Bharti Airtel is India's largest mobile network operator. It provides 2G, 3G, and 4G services across India and internationally. The document discusses the evolution of mobile communication systems from 1G to 4G and provides an overview of GSM (Global System for Mobile communications) including its history, components, specifications, and advantages such as worldwide connectivity, high capacity, and security functions. It describes the network subsystem comprising the MSC, HLR, VLR, AuC, EIR, and GMSC which perform call processing and subscriber management. The radio subsystem including the BSC and BTS is also outlined.

1. NETWORK OPERATION AND
MAINTENANCE OF GSM
Under Guidance of
Mr. Rakesh Gusain
Switch Lead, Delhi
BY
Unique Kumar
9034131922
Done in

2. Introduction to the Company
• Bharti Airtel Limited, commonly known as Airtel, is an
communications services company headquartered at New
Delhi, India. It operates in 20 countries across South Asia,
Africa and the Channel Islands.
• It is the largest cellular service provider in India, with 183.61
million subscribers as of November 2012. Airtel is the third
largest in-country mobile operator by subscriber base,
behind China Mobile and China Unicom.
• Airtel is the largest provider of mobile telephony and second
largest provider of fixed telephony in India, and is also a
provider of broadband and subscription television services. It
offers its telecom services under the Airtel brand, and is
headed by Sunil Bharti Mittal.

3. 1946
• First Car Phone by St. Louis.
1973
• First hand-held mobile phone by Martin Cooper.
1980’s
• 1G Cellular technology launched.
• TACS , NMT , AMPS etc. analog systems launched in
American & UK countries.
1990’s
• Digital 2G Cellular technology launched.
• GSM , CDMA etc. launched with GSM being the
standard.
History

4. Evolution of Mobile communication
systems
High data rates
(384kbps- 14.4 Mbps)
+ 2nd gen. services
1990 2000
Analog speech Digital speech +
low rate data
(≤ 64 kbps)
-
1980
1st Generation 2nd Generation 3rd Generation

5. 1G
Analog in nature.
Only speech , no data
services..
International Roaming
not possible..
2G
Digital in nature.
Speech + Data services.
( SMS Possible)
Globalised..
International roaming
possible..
In 2001 the first commercial launch of 3G was done in
Japan. With 3G following services are available :
 Video Conferencing
 online games
 net surfing..

6. Intoduction to GSM
• Global System for Mobile (GSM) is cellular standard developed to cater
voice services and data delivery using digital modulation.
• Its ubiquity makes international roaming very common between mobile
phone operators, enabling subscribers to use their phones in many parts of
the world. GSM differs from its predecessors in that both signaling and
speech channels are digital,
• GSM also pioneered a low-cost (to the network carrier) alternative to voice
calls, the short message service (SMS, also called "text messaging")
• Newer versions of the standard were backward-compatible with the
original GSM phones. For example,of the standard added packet data
capabilities, by means of General Packet Radio Service (GPRS). Release '99
introduced higher speed data transmission using Enhanced Data Rates for
GSM Evolution (EDGE).

7. GSM in World
Figures: March, 2005
37%
1%
4%43%
4%
3%
3%
3% (INDIA)
3%
Arab World
Asia Pacific
Africa
East Central Asia
Europe
Russia
India
North America
South America

8. GSM in India

9. GSM Services
Tele-services
Bearer or Data Services
Supplementary services

10. Tele Services
• Telecommunication services that enable
voice communication
via mobile phones
• Offered services
- Mobile telephony
- Emergency calling

11. Bearer Services
• Include various data services for information transfer
between GSM and other networks like PSTN, ISDN etc at
rates from 300 to 9600 bps
• Short Message Service (SMS)
–up to 160 character alphanumeric data transmission
to/from the mobile terminal
• Unified Messaging Services(UMS)
• Group 3 fax
• Voice mailbox
• Electronic mail

12. Supplementary Services
Call related services :
• Call Waiting- Notification of an incoming call while on the handset
• Call Hold- Put a caller on hold to take another call
• Call Barring- All calls, outgoing calls, or incoming calls
• Call Forwarding- Calls can be sent to various numbers defined by the user
• Multi Party Call Conferencing - Link multiple calls together
• CLIP – Caller line identification presentation
• CLIR – Caller line identification restriction
• CUG – Closed user group

13.  Communication
– mobile, wireless communication, support for voice and data
services
 Total mobility
– international access, chip-card enables use of access points of
different providers.
 Worldwide connectivity
– one number, the network handles every location.
 High capacity
– better frequency efficiency, smaller cells, more customers per cell.
 High transmission quality
– high audio quality and reliability for wireless, uninterrupted phone
calls at higher speeds (e.g., from cars, trains).
• Security functions
– access control, authentication via chip-card and PIN
Advantages of GSM

14. GSM Specifications
• RF Spectrum
GSM 900
Mobile to BTS (uplink): 890-
915 MHz
BTS to Mobile(downlink):935-
960 MHz
Bandwidth : 2* 25 MHz
GSM 1800
Mobile to BTS (uplink): 1710-
1785 MHz
BTS to Mobile(downlink) 1805-
1880 MHz
Bandwidth : 2* 75 MHz
• Carrier Separation : 200 KHz
• Duplex Distance : 45 MHz
• No. of RF carriers : 124
• Access Method :
TDMA/FDMA
• Modulation Method : GMSK
• Modulation data rate :
270.833 Kbps

16. Network subsystem
Performs call processing and subscriber related
functions. It includes:
MSC: Mobile Switching Centre
HLR: Home Location Register
VLR : Visitor Location Register
AuC: Authentication Centre
EIR: Equipment Identity Register
GMSC:Gateway MSC.

17. Network subsystem
Performs call processing and subscriber related
functions. It includes:
MSC: Mobile Switching Centre
HLR: Home Location Register
VLR : Visitor Location Register
AuC: Authentication Centre
EIR: Equipment Identity Register
GMSC:Gateway MSC.

18. Mobile station (MS)
SIM is a removable module that goes
into mobile set. Each SIM has a unique
number called IMSI number.
Stores user addresses
-IMSI
- MSISDN
-Temporary addresses for location,
roaming, etc
Mobile Equipment Capabilities
Encryption capability
Frequency capability
Short messages service capability.
Location updates.
Voice and data recognition.
Identified by IMEI no.( International Mobile
Equipment Identity)

19. • It is included in the GSM system for call-switching. Its overall purpose is the same
as that of any telephone exchange.
The functions carried out by the MSC are listed below:
• Call Processing
Includes control of data/voice call setup, inter-BSS and inter-MSC handovers and
control of mobility management (subscriber validation and location).
• Operations and Maintenance Support
Includes database management, traffic metering and measurement, and a man–
machine interface.
• Internetwork Interworking
Manages the interface between the GSM network and the PSTN.
When the MSC provides the interface with the other networks in the
GSM network it is known as a Gateway MSC.
Network subsystem
Mobile switching centre

20. Reference database for
subscriber parameters.
 Subscriber ID (IMSI & MSISDN).
 Current location of subscriber.
 Subscriber status
(registered/unregistered)
 Authentication key and AUC
functionality.
 Mobile subscriber roaming
number.
Home location register
Network subsystem

21. • It provides local database for the
subscribers wherever they are
physically located within a PLMN,
this may or may not be the
“home” system. It is a local
database and contains copy of
most of the data stored in HLR.
It contains:
• Mobile status(busy/free/no ans)
• Location area identity(LAI)
• TMSI AND MSRN .
Network subsystem
Visitor location register

22. • It provides authentication and encryption
parameters for verification of subscriber identity.
• It ensures confidentiality of each cell.
• It protects network operators from frauds in
today's cellular world.
• It is associated with HLR.
• The authentication process will usually take place
each time the subscriber “initializes” on
the system.
Authentication centre
Network subsystem

23. • The EIR contains a centralized database for validating the
International Mobile Equipment Identity (IMEI).
• It contains three lists:
• White List
Contains those IMEIs which are known to have been assigned to
valid MS equipment.
• Black List
• Contains IMEIs of MS which have been reported stolen or which
are to be denied service for some other reason.
• Grey List
Contains IMEIs of MS which have problems (for example, faulty
software). These are not, however, sufficiently significant to
warrant a ‘‘black listing”.
EQUIPMENT IDENTITY REGISTER
Network subsystem

24. Radio Subsystem
• Management of radio
network and is controlled
by a MSC . One MSC
controls many radio
subsystem.
It consists of :
 BSC: Base station
controller.
 BTS: Base transceiver
station.

25. base station controller
 It is connected to MSC.
 Controls one or more BTS.
 Switches traffic and
signaling to/from BTSs and
MSC.
 Connects terrestrial circuits
and channels on air
interface.
 Controls handover
performed by BTS.
 Frequency allocation and
power control.
RADIO
subsystem

26. base transceiver station
• Maintains air interface and
minimize transmission
problems.
• Paging information.
• Radio level power control.
• BTS identification.
• Ciphering
• Speech processing.
RADIO subsystem

27.  Dynamic monitoring and controlling of
network.
 operation and maintenance data function.
 Configuration management.
 Fault report and alarm handling.
 Performance supervision.
 Storage of software and data.
 Stores data for minimum one year.
OPERATION AND MAINTENANCE SUBSYSTEM

28. Mobile Identification numbers/ mobile identifiers
1. International Mobile Equipment Identity
 Uniquely identifies the mobile equipment.
 A 15 digit hierarchical address assigned to user at time of manufacturing.
2. International Mobile Subscriber Identity
 Uniquely identifies the user (SIM CARD).
 A 15 digit hierarchical address assigned by operator to SIM card upon
subscription .

29. Continued…
3.Mobile Subscriber ISDN Number (MSISDN)
4.TEMPORARY ADDRESS

30. MNP

31. 1. SERVICE OPERATOR PORTABILITY
2. LOCATION PORTABILITY
3. SERVICE PORTABILITY

32. SERVICE OPERATOR PORTABILITY
• retain the same geographic number when changing
from one operator or service provider to another.
• Currently being used in INDIA

33. • Customer to retain the same geographic number
when moving from one location to another
• Location portability would allow customers to
take their number when they move to a
geographic location outside of the original rate
center
LOCATION PORTABILITY

34. NUMBER PORTABILITY DATABASE
• The number portability database (NPDB) keeps track of the ported
numbers and their respective service providers
• The NPDB can be either centralized or distributed
• In the centralized model, there exists a single reference database
• In the distributed model there exist multiple databases, each containing
subsets of the total data, e.g. only the numbers assigned to particular
service provider

36. • The Originating Network receives a Msg/call from
the caller and send a query to a centrally
administered Number Portability Database (NPDB)
• The NPDB returns the routing number associated
with the dialed directory number.
• The Originating Network uses the routing number
to route the call to the new serving network.

39. CHALLENGES
• Customer’s value added services will be lost
• What for fixed lines? Local number portability
includes some thing as Standard Transfer, Like-
for-Like Transfer. These are really challenging to
setup and bill accordingly.

40. ADVANTAGES DIS ADVANTAGES
• Can retain existing mobile
number.
• Just for a small fee of 19/-
• You can switch from GSM
to CDMA and vice versa
 Change in location having
same number
 cannot switch again for the
next 90 days.
 Change in hand set when
change in platform

41. END