Islamic University-Gaza Faculty of Engineering Electrical & Computer Engineering Department

1. Islamic University-Gaza Faculty of Engineering Electrical & Computer Engineering Department Global System for Mobile Communication GSM Group Alaa Al-Zatma Hosam Al-Awaj Obada Abdullah Supervisor Dr. Basil Hamad

2. Contents • Introduction to GSM • Services provided by GSM • Architecture of GSM Network • Cells & its types • Calling with GSM • Security of GSM • Conclusion

3. Introduction to GSM • GSM is a digital cellular communications system • In early of 1982, the standard GSM was formed. • More than 800 million end users in 193 countries over 550 networks • Palestine • JAWWAL use GSM

4. More .. • Provides a best cellular service in best voice and speed of connection • More security • Compatibility • Use TDMA or CDMA to increase capacity

5. Services provided by GSM • Call waiting & Call hold • If you are using the phone, Call Waiting will alert you to a second caller. You need never miss an incoming call. • Use Call Hold to put the person you are talking to on hold so you can call another party, and then switch between the two calls. • Call forwarding To divert incoming calls to another number. • Calling line identity (CLI) CLI displays the number (name if stored on your phone) of the incoming call.

6. Cont.. • SMS (short messaging service) allow you to send & receive text messages on your phone • Data Services • receive and send data • GSM currently has a data transfer rate of 9.6 kbps. • New developments which push up data transfer rates for GSM users like: • HSCSD (high speed circuit switched data) • GPRS (general packet radio service) are now available.

7. Authentication Center: • used for security purposes • provides the parameters • needed for authentication and • encryption functions Architecture of GSM Network • Visitor Location Register: • contains temporary • information from • a subscriber’s HLR • Mobile services Switching Center • Backboneof GSM Network • Advanced digital divider • manager of BSCs • Manage, prepare, control, • and passing the call through • the GSM network • Mobile Station: • Consist of: • mobile equipment • a smart card called the • Subscriber Identity • Module (SIM) • Base Transceiver Station: • Control the frequencies • Its task is transmitting • & receiving for mobile • Home Location Register: • It has a very important Database • Store information about • subscribers belonging the • coverage area of MSC • stores the current location of • these subscribers and the • services to which they have access • Gateway Mobile services Switching Center : • It is an interface between the mobile cellular network and the PSTN • Manage the outer • communications (Roaming) • Base Station Controller: • controls a group of BTS • manages BTS radio • resources • It is principally in charge of handovers • Equipment Identity Register: • used for security purposes • containing information about the • mobile equipments

8. Cells • The cell: • It’s the main unit of cellular system • Identified by its Cell Global Identity number (CGI) • Corresponds to the radio coverage of BTS • Types of cells are used: • Macro cells: large cells for remote and sparsely populated areas • Micro cells: • used for densely populated areas • splitting the existing areas into smaller cells

9. Location Area (LA) • Defined as group of cells in the network • The subscriber's location is known in this area and store in VLR • If the subscriber transported from Location to another VLR must have a report of subscriber's new location

10. Calling with GSM .. • Your mobile call the cellular phone’s network and send it to nearest tower • The tower transmit the waves to the switchboard • If you call Telephone the switchboard transmit your call to PSTN • If you call another mobile, then the switchboard transmit the wave to the nearest tower of another mobile • If the caller are increase, the company must be increase the towers to make fine calling • So you can see small towers in high buildings and centers, etc..

11. BSC BSC BTS BTS BSC BSC BTS BTS HLR EIR GMSC Handover • Handover is the switching of an on going call to a different channel or cell. • Type of handover there are four different type of handover in which involve transferring a call between : SIM VLR PSTN ISDN,PSPDN CSPDN M S C MSC MSC ME Mobile Station Abis Base Station Subsystem Network Subsystem

12. Authentication & Security Why authentication? • Authentication involves two functional entities, the SIM card, (AuC). • Each subscriber has a secret key which copied in the SIM card, (AuC). • The AuC generates a random number and it sends to the mobile. • Both the mobile and the AuC apply these number to the ciphering algorithm called A3, to calculate a third number • The mobile send the calculated number to the AuC • If the two calculated number is the same then the subscriber is authenticated

13. cont. • Another level of security is performed on the mobile equipment itself • each GSM equipment is identified by a unique (IMEI) number. • A list of IMEIs in the network is stored in the (EIR) and they will divided in to three list • White-listed the equipment is allowed to connect to the network. • Grey-listed the equipment is under observation from the network for possible problems. • Black-listed the equipment has either been reported stolen, or is not type approved; The terminal is not allowed to connect to the network.

14. Conclusion • We see the architecture of GSM network and the main function of the main part of this network. • each dialed call must pass through BTS;BSC and MSC. • GSM system characterized by high mobility so any one can travel during the time of the call. • Another important characteristic of GSM is the high security; so no one can listen to your call this is because of the random number. • There is no affect genetic material

15. Reference • http://www.myjawwal.com • http://www.luc.ac.be/~hbaerten/gsm/ • http://www.gsmworld.com/ • http://www.gsmag.com/ • http://www.mobileworld.org/ • http://kbs.cs.tu-berlin.de/~jutta/gsm/gsm-list.html • http://www.howstuffworkcom

16. THANK YOU