UMTS and Beyond

Prof. Hamid AghvamiCentre for Telecommunications Research - King’s College London

Wireless Multimedia Communications Ltd

Mobile System Generations

First Generation (1G) mobile systems were designed to offer a single service, i.e., speech.

Second Generation (2G) mobile systems were also designed primarily to offer speech with a limited capability to offer data at low rates.

Third Generation (3G) mobile systems are expected to offer high-quality multi-media services and operate in different environments.

3G systems are referred to as Universal Mobile Telecommunications System (UMTS) in Europe and International Mobile Telecommunications 2000 (IMT2000) worldwide.

UMTS

“UMTS will be a mobile communications system that can offer significant user benefits including high-quality wireless multimedia services to a convergent network of fixed, cellular and satellite components.It will deliver information directly to users and provide them with access to new and innovative services and applications.It will offer mobile personalised communications to the mass market regardless of location, network and terminal used”.

UMTS Forum 1997

UMTS Main Requirements (3 Ms)

Multi-media

Multi-environment

Multi-operator Virtual operators

VideoConference

(High quality)

VideoConference

(Low quality)

TelephoneConference

Telephone

VoiceMail

ElectronicMail FAX

ElectronicPublishing

ElectronicNewspaper

ISDNKaraoke

VideoCatalogshopping

Database AccessRemote medical

service(Medical image) Video on

demand -Sports -News -Movies

Mobile TV

MobileRadio

Image

DataVoice

Multicast

Multi Point

AsymmetricSymmetric

Point to Point

Broadcast

　

2M

384K

64K

32K

16K

9.6K

2.4K

1.2K

News

Weatherforecast

Traffic information

Sports information

LeisureInformation

Mobile Multimedia

WWW

e-mail

ftp

IPtelephony

etc

InformationDistribution

Services

InternetAccess

pager

Mobile Multimedia Services

Global

Suburban

Macro-Cell

Urban

Micro-Cell In- Building

Pico-Cell

Home-Cell

Different Environments for UMTS

Europe has decided to adopt an evolutionary approach for the UMTS core network based on migration from the GSM/GPRS infrastructure.

For the actual air interface, a revolutionary approach has been chosen. That is a new radio air interface for UMTS Terrestrial Radio Access (UTRA).

There is another parallel activity concerning the UMTS air interface using an evolutionary approach (an intermediate approach).

First phase of UMTS

Evolution approach based on GSM InfrastructureEvolution Approach

New

Radio Access (UTRAN)

NSS

And

GSN’s

PSTN

N-ISDN

B-ISDN

IP-based

Networks

Radio Access GSM Infrastructure

Public Network

Dual-mode

Dual-mode

Evolved

GSM

Radio Access (GERAN)

In this approach the GSM air interface has evolved within GSM phase 2+ to support higher rate data services. The most important developments in this approach are:

1. General Packet Radio Services (GPRS )2. High Speed Circuit Switched Data (HSCSD )3. Enhanced Data Rates for GSM Evolution (EDGE )

It is referred to GSM/EDGE Radio Access Network (GERAN)

Evolutionary approach for the GSM Air Interface

SMSC/VLR

GMSC

PSTN

HLR

PDN Internet

GGSN

SGSN

RNC

Ci rc

uit S

wi tc

hed

(GSM

)

Pack

et S

witc

hed

(GPR

S)

UTR

AN

Iu,psIu,cs

Gs

C

Gn

Gr

Gc

UMTS – Phase I

D

RNC

Node B Node B Node B Node B

Iu,cs

Iu,ps

….…

…….…..

….…

Applications& Services

Legacy mobile signalling network

Other PLMN

MultimediaIP networks

GGSN

PSTN/legacy/external

SGSN

SGSN

HSS(HLR)

GGSN

EIR

SGW

MRF

CSCF

MGCF

MGW

Simplified architecture for the support of IP-based multimedia services in 3GPP release 5

Signalling interfaceSignalling and data transfer interface

Gn

Gp

Mh

Cx

Mm

Gi

Mg

Mc

Gi

Gi

Mr

Gc

Ms

Gn

GiGr

Gf

TE MT GERAN

TE MT UTRAN

Iu-PS

Uu

UmR

R

New Functional Entities for the All IP Architecture

• Call State Control Function (CSCF) executes the call control. It is based on the IETF Session Initiation Protocol (SIP).

• Media GateWay (MGW) provides an inter-connection from GGSN to legacy circuit-switched networks such as PSTN.

• Media Gateway Control Function (MGCF) controls the MGW.

• Media Resource Function (MRF) performs multiparty call and multimedia conferencing functions.

• Signalling GateWay (SGW) performs signalling conversion to/from legacy mobile signalling network.

• Home Subscriber Server (HSS) is an evolved HLR.

4G Concept

Towards 4GTowards 4GUser centric,

user controlled servicesand

context-aware applications

What does “user controlled services” mean?What does “user controlled services” mean?

“ The user has freedom and flexibility to select any desired service with reasonable QoS and affordable price, anytime, anywhere using any device in a secure manner”

4G Concept

What does “context-aware applications” mean?What does “context-aware applications” mean?

“ A context-aware application means the behaviour of the application adapts itself to user context changes. User context includes: -user profile and preferences. -user device and access network capabilities. -user environment and mobility. ”

4G Concept

Technologies

ChallengesChallenges• Convergence/integration/inter-working of all

existing and emerging fixed and mobile (wired and wireless) networks including broadcast

• Simple to select and easy to use desired services

• Universal and low cost terminals

IP Technology

Agent Technology

Reconfigurable Technology

• Inter-working Concept

• Integration Concept

Network Level Concepts

Interworking/Integration

• For the design of next generation wireless networks two different approaches are currently being considered. They are:

- Interworking with next generation Internet (tight coupling)- Integration within next generation Internet (very tight coupling)

• In the first approach, the access network and the core network use different IP protocols and mechanisms and only the core network is considered as a sub-network of the Internet.

• In the second approach, both the core and access networks use common IP based protocols and mechanisms and the access network is considered as a sub-network of the Internet.

The Internet

IP backbone

Billing VHESignalling Gateway

WAP Accounting

UMTS

Broadcast Networks (DAB, DVB-T)

Satellite FES

GSM / GPRS

Context-aware informationCentre

IP-based micro-mobility Wireless

LANs

ISPSIP Proxy Server

Inter-Working

General architecture of the IP-based IMT network platform

Applications

AP1 AP2 AP3 APn

Middleware

IP-based transport NW

Location Accounting/billing Media conversion Distribution

Basic network management sub-layer

RRM MM C/SM Security QoS

Service support sub-layer

IP IPIP

IPRadio

Radio RadioIP IP

IP

ISDN/PSTN

Internet

Integration

Global coverage

National coverage

Local area coverageWireless LANs

DAB and DVB-T, DVB-S

2G, 3G and 4G Cellular

Personal area coverage

Hierarchical coverage layers for 4G

Satellite

Regional coverage

Wireless PANs

Vertical Handover

Horizontal Handover

IP-based backbone

The complexity of the problem: user prospective

From a user prospective

Multiple　Heterogeneous　network　operatorspart　of

　Multiple　user　environments　accessed　using　

Multiple　heterogeneous　devices　owned　by

　heterogeneous　users

LaptopPDA

UMTS DVB WLAN

From a network prospective

Multiple　Heterogeneous　network　operators

providing　Multiple　services

through　multiple　access　networks

tousers　with　heterogeneous　devices

The complexity of the problem: network prospective

Service

Access technology

Operators

Bluetooth GPRS WLAN

Downward Vertical Handover1 2

(i.e. GPRS WLAN)

Upward Vertical Handover2 3

(i.e. WLAN Bluetooth)

1

2

3

Operator D

Operator C

Operator B

Operator A

Service A

Service B

Service C

A Heterogeneous Network Architecture

UTRAN WLAN 4G RAN

PAN

Wireless Access Network

Core Network Future Internet

Intra-Cell PAN Ad-hoc Network PAN PAN

PAN

Inter-working between two radio access networks Open coupling

Inter-working between two radio access networks Loose coupling

Inter-working between two radio access networks Tight coupling

Inter-working between two radio access networks Very tight coupling

Inter-working examples - cachingHSS

SGSN

IP network

CSCF

MPEG-2 real time encoder

Packetiser IP packet

inserter

ATM/SDH

leased network

Transport Multiplexer

MPEG-2 real time encoder

Stream server

Gateway/IP

Encapsulator

Carousal Generator

Location Profile

Response(3)

Query(2)

Cache Server

Request mp3's / movie

(1)

Petrol station

Retrieve content

Content transfer

(5)

Content Storage(HTML,Clips,

mp3's, games)

DVB-Tregional

multiplexer

DVB-Tregional

multiplexer

local content

Response(4)

Satellite

Content transfer

(6)WLAN

Content　DeliveryNotification

Content:　video　clip(15MB)Service:　Music　ClipsCompany:　MTV

Please　select　delivery　options　　　　Send　to　PDA　(5　eur)　–15min　　　　Send　to　office　PC　(10　eur)　–7min　　　　Send　to　STB　(20　eur)-2min

Delivery options

Network provides device delivery optionsincluding cost and delivery times

User selects desired destination

Slide:Slide:3030-40-40

Inter-working examples user centric

Load balancing i.e. Using DVB to multicast or broadcast to large number of users

Handovers i.e. Users in train moving outside the coverage of a network

Slide:Slide:3131-40-40

Inter-working examples – network centric

Network SelectionNetwork Selection

Most Appropriate Network Selection Criteria

• User Context

• Service Type

• Available Resources

- Data rate- QoS

- Environment (When and Where)- Mobility- User preferences

Convergence

Convergence of Cellular Mobile Networks and WLANsBenefitsFor cellular mobile operators Higher bandwidths. Lower cost of networks and equipment. The use of licence-exempt spectrum. Higher capacity and QoS enhancement. Higher revenue.For users Access to broadband multimedia services with lower cost and where mostly needed (e.g. in Central Business Districts and Business Customer Premises). Inter-network roaming.

Convergence

Convergence of Mobile Communications and BroadcastingDriversFrom broadcaster point of view

Introducing interactivity to their unidirectional point-to-multipoint broadcasting systems. That is, a broadband downlink based on DAB/DVB-T and a narrowband uplink based on 2G/3G cellular systems.

From the cellular mobile operator point of view

Providing a complementary broadband downlink in vehicular environments to support IP-based multi-media traffic which is inherently asymmetrical.

Convergence

Benefits

Broadcasters will benefit from the use of cellular mobile systems to adapt the content of their multi-media services more rapidly in response to the feedback from customers.

Cellular operators will benefit from offering their customers a range of new broadband multi-media services in vehicular environments.

Users will benefit from faster access to a range of broadband multi- media services with reasonable QoS and lower cost.

Steve Deering - Cisco : Fifty-first IETF; London, England, August 5-10, 2001

IP Layer ModelIP Layer Model

Additional IP Functions Mobility Management Quality of Service AAA

IP Sec Ad-Hoc Routing etc.

Native IP Functions: Routing Addressing Packet Formatting and Handling

Lower Layers

Higher Layers

IP Network Layer

IP Convergence Layer

Data Interface

Error Control Buffer Management QoS Support Segmentation/Reassembly Header Compression Multicast Support

Control Interface

Configuration Management Address Management QoS Control Handover Control Idle Mode Support Security Management

IP Layer Model for WLANsIP Layer Model for WLANs

IP Layer Model

The functionalities and structure of the IP layer model are not sufficient and/or efficient to achieve the requirements of future inter-worked or integrated networks.

No fundamental changes have been made in the design of IPV6.

The question is:

“ Are some radical changes needed to the IP layer model in order to offer better solutions to the convergence issue?” If yes, what are the consequences and implications?

“ An agent is a software component (object) that is situated within an execution environment (e.g. computers) and acts autonomously on behalf of a user or process and has specific goal.”

Agent Definition

2G, 3GWLAN

…

AP

AP: Agent Platform

AP AP

AP

Service Centre

Agent Technology

• Mandatory features– Reactive: senses changes in the environment and reacts in accordance.– Autonomous: has control over its own actions– Goal-driven: is pro-active

• Optional features– Collaborative: communicates/negotiates with other agents–Mobile: travels from one host to another– Learning: adapts in accordance with previous experience– Believable: appears believable to the end-user.

Mobile vs. Static Agents

Client Server

Client Server

request

respond

requestrespond

“Software components that can migrate under their own control from host to host in a network or between networks”

Mobile Agents

• Mobile agents have already been used for network monitoring and service delivery including education at a distance.• In an ever-increasing world of service providers and service packages, a user demands a simple approach to the selection of the desired service and its delivery mechanism in real-time with least effort. This can be achieved through the use of mobile agents.• The use of mobile agents can also overcome the constraints imposed on applications by the limited processing power and speed of mobile terminals.

An open question:An open question:

Static or mobile agents for wireless networks?What are the pros and cons?

Agent TechnologyAgent Technology

Re-configurable Technology

What does Reconfiguration mean?

“Reconfiguration refers to the software re-definition and/or adaptation of every element within each layer of the communication chain.”

BasebandProcessing

UserData

A/D Converter

D/A Converter

RF Front End

Re-configurable Technology

Benefits• Users

• Operators

• Manufacturers

- Select network depending on service requirements and cost.- Connect to any network – Worldwide roaming.-Access to new services.

- Respond to variations in traffic demand (load balancing).- Incorporate service enhancements and improvements.- Correction of software bugs and upgrade of terminals.- Rapid development of new personalised and customised services

- Single platform for all markets.- Increased flexible and efficient production.

Re-configuration Procedures

ReconfigurationTrigger

Mode Identification

Mode Negotiation

Software Download

Mode Switch Decision

ModeMonitoring

ReconfigureTerminal

Initiated by network operator or user

Download software modules that are required

for the target mode

What networks are available?

What is the most suitable network (based on QoS, user preferences etc.)?

Decision on preferred mode

Re-configurable Technology

CHALLENGES

• Regulatory and Standardisation issues.

• Business models.

• User preference profiles.

• Inter-system handover mechanisms and criteria.

• Software download mechanisms.

• Flexible spectrum allocation and sharing between operators.

• Enabling Technologies (RF and antenna elements, ADC/DAC etc.)

Agent Technology

Conclusion

4GVision

IP TechnologyReconfigurable Technology