The document summarizes information about a summer training held at Bharat Sanchar Nigam Limited (BSNL). It discusses BSNL and the services it provides like universal telecom services, cellular services, internet, IPTV, and more. It also provides an overview of key telecommunication topics like telephone exchanges, the network internet backbone, broadband technology, optical fiber, GSM architecture and operations. The training covered technologies powering the telecom industry in India.

1. SUMMER TRAINING
HELD AT BSNL
Aditya Dandotia
091156

2. INTRODUCTION:
•Bharat Sanchar Nigam Limited (abbreviated BSNL)is an
Indian state owned telecommunications company
headquartered in New Delhi. It is the largest provider
of fixed telephony and fourth largest mobile
telephony provider in India, and is also a provider
of broadband services.
•Technological developments in the field of
telecommunication in India have been taking place at much
faster as per the global trend. Particularly during last three
years.
•There has been a major transformation in the switching
technology.

3. SERVICES
 Universal Telecom Services
 Cellular Mobile Telephone Services
 WLL-CDMA Telephone Services
 Internet
 Intelligent Network (IN)
 3G
 IPTV
 FTTH
 WiMax

4. OVERVIEW OF TELECOMMUNICATION
Telephone is a telecommunication device that is used
to transmit and receive electronically or digitally
encoded speech between two or more people
conversing.
Telecommunication networks carry information
signals among entities , which are geographically
apart.
The telecommunication links and switching were
mainly designed for voice communication

5. TELEPHONE EXCHANGE
Telephone exchange is a hub to which all subscribers
are connected.
For smooth working of exchange following unit are
very important
1.Computer Unit
2.Power Supply
3.AC
4.MDF

6. Computer Unit: - it deals with additional services of the
exchange to the customers with the help of computers.
Power Plant:- to feed proper power supply to exchange
AC Plant: - to maintain the continuous temperature + or
– 2 degree Celsius to the digital switch (exchange).

7. MDF(MAIN DISTRIBUTION FRAME)
The fault of telephone number is removed in the
MDF; it is called as Fault Remove Section.
These testing are T.T.Y. testing, Group testing, etc.
The telephone numbers are also disconnected in the
MDF because of some specific reason
ORGANISATION OF THE MDF PARTS:-
Horizontal side
Vertical side

8. HORIZONTAL SIDE
It is subdivided into two parts
Exchange side
Line side
Description of the horizontal side:-
Rack-On the rack, the tags are situated. One rack is
having eight tags.
WEDGE:-If we want to disconnect any two numbers
then we insert a wedge between subscriber side and
exchange side. Here wedge works as insulator made
of plastic.

9. VERTICAL SIDE
The vertical side connected to the underground cable.
This cable is having 100 pairs.
These pair is distributed when we allot the telephone
number to the subscriber.
Vertical side is again subdivided in two parts:
One part is connected with the horizontal side and
another with the subscriber line by using 100 pair
underground cable.

10. NIB(NETWORK INTERNET BACKBONE)
Networking is a key component of any Internet
Services Provider (ISP) operations.
The Internet Backbone refers to the principal data
routes between large, strategically interconnected
networks and core routers in the Internet.
BASIC BLOCKS OF NIB
1.MDF 2.Router 3.DSLAM 4.BNG

11. DSLAM (DIGITAL SUBSCRIBER LINE ACCESS
MULTIPLEXER)
 Maximum capacity of each DSLAM is 480 kbps
 Minimum capacity of each DSLAM is 120 kbps
 480 kbps DSLAM has 16 cards, each card has
48pairs of broad band customers
 One end of the DSLAM is connected to MDF
through the cables which are filled

12. PULSE CODE MODULATION(PCM)
Pulse Code Modulation (PCM) converts analog
signals to a digital format(signal).This process has
four major steps.
1.Filtering
2.Sampling
3.Quantizing
4.Encoding

13. OPTICAL FIBRE
The latest technology that we use today is optical
fibre communication system.
In this system sound energy is converted to light
which is transmitted over optical fibres. This has 99%
efficiency.
The fibre is made up of borosilicate glass.

14. ADVANTAGES OF FIBRE OPTICS :
Fibre 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.

15. OVERVIEW OF BROADBAND TECHNOLOGY
Broadband is the nonspecific term for high-speed
digital Internet access.
Communication of data with different throughput is
feasible by following technologies:
 Narrow Band
2.4Kbps – 128Kbps.
 Broadband
256Kbps – 8000Kbps.
 LAN
1000 – 100Mbps.

16. Broadband communication technology can be divided
broadly in to categories:
 Wire line Technology.
 Wireless Technology.
Wireline Technologies include:
 Digital Subscriber Lines (DSL) on copper
loop.
 Optical Fibre Technologies.
 Cable TV Networks.
 PLC (power line communication).

17. WIRELESS TECHNOLOGIES INCLUDE:
 Satellite Media
 Terrestrial Wireless
 3G Mobile
 Wi-Fi (wireless Fidelity)
 Wi Max.
 FSO (free space optics).

18. GSM
Network and switching subsystem
 NSS is the main component of the public mobile network GSM
 switching, mobility management, interconnection to other networks,
system control
 Components
 Mobile Services Switching Center (MSC)
controls all connections via a separated network to/from a mobile
terminal within the domain of the MSC - several BSC can belong to a
MSC
 Databases (important: scalability, high capacity, low delay)
 Home Location Register (HLR)
central master database containing user data, permanent and semi-
permanent data of all subscribers assigned to the HLR (one provider
can have several HLRs)
 Visitor Location Register (VLR)
local database for a subset of user data, including data about all
user currently in the domain of the VLR

19. GSM : (SYSTEM ARCHITECHTURE)
This system structured hierarchically as shown:
 It consist of one administrative region, which is assigned
to a MSC(Mobile Switching Center).
 Each administrative Region is made up of atleast one
Location Area(LA). LA is also called the visited area.
 An LA consists of several cell groups.
 Each cell group is assigned to a base station
controller(BSC).
 Cells of one BSC may belong to different LA’s.

21. OPERATION SUBSYSTEM
 The OSS (Operation Subsystem) enables centralized operation,
management, and maintenance of all GSM subsystems
 Components
 Authentication Center (AUC)
 generates user specific authentication parameters on request of a
VLR
 authentication parameters used for authentication of mobile
terminals and encryption of user data on the air interface within the
GSM system
 Equipment Identity Register (EIR)
 registers GSM mobile stations and user rights
 stolen or malfunctioning mobile stations can be locked and
sometimes even localized
 Operation and Maintenance Center (OMC)
 different control capabilities for the radio subsystem and the network
subsystem

22. TEMPORARY DATA PERMANENT
DATA
- Temporary Subscriber Identity Permanent Subscriber
Identity
- Current Location Key/Algorithm for
Authentication.
- Ciphering Data
Provides access to the GSM n/w
Consists of
Mobile equipment (ME)
Subscriber Identity Module (SIM)

23. THE GSM NETWORK ARCHITECTURE
 Time division multiple access-TDMA
 124 radio carriers, inter carrier spacing
200khz.
 890 to 915mhz mobile to base - UPLINK
 935 to 960mhz base to mobile - DOWNLINK
 8 channels/carrier

24.  GSM combines FDM and TDM: bandwidth is
subdivided into channels of 200khz, shared
by up to eight stations, assigning slots for
transmission on demand.