7_introduction to gprs

8/9/2019 7_Introduction to GPRS

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GSM900

DCS1800

Introduction to GPRS


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At the end of the module the participant will beable to:

Describe the relationship between GPRS andGSM

Describe the difference between packetswitching and circuitswitching and the meaning of these to data

services

Describe some benefits of GPRS

to end-users

to operators

List some business reasons for GPRS

List some possible GPRS applications that wouldgenerate revenue

Objectives


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Current trends in mobile markets:Current trends in mobile markets:

Mobile traffic is growing faster than fixed traffic

More than 400 million GSM mobile phones Prediction: In 10 years # mobiles > # of PSTN lines

Data traffic is growing faster than voice traffic More than 150 million Internet users worldwide growing

Many fixed network operators carry more data traffic than voice

Mobile traffic growth + Data traffic growth = GPRS

growth!

In many countries, majority of people have a mobilephone

Mobile operators have to stay competitive

Setting competitive tariffs

Offering value-added services

Background


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eTForecasts

0

100

200

300

400

500

600

700

800

900

1989 1990 1995 1999 2000 2002 2005

inmill i

on

Internet Growth Rates


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low cost PCs email Intranet harmonisation growing content in the Web

business to businesselectronic commerce

business to consumerelectronic commerce

etc.

today

broadband connections (last mile) mobile commerce Web enabled mobile phones Web based radio and TV etc.

and tomorrow

Driving Forces for the Internet Growth


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

Network databases Base Station Subsystem (BSS)

Base Transceiver Station (BTS)

Base Station Controller (BSC)

Transcoder and Rate Adaptation Unit (TRAU)

Network Management Subsystem (NMS) Operations and Maintenance Centre (OMC)

Mobile Station (MS) Mobile Equipment (ME)

Subscriber Identity Module (SIM)

Components of a GSM network


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BSS

BSS

NSS

PSTN/ISDN

MS

NMS

Network SwitchingSubsystem

Switching Mobility Management

(incl. authentication) Connection

Management Charging

Base Station Subsystem Radio Resource

Management(incl. Transcoding)

Radio Link Management

Network ManagementSystem

Fault Management Configuration

Management Performance

GSM Public Land Mobile Network


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BSC

BTS

BTS

TRAU

BSC

BTS

BTS

TRAU

BSS

BSS

NSS

MSC/VLR GMSC

HLREIR AC

PSTN/ISDN

MS

NMS

A

A

Um

GSM Public Land Mobile Network


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Mobile Stations

Base Station Subsystem Network Management System

BaseTransceiverStations

Base StationController

TranscoderSubmultiplexer

Digital CrossConnect

A-Interface Air Interface X.25 Interface Abis Interface

IN Service Control PointShort MessageService Centre

Voicemail

Mobile Switching Centre/Visitor Location Register

Home Location Register/Authentication Centre/Equipment IdentityRegister

Network Subsystem

PSTN/ISDN

CommunicationsServer

DataCommunication

Network

Database Server

Workstations

NetworkPlanningSystem

NetworkMeasurementSystem

TCP/IP

Data CommunicationsServer

GSM network architecture


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Tasks of NMS: Fault management Configuration management Performance management

BSC

HLR/AC/EIR

TCSM

MSC/VLR

UnixWorkstations

Database andCommunications

Servers

NMS/2000

GSM Network

Router

DataCommunicationsNetwork (DCN)

Network Management Subsystem


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Duplex Transmission

Frequency Division Duplex Time Division Duplex

frequency

tim

e

frequency

tim

e

Uplin

k

Uplink

Uplink

UplinkDow

nlin

k

Downlink

Downlink

Downlink

Radio Interface Concepts


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Circuit switched

Packet switched

Circuit switched vs. Packet switched


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Telepho

nenetwork

s

Packet switched

Data

networ

ks End-to-end connection (call)

establishment needed

Dedicated resources (e.g. PCM-tsl) forone user are reserved during callestablishment

Only 30 - 40% of resources areeffectively used for speech transfer

Speech is transferred in real time

Speech does not accept delays

Errors in transmission are not so criticalfor speech

Charging is usually based on time

No connection needed

Resources are shared betweendifferent user sessions, notdedicated

Resources are requested ondemand, more efficient use

Packets are not sent in real time buffering and delay

Error correction and detectionpossible

Charging is usually based on

volume number of packets

Circuit switched


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Telepho

ne

networks

Packet switched

Data

networ

ksPhysical circuit

PCM-tsl

(CONS) End-to-end connection (call)

establishment needed Dedicated resources (e.g. PCM-

tsl) for one user are reservedduring call establishment

Only 30 - 40% of resources are

effectively used for speechtransfer

Speech is transferred in realtime

Speech does not accept delays Errors in transmission are not

so critical for speech Charging is usually based on

time

Virtual circuit (VC) NoVC

X.25 IP(CONS)

(CLNS)

No connection needed Resources are shared between

different user sessions, notdedicated Resources are requested on

demand, more efficient use Packets are not sent in real

time buffering and delay Error correction and detection

possible Charging is usually based on

Circuit switched


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content

conte

nt Networkserver

Subscribers Point of View

I l Vi f GPRS N k


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Subscriber

Radio

NetworkCCB

Inter-Operator GPRS

Backbone Network

GPRS

Roaming

Voice

Traditional GSM

Operator

Infrastructure

Billing Systems

Integration ???

IT Infrastructure

GGSN

IP Access

Routers

Firewalls

Addressing

Authentication

Security

LIG

Billing

CG

NMS

DNSHelp Desk

Internet Access

Corporate Access

NMS

External Services,

WAP and others...

BSC

SGSN

MSC/VLR HLR

Border

Gateway

Internal

DNS

Implementors View of GPRS Network

GSM D t S i Sh t i


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Users point of view 9.6 kbps transmission rate ceiling max. 160 characters for SMS circuit switched services expensive for

bursty applications

Radio interface problems may lead todata losses

Data integrity may not be givenvia the Internet

call establishment duration

Operators point of view

inefficient use of radioresources

displeased customers

GSM Data Services Shortcomings

Wh t i GPRS?


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Technology which permits mobile data communicationusing packet switching techniques

GSM allows circuit switched (CS) data transfer

Data transfer on a dedicated channel (connection oriented)

Connection setup procedure needed as in modem

Subscriber charged according to time of connection

TS is held for duration of connection - waste of resources

GPRS designed as an extension to digital cellular

networks Connectionless packet switched (PS) data service

Standardised by ETSI

Radio resources shared between CS and PS data

New terminals are required

What is GPRS?

O i th B ttl k U


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Increased data transmission ratesvia new Coding Schemes

CS-19.05kbps

CS-213.4kbps

CS-315.6kbps

CS-421.4kbps

Bundling of up to8 physical channels

Net transmission rate up to171.2 kbps

data rates onon physical channel(one timeslot)

All physical channel

must be located onthe same TRX

Overcoming the Bottleneck Um


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capacity on demand

ynamic allocation ofadio resources toircuit & packet switched

Multiplexingseveral users sharing onephysical channel

Asymmetricallocation of uplink anddownlink resources


Who are the GPRS users?


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Business users Corporate intranet access Mobile ISP for small enterprises

Industrialapplications

Private users Demand forvalue-addedservices

Messaging Internet

Who are the GPRS users?

Private users


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Personal messaging: E-mail,

pictures, voice

Mobile

Browsing

All-in-onecommunicator

MMS terminal formobile Multimedia

Messaging Service

WAP terminals for using WAP-enabled services

Regular web browsingpossible withall-in-one communicator

Small group of advanced users,

with a laptop for personal useNormal customer requirements

on ISP:e-mail, web, news, chat

Mobile operator's ISP

infrastructurerovides standard Internet

Laptop

Private users

Business users: Corporate intranet access


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Corporate networks are primarilyusing IP

Business users usually have alaptop

Access to existing IP-basedapplications on the corporate

intranet: e-mail, intranet andInternet browsing, database lookupand entry, etc.

Resilient background transfer: Nomore "LOST CARRIER" during filedownload

The remote office becomes areality; remain networked whereveryou are

Business users: Corporate intranet access

Operator Type 1


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Mobile Access Operator Operator acts as transparent bit-

pipe

Limited differentiationpossibilities: price, bit rate,availability, etc.

The ISPs control theend-customers through actualservices and content access

Small risks for the operator:low cost, small revenueopportunity

Internet

WWWWWW

ISP orcontentprovider

Operator Type 1

Operator Type 2


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Full-Service Operator

Contentproviders

Corporations

Internet

Multimedia

ServiceCenter

SMS,SMS,

HSCSD,HSCSD,

GPRS,GPRS,

3rd generation3rd generation

Operator adds value by offeringservices with value to the end-

user

Opportunity to differentiate:

customer loyalty

new customers andrevenue streams

brand recognition

Higher risk, new competenciesrequired

Operator Type 2

Key learning points (1/3)


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GPRS uses a packet-based technique which will enhanceGSM data services significantly, especially for bursty

Internet/intranet traffic. Some application examples:

bus, train, airline information

locating restaurants and entertainment venues

weather information

security information

lottery

e-commerce

banking

e-mail

web browsing




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The main advantages of GPRS for users:

Instant access to data as if connected to an office LAN

Charging based on amount of data transferred (not the timeconnected)

Higher transmission speeds

The main advantages for operators:

Fast network roll-out with minimum investment

Excess voice capacity used for GPRS data

Smooth path to 3G services




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In circuit switching each time a connection is requiredbetween two points, a link between the two points is

established and the needed resources are reserved for theuse of that single call for the complete duration of the call.

In packet switching, the data to be transferred is dividedup into packets, which are then sent through the networkand re-assembled at the receiving end.



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Review Questions to

Introduction to GPRS

Review


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1. Give an example of a CS network and identify threecharacteristics. :

PSTN, classical mobile telephony networks

a) Connection orientated

b) Optimised for speech transmission (real-time

and low arrival jitter)

c) No error correction

Review

Review


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Internet (IP), X.25, Frame Relay

a) User data organised in packets

b) Connectionless (e.g IP) and connection

oriented (e.g. X.25) network solutions areavailable

c) Non-real time data transfer

d) Statistical multiplexing

2. Give an example of a packet switched network and identifythree characteristics.

Review

Review


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3. Name two benefits of GPRS.

a) Increased radio interface efficiency

b) Charging based on volume is possible

c) Higher data rates are possible in

comparison to GSM

d) Coverage holes do not automatically result in

data losses for the end user

e) Smooth transition to 3G

f) Always-connected access to data networks

g) New data services can be applied

h) Fast network roll-out is possible

Review

Review


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4. Give three examples of services that could be carried overGPRS.

a) WAP

b) e-mail

c) e-commerced) industrial applications telemetry

e) corporate access

f) gaming

Review

7_introduction to gprs

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