information
from the mobile station to the base station (uplink)
• 935–960 MHz for the other direction (downlink),
• providing 125 RF channels (channel numbers 0
to 124) spaced at 200 kHz. Duplex spacing of 45
MHz is used.

27. CODE DIVISION MULTIPLE ACCESS (CDMA)
Code Division Multiple Access (CDMA) consistently provides better capacity
for voice and data communications that other commercial mobile technologies,
allowing more subscribers to connect at any given time, and it is the common
platform on which 3G technologies are built.
CDMA is a spread spectrum technology, allowing many users to occupy the
same time and frequency allocations in a given band/space
ADVANTAGES OF CDMA:
Increased cellular communications security
Simultaneous conversations
Low power requirements and little cell-to-cell coordination needed by
operators.
Extended reach-beneficial to rural users situated far from cells.

29. • MS refers to the physical
phone itself uniquely
identified by the International
Mobile Equipment Identity
(IMEI) number.
• SIM(Subsciber Identification
Module) is small smart card
that is inserted into the phone
and carries information
specific to the subscriber
identified by International
Mobile Subscriber Identity
(IMSI) number.

30. • It carry out radio communications
between the network and the MS.
• It has handles speech encoding,
encryption, multiplexing (TDMA), and
responsible for modulation and
demodulation.
•Installed between 1 and 16 Transceivers
(TRX)

31. • It is responsible for allocation of radio
channels.
•Operates frequency administration
•power and signal measurements from the
Mobile station.
•handovers from one BTS to another.

32. •It is responsible for call routing, call
setup, and basic switching functions.
•Different BSCs are connected to the MSC.
• Inner-BSC handoffs as well as
coordinates with other MSC's for inter-
MSC handoffs.

33. DATABASES
 HLR(Home Location Register ) maintains
subscriber specific information such as the
MS,ISDN(Integrated Services Digital
Network), IMSI, current location
of the MS, roaming restrictions.
 VLR(Visitor Location Register ) is a database
that contains a subset of the information
located on the HLR.

34. REFERENCES
1. Data Communication And Networking- Behrouz A. Foruzan
2. Wireless Communication and Networks-William Stallings
3. Computer Networking – Kurose & Ross
4. www.bsnl.co.in
5. www.newbsnl.co.in