Contribución al Desarrollo de Soluciones Contribución al Desarrollo de Soluciones Para la Integración de Métodos de Para la Integración de Métodos de Establecimiento de Sesión en Redes 4GEstablecimiento de Sesión en Redes 4G

((ContributionContribution toto DesigningDesigning SuitableSuitableSessionSession SetupSetup SolutionsSolutions in 4G in 4G NetworksNetworks))

Autor: D. Antonio Cuevas CasadoAutor: D. Antonio Cuevas Casado

Director: Dr. José Ignacio Moreno NovellaDirector: Dr. José Ignacio Moreno Novella

1717thth JulyJuly 20062006

TESIS DOCTORALTESIS DOCTORAL

Departamento de Ingeniería Telemática

Doctorado en Tecnologías de las Comunicaciones

Tesis Doctoral 1

Outlook

� Design suitable session setup solutions in 4G networks

1. Introduction, Objectives

2. State of the Art

3. Integrating Sessions: Requirements

4. 4G Proposed Architecture and Session Setup Support

5. Signalling

6. Validation

7. Conclusions

Tesis Doctoral 2

Introduction, Context

� Migration of the circuit switched networks towards an IP world is happening:

�

� Vinton Cerf: “no sense to keep two separate networks”

� Reasons for such an important change

� Increase revenue due to ease of building new services over the Internet and their acceptance by the users

� Reduce costs to operators: manage only one network

Tesis Doctoral 3

Introduction, Context

� For us, 4G is an Internet like network with extra features, many, such as mobility, already present in cellular networks

� A 4G network is not a 3G “All-IP” network (3G network with an IP overlay)

� Lots of research efforts in 4G networks

Tesis Doctoral 4

Introduction, challenges and open points

� In 4G, terminals are IP hosts. Risks for the operators to become bit pipes

� Migration can not be avoided, avoid its bad consequences for the operators

� Convergence in business models?? still not clear. Thus…

� One topic to still handle in 4G networks is session setup.

� The problems come from the fact that a session is composed of subsessions (transport, application) handled by different business entities

Tesis Doctoral 5

Introduction, objectives

� Design Session Setup solutions integrating application and network layer aspects and services in 4G networks

� Focus on orchestration between the different entities, systems, modules

� But keeping Internet paradigm: transport & service separation

� Position the network operator in the core of the business value chain

� Analyze and compare different proposals & scenarios

Tesis Doctoral 6

Outlook

� State of the Art

� See what is profitable, research opportunities matching our objectives

� Integrating Sessions: Requirements

� Sessions are split, advantages and requirements to integrate them

� 4G Proposed Architecture and Session Setup Support

� Design needed aspects, session setup techniques in different scenarios

� Signaling

� Closes the solution, important for understanding simulations

� Validation

� Methods, rules to design 4G networks

� Conclusions

Tesis Doctoral 7

Outlook

� Introduction

� State of the Art

� See what is profitable, research opportunities matching our objectives

� Session Setup Techniques

� IMS

� 4G

� Integrating Sessions: Requirements

� 4G Proposed Architecture and Session Setup Support

� Signaling

� Validation

� Conclusions

Tesis Doctoral 8

IETF session setup solutions

� RSVP: offer + answer. To setup transport sessions. Few parameters, simple model

� In the IntServ framework

� In the “application” layer:

� SIP & SDP (+SDPng) very adequate, plus mechanisms (RFCs) to coordinate SIP and QoS setup

� Lacks cost sharing parameters

Tesis Doctoral 9

IMS

ISC

Interface

SIP/SDP

IPv6

IP external networks

HSS

UTRAN

SGSN GGSN

Home

Subscriber

Server

P-CSCF

Application Server or

OSA Gateway

IMS

GPRS/ UMTS

SIP/SDP

IMS signalling

IP Flows

S-CSCF

UE PDF

SIP proxy infrastructure (CSCFs)

integrated with 3G networks elements (HSS, GGSN -via the PDF-)

Tesis Doctoral 10

4G research efforts

� Research efforts such as mobility, QoS and AAA in IP(v6) based networks

� Many existing solutions, challenge to integrate them

� Tests show that 4G can support Multimedia applications (which are the main applications concerned with session setup)

� Some works about session setup, but covering partial issues

Tesis Doctoral 11

State of the art vs. thesis innovation & objectives

� IMS already fulfils our idea� Semi walled garden business model

�But there is room to fit our research objectives:� Enhance and migrate IMS it to 4G networks with

many access technologies

� Support “non proxied” applications (e-mail)

� From partial 4G solutions to a complete framework

� Cover and compare all levels, entities, systems, business models, scenarios

Tesis Doctoral 12

Outlook

� Introduction

� State of the Art

� Integrating Sessions: Requirements

� Sessions are split, advantages and requirements to integrate them

� Sessions in the different entities

� Business models, Session Integration

� Users’ Profiles

� 4G Proposed Architecture and Session Setup Support

� Signaling

� Validation

� Conclusions

Tesis Doctoral 13

The 4 entities

� They control different aspects of the subsessions standing for a service

� Conferees (e.g. caller & callee in phone calls)

� VASPs: Services providers (they are also conferees)

� Proxies

� Network provider

Tesis Doctoral 14

Terminal dependentParameters:Screen size,

processing power…

3rd party resourcedependent parameters

(network):mean BW, peak BW,

error rate…

Mix:Codecs to employ,…

Session setup parameters

Network dependent parameters may be priced and related to users’ profiles. Which user profile should be followed when setting up sessions?: The Best, Caller’s one, …?

Proposal: include cost sharing in session setup negotiation

Tesis Doctoral 15

Business models, features to achieve

� Single sign-on

� Unified & non duplicated billing

� Service bundles, packaging

����� Need of aggregating sessions

� See whether the next-presented business models can fulfill these features

Tesis Doctoral 16

Network operator

Trust

relationship

3rd Party Service Providers

3rd Party Service Providers

Trust

relationship

Trust

relationship

Trust relationship Trust relationship

Internet Business model

� Not possible to aggregate sessions and thus to offer advanced features

� However, we need to support it

Tesis Doctoral 17

Network operator + Service provider

Trust

relationship

Telephony Business model

� Easy to aggregate sessions and offer advanced features

� Will be overcome in 4G networks

Tesis Doctoral 18

3rd Party Service Providers

Trust

relationship

Semi-walled garden business model

� To aggregate sessions and offer advanced features we to design appropriate mechanisms in 4G networks (Thesis Topic)

Trust relationship

Network operator

Tesis Doctoral 19

Users’ Profiles

� The NVUP. More complex than flat rates?

� Deutsche Telekom President: “create different QoS classes”…

� but “Interface” to the users simple (flat rates)

� A problem: Application profiles may differ with NVUP. Example:

� NVUP discount on AF traffic from 20:00 to 8:00.

� News Streaming: Discount from 21:00 to 7:00

� One of the pieces needed to solve it: the SVUP. Proposal to integrate the profiles (NVUP & applications)

Tesis Doctoral 20

Conclusions

� Benefits of Semi-walled garden model

� QoS-enabled data transport seen as another service

� Need to integrate services’ sessions

� Cost sharing

� User profiles, NVUP; and the SVUP as a way to integrate all the profiles

� Need also to support Internet model and non IMS applications, coexistence

� See how to achieve this in 4G networks

Tesis Doctoral 21

Outlook

� Introduction

� State of the Art

� Integrating Sessions: Requirements

� 4G Proposed Architecture and Session Setup Support

� Design needed aspects, session setup techniques in different scenarios

� Systems

� Orchestration

� Signaling

� Validation

� Conclusions

Tesis Doctoral 22

CN

Internet

AN

Systems

QoSB

QoSB

MMSP

MMSP

AA

AAA

Tesis Doctoral 23

CN

Internet

AN

Systems-QoS

QoSB

QoSB

MMSP

MMSP

AA

AA

Tesis Doctoral 24

QoS System modules

� Control network usage not only for QoS but also for SLAs issues e.g. police NVUP: B.E.<64 kbps

� QoSBrokers, Hierarchical� Push fine QoS control to the “edges”

� QoSBroker: PDP (like IMS PDF) + network management ���� extra QoS handling possibilities

� Proposal specialize QoSBroker in network management and not in user control� But still QoS tailored to users and applications thanks to

interactions with AAA and MMSP

� Implicit signaling… and QoSB gets user related data from AAA

� Controls network consumption and informs AAA

Tesis Doctoral 25

DiffServ CNNo access control,No sessionNo need of flow-userassociation

Internet

IntServlike AN,Access control,Sessions

IntServlike ANQoS

Broker

QoS Broker

QoS Broker

ER

ER

ERER

ARAR AR AR

CR

CR

CR

CR

Measurement

system

AAA

system

Measurement

system

MMSP

VASP

Tesis Doctoral 26

CN

Internet

AN

Systems-MMSPMulti Media Service provisioning Platform (i.e. SIP proxies)

QoSB

QoSB

MMSP

MMSP

AA

AAA

Tesis Doctoral 27

MMSP modules

� Like in IMS, hierarchical split: AN-MMSP, CN-MMSP

� Match with the QoS split

� P-CSCF + S-CSCF in the AN-MMSP

� AN-MMSP does the QoS SETUP and needs to keep its state (no need in IMS since we have only QoS policy transfer) ���� Extra QoS handling possibilities than in IMS

� All SIP routing via the CN-MMSP, alleviates this heavy task to the AN-MMSPs

Tesis Doctoral 28

CNCN

ANMMSP

MMSPInternet

AAA system

(registrar

service)

QoS

system

AAA

System

VASP

Users

AN

MMSP

AN

MMSP

MMSP

AN

MMSP

Tesis Doctoral 29

CN

Internet

AN

Systems-AAA

QoSB

QoSB

MMSP

MMSP

AA

AAA

Tesis Doctoral 30

AAA modules & decentralization proposal

� Aggregates the sessions other entities produce

� NAS: access session, user-packet mapping

� Decentralization: Not thesis main goal but it’s an important aspect to handle

� Decentralize accounting and authorization: Delegation to AN-AA server:� Diameter credit control���� credit server. Plus accounting

consolidation

� Authorization by transfer of selected parts of the user profile (SAML). Concerns in roaming

� Authentication keeps being centralized in the CN_AAA home server

Tesis Doctoral 31

DiffServ CN

IntServlike AN

AA

AAAInternet

MMSP

QoS System

MMSP

VASP

NAS Users

Tesis Doctoral 32

Orchestration

� Authorization or distribution of users profiles?

� Proposal: deliver profiles to MMSP and QoSBroker. They are trusted and may represent a big % of the total subsessions & services

AAA Client and AAA system to understand services

delivering parts of the user profile to not fully trusted AAA clients (service providers)

Performance KOPrivacy KO

Tesis Doctoral 33

Orchestration

� Several possibilities to authorize transport and services:

� MMSP����AAA, MMSP����QoSB

� MMSP obtains all the relevant user data from the AAA and then can ask for user and application tailored QoS

� VASP����AAA, VASP����QoSB, QoSB����AAA

� the AAA does not need to deliver user profile to the VASPs who, still, can ask for QoS to the QoSB. QoSB will obtain the missing data from the AAA

Tesis Doctoral 34

Orchestration

� AAA as sole network contact point:

� VASP����AAA, Terminal����QoSB, QoSB����AAA

� “Internet” scenarios

� No entity informs the AAA about the application, QoS based on NVUP

� Terminal�AAA (registration, done in every scenario)

� Terminal����QoSB, QoSB����AAA

� Thanks to the QoSB-AAA interaction we support more scenarios than in IMS

Tesis Doctoral 35

Conclusion

� Holistic approach

� Solutions to give coherence to the session setup split presented before

� Many scenarios and possibilities evaluated (complete the evaluation with simulation)

� Coexistence of the several proposals and heterogeneous environments

� Scalability AN-CN

� QoS Setup in first SDP offer/answer exchange

Tesis Doctoral 36

Outlook

� Introduction

� State of the Art

� Integrating Sessions: Requirements

� 4G Proposed Architecture and Session Setup Support

�Signaling

� Closes the solution

� Validation

� Conclusions

Tesis Doctoral 37

Contributions summary

� Standard protocols enhanced to fit our needs and to co-operate between them

� Session identification and its exchange

� Aggregation of sessions

� Heterogeneous QoS and NAS sessions supported

� Registration

� Setup in MMSP, VASP, Internet scenarios

� SAML allows transferring user profile to AN-AA and thus delegating authorization to it.

Tesis Doctoral 38

Outlook

� Introduction

� State of the Art

� Integrating Sessions: Requirements

� 4G Proposed Architecture and Session Setup Support

� Signaling

� Validation

� Methods to design 4G networks

� Simulation scenario

� Test results for the “MN and MMSP strategies”

� Conclusions

Tesis Doctoral 39

ScenarioThe 4 CNs

CN

CN

CN

CN

Tesis Doctoral 40

Scenario1 of the 4 CNs

Internet

AN

AN

AN

AN

AN

AN

AN

AN

QoSB

MMSP

AAA

Tesis Doctoral 41

Scenario1 of the 32 ANs

CN

QoSB

MMSP

AA

Tesis Doctoral 42

System load

� Nodes processing speed calculated to support 64 calls/s

� AN-MMSP calculations for the MN strategy

� 1 major Test

� Several measurements

� 2 minor tests

Tesis Doctoral 43

Call setup time…the system is overloaded!!

Tiempos de inicio, fin y duración del establecimiento de las llamadas.

64 llamadas/s. Estrategia "MMSP"

12 16 20 24 28 32 36 40 44 48

Lla

mad

as (

ord

en

ad

as p

or

tiem

po

de i

nic

io)

Tiempo (s)

Tesis Doctoral 44

However, no node is overloaded!!e.g. procesing time in the AN-AA…

Tiempo de procesamiento de los mensajes en un AN-AA

64 llamadas/s. Estrategia MMSP. Cada punto es un mensaje

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

12 16 20 24 28 32 36 40 44 48

Tiempo de de entrada del mensaje (s)

Tie

mp

o d

e p

rocesam

ien

to d

el

men

saje

(s)

Tesis Doctoral 45

… but the AN-MMSP in the MMSP strategy

Tiempo de procesamiento de los mensajes en un AN-MMSP.

64 llamadas/s. Estrategia MMSP. Cada punto es un mensaje

0

0.5

1

1.5

2

2.5

3

12 16 20 24 28 32 36 40 44 48

Tiempo de entrada del mensaje (s)

Tie

mp

o d

e p

roceso

del

men

saje

(s)

Tesis Doctoral 46

System Load

� No node overload but the system is overloaded (session setup time increases)

� Other tests� Minimum load

� != in setup time between the 2 strategies <=> the AN-MMSP speed

� maximum stable load

� this difference is bigger (45%)

� Effects of nodes on each other in a complex architecture

� Need for simulations, analytical results not enough even for this small experiment

Tesis Doctoral 47

Peak of calls

� Call rate

� low rate,

� high rate, (during 1 s)

� low rate

� Measurements

� Session setup time

� Nodes processing speed

Tesis Doctoral 48

Call Setup time. MMSP strategy

Tiempo de establecimiento de las llamadas.Pico de llamadas. Estrategia MMSP

0

1

2

3

4

5

6

7

8

9

12 22 32 42 52 62 72 82

Tiempo de inicio de la llamada (s)

Tie

mpo d

e e

sta

ble

cim

iento

(s)

Tesis Doctoral 49

Call Setup time. MN strategy…lower peak and shorter time to recover

Tiempo de establecimiento de las llamadas.Pico de llamadas. Estrategia MMSP

0

1

2

3

4

5

6

7

8

9

12 22 32 42 52 62 72 82

Tiempo de inicio de la llamada (s)

Tie

mpo d

e p

rocesam

iento

(s)

Tesis Doctoral 50

The CN nodes present a peak...

Tiempo de procesamiento de los mensajes en un CN-AAA. Pico de llamadas. Cada punto es un mensaje. Estrategia MN

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

12 22 32 42 52 62 72 82

Tiempo de entrada del mensaje (s)

Tesis Doctoral 51

…and not the AN ones

Tiempo de procesamiento de los mensajes en un AN-MMSP.

Pico de llamadas. Cada punto es un mensaje. Estrategia MN

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 10 20 30 40 50 60 70 80 90 100

Tiempo de entrada del mensaje (s)

Tie

mpo d

e p

roceso d

el m

ensaje

(s)

Tesis Doctoral 52

But for the AN-MMSP in the MMSP strategy

Tiempo de procesamiento de los mensajes en un AN-MMSP.

Pico de llamadas. Cada punto es un mensaje. Estrategia MMSP

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

0 10 20 30 40 50 60 70 80 90 100

Tiempo de entrada del mensaje (s)

Tie

mpo d

e p

roceso d

el m

ensaje

(s)

Tesis Doctoral 53

Peak of calls

� AN-CN split advantage, peak present only in central nodes

� Influence of the AN-MMSP in “recovering”: in the “MMSP strategy” it presents a processing time peak and this “strategy” takes more time to “recover”

Tesis Doctoral 54

Conclusion, methods to design 4G

� 1st holistic simulation

� Many nodes interacting, analytical approach not enough even in our small model

� Benefits of the hierarchical approach (peak of calls)

� Bottle necks: nodes with many interactions (AN-MMSP)=> reduce their load=> SIP routing at CN-MMSP

Tesis Doctoral 55

Outlook

� State of the Art

� See what is profitable, research opportunities matching our

objectives

� Integrating Sessions: Requirements

� Sessions are split, advantages and requirements to integrate them

� 4G Proposed Architecture and Session Setup Support

� Design needed aspects, session setup techniques in different

scenarios

� Signaling

� Closes the solution, important for understanding simulations

� Validation

� Methods to design 4G networks

� Conclusions

Tesis Doctoral 56

Conclusions

� IMS evolution and enhancement towards 4G

� First holistic 4G framework covering several scenarios, entities, systems…

� Semiwalled model achieved but keeping Internet paradigm: transport and service separation

� Other scenarios supported

� Design decisions & approaches compared and analyzed

Tesis Doctoral 57

Conclusion, avenues for research

� Multiparty calls, mobility=> extend our framework

� Anonimization, pseudonyms: single sign on vs. not tracking user activity

� Multicast MMSP+QoS interaction

Tesis Doctoral 58

Conclusion, forecast for our proposal

� Consumers’ preferences determine all the aspects in the business (stop vs. non stop flights costs vs. price)

� Users need to find any advantage in the services

� Our framework is a service provisioning platform that may help create better services accepted by the users …

� Or just compete in price but keeping user control

Contribución al Desarrollo de Soluciones Contribución al Desarrollo de Soluciones Para la Integración de Métodos de Para la Integración de Métodos de Establecimiento de Sesión en Redes 4GEstablecimiento de Sesión en Redes 4G

((ContributionContribution toto DesigningDesigning SuitableSuitableSessionSession SetupSetup SolutionsSolutions in 4G in 4G NetworksNetworks))

Autor: D. Antonio Cuevas CasadoAutor: D. Antonio Cuevas Casado

Director: Dr. José Ignacio Moreno NovellaDirector: Dr. José Ignacio Moreno Novella

TESIS DOCTORALTESIS DOCTORAL

Departamento de Ingeniería Telemática

Doctorado en Tecnologías de las Comunicaciones