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Overview of GSM
An Introduction to the
GSM network
Copyright1996NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996
NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996NorthernTelecom
Copyright1996NorthernTelecom
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Overview of GSM
Course objectives:
give a basic understanding on GSM in general, focusing
especially on the HLR (Home Location Register); learn about what services a GSM network provides;
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Overview of GSM
Introduction to the course: a bit of history
Part 1: Overview of GSM Network
Part 2: Introduction to CCS7
Part 3: Services provided by GSM network
Part 4: Signalling and Call routing
Part 5: HLR & HLR-PS
Conclusion: GSMs future
Course content
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Overview of GSM
What is GSM?
initially Groupe Spciale Mobile
became Global System for Mobile communication
GSM is the most widely used mobiletelecommunication standardin the world.
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Overview of GSM - Introduction to GSM
GSM? Global System for Mobile communicationsGSM is the Worlds leading wireless Communication standard.
Usage: Approximately 70 Million Customers, deployed in 109Countries (1998Q1)
It is estimated that no later than in 2005, the number of mobile phonesubscribers should overtake that of fixed-line telephone subscribers. Bycontinuing its dramatic expansion, the penetration of mobile telephoneswill, between 1997 and 2002, increase from 20% to 50% in NorthAmerica and from 13% to 40% in Western Europe, thus reaching 10% forthe world as a whole compared to 3.4% at the end of 1997. (Pascal
Debon, Nortel, May 1998)
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Overview of GSM - Introduction to GSM
Melanie Reynolds, June 1998:
GSM has passed the 100 million user mark, exceeding the most
optimistic industry predictions. More than five million new GSM users are
being added every month, with users in over 120 countries. Ericsson, the
Swedish telecoms company, forecasts that there will be more than 450million users by the end of 2003.
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Overview of GSM - GSM History
Early 80s: development of the first cellular systemsanalog system;
no compatibility between networks (=> no possible roaming);
demand increased too fast for systems capacity
obvious need for a common system
1982: Groupe Spcial Mobile formed to work on a newcommon technical standard
1986: successful field tests conducted in France
-> 22 European countries signed a MOU (Memorandum of Understanding) andcommitted to fulfilling the GSM recommendations
-> commercial service began in July 1991
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Overview of GSM - GSM History
1988: GSM group transferred to newly created ETSI(European Telecommunications Standards Institute)
1992 - today:development phase, from main capital cities + airport to urban then
rural areas;
enhancement and definition of new services;
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Evolution of cellular telephone system
First Generation Systems (FDMA)Analogue
multiple specifications (AMPS, NMT, TACS, RADIOCOM, CT1)
No Roaming: systems incompatible with each others
Second Generation Systems (TDMA, CDMA)
DigitalGSM standards (900, 1800, 1900)
other standards: DECT, CT2, CDMA, PHS
roaming
secure
Third Generation Systems (W-CDMA, W-TDMA)UMTS, FPLMTS, IMT-2000 (Satellite System)
UPT - Universal Personal Telecommunications
Seamless coverage in sparsely and densely populated areas
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Overview of GSM - Part 1
Copyright1996NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996
NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996NorthernTelecom
Copyright1996NorthernTelecom
Part 1:
Overview of GSM Network
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Overview of GSM
Introduction of new concepts
GSM networks architecture
Mobile Station and possible identifications Base Station Subsystem (BSS)
Network and Switching Subsystem (NSS)
Operation and Maintenance Center (OMC)
GPRS
Part 1: Overview of GSM Network
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Introduction to telecommunication network
PSTN: Public Switched Telecommunication Network(example: BT land network);
PLMN: Public Land Mobile Network (example: Vodaphone
network); Radio side of GSM(BSS)
Switching side of GSM(NSS)
Operation side of GSM(OSS)
A few concepts...
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Visited PLMN
NSS
BSS
Home PLMN BSS
NSS
Introduction to telecommunication network
National PSTN
Copyright1996NorthernTelecom
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Copyright1996NorthernTele
com
Copyright1996NorthernTelecom
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GSM Networks architecture
BTS
BS
C
BSC
BTS
BTS
DMS-MSC
VLR
NES
BTS
BSC
BSC
BTS
BT
S
DMS-MSC
VLR
NES
BSC
BSC
BTS
DMS-HLR
AUC
NES
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Mobile Station and Identifications
Mobile Station (MS)=
Mobile phone +SIM CardA mobile phone needs a SIM card to be usable.
Mobile Phone: handset
SIM card: Subscriber Identity Module (containsidentification information)
The SIM card is usually the size of a credit card andcontains an electronic chip. This chip holds information thatidentify uniquely the phone user (referred to as asubscriber).
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Mobile Station and Identifications
IMSI:International Mobile Subscriber IdentityNumber that identifies the subscriber for the internal business of GSM.This number is unique to the subscriber and is no longer than 15 digits(defined in E212 standards).
MCC: Mobile Country Code (3 digits)
MNC: Mobile Network Code (2 or 3 digits)
MSIN: Mobile Subscriber Identification Number
The IMSI contains information about the network it belongs to and its
unique identity in this network.
However, a mobile phone user does not need to know his IMSI!
THIS IS NOT THE SUBSCRIBERS PHONE NUMBER!
MCC MNC MSIN
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Mobile Station and Identifications
MSISDN: Mobile Station ISDN NumberDialled number when a call is placed to a GSM network. The MSISDN isalso unique to the subscriber and no longer than 15 digits (defined inE164 standards).
CC: Country Code (example: 44 for UK)
NDC: National Destination Code (example: 0467 for Vodaphone)
SN: Subscriber Number
The MSISDN contains enough information for the network to route the
call.A mobile phone user should always know his MSISDN .
THIS IS THE SUBSCRIBERS PHONE NUMBER!
There may be more than 1 MSISDN per subscriber.
CC NDC SN
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Security
Calls are encrypted when they leave thehandset;
identity information is always encrypted
when sent on the network;
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Base Station Subsystem
Cellsize can be up to 35km diameterdetermined by environment and capacity requirements
Cells are arranged in clusters to maximisefrequency reuseTypical arrangements are 7 and 4
Hotspots can be fixed with microcells,
picocells and sectoring
Cell is smallest BSS element
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Base Station Subsystem
BTS: Base Transceiver StationBTS is antenna plus associated hardware ~ 1
cellConverts compressed radio signal to conventional
telephone signal
BTS can be very large or very small (picocellfor metro stations, airports, etc..)
Many BTS, comprising a Location Area (LA)are connected to the Base Station Controller
(BSC)
Generally 1 BTS per cell
BTS
B
TS
BTS
BTS
BTS
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Base Station Subsystem
BSC: Base Station ControllerManages a group of BTSs in a location area
Manages handover between BTSs
Interfaces between BTS and NSS (BSC
connected to 1 or more BTS, and an MSC);Allocates and releases radio channels;
BTS
BSC
BSC
B
TS
BTS
BTS
BTS
R di H d
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Radio Handover
MS is in constant contact with the nearestfew BTSs
Both BTS and handset monitor strength ofradio signal
When signal is stronger in another BTS (orcell) an inter-BTS handover occursManaged by BSC (intra-BSC handover)
When handover between BTSs crosses aLA, a inter-BSC handover occursManaged by MSC (intra MSC handover)
BTS
BSC
BSC
B
TS
BTS
NSS
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NSS
NSS: Network & Switching Subsystem:+ Link between GSM subscriber and other network;
+ switching function + database administration
MSC: Mobile Switching Center;
HLR: Home Location Register;VLR: Visitors Location Register;
IWF: Inter Working Function;
SMS-SC: Short Message Service - Service Center;
N t k d S it hi S b t
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Network and Switching Subsystem
MSC: Mobile Switching CenterISDN switchserves various Base Station Subsystem
main functions are:
MS call set-up, routing, control and signalling;
digit translation;
billing data capture, formatting and teleprocessing;
authentication and ciphering;
inter-MSC handover
short message and supplementary services support;
Also contains service logic function, to implement services;
GMSC (Gateway MSC): MSC that acts as an interface between amobile network and a land network;
Net ork and S itching S bs stem
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Network and Switching Subsystem
HLR: Home Location Registerdatabase: home base of information;holds permanent subscriber data
identification and numbering information (IMSI, MSISDN,);
service information (services provisioned for each subscriber, )
contains dynamic infolocation information
roaming information (roaming restrictions,)
AuC: Authentication Centerdatabase: permanent subscriber data + security information
provides the keys for maintaining security of subscribers identity
safeguards to protect network operator and subscribers against fraud
Nortel: collocated with the HLR
Network and Switching Subsystem
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Network and Switching Subsystem
VLR: Visitor Location Registerdatabase: local copy of informationconcerning subscribers
located in the VLR zone
assigns temporary numbers to subscribers (such asTMSI)
standalone function, but collocated with MSC
EIR: Equipment Identification Registerdatabase: tracks valid & invalid MSsby storing their
International Mobile Equipment Identity (IMEI)
holds 3 lists of IMEI:
Black list: MSs barred from using network (stolen, )White list: MSs allowed to use the network without restrictions
Grey list: MSs suspected of being faulty, delinquent payments...
Network and Switching Subsystem
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Network and Switching Subsystem
SMS-SC: SMS Service Centeracts as a store-and-forward center for short messages
IWF: Inter Working Functioninter working function for data
GPRS (General Packet Radio Service):GSM-defined mobile packet data service (as opposed to the currentcircuit data services). This enables bursty, discontinous dataapplications such as WWW browsing and Road Traffic Information.GPRS allows users to hold several address types, i.e. IP or X.25.
SGSN: Serving GPRS Support NodeGGSN: Gateway GPRS Support Node
Operation & maintenance Subsystem
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Operation & maintenance Subsystem
The OSS supports the management and maintenanceactivities of the GSM network.
In 98Q3, the following applications are available:
OMC-S: Operation and Maintenance Center- Switching
HLR OMCs
HLR-PS: HLR Provisioning Server (interface to subscribers data)HLR FM PM: HLR Fault Management & Performance Management (interface to
TMN network)
MSC OMCsMSC FM PM: MSC Fault Management & Performance Management
CIS: Call Intercept System
GBMD: GSM Billing Mediation DeviceASES/ISES: Automatic/Interactive Service Evaluation System
Exercises
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Exercises
Who am I?I am part of the BSS that transcodes the radio signal into electrical
signal. I am a _______.
I temporary hold the information about the mobile phones located in
my zone. I am a ______.I am the permanent database that contains IMSI, MSISDN, services
I am a ______.
I take care of the switching part of the GSM network. I am a ______.I must say that I am capable of routing calls from the GSM network tothe land network. I am called a ____________.
I am the card slipped in a mobile phone. I am a __________.
Exercises
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Exercises
What is the missing word?The location of a subscriber is stored by the _______.
The 2 elements that provide the interface between BSS and NSS are:
on the BSS side, the _____;
on the NSS side, the _____;The MSISDN is nothing more than the ___________________.
Exercises
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Exercises
On a GSM network, some of the elements are:HLR, VLR, MSC, EIR, BTS, MS, BSC, AUC, GMSC, SMS-SC
Try to order these elements from the most common to the rarest one:
Most common
Most uncommon
Overview of GSM - Part 2
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Overview of GSM Part 2
Copyright1996NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996
NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996NorthernTelecom
Copyright1996NorthernTelecom
Part 2:
Introduction to CCS7
Introduction to CCS7
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Introduction to CCS7
Concept of signalling v. voice
Introduction to CCS7
MTP & SCCP UP and BSSAP
TCAP & MAP
GSM interfaces
Part 2: Introduction to CCS7CCS7: Common Channel Signalling number 7
Concept of signalling v. voice
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Concept of signalling v. voice
2 types of signal pass among components:voice and data: the call itself, reason for a user to own a phone;
signalling: sets of messages/signals used to pass information from oneanother, query another element, control, set up, monitor and take
down a call; Every element in a GSM network deals with signalling. This is
not the case for voice and data.
Concept of signalling v. voice
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p g g
DMS-HLR
AUC
NES
DMS-MSCVLR
NES
DMS-MSC
VLR
NES
BTS
BSC
BS
C
BTS
BTS
BTS
BSC
BSC
BTS
BTS
Voice & dataSignalling
Introduction to CCS7
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CAS: Common Associated Signalling (disappearing)
Voice and signalling are mixedon the same channel. Every channelof the trunk is used for both voice and signalling:
CCS: Common Channel SignallingOne (or more) channel is reserved for signallinginformation traffic.
Voice and signalling follow 2 different paths
signal-lingVoice
signal-ling
signal-ling
Voice trunks
Signalling
Exercises
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What is the difference between CAS and CCS?
Can you think of any advantage of CCS v. CAS?
What is the minimum number of signalling channels and
voice channels that the HLR needs?
Introduction to CCS7
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CCS7: Common Channel Signalling number 7
version of CCS designed for digital networks;
enables CCS over dedicated data links;uses packet switching
defined as a protocol: this ensures that reliable information is sentin the multi-vendor network that GSM networks are;
structured in layers, each layer being responible for a specific setof functions;
Introduction to CCS7
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MessageTransferPart
ISDN/BT/CT...UserPart
MobileApplicationPart
Transaction
Application PartCapabilities
Base Station
System ApplicationPart
BSSMAPDTAP
Signalling Connection Control Part
Network: Signalling Network Layer
Link: Signalling Link Layer
Physical: Signalling Data Link Layer1. Physical
2. Link
3. Network
4. Transport
5. Session
6.Presentation
7. Application
OSI reference model
MTP and SCCP
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MTP: Message Transfer PartProvides means for reliable transport and delivery of user part
signalling information across the network,
Ability to react to system & network failure that affect reliability of
transport & delivery of the user part.
Responsible for point to point communications within nationalnetwork.
SCCP: Signalling Connection Control Part
transfers the message from the origination to the destination signalling
subsystem;
enables the tracking of application status at nodes;
deals with message routing.
UP and BSSAP
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UP: User Part
builds on services of MTP to provide connection-oriented signalling forsetting-up, monitoring, clearing down the voice trunks of GSM CCS7 calls.
may be ISDN User Part (ISUP), British Telecom User Part (BTUP), ChinaTelecom User Part (CTUP)
BSSAP: Base Station Subsystem Application Part
handles signalling involving mobile stations, base stations subsystem and
DMS-MSC.
TCAP and MAP
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TCAP: Transaction Capability Application Part
takes care of maintaining the connection once the connection is up, by
the use of timers, transaction identities, ...
MAP:Mobile Application Part
highest layer;
contains the information itself;
Exercises
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Draw the CCS7 layers for each of the followingcomponents:
MSC HLR
GSM interfaces (for reference)
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VLR VLR
HLR
EIR
BSCDMS-MSC
BSC
SCP
SSP
VoiceSignalling
G interface
C-in
terface
E-int. A-int.
PSTNNetworkInterface
MSC/GSMC
BTS
A-inter.
BTS
Copyright1996NorthernTelecom
Overview of GSM - Part 3
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Copyright1996NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996
NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996NorthernTelecom
Copyright1996NorthernTelecom
Part 3:
Services provided by GSM Network
Services provided by GSM Network
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Basic Services
Supplementary Services
Proprietary services
Advanced Services
Security
Part 3: Services provided by GSM Network
Basic Services
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Basic Services (BS):Services that provide calling facility. They all have a MSISDN.
A subscriber may have more than 1BS provisioned.
BSs are grouped together by types called Basic Service Groups.
Two kinds of basic services:
tele-services (end-to-end services). Examples are:telephony
auxtelephony
fax
short message group
bearer-services. Examples are:CDA group(Circuit Duplex Asynchronous)
CDS group(Circuit Duplex Asynchronous)
Supplementary Services
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Concept: add values, complements basic services
Supplementary Services (SS):IMSI based SS: applies to all basic services, not to individual basic
service groupscall identification: CLIP, CLIR, COLP, COLR
call hold, multi-party
...Basic Group based SS: applies to all basic service from selected basic
service groupcall forwarding: CFU, CFB, CFNRY, CFNRC
Call forwarding services can be Provisioned, Registeredand/orActivated.
call barring: BAIC, BAOC, BOIC, BICROAM, BOICEXHC
call waiting: CW
...
Proprietary Services
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Proprietary Services:
Specific services (not defined in specs.) that Nortel has decided toimplement for its customers
ALS: Alternate Line Service
associates two Mobile Subscriber ISDN numbers (MSISDNs) with a subscriber(IMSI) for telephony calls.
The two lines have separate Supplementary Service profiles and are billedseparately.
EXT: Extension servicesadvanced call forwarding feature (sequential or parallel multiple call forwarding)
HOTBILLallows call records to be directed to a different billing stream for immediate
retrieval.
Advanced Services
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Advanced Services:IN Based Services
Virtual Private Network (VPNs),
Number portability,
Home zones,
Freephone, pre-paid,etc
Data ServicesHigh Speed Circuit Switched Data (HSCSD)
GPRS
Intelligent network
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Principle: separation of service logic from call processing
Conventional GSM:
IN based:
Call Processing
Service Logic
Call Processing
Service Logic
G-MSC MSC/VLR
Service Logic
Call ProcessingCall Processing
IN Architecture
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PSTN GSM IN
GMSC
SSP
MSC/VLR
SSP
MSC/VLR
SSP
HLR SMS
SCE
SCP
SSP
SMS: Service Management System
SCE: Service Creation System (initializes IN network)
SCP: Service Center Point (interacts with remote nodes)
SSP: Service Switching Point (implements service logic)
GPRS
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General Packet Radio Service (GPRS)
Overlay NSS packet data networksame radio and HLR
support for X.25 and IP addressing
Gives up to 150kbits/s to mobile
available 99Q3
DMS-HLR
BSC
BSC
BT
S
GSM NSS
GPRS NSS
Exercises
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Can you think of incompatible services?
Services depending on other services?
Security
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Authenticationused as a means of validating subscribers access to network;
happens on an update location message sequence;
the AUC holds the Ki (16 bytes) data for each subscriber;
sets of RAND (16 bytes) and SRES (4 bytes) supplied by AUC;
Authentication sets normally used once only
Ciphering Key (Kc)allocated at authentication time
Kc is 8 bytes long
Kc used to encrypt calls
Security - Authentication
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MSC/VLR
A3Ki
HLR/AUC
RAND
SRESRAND & SRES
A3KiCopyright1
996NorthernTelecom
Security - Ciphering Key
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A8
Ki
HLR/AUC
RAND
MSC/VLR
A8 A5Ki KcCopyright1996
NorthernTelecom
BSC
A5
RAND & Kc
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Copyright1996NorthernTelecom
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Copyright 1996
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Copyright 1996NorthernTelecom
Copyright1996NorthernTelecom
Part 4:
Signalling and Call Routing
Signalling and Call Routing
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Location update
Originating call
Terminating call
Hand-over
These are summaries/overviews of the message sequences that take
place. It generally concentrates on the HLR aspects.
Part 4: Signalling and Call Routing
Location update
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DMS-HLR
DMS-MSC
VLR
DMS-MSC
VLR
1- UL
2- ISD
3- ISD Ack4- UL Ack
3-CL
Ack
Between new visited VLR and HLR:1- Update Location2- Insert Subscribers Data3- Insert Subscribers Data Ack4- Update Location Ack
Between HLR and previous VLR (if applicable):2- Cancel Location3- Cancel Location Ack
When MS first detected by VLR...
Originating calls
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DMS-HLR
DMS-GMSC
DMS-MSC
VLR
The HLR does not need to be consulted as:- the information about the subscriber isstored locally (VLR)
- the MSC can route the call using thedialled number!
When MS makes a call...
Copyright
1996NorthernTelecom
Terminating calls
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DMS-HLR
DMS-GMSC
DMS-MSC
VLR
2- PRN
3- PRN Ack
4-SRIAck
Between MSC and HLR:1- Send Routing Information
Between HLR and VLR:2- Provide Roaming Number3- Provide Roaming Number Ack
Between HLR and MSC
4- Send Routing Information Ack
When a call needs to be routed to the MS...
Hand-over
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VLR
NES
VLR
NES
BSC
BSS
BSC
BSS
Copyright
1996
Northern
Telecom
2- Perform Handover
5- HandOver Number
Exercises
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What is the role of the PRN sequence?
What happens if there is a call to route to the MS but...
CFU is active?
the location is unknown?
Exercises
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What happens if the MS wants to make a call before the UL-ISDsequence has taken place?
During which kind of Hand-over is a UL-ISD sequence generated?
To establish a call from a MS to a MS, what is involved on each end(that we have seen in the previous slides)?
What happens if the HLR is dead?
Overview of GSM - Part 5
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Copyright1996NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996
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Copyright1996NorthernTelecom
Part 5:
HLR & HLR-PS
HLR & OMC-HLR
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Position in the GSM network
HLRFunctions of the HLR
GSM interfaces
internal structure
HLR-PSFunctions of the HLR-PS
platform
Part 5: HLR & HLR-PS
Position in the GSM network
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IP
MSCHLR
SMS-CVLR
SCP(CSE)
HLR
HLRPS
FMPM
?
Functions of the HLR
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Database:information stored in database and accessed through tables control
and command interface:table: logical storage
database: physical storage
permanent info (IMSI, MSISDN, services);dynamic info (subscribers location,roaming information,);
allows or forbids roaming of MS in PLMN;
Functions of the HLR
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updates VLR with subscriber information; gives MSC information for calls requests towards MS:
by providing location of MS and roaming number (see SRI-PRN);
by providing call-forwarded-to number if call forward service active;
holds AuC function (authentication);
GSM interfaces
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C-interface: HLR-MSC - for call/short message routing
from/to normal MSC or G-MSC:SendRoutingInfo: to route call to MS
from/to Short Message Service Center:
SendRoutingInfoForSM: to route short message to MSAlertServiceCenter: to inform service center of MS ready for short
message
ReportSMDeliveryStatus:
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GSM interfaces
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Call routing preparation:
ProvideRoamingNumber: prepares VLR to receive a call;NoteMSPresent/ReadyForSM: informs HLR that MS can receive a short
message;
Service changes requested from handset:CISS operations (register/erase, activate/deactivate, interrogate
Supplementary Service): register, erase, activate, deactivate,interrogate a supplementary service on the HLR;
MSs observationActivateTracemode: triggers events tracing function at the VLR;
DeactivateTracemode: disables events tracing at the VLR ;
ProvideSubscriberInformation: requests from the HLR informationabout MS (such status of location information);
HLR Internal Structure
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Nodal perspective:
2 Sides for robustness: active side and inactiveside (swact: switch activity)
System either in sync or out of sync
CM1
CPU
Memory Mngt Unit
Input/Output
Memory
CM0
MS1
ClockCard
DS512Card
MS0
PM (LIU7,)
PM: Peripheral module
CM: Computational moduleMS: Message Switch
ONP
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ONP: One Night ProcessThis is the upgrade process of the HLRverify validity of data/functionality on existing load
remove redundancy of the HLR (HLR out of sync)
upgrade inactive side
transfer all database information (subscribers info, )
swact activity (inactive side becomes active)
verify validity of data/functionality on new load
put HLR back in sync (point of no return)
HLR Stand-by
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active DMS-HLR
AUC
NES
DMS-MSC
VLR
NES
DMS-MSC
VLR
NES
Voice & data
Signalling
DMS-HLR in Stand-by
AUC
NES
Mated-pair HLR Operations
Normal Operation:
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IMSI 123 Acting LondonIMSI 124 Acting London
IMSI 223 Standby Glasgow
IMSI 224 Standby Glasgow
HLR 1 (London) - Standby active
IMSI 123 Standby LondonIMSI 124 Standby London
IMSI 223 Acting Glasgow
IMSI 224 Acting Glasgow
HLR 2 (Glasgow) - Standby active
Normal Operation:
Updates 123
Updates 223
IMSI 123 Acting London
IMSI 124 Acting London
IMSI 223 Acting Glasgow
IMSI 224 Acting Glasgow
HLR 1 (London)Standby off (standalone)
IMSI 123 Standby London
IMSI 124 Standby London
IMSI 223 Standby Glasgow
IMSI 224 Standby Glasgow
HLR 2 (Glasgow)Standby off (out-of-service)
Disaster in Glasgow:
Exercises
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In which context would a reset happen? How wouldit be handled?
What are the CISS messages for?
Why are there 2 sides the switch? How does it work?
Exercises
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In the case of HLRs working in standby, what are
the problem regarding the upgrade?
Functions of the HLR-PS
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HLR-PS: HLR Provisioning Server
Modification of subscribers data:immediate changes: Administration Center (AdC)
creation/deletion of blank subscribers: SIM Personalization System(SPS)
bulk provisioning of subscriber: Bulk Subscribers Provisioning (BSP)
Virtual HLR feature (transparent segmentation of the HLR)
Fault and Network management (not always collocated withnodes);
Fully configurable product to adapt to customers needs;
HLR-PS Provisioning Gateway
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DMS-HLR2DMS-HLR1
HLR-PS1 HLR-PS2
BSPAdCSPS
HLR-PS to DMS-HLR linksends subscriber data
AdC, SPS and BSP provisioning
send data to either HLR-PS
Inter HLR-PS link re-routestransactions to the correct HLR-PS
MAP based links - responsible for re-routing Network side messages tocorrect DMS-HLR
HLR-PS Platforms
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Provisioning OMC-S
HLR
NES
TCP/IP NFS
RS232 FTP
X25
TCP/IP
VT100
Platforms
HPSDM
SDM/FT
Exercises
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Using the HLR-PS, which functions can I use toprovision a subscriber with CFNRY?
What is the role of the provisioning gateway?
Overview of GSM - to conclude...
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Copyright1996NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996
NorthernTelecom
Copyright1996NorthernTelecom
Copyright 1996NorthernTelecom
Copyright1996NorthernTelecom
To conclude...
GSM s future
GSM s future
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Different customers have different needs for new servicesThey too need more services to sell new phones!
Still a lot to do to take over the normal land telephonesystem;
Increasing demand on the data side;
Increasing bandwidth requirements (especially to thehandset)
fixed mobile convergence
Universal Mobile Telecommunications System (UMTS)
IN (Camel)
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Customized Applications for Mobile Enhanced Logic (CAMEL)Provide space for new servicescomplex customized call forwarding features
home zone
Virtual Private Network (VPNs)
Number portability
Moves the Service Logic function of the MSC to IN nodes.
UMTS
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UMTS = Universal Mobile Telecommunications SystemETSI's project to develop a "third-generation" wireless standard
Mobile communication anywhere, anytime
UMTS will build on the global success of GSM
Radio-agreed combination of W-CDMA and W-TDMA