Migration towards IP standards in GSM Mobile Networks

Rajkrishna Srinivasan780915A355

2G1330, Wireless and Mobile Network Architecture3rd June 2004Royal Institute of Technologyrsr@kth.se

Structure

• Why this topic?

• GSM Introduction

• The life cycle

• IP in GSM

• IP in GPRS

• IP in 3G

• The Future

Why this topic?

• Technology suffers due to proprietary standards

• IP - Open Technology

• Telephony through IP picking up

• Best Effort Service in Carrier Grade System?

GSM Introduction - 1

• CEPT - Conférence Européenne des Postes et Télécommunications

• SMG – ETSI

• GSM – Global System for Mobile Communication

• A Success Story – 190 + countries

GSM Introduction - 2

HLRAUC VLR

MSC

BSC

BTS

MS

BSC

BTS

MS

BSS

A Interface

SS

Life Cycle

• Need to evolve

• New methods to make money

• Data Traffic

• Existing spectrum getting congested

GSM Architecture

MS MSC BSS

TDMA/FDMA TDMA/FDMA

LAPDm LAPDm

RR

MM

CM

RR

MTP

BSSAP SCCP

BSSAP SCCP

MTP 1

2

3/M

Radio Interface A-Interface

MM

CM

IP in GSM

• No provision for IP in this architecture

• Ericsson Trials of “GSM on Net”1

• But still no “real support” for DATA – only HSCSD

• Since IP not used -> Problems of interoperability

1 -http://www.theregister.co.uk/1998/12/23/ericsson_plans_merger_of_wireless/

GPRS

• First attempt to address problem of handling data

• Consists of GSNs (Support Nodes)

• Pay for data usage – always connected!

• Only an interim solution

IP in GPRS

Relay

Network

Service

GTP-

Application

IP

SNDCP

LLC

RLC

MAC

GSM RF

SNDCP

LLC

BSSGP

L1bis

RLC

MAC

GSM RF

BSSGP

L1bis

Relay

L2

L1

IP

L2

L1

IP

GTP-U

IP

Um Gb Gn Gi MS BSS SGSN GGSN

Network

Service

UDP

UDP

3G

• What is 3GPP

• Significance of Release 5

• WCDMA UMTS

• SIP and IP for Multimedia

3GPP Architecture

• Radio Network Controller

• Node B

• Home Subscriber Server

• IP Multimedia Subsystem

Why IMS

• Release 4 of UMTS problems

• VoIP market growth

• Session Initiation Protocol -> Call Control Protocol

• New content, killer apps, multimedia

Why SIP in IMS

• Change in internet model

• Client Server – HTTP, FTP etc

• Now it’s Peer to Peer

• Here SIP has five roles in Establishing, maintaining and terminating communications: User Location, User Availability, User Capability, Call Setup and Call Handling

3GPP Architecture

Open Service Access

• Who is going to make use of all this technology?

• How to boost ARPU?

• Parley group

• Parley OSA -> Common Application Programming Interface (API)

OSA Architecture

framework User Location

HLR CSE WGWWPP

Servers

Service capability server(s)

Interfaceclass

OSA APIOpen Service Access

discovery

Application

Applicationserver

OSA internal API

Challenges for IP

• IP designed for traditional internet - delay is OK!

• Lower layers shielded – Preventive strategy for critical applications

• Notorious radio links

The Future

• 3GPP – Europe and Japan

• 3GPP2 – America and Korea

• IP in 3GPP and 3GPP2

Conclusion

• All IP alternative – Huge Bandwidth Available

• More revenues – ARPU vs. OpEx/CapEx

• More enriched services

• 4G – The “all IP” system

Thank You

• Questions and Comments

• Mail address: rsr@kth.se

• Mobile: +46 736959977