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UMTSUMTS NETWORK ARCHITECTURENETWORK ARCHITECTUREUMTSUMTS NETWORK ARCHITECTURENETWORK ARCHITECTURE

External

Networks

CS Domain

PS Domain

Entities common

to the CS & PS Domain

GSM BSS

UTRANUE

RANRadio Access Network

CNCore Network


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PSTN

X.25

ISDN

IP

IWF/

TC

GMSC

GGSN

MSC /VLR

SGSN

HLR AUCEIR

TRAU

B

S

C

BTS

R

N

C

BTS

Node B(n x BTS)

R

N

C

Node B(n x BTS)

Node B(n x BTS)

UE

CS Domain

PSDomain

GSM BSS

UTRAN




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11--Core Network DomainCore Network Domain

Structure of the CN.Structure of the CN.


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Circuit Switching DomainCircuit Switching Domain

MSC FunctionMSC FunctionSignaling switching and call routing to or from MS.

Charging.Control of connected RNCs.

One MSC controls more than one RNC.

GMSC FunctionGMSC FunctionAccess to PSTN.

Provides the gateway functionality/Interface

to other networks.

MSC/VLR


Circuit Switching DomainCircuit Switching DomainVLR FunctionVLR Function

Associated with MSC

Subscriber Management in MSC area.

Authentication co-ordination.

VLR Data.VLR Data.A temp data base that holding the following information

Services available and restrictions.

Temp subscriber information.TMSI; LAI; triples.etc.

The VLR hold these data for the subscriber included in the

MSC area only.


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Supercharger

Large database

Periodic Auditing

Dynamic subscription data deletation



TCTranscoding

&

IWFInterWorking Function

TCTranscoding

BlaBlaBlaBlaBla

Bla

CN function in UMTS:part of MSC or standalone

Conversion of Speech Data (CN RAN):using AMR speech codec

CN: 64 kbit/s (ISDN)

RAN: 4.75 12.2 kbit/s (AMR)

AMR: Adaptive MultiRate

4.75 12.2 kbit/s 64 kbit/s (ISDN)

UTRAN CN



VLR

IWF/

TC

TRAU

B

S

C

R

N

C

MSC

Iu(CS)

AB

RANRadio Access

Network

FGs

E

C


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TCTranscoding

&

IWFInterWorking Function

VLR

IWF/

TC

TRAU

BS

C

R

N

C

MSC

Iu(CS)

AB

RANRadio Access

Network

FGs

E

C

Interworking: TDM ATM all classical CN-Interfaces (A-G):TDM based (E1/T1 PCM30/PCM24)

Iu(CS): ATM based

Interworking: TDM ATM all classical CN-Interfaces (A-G):TDM based (E1/T1 PCM30/PCM24)

Iu(CS): ATM based

IWFIWF





ATM Asynchronous Transfer Mode

cell-based switching technique

ATM exposes properties from both circuit switched and small packet switched

networking

ATM is a core protocol used over the SONET/SDH backbone

ATM uses a connection-oriented model and establishes a virtual circuit between

two endpoints before the actual data exchange begins

5 48

Cell = 53 Byte

if small: high header-to-data overhead

if large: low utilization for small messages

Special switches and routers which is faster can be used as we use fixed length


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Register and Service domainRegister and Service domain

HLR FunctionHLR Function

The HLR is a centralized (unique) network database that storesand manages all mobile subscriptions.

IMSI, MSISDN

Services subscribed

Service restrictions (e.g. roaming restrictions)

Parameters for additional services

Authentication data

Temporary information

Current VLR address

Current MSC address

MSRN (if user outside PLMN)

Authentication

- It is a processor system that performs the authentication function

AUC

RAND

Database

IMSI,Ki

A8A3

RAND SRES Kc

Triplet

KiIMSI

Triplet

Request for Triplet

from HLR,VLR




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A3

Ki

A3

KiRAND

VL

R

SRES

=?

SRES

SRES

HLR/AUCM

S

Yes

NoAuthentication Refused"

message

Continueciphering

IMSI



Authentication Center AUC

For a try to take 1usec it needs

10790283070806014188970529.15499 year to get K



A Key of 128 bit is used

One way

Function

K

RANDX


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Authentication Vector AV

RANDRandom Number

128 bit

XRESExpected Response

F2

CKCipher Key

F4

IKIntegrity Key

F3

AUTNAuthentication Token

F1+F5

USIM VLR / SGSN

Authentication Request

[RAND(i), AUTN(i)]

Authentication Response

[RES(i)]User Authentication:

CompareXRES(i) & RES(i)

generate RES(i) =f2(RAND(i),K)

AUTN(i) forNetwork Authentication

randomly generated,

i.e. non-predictable

Used for data

encryptionUsed for

integrity check

consisting of 3 parts

Used for networkauthentication

Used for user

authentication

Receiver

Control Data

Transmitter

provides security against:

unauthorised modification of control data

change of data origin

Control DataEncrypted

check sumControl Data

Encrypted

check sum

IK dependentcheck sum generator

F9

IK

check sum

GeneratorF9

Expected

check sum

Encrypted

check sum

IK

Data Integrity Check

Basic Principle

Equal?


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USSD USSD Unstructured Supplementary ServiceUnstructured Supplementary Service Data GatewayData Gateway

USSD is generally associated with real-timeor instant messaging type phone services.

SMSC is not present in the processing

path).

A USSD Gateway routes USSD messages

from the signaling network to service

applications and back

Media gateway serverMedia gateway server..

This translates media traffic between different

types of network.

Media GatewayMedia Gateway


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Other nodes for the register domain.Other nodes for the register domain.EIR: equipment identity register.

IN: intelligent network.SMSC: short message service center.

SGSN


Packet switching domainPacket switching domainSGSN FunctionSGSN Function

Forwards incoming and outgoing IP packets addressed

to/from a mobile station that is attached within the SGSN

service area.

Provides packet routing and transfer to and from the

SGSN service area.

Ciphering and authentication

Mobility management

Output of billing data.


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Packet switching domainPacket switching domain

GGSN FunctionGGSN Function

The interface towards the external IPpacket networks.

Acts as a router

Address mapping

Tunneling

Output of billing data.

22. Access Network Domain. Access Network Domain


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22--Acess NetworkAcess Network

RNC functionRNC function

Function of the RNC.Function of the RNC.Control several node Bs/ interface with the core network (MSC/SGSN).

Radio resources management.Admission (access) and congestion control.

Handover and power control (outer loop).

Ciphering/deciphering.


Node B functionNode B functionFunction of the Node B.Function of the Node B.Contains the RF equipment that provide

the radio link in the air interface.

More intelligent than BTS.

Perform spreading/dispreading, channel

coding, also responsible of a part of the

power control (inner loop).

Records and passes to the RNC the Signal

strength measurements

Mapping of Transport channels into

physical channels


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Node B functionNode B function

Quite widely referred to as the driver receiver (DRX). Basically does transmission

and reception of signals

Amplifies the signal from DRX for transmission through antenna; may be integrated

with DRX.

Combines feeds from several DRXs so that they could be sent out through a single

antenna.

For separating sending and receiving signals to/from antenna.

This is also considered a part of the BTS.

Collects working status alarms of various units in the BTS and extends them to

(O&M)

Frequency hopping, signal DSP, etc..




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Pico Cell

Cells Types

Micro & Macro

Cells

Repeater Cells

Outdoor IndoorStreet LevelIndoor

COW Green FieldRoof Top

MonopolePolesStup tower Tower



Outdoor repeater:Outdoor repeater:




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Indoor repeater:Indoor repeater:



Green filed:Green filed:

Antennas

Equipment

Antennas

Equipment




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Roof top:Roof top:

Antennas



COW (Cell on Wheels):COW (Cell on Wheels):

Used as a temporary solution to provide

Coverage or Capacity for certain duration

(Events).




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Street level:Street level:



Indoor:Indoor:




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33-- User Equipment domainUser Equipment domain

Function of the User Equipment domainFunction of the User Equipment domain ..

The end user node; that provide the services/application to the users.The new generation of UMTS phones will combine the advantages of

wireless communication with the demand for multimedia applications

Consists of.

User Terminal.

UMTS Subscriber Identity Module (USIM)

UE


User TerminalUser TerminalMultimode user equipmentMultimode user equipment


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User TerminalUser TerminalUSIM function.USIM function.

Stores user addresses

IMSI,TIMSI, rooming, etc

Authentication and encryption features

subscribers secret authentication key (Ki and K)

Security Algorithm & Keys (for Authentication, Ciphering,..).

Personalization

SIM stores user profile (subscribed services)

SMS, short numbers, etc

Protection codes PIN ,PUK

Vodafone CoverageVodafone Coverage


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MobinilMobinil 33G CoverageG Coverage

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