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An Open Service Architecture withLocation Aware Calls and Services

Lill Kristiansen, Prof. Dr. Scient

Dept. of Telematics, NTNU, Norwaywww.item.ntnu.no/~lillk

www.pats.no (lab-information)

lill_kristiansen@hotmail.com

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Outline of the talk

Trends in evolution Layering, separation and towards ’all-IP’

Some mobility definitions User mobility, service mobility, terminal mobility,… Virtual home environment

Brief overview of UMTS IMS system (release 5,..)

Brief overview of Parlay / UMTS OSA API for ’value added services’

A framework to discuss technical solutions to mobility Illustrations of GSM/Camel and IMS/OSA in this

framework Illustrations of possible ’middleman’ arrangements using

OSA, to decrease the ’operator centric view’

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The scope of this talk:

We are mostly based on the current and upcoming ETSI/3GPP definitions (GSM, IMS and OSA)

We look into combinations of ’telephony’ and location based services

We consider that each operator: Has some hardware and software controlled by himself

Hence has control over the non-functional requirements in this way

We do not consider ’mobile code’ in general But we may foresee upgrades of software from vendor to

operator, or from operator’s management system to operator’s switches (call servers and service nodes

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Evolution:

Several activities going on From CS (Circuit switched)

to PS (Packet switched) From monolitic systems (GSM and PSTN)

to layered systems with one common core systemwith several access technologies

QoS and realtime aspects GSM (2G CS):

supports ’voice ’interactive conversation with 1 medium) UMTS (3G first releases): CS multimedia (H.324M) supports multimedia telephony

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System topology

Today

• Separate Networks • Separate Users • Separate Services

Tomorrow

• Separate Accesses• Same Core network• Same User on different accesses• Same Services

Dat

a/IP

Net

wo

rks

Dat

a/IP

Net

wo

rks

PL

MN

PL

MN

PS

TN

/ISD

NP

ST

N/IS

DN

CA

TV

CA

TV

Separate Services

Separate users

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UMTS from release 5 on: IMS: IP Multimedia Subsystem

Same Core network

Same User on different accesses

Same Services

I can use WLAN, ADSL, LAN, UTRAN (GPRS) etc. as accesses in ONE system

I can have several devices and move between them

Servers

Users

Backbone Network

AccessAccess

Communication Control

Content Content

Access

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General types of mobility

Mobility between several technologies (e.g. with the same handheld device having several (radio) access modes).

User mobility across different devices.

Mobility in a network (i.e. inside one technology). Terminal mobility in GSM network

Either inside one operator domain (/one country) Or ‘roaming’ (to a foreign contry/operator domain)

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General mobility definitions

Personal mobility enables users to use services that are personalized with their preferences and identity ubiquitously, independently of both physical location and specific equipment. … (From TINA-C in the mid-90’ties)

Service mobility (of a particular service) is defined as the ability for a user to obtain that particular service independently of user and terminal mobility. (Ericsson contribution to ETSI Tiphon 1999)

Virtual Home Environment (VHE) is defined as a concept for Personal Service Environment (PSE) portability across network boundaries and between terminals. The concept of VHE is such that users are consistently presented with the same personalized …. (3GPP TS 23.127)

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2G GSM

Internet

Mobile

WAPe.g. email

MMoIP(1)e.g. MMS

MMoIP(3)IMS/’telephony’

MMoIP(4) e.g. P2T

3+G from rel.5 UTRAN

3G first releasesUTRAN

2,5G ERAN

”4-G” WLAN

MMoIP(2)e.g. steaming (and H.324M)

Evolution (modified from Kanter)

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QoS and realtime aspects

The CS part: GSM (2G CS):

supports ’voice telephony’i.e.: ’interactive conversation with one medium’

UMTS (3G first releases CS): (H.324M) supports ’multimedia telephonyi.e. ’ ’interactive conversation with multi media’

The ’data’ part: GSM supports CS-data:

not used for ’conversation’ (too much delay) GSM/GPRS (2G, 2,5G) supports SMS, and MMS:

MMoIP(1): QoS BE: Best Effort (not requiring real time support) GPRS with streaming MMoIP(2)

From realease 5: All-IP common voice/data Full QoS enabling MMoIP(3) (VoIP and MMoIP in)

IMS: Interactive Conversational Services over IP, using SIP

Via WLAN: P2T/PoC (Push to Talk /over Cellular) varying QoS(delays and walkie-talkie-like)

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UMTS IMS architecture HSS: Home

SubscriberServicesHLR-like

CSCF: ’Call Server’Call/SessionControl Function

P-CSCF Proxy-

I-CSCF Interrogating-

S-CSCF Serving-

xGSN GPRS-noder

Visited B

Home A

Visited A

AB

Home B

GGSN

SGSN

Radio Access Network

GGSN

SGSN

Radio Access Network

P-CSCF

I-CSCF

HSSHSS

S-CSCFI-CSCF S-CSCF

P-CSCF

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UMTS IMS: basic call flow

Non-GPRS accessNetworks (e.g. WLAN)comes in release 6

P-SCSFP-SCSFVisited B

Home A

Visited A

AB

Home B

GGSN

SGSN

Radio Access Network

P-CSCF

I-CSCF

HSSHSS

S-CSCFI-CSCF S-CSCF

WLAN

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Virtual Home Environment (3GPP):

VHE enables end users to bring with them their personal service environment whilst roaming between networks, and also being independent of terminal used

PSE Personal Service Environment:

describes how the user wishes to manage and interact with her communication services. It is a combination of a list of subscribed to services, service preferences and terminal interface preferences. PSE also encompasses the user management of multiple subscriptions, e.g. business and private, multiple terminal types and location preferences.

The PSE is defined in terms of one or more User Profiles.

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3GPP OSA architecture

Allows application to use underlying network resources

Allows combinations: Location capabilities (from GSM/UMTS and WLAN)

Radionor Cordis Radioeye allows detailed location in WLAN

SMS/MMS capabilities Call Control capabilities

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PLMN(GSM/UMTS CS)

PSTN/ISDN (CS) IP Multi-Media (PS)

Capability Server(s)(including interface classes)

Application

Application Server

Application

Application Server

Application

Application Server

OSA Interface providing open API’s to Applications

Capability Server(s)(including interface classes)

Capability Server(s)(including interface classes)

Parlay and UMTS Open Service Access;Migration and Convergence

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Today (2000 and 2004) on PC: type in your location into web-pagemanuallyTomorrow:fixed LAN,and WLAN access into same core system

Parlay/OSA for data-services

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Bank services

Location services

Leisure

News

For data services (From Ericsson 2000) Avoid typing, get location automatic e.g. into WAP page (or into SMS content)

Today in Oslo, Norway(2004):Call taxi, application fetches your location:nearest taxi comes (combinations: call, location, applic.data!)

Further issues: mobility between operators, countries and companies for this taxi service

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A Framework to analyse the relations between home and visited in 2G and 3G

This figure assumes no mobile code i.e. more specifically:

Each box is: hardware, software run by one operator

(We may note that mobility in both 2G and planned versions of 3G all assumes no mobile code.)

Home-NW

End-point

V/access-NW

End-point

S)

C)

Home-NW

V/access-NW

A Side (originating) <-- --> B side (terminating)

Home-NW

End-pointEnd-point

V/access-NWV/access-NW

End-pointEnd-point

S)

C)

S)

C)

Home-NW

V/access-NW

A Side (originating) <-- --> B side (terminating)

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Framework applied to 2G with OSA

NOTE: There is a typo in the paper, this is the right version of Figure 3, showing Camel

S)

C)MSC+VLR MSCCC CC

WAP WAPGW

IN/Camel

HLR

SCS

OSAAS2 S2)

HLR

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3G IMS system in this reference model

This is previous IMS-slide, now slightly re-arranged

P-SCP-SC

Visited B

Home AHome B

Visited A

GGSNRadio A NW

P-CSI-CS

HSSHSS

S-CS I-CS S-CS

WLAN

SCIMSCIM

AS

SGSN

ASAS

P-SCP-SC

Visited B

Home AHome B

Visited A

GGSNRadio A NW

P-CSI-CS

HSSHSS

S-CS I-CS S-CS

WLAN

SCIMSCIM

AS

SGSN

ASAS

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OSA revisited:with several service providers involved

AS S)

C)

OSA

SCIM

AS2

Appl.SCS

S2)

AS3 S3)

OSA

AS4Sub.

2G or 3G network underneath OSAHLR/HSS

AS S)

C)

OSA

SCIM

AS2

Appl.SCS

S2)

AS3 S3)

OSA

AS4Sub.

2G or 3G network underneath OSAHLR/HSS

This may be the (national) regulator

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Advantages with this new solution

Less ’operator centric’ Does not require the 3rd party service provider to have a

business relation with the operator The regulator acts as ’neutral middleman’:

assuring equal access for all service providers Single point of contact for the enduser Easier for the enduser to enforce a good privacy policy

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Network centric =/= operator centric

AS3 is a network based solution, but totally independent from the network operator domain

A personal web-page might also act as a network based solution See Jan Egil Kristiansen Our addresses and phones,

http://heima.olivant.fo/~styrheim/kontakt.en.html The enduser himself controls the user mobility, and (in non-

realtime) informs his contacts about the ’current terminal/SIM card)

Allows the enduser to buy local GSM-cards, instead of the often more expence network operator centric solution with ’roaming’ That is often very expensive, and subject to little competition

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Summing up the reference figure

Allows us to discuss different business models between home and visited networks Fits in with 2G & Camel &OSA

Shows some major drawback with Camel Due to call server (MSC in visited network)

Also fits in with 3+G (IMS) & OSA Nice to use when discussing the advantages of having S-

CSCF in home network vs. (the now gone option of S-SCSF in visited network)

Useful when discussing the fully mobile case of ’call nearest taxi’

Fits in also with private initiatives not described in the 3GPP standards

Further issues: Mobile code is not covered