GSM AND VAS

8/2/2019 GSM AND VAS

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RAHUL PARMAR

09ITMG1165ECE


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Global System for Mobile (GSM) is a secondgeneration cellular standard developed tocater voice services and data delivery usingdigital modulation


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Tele-services Bearer or Data Services

Supplementary services


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Telecommunication services that enable voicecommunication via mobile phones

Offered services

- Mobile telephony

- Emergency calling


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Include various data services for informationtransfer between GSM and other networks likePSTN, ISDN etc at rates from 300 to 9600 bps

Short Message Service (SMS)

up to 160 character alphanumeric datatransmission to/from the mobile terminal

Unified Messaging Services(UMS) Group 3 fax

Voice mailbox

Electronic mail


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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 bythe user

Multi Party Call Conferencing - Link multiple calls together

CLIPCaller line identification presentation CLIRCaller line identification restriction

CUGClosed user group


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4/26/2012 ITM, Gurgaon 7

BSC

BSC

MSC

MS

MS

BTS

BTS

GMSC

EIR

AUC

HLR

VLR


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Mobile Station (MS)Mobile Equipment (ME)

Subscriber Identity Module (SIM)

Base Station Subsystem (BSS)Base Transceiver Station (BTS)Base Station Controller (BSC)

Network Switching Subsystem(NSS)Mobile Switching Center (MSC)

Home Location Register (HLR)

Visitor Location Register (VLR)Authentication Center (AUC)

Equipment Identity Register (EIR)


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The Mobile Station is made up of two entities:

1. Mobile Equipment (ME)

2. Subscriber Identity Module (SIM)


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Mobile Equipment Portable,vehicle mounted, hand held device

Uniquely identified by an IMEI (InternationalMobile Equipment Identity)

Voice and data transmission Monitoring power and signal quality of

surrounding cells for optimum handover

Power level : 0.8W

20 W 160 character long SMS


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Subscriber Identity Module (SIM) Smart card contains the International Mobile Subscriber

Identity (IMSI)

Allows user to send and receive calls and receive othersubscribed 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 phonecontains key

information to activate the phone


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Base Station Subsystem is composed of two parts thatcommunicate across the standardized Abis interface

allowing

operation between components made by different

suppliers

1. Base Transceiver Station (BTS)2. Base Station Controller (BSC)


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Base Transceiver Station (BTS):

Encodes,encrypts,multiplexes,modulates and feeds the RF

signals to the antenna.

Frequency hopping

Communicates with Mobile station and BSC

Consists of Transceivers (TRX) units


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Base Station Controller (BSC) Manages Radio resources for BTS Assigns Frequency and time slots for all MSs in

its area Handles call set up Transcoding and rate adaptation functionality Handover for each MS Radio Power control It communicates with MSC and BTS


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Mobile Switching Center (MSC) Heart of the network Manages communication between GSM and other networks Call setup function and basic switching

Call routing Billing information and collection Mobility management

- Registration- Location Updating

- Inter BSS and inter MSC call handoff MSC does gateway function while its customer roams to

other network by using HLR/VLR.


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Home Location Registers (HLR)- permanent database about mobile subscribers in a large service

area(generally one per GSM network operator)

- database contains IMSI,MSISDN,prepaid/postpaid,roamingrestrictions,supplementary services.

Visitor Location Registers (VLR)- Temporary database which updates whenever new MS enters its area, by

HLR database

- Controls those mobiles roaming in its area

- Reduces number of queries to HLR- Database contains IMSI,TMSI,MSISDN (number normally dialed to

connect a call to the mobile phone ),MSRN (mobile Station RoamingNumber), Location Area,authentication key


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Authentication Center (AUC)- Protects against intruders in air interface

- Maintains authentication keys and algorithms andprovides security triplets ( RAND, SRES, Kc)

- Generally associated with HLR

Equipment Identity Register (EIR)- Database that is used to track handsets using the

IMEI (International Mobile Equipment Identity)

- Made up of three sub-classes: The White List, TheBlack List and the Gray List

- Only one EIR per PLMN (Public Land MobileNetwork)


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RF SpectrumGSM 900Mobile to BTS (uplink): 890-915 Mhz

BTS to Mobile(downlink):935-960 Mhz

Bandwidth : 2* 25 MhzGSM 1800

Mobile to BTS (uplink): 1710-1785 Mhz

BTS to Mobile(downlink) 1805-1880 MhzBandwidth : 2* 75 Mhz


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Carrier Separation : 200 Khz Duplex Distance : 45 Mhz

No. of RF carriers : 124

Access Method : TDMA/FDMA Modulation Method : GMSK (Gaussian

Minimum Shift keying)

Modulation data rate : 270.833 Kbps


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Fully digital system using 900,1800 MHz frequencyband.

TDMA over radio carriers(200 KHz carrier spacing.

8 full rate or 16 half rate TDMA channels percarrier.

User/terminal authentication for fraud control.

Encryption of speech and data transmission overthe radio path.

Full international roaming capability.

Low speed data services (upto 9.6 Kb/s). Compatibility with ISDN.

Support of Short Message Service (SMS).


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Mobile telephony GSM-R

Telemetry System

- Fleet management- Automatic meter reading

- Toll Collection

- Remote control and fault reporting of DGsets

Value Added Services


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To a housewife, MVAS is an SMS which enables her

to participate in Indias Got Talent.

To a student latest music track which he/she uses for

his/her ringtone or updating his/her facebook on thego.

For the farmer it is mandi rates which get updated onhis mobile.


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Entertainment VAS These generate high volume and high usage. E.g.

CRBT, Jokes etc.

Information VAS These services provide useful services to users.

E.g. Stock updates, News, Education.

Commerce VAS It involves transactions using mobile phones. E.g.

Money transfer.


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Decrease in ARPU.

Need for differentiation.

Increasing need.

Demand from consumers


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Infrastructure Sharing Managed Services

Enterprise Telecom

Rural Telephony


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Rural VAS can create two basic niches in ruralmarket:

Connectivity: Enables agricultural inputs likeMandi rates, Weather etc. Social welfarenetworks could go forward in enhancing thelife of rural users.

Entertainment: Creating another portal for

entertainment starved rural India


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THANK YOU

Documents

GSM AND VAS