28-12-2012, 06:52 PM
Presentation on GSM Network
1GSM Network.ppt (Size: 514 KB / Downloads: 21)
What is GSM ?
Global System for Mobile (GSM) is a second generation cellular standard developed to cater voice services and data delivery using digital modulation
GSM: History
• Developed by Group Spéciale Mobile (founded 1982) which was an initiative of CEPT ( Conference of European Post and Telecommunication )
• Aim : to replace the incompatible analog system
• Presently the responsibility of GSM standardization resides with special mobile group under ETSI ( European telecommunication Standards Institute )
Full set of specifications phase-I became available in 1990
• Under ETSI, GSM is named as “ Global System for Mobile communication “
• Today many providers all over the world use GSM (more than 135
countries in Asia, Africa, Europe, Australia, America)
• More than 1300 million subscribers in world and 45 million subscriber in India.
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
Subscriber Identity Module (SIM)
Smart card contains the International Mobile Subscriber Identity (IMSI)
Allows user to send and receive calls and receive other subscribed services
Encoded network identification details
- Key Ki,Kc and A3,A5 and A8 algorithms
Protected by a password or PIN
Can be moved from phone to phone – contains key information to activate the phone
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).
Encryption capability for information security and privacy.
Compatibility with ISDN,leading to wider range of services