This presentation provides an overview of the Global System for Mobile (GSM) communications. It discusses the architecture of GSM including the mobile station, base station subsystem, and network subsystem. It also covers specifications such as frequency bands and carrier spacing, security features like encryption, and applications like telemetry systems. The presentation concludes by looking at the future of GSM including data rate improvements through technologies like GPRS, EDGE, and the transition to 3G standards.

1. PRESENTATION ON
NAME : BHANU PRATAP SINGH
BRANCH : E.I.
ROLL NO . : 090105012

2. CONTENTS
 INTRODUCTION
 ARCHITECTURE
 SPECIFICATIONS
 SECURITY
 CHARACTERISTICS
 APPLICATIONS
 FUTURE

3. INTRODUCTION
 Global System for Mobile (GSM) is a second generation cellular
standard developed to cater voice services and data delivery using
digital modulation.
 Aim Of GSM is to replace the incompatible analog system .
 Today many providers all over the world use GSM (more than 135
countries in Asia, Africa, Europe, Australia, America)

4. ARCHITECTURE

5. ARCHITECTURE
 Mobile Station
 Mobile Equipment (ME)
 Subscriber Identity Module (SIM)
 Base Station Subsystem (BSS):
 Base Transceiver Station
 Base Station Controller
 Network Subsystem:
 Mobile Switching Center (MSC)
 Home Location Register (HLR)
 Visitor Location Register (VLR)
 Authentication Center (AUC)
 Equipment Identity Register (EIR)

6. MOBILE STATION (MS)
• The Mobile Station is made up of two entities:
Mobile Equipment (ME)
o The Mobile Equipment is the hardware used
by the subscriber to access the network .
o Uniquely identified by an IMEI (International
Mobile Equipment Identity)
Subscriber Identity Module (SIM)
o Smart card containing the International Mobile
Subscriber Identity (IMSI)
o Allows user to send and receive calls and
receive other subscribed services
o Protected by a password or PIN

7. BASE STATION SUBSYSTEM
 Base Station Subsystem is
composed of two parts :
 1) Base Transceiver Station (BTS)
 2) Base Station Controller (BSC)
• Base Transceiver Station
(BTS)
 Houses the radio transceivers that define a
cell
 Handles radio-link protocols with the Mobile
Station

8. Base Station Controller (BSC)
 Manages Resources for BTS ,
 Handles call set up,
 Location update,
 Handover for each MS.

9. NETWORK SUBSYSTEM
 Mobile Services Switching Center (MSC)
MSC performs following functions :
 Switching and call routing
 Charging
 Service provisioning
 Communication with HLR
 Communication with the VLR
 Communication with other MSCs
 Control of connected BSCs
 Direct access to Internet services
 Home Location Registers (HLR) :
 Contains administrative information of each subscriber
 Most important database

10. NETWORK SUBSYSTEM
 Visitor Location Registers (VLR)
o tracks which customers have the phone on and ready to
receive a call
o periodically updates the database on which phones are
turned on and ready to receive calls
 Authentication Center (AUC)
o mainly used for security
o data storage location and functional part of the network
 Equipment Identity Register (EIR)
- Database that is used to track handsets using the IMEI ,Made up
of three sub-classes: The White List, The Black List and the Gray
List
o Optional database

11. GSM SPECIFICATIONS
• GSM systems use radio frequencies between 890-915 MHz for
receive and between 935-960 MHz for transmit.
• RF carriers are spaced every 200 kHz, allowing a total of 124
carriers for use.
• An RF carrier is a pair of radio frequencies, one used in each
direction.
• Transmit and receive frequencies are always separated by 45
MHz .

12. SECURITY IN GSM
 On air interface, GSM uses encryption and TMSI instead of
IMSI.
 SIM is provided 4-8 digit PIN to validate the ownership of SIM
 3 algorithms are specified :
- A3 algorithm for authentication
- A5 algorithm for encryption
- A8 algorithm for key generation

13. CHARACTERISTICS OF GSM STANDARD
 Fully digital system using 900,1800 MHz frequency band.
 TDMA over radio carriers(200 KHz carrier spacing.
 User/terminal authentication for fraud control.
 Encryption of speech and data transmission over the radio
path.
 Full international roaming capability.
 Low speed data services (up to 9.6 Kb/s).
 Compatibility with ISDN.
 Support of Short Message Service (SMS).

14. ADVANTAGES OF GSM OVER ANALOG
SYSTEM
 Capacity increases
 Reduced RF transmission power and longer battery life.
 International roaming capability.
 Better security against fraud (through terminal validation and user
authentication.

15. GSM APPLICATIONS
 Telemetry System
- Fleet management
- Automatic meter reading
- Toll Collection
 Value Added Services

16. FUTURE OF GSM
o 2nd Generation
 GSM -9.6 Kbps (data rate)
o 2.5 Generation ( Future of GSM)
 HSCSD (High Speed circuit Switched data)
 Data rate : 76.8 Kbps (9.6 x 8 kbps)
 GPRS (General Packet Radio service)
 Data rate: 14.4 - 115.2 Kbps
 EDGE (Enhanced data rate for GSM Evolution)
 Data rate: 547.2 Kbps (max)
o 3 Generation
 WCDMA(Wide band CDMA)
 Data rate : 0.348 – 2.0 Mbps

17. THANK
YOU