Post on 26-Jun-2015
An Overview
Abhi MaheshwariVII SemECEJIET Jodhpur
Founded in 2009 A Joint Venture between Unitech
Group [India] and Telenor [ Norway ]
Telenor , the sixth largest mobile operator in the world, holds a 67.25 % majority stake in Uninor .
Scope of Training
Basics of Communication
GSM Technology and Architecture
Mobile Number Portability , implementation and testing
GSM stands for
Global System for Mobile Communications
GSM : Some facts GSM evolved because of the need for a
standard mobile telephone system that could be deployed across Europe
It uses the Gaussian Minimum Shift Keying
[ GMSK ] technique for modulation
In India , cellular services started around 1995
GSM networks operate in the 900 MHz or 1800 MHz bands
Why GSM ? Dominant global market share
Large number of infrastructure and handset vendor’s giving advantage in terms of price and other commercial terms
Wide choice of handsets
Seamless interoperability between networks and handsets
Global footprint for international roaming including SMS, data and other value added services
GSM ARCHITECTURE
PSTNGMSC
MSC
HLR
AUC
VLR
EIR
BSC
BTS
Network Switching System
BSS
ME
Mobile StationBTS
BTS
GSM ARCHITECTURESIMPLIFIED VIEW
MSCPSTN
BSCBSC
BTS BTS
Mobile Station (MS)
MobileStation
Mobile Equipment
Subscriber Identity Module [ SIM ]
Mobile station provides user access to GSM network for Voice & Data
Subscriber data is read from a SIM card that plugs into MS Each MS has a unique number called as IMEI number, Mobile Transmit and Receive voice at 13 KB/s over air interface
Base Transceiver Station (BTS)
•Speech processing (channel coding, interleaving, and burst formatting)
•Generation of alarms and statistics
• Baseband/Radio frequency transformation
•Air interface signalling
•Ciphering
BSC - Base Station Controller
BSC - Base Station Controller Connection establishment between
the MS and the NSS
Mobility management
Statistical raw data collection
Several BTSs are connected to the BSC
BSC Manages channel allocation, handovers and release of channels at connected BTSs
MSC – Mobile Switching Centre
MSC – Mobile Switching Centre Exchange where calls are established, maintained and released
Database for all subscribers and their associated features.
Communicates with the BSCs MSC is weighted on the
number of subscribers it can support.
HLR - Home Location Register
HLR
MSC has all subscriber database stored in HLR
HLR has all permanent subscriber database
MSC communicates with HLR to get data for subscribers on call
HLR will have the series of all subscriber numbers, which may not be activated or issued .
MSC
VLR – Visiting Location Register A subscription when activated is
registered in VLR VLR has all the subscriber numbers
which are active. VLR has a temporary database of
all active subscribers (on/off, location information)
HLR
MSC VLRVLR
VLR – Visiting Location Register
MSC MSCVLRVLR
HLR
VLR
MSC communicates with HLR for subscribers coming from different MSCs. If the subscriber is found valid, then it registers the subscriber in the VLR
AUC – Authentication Centre Authentication is a process by
which a SIM is verified Secret data and the verification
process algorithm are stored in AUC
AUC is the element which carries out the verification of the SIM
AUC is associated with the HLR
MS MSC HLR AUC
EIR (Equipment Identity Register) EIR is the Mobile Equipment Database which has a series of IMEIs
MSC asks the Mobile to send its IMEI
MSC then checks the validity of IMEI with the EIR
All IMEIs are stored in EIR with relevant classifications
EIRMSC
What is Mobile Number Portability
Mobile Number Portability [ MNP ] Number portability enables a
subscriber to switch between services, locations, or operators while retaining the original mobile number, without compromising on quality, reliability, services and operational convenience.
A subscriber can choose to keep his number functional even if he switches services of a Mobile Service Provider
Thus his/her old number would still be functional on the new network
Advantages of MNP Subscriber’s benefit Convenience of customer to personalize
the same number across the Operators, Locations and Services. (No age for your number.)
Better QOS, more features and services, better tariff plans for customers.
No cost incurred to notify the new contact details to the others ( friends, family, business…..)
Operator ’s benefit Healthy competition and an opportunity to explore more services/features.
Operator with best QOS will gain the subscribers.
Introduction of innovative service.
Advantages of MNP
MNP - Some facts
Out of several types of number portability DoT has recommended Mobile Number Portability (MNP) for all mobile service operators
Two central clearing houses for MNP database covering North-West zone (Syniverse) and South-East zone (Telecordia)
These CCH will download the MNP database in operators NPDB on daily basis
MNP will be restricted only for intra circle operators
MNP will be allowed between CDMA and GSM operators
ACQ (All Call Query) direct routing method to implement MNP
MNP Terminologies related to network
Originating
Network
Originating
Network
Donor Network
Donor Network
Recipient Network
Recipient Network
NPDB
Originating Network : Network of the calling party
Donor Network : Previous subscription of Called party
Recipient Network : Present subscription of Called party
NPDB : Number Portability Data Base (maintains portability and provides routing instructions)
Commonly used terms Non Ported Number – Mobile Numbers belonging
to UNINOR. These numbers will be defined in the NPDB with HLR (PC & SSN) information. Will be defined in the Range DN Table of the NPDB.
Ported In Number – Number ported into UNINOR from another network. These numbers will be defined in the NPDB with HLR (PC & SSN) information. Will be defined in the Single DN Table of the NPDB.
Ported Out Number – Number Ported out to another network from UNINOR. These numbers will be defined in the NPDB with RN information. Will be defined in the Single DN Table of the NPDB.
(ACQ) All call query- Direct routing method
Whenever the call is originated, the Originating n/w will query its NPDB
NPDB will acknowledge the query by adding a prefix (LRN) to the B MSISDN if the B MSISDN is ported out.
Based on the prefix (LRN) the Originating n/w will route the call to the recipient n/w without involving the Donor network.
Originating
Network
Donor
Network
Recipient
Network
ORIG NW
NPDBL
RN
+ B
-MS
ISD
N
B-M
SIS
DN
ACQ is called as direct routing as
donor network will not be included
during entire call flow.
LRN + B-MSISDN