1. Dept. of Business Administration
Conducted by
Md.Mahbobor Rahaman
Lecturer(MIS)
Dept. of Business Administration
Leading University

2. GSM
GSM (Global System for Mobile communication) is a digital mobile telephony system that is widely used in Europe and other parts of the world. GSM uses a variation of time division multiple access (TDMA) and is the most widely used of the three digital wireless telephony technologies (TDMA, GSM, and CDMA). GSM digitizes and compresses data, then sends it down a channel with two other streams of user data, each in its own time slot. It operates at either the 900 MHz or 1800 MHz frequency band.

3. The Mobile Telephone System
First-Generation Mobile Phones: Analog Voice
Second-Generation Mobile Phones: Digital Voice
Third-Generation Mobile Phones: Digital Voice and Data

4. History of GSM
During the early 1980s, analog cellular telephone systems were experiencing rapid growth in Europe .
Commercial service was started in mid-1991, and by 1993 there were 36 GSM networks in 22 countries.
Although standardized in Europe, GSM is not only a European standard.
The acronym GSM now aptly stands for Global System for Mobile communications.

5. Advanced Mobile Phone System
(a) Frequencies are not reused in adjacent cells.
(b) To add more users, smaller cells can be used.

6. GSM architecture

7. Global System for Mobile Communications Interworking Unit (GIWU)
Mobile Station
Base Station
Sub system
Network
Sub system
Global System for Mobile Communications Interworking Unit (GIWU)

8. Base Station Subsystem
Two parts,
the Base Transceiver Station (BTS) and
the Base Station Controller (BSC).
The Base Transceiver Station houses the radio tranceivers that define a cell and handles the radio-link protocols with the Mobile Station.
The Base Station Controller manages the radio resources for one or more BTSs.
It handles radio-channel setup, frequency hopping, and handovers.
The BSC is the connection between the mobile station and the Mobile service Switching Center (MSC).

9. Mobile Station
1. The mobile station (MS) consists of the mobile equipment (the terminal) and
2. a smart card called the Subscriber Identity Module (SIM).
The mobile equipment is uniquely identified by the International Mobile Equipment Identity (IMEI).
The SIM card contains the International Mobile Subscriber Identity (IMSI) used to identify the subscriber to the system, a secret key for authentication, and other information.

10. Network Subsystem 1. Mobile services Switching Center (MSC).
2. Home Location Register (HLR) and
3 Visitor Location Register (VLR)
4. Equipment Identity Register (EIR)
5. Authentication Center (AuC)
The central component is the Mobile services Switching Center (MSC). It acts like a normal switching node of the PSTN or ISDN, and handle a mobile subscriber, such as registration, authentication, location updating, handovers, and call routing to a roaming subscriber.
The Home Location Register (HLR) and Visitor Location Register (VLR), together with the MSC, provide the call-routing and roaming capabilities of GSM.
The HLR contains all the administrative information of each subscriber registered in the corresponding GSM network, along with the current location of the mobile.

11. Network Subsystem
The Visitor Location Register (VLR) contains selected administrative information from the HLR, necessary for call control.
Note that the MSC contains no information about particular mobile stations --- this information is stored in the location registers.
The Equipment Identity Register (EIR) is a database that contains a list of all valid mobile equipment on the network.
The Authentication Center (AuC) is a protected database that stores a copy of the secret key stored in each subscriber's SIM card, which is used for authentication and encryption over the radio channel.

12. Third-Generation Mobile Phones: Digital Voice and Data
Basic services an IMT-2000 network should provide
High-quality voice transmission
Messaging (replace , fax, SMS, chat, etc.)
Multimedia (music, videos, films, TV, etc.)
Internet access 8

13. Mobile phone contents
Radio frequency - receiver and transmitter Digital signal processing Analogue / digital conversion Control processor SIM or USIM card Power control and batter

14. Mobile phone network registration
When the mobile phone is turned on the phone does not have an allocated channel, and time slot.
Registration is a process by which a newly switched on mobile can communicate with the network and set up the standard communication.
After turn on first is to communicate with the base station, and next the mobile has to register to allow it to have access to and use the network.

15. Mobile phone network registration
In order to make contact with the base station the mobile uses a control channel.
Authentication Centre (AuC) is checked to provide authentication and encryption parameters that verify the user's identity and ensure the confidentiality of each call protecting users and network operators from fraud.

16. Mobile phone network registration
If everything is OK then the mobile is registered.
Once registered Home Location Register (HLR) and the Visitors Location Register (VLR) are required to keep track of the mobile so that the network knows where it is at any time so that calls can be routed to the correct base station.

17. Handover and handoff
The mobile handset moves out of one cell to the next, it must be possible to hand the call over from the base station of the first cell, to that of the next with no discernable disruption to the call.
There are two terms for this process: handover is used within Europe, whereas handoff is the term used in North America.
Parameters Determine handovers:
The signal strength of the base station
The signal strengths of the surrounding stations.
The availability of channels

18. Types of Handover Hard handover Soft handover Softer handover
Hard handover is one where an existing connection must be broken before the new one is established.
A new connection is established before the old one is released.
A signal is replaced by a stronger signal from a different sector under the same base station.

19. Types of Handover

20. Types of Handover

21. GSM Network Structure GP Network GP and Robi MSC are interconnected
Intelligent
Network (IN)
GP Network
GP and Robi MSC
are interconnected
Robi Network
Intelligent
Network (IN)

22. GSM Network Structure Bl Network GP and Robi MSC are interconnected
Intelligent
Network (IN)
Bl Network
GP and Robi MSC
are interconnected
Airtel Network
Intelligent
Network (IN)

23. GSM Network Structure Teletalk Network GP and Robi MSC
Intelligent
Network (IN)
Teletalk Network
GP and Robi MSC
are interconnected
GP Network
Intelligent
Network (IN)