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End-to-End QoS Provisioning in UMTS End-to-End QoS Provisioning in UMTS networksnetworks

-Midterm Presentation-Midterm Presentation

Group 995Group 995Haibo WangHaibo Wang

Devendra PrasadDevendra Prasad04gr995@kom.aau.dk04gr995@kom.aau.dk

Supervisors:Supervisors:Hans-Peter SchwefelHans-Peter Schwefel

Oumer TeyebOumer Teyeb

2005-2-222005-2-22

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Presentation outlinePresentation outline

1.1. MotivationMotivation2.2. Background Background 3.3. Problem Delimitation Problem Delimitation 4.4. Preliminary Simulation Preliminary Simulation 5.5. Proposed QoS algorithms Proposed QoS algorithms 6.6. Future work Future work

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What is End2End QoS?What is End2End QoS?• Quality of ServiceQuality of Service

is a set of requirements to be met by the network while transportis a set of requirements to be met by the network while transporting a traffic flow.ing a traffic flow.

• Only the QoS perceived by end-user matters [1]Only the QoS perceived by end-user matters [1]

1.1. MotivationMotivation

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QoS provision mechanisms and QoS control mechanisms [2]:QoS provision mechanisms and QoS control mechanisms [2]:• QoS provision mechanisms include parameters mapping, admission anQoS provision mechanisms include parameters mapping, admission an

d resource reservations schemes.d resource reservations schemes.• QoS control mechanisms consist of traffic shaping, scheduling, policing QoS control mechanisms consist of traffic shaping, scheduling, policing

and control.and control.

QoS mechanismsQoS mechanisms

• Delay Delay

• Jitter Jitter

• Loss RateLoss Rate

• ThroughputThroughput

These parameters reflect the traffic flow through the These parameters reflect the traffic flow through the network.network.

End2End QoS ParametersEnd2End QoS Parameters

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Offered QoS through SLAOffered QoS through SLA

• QoS can be offered by network service provider in terms of Service Level QoS can be offered by network service provider in terms of Service Level Agreement (SLAs)Agreement (SLAs)i) Network Availabilityi) Network Availabilityii) Guaranteed bit-rateii) Guaranteed bit-rate

iii) Payment modeliii) Payment model iv) Other legal necessitiesiv) Other legal necessities

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Why is QoS needed in Why is QoS needed in UMTS?UMTS?

A main challenge for UMTS is A main challenge for UMTS is to convey various types of trato convey various types of traffics on the same medium whffics on the same medium while meeting their different Qoile meeting their different QoS requirements, especiallyS requirements, especially fofor real-time applications.r real-time applications.

UMTS Release 4

UMTS Release 5

Note: UMTS core networks evolution to all IP backbone.

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The E2E UMTS QoS case we are investigatingThe E2E UMTS QoS case we are investigating

UEs UTRAN SGSN GGSN Internet

Application Servers

Two domain involved form end-2-End QoS point of view:

UMTS domain QoS and IP domain QoS

2. Background2. Background

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2.1 UMTS QoS Domain: 2.1 UMTS QoS Domain: End2End QoS ArchitectureEnd2End QoS Architecture

• 3GPP layered structure [1]3GPP layered structure [1]

TE MT RAN CN EDGE NODE

CN Gateway

TE

UMTS

End-to-End Service

TE/MT Local Bearer Service

UMTS Bearer Service External Bearer Service

UMTS Bearer Service

Radio Access Bearer Service CN Bearer Service

Backbone Bearer Service

RAN Access Bearer Service

Radio Bearer Service

Physical Radio Bearer Service

Physical Bearer Service

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UMTS QoS - UMTS QoS - UMTS QoS classesUMTS QoS classes

Traffic class Conversational class

conversational RT

Streaming classstreaming RT

Interactive classInteractive best

effort

BackgroundBackground best effort

Fundamental characteristics

-Preserve time relation (variation) between information entities of the stream

Conversational pattern (stringent and low delay )

-Preserve time relation (variation) between information entities of the stream

-Request response pattern -Preserve payload content

-Destination is not expecting the data within a certain time

-Preserve payload content

Example of the application

-voice -streaming video -Web browsing -background download of emails

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UMTS QoS provisioningUMTS QoS provisioning

• Existing UMTS QoS mechanisms:Existing UMTS QoS mechanisms:- QoS profile- QoS profile- Traffic Flow Template (TFT)- Traffic Flow Template (TFT)- PDP context- PDP context

• What is missing in 3GPP standardization?What is missing in 3GPP standardization?- UTRAN part: QoS parameters mapping to Radio Resource - UTRAN part: QoS parameters mapping to Radio Resource MaManagement strategiesnagement strategies- UMTS core network part: IP layer transport mechanisms on the - UMTS core network part: IP layer transport mechanisms on the Gn Gn and Gi interfaceand Gi interface

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2.2 IP QoS 2.2 IP QoS DiffServ and InterServ comparisonDiffServ and InterServ comparison

Integrated servicesIntegrated services Differentiated servicesDifferentiated services

State in routers (e.g., scheduling State in routers (e.g., scheduling buffer management)buffer management)

Per-flowPer-flow Per- AggregatePer- Aggregate

Traffic classification basisTraffic classification basis Several header fieldsSeveral header fields The DS field (6 bits) of The DS field (6 bits) of the IP headerthe IP header

Admission control Admission control RequiredRequired Required for absolute Required for absolute differentiation onlydifferentiation only

Signaling protocolSignaling protocol Required (RSVP)Required (RSVP) Not required for relative Not required for relative schemes; absolute schemes; absolute schemes need semi-schemes need semi-static reservations or static reservations or broker agentsbroker agents

Coordination for serviceCoordination for service

differentiationdifferentiationEnd-to-end LocalEnd-to-end Local (per-hop)(per-hop)

ScalabilityScalability Limited by the Limited by the number of flowsnumber of flows

Limited by the number of cLimited by the number of classes of servicelasses of service

Network managementNetwork management Similar to circuit-Similar to circuit-switched networksswitched networks

Similar to existing IP Similar to existing IP networksnetworks

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IP BearerLayer

AccessBearerLayer(eg. UMTSBearer)

LocalUE

SGSN

Scope of PDP Context

IP Bearer Service

RemoteAccessPoint

Gn/Gp

GGSN

RemoteHost

GGSNUE RemoteAP

RemoteHost

Backbone IPNetwork

3. 3. Problem DelimitationProblem Delimitation

Network Architecture for QoS Conceptual Models

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Problem StatementProblem Statement

1. External IP network: IETF standard QoS mechanism – DiffServ or InterServ

2. UMTS network domain:

1) QoS classes mapping between External IP QoS classes and UMTS QoS classes, and

UMTS Bear Service (BS) attributes mapping to Core Network (CN) BS and Radio

Access Bearer (RAB) and further to Radio BS and Iu BS.

2) Call Admission Control in every multiplexing point (GGSN, SGSN, etc)

3) GGSN policing: check downlink flow and filter it according to TFT

4) Scheduling and congestion mechanisms in CN transmission (I,e, WFQ, WRED, etc)

5) QoS differentiation implementation in RRM

3) Other open issues: Application level End2End QoS provisioning, i.e, SIP signalling

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State of the ArtsState of the Arts1.1. Advanced Radio Resource Management for Wireless Services(ARROW) Advanced Radio Resource Management for Wireless Services(ARROW)

: : www.arrow-ist.eswww.arrow-ist.esThis project aims at providing advanced Radio Resource ManagementThis project aims at providing advanced Radio Resource Management(RRM) and Quality of Service (QoS) management solutions, for both(RRM) and Quality of Service (QoS) management solutions, for bothUTRA-TDD and UTRA-FDD modes. It includes packet access, UTRA-TDD and UTRA-FDD modes. It includes packet access, Asymmetrical traffic and high bit rate (2 Mbit/s) services for multimedia IPAsymmetrical traffic and high bit rate (2 Mbit/s) services for multimedia IP

based applications. based applications.

Although ARROWS concentrates on the QoS aspects of UTRAN, a Although ARROWS concentrates on the QoS aspects of UTRAN, a global QoS framework is proposed, which is relevant with our work.global QoS framework is proposed, which is relevant with our work.

2. 2. Advanced Services by Mastering UMTS (SAMU) : Advanced Services by Mastering UMTS (SAMU) : www.samu.crm-paris.comwww.samu.crm-paris.comThe innovative work in QoS from SAMU includes UMTS/IP QoS mappingThe innovative work in QoS from SAMU includes UMTS/IP QoS mappingarchitecture and UMTS link layer optimization for TCP. The architecture architecture and UMTS link layer optimization for TCP. The architecture includes both mapping between IP DiffServ and UMTS bearer and mappingincludes both mapping between IP DiffServ and UMTS bearer and mapping from UMTS bearer to lower layer. from UMTS bearer to lower layer.

We refer to the mapping between IP DiffServ and UMTS Bearer from this We refer to the mapping between IP DiffServ and UMTS Bearer from this project.project.

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3.3. Simulation of Enhanced UMTS Access and Core Networks (SEACORN) : Simulation of Enhanced UMTS Access and Core Networks (SEACORN) : www.seacorn.ptinovacao.ptwww.seacorn.ptinovacao.pt

Development, and implementation of resource management algorithms enablinDevelopment, and implementation of resource management algorithms enablin

g QoS provisioning and differentiation while optimizing resource efficiencyg QoS provisioning and differentiation while optimizing resource efficiency This project contribute a system level UMTS network simulator based on NS-2,This project contribute a system level UMTS network simulator based on NS-2, named Enhanced UMTS Radio Access Network Extensions (EURANE), which named Enhanced UMTS Radio Access Network Extensions (EURANE), which We chose as the base of our simulator.We chose as the base of our simulator.

• Contributions and drawbacks of these related works:Contributions and drawbacks of these related works:a). Many E2E QoS frameworks were proposed but solid implementation and simua). Many E2E QoS frameworks were proposed but solid implementation and simulation output are still missing. lation output are still missing. b). QoS attributes mapping are designed but not implemented.b). QoS attributes mapping are designed but not implemented.

c). These work more focused on the RRM implementation, no core network QoS mc). These work more focused on the RRM implementation, no core network QoS mechanisms are considered.echanisms are considered.d). None of the framework gives a clear picture about the impact of mixing real-tid). None of the framework gives a clear picture about the impact of mixing real-time and non-realtime traffics on the QoS aspects.me and non-realtime traffics on the QoS aspects.

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Problem DelimitationProblem Delimitation

• Traffic: Mixed types of user data (real-time and non-real-time) flow from Traffic: Mixed types of user data (real-time and non-real-time) flow from external application servers to UMTS User Equipments (UEs). And we onlexternal application servers to UMTS User Equipments (UEs). And we only focus on downlink traffic flow.y focus on downlink traffic flow.

• For Internet/External network QoS -> IETF DiffServ approach was chosen.For Internet/External network QoS -> IETF DiffServ approach was chosen.

Reason: more scalable and easy to manage when more than one network Reason: more scalable and easy to manage when more than one network operator involved.operator involved.

• In UMTS Core Network side:In UMTS Core Network side:1) Mapping mechanism from DiffServ QoS classes to UMTS QoS classes in 1) Mapping mechanism from DiffServ QoS classes to UMTS QoS classes in GGSNGGSN

2) Call Admission Control in GGSN considering required QoS profile and a2) Call Admission Control in GGSN considering required QoS profile and available equivalent bandwidth vailable equivalent bandwidth 3) Scheduling and queuing mechanisms to differentiate different UEs acc3) Scheduling and queuing mechanisms to differentiate different UEs according to their UMTS service classes (Conversational, Streaming, Interactording to their UMTS service classes (Conversational, Streaming, Interactive, Background)ive, Background)

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Simulation Tool – Network Simulator Simulation Tool – Network Simulator version 2 (NS-2) and its UMTS version 2 (NS-2) and its UMTS

extensionextension

•No PDP Context Functionality.No PDP Context Functionality.•SGSN and GGSN are “Routers” from standard NSGSN and GGSN are “Routers” from standard NS-2.S-2.•DiffServ functionalities are availableDiffServ functionalities are available•Some buffer management algorithms are available Some buffer management algorithms are available for congestion control, i.e. Random Early Discard (REfor congestion control, i.e. Random Early Discard (RED) D)

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4. Preliminary Simulation 4. Preliminary Simulation

Simulation Scenarios:Simulation Scenarios:1. Network Topology1. Network Topology

UE2

UE3

UE1

Node B SGSNRNC GGSN

Appl. Server1

Appl. Server2

Appl. Server3

2Mb

2Mb

2Mb

10Mb

10Mb

1Mb

10Mb

10Mb

10Mb

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2. Traffic Model2. Traffic Model• Constant Bit Rate (CBR) source for real-time applicationsConstant Bit Rate (CBR) source for real-time applications• Exponential traffic source for non-realtime applications Exponential traffic source for non-realtime applications • All traffic is working on UDP protocolAll traffic is working on UDP protocol

3. Mobility Model3. Mobility Model nonenone

4. Propagation Model4. Propagation Model Ideal, Ideal,

Standard NS-2 error model to be set in futureStandard NS-2 error model to be set in future

5. QoS mechanism5. QoS mechanism Best EffortBest Effort

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Simulation Result 1Simulation Result 1

User throughput when the total traffic load is lower then the User throughput when the total traffic load is lower then the bandwidth in Core network (SGSN-GGSN)bandwidth in Core network (SGSN-GGSN)

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Simulation Result 2Simulation Result 2

User throughput when the total traffic load is higher then the User throughput when the total traffic load is higher then the bandwidth in Core network (SGSN-GGSN)bandwidth in Core network (SGSN-GGSN)

Slightly overload

Heavily overload

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ConclusionConclusion

In case of Best Effort transmission, the real-time traffics wiIn case of Best Effort transmission, the real-time traffics will suffered from the mixing with non-realtimell suffered from the mixing with non-realtimeTraffics in case of network congestion.Traffics in case of network congestion.

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5. Proposed End2End QoS algorithms5. Proposed End2End QoS algorithms

CACMapping

PDP Context generation through event based

Database (At the time of eventGenerator and use it for CAC

GGSNSGSN

UE1

UE1

UE2

UE3

Edge RouterCore Router

DS 1

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PDP Context generation through event PDP Context generation through event basedbased

•Event based PDP generation, Event based PDP generation,

•Acknowledgement based database for PDP Context Acknowledgement based database for PDP Context

•Event based Traffic generation,Event based Traffic generation,

•1,2,3,4 is Available Bandwidth and 6 is an 1,2,3,4 is Available Bandwidth and 6 is an acknowledgementacknowledgement

UE Node B

Database: UE id,APN,BW Available,

RNC SGSN GGSN1 3 4 5 6

7Acknowledgement

AS

Total Duration : 60ms

Duration : 50ms

Duration : 55ms

2

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MappingMapping

•UMTS QoS Attributes are Guaranteed Bit Rate and SDU size.UMTS QoS Attributes are Guaranteed Bit Rate and SDU size.

•IP QoS Attributes are burst size and arrival rate stored in traffic proIP QoS Attributes are burst size and arrival rate stored in traffic profile of the SLA. [2]file of the SLA. [2]

•Differentiated Services considered.Differentiated Services considered.

•IPv4 header field TOS is used for DSCP.IPv4 header field TOS is used for DSCP.

•Assured Forwarding is considered for the traffic class buffering.Assured Forwarding is considered for the traffic class buffering.

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MappingMapping --continuecontinue

•Assumptions are IPv4, AF for PHBAssumptions are IPv4, AF for PHB

Traffic Profile:Burst Size,

Arrival Rtes

Core Router: PHBScheduling,Buffering

DS1

GGSNGuaranteed Bit rate, SDU Size

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Call Admission ControlCall Admission Control

1. Incoming Traffic class,

2. Check with the Database for the Resource reservation,

3. Set priority based on the Available BW and Traffic class, I.e Real-time: High priority, Non Real-time: Low Priority,

4. Scheduling, policy setting

database

GGSN

ER1

2

4SGSN

External Net

3

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ConclusionConclusion•The most of technical paper or EU funded project proposed the the concThe most of technical paper or EU funded project proposed the the concept but none with the E2E aspect.ept but none with the E2E aspect.•As the emphasis is on the Multimedia Services , Hence the mapping betwAs the emphasis is on the Multimedia Services , Hence the mapping between the UMTS and the IP Network is the highest priority.een the UMTS and the IP Network is the highest priority.•The proposed algorithm will offset the limitation of an available simulatoThe proposed algorithm will offset the limitation of an available simulator with the implementation of Event based PDP Context and traffic generatir with the implementation of Event based PDP Context and traffic generation. on. •The purpose of the proposed topology is to design the algorithm which dThe purpose of the proposed topology is to design the algorithm which deals the End to End QoS aspect including mapping,Scheduling and resoureals the End to End QoS aspect including mapping,Scheduling and resource reservation.ce reservation.•The proposed algorithm will reduce the end2end delay and packet loss pThe proposed algorithm will reduce the end2end delay and packet loss probabilityrobability

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Future WorkFuture Work

•Implementation of proposed topology and validation of Implementation of proposed topology and validation of proposed algorithm.proposed algorithm.

•To show that the mix of non real time application makes To show that the mix of non real time application makes the real time application to suffer.the real time application to suffer.

•To show the proposed queuing and scheduling technique To show the proposed queuing and scheduling technique will improve the real time application When it mix with non will improve the real time application When it mix with non real time application.real time application.

•To show the Guaranteed bit rate per user can be achieved To show the Guaranteed bit rate per user can be achieved even during the congestion .even during the congestion .

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ReferencesReferences

[1] 3GPP TS23.107[1] 3GPP TS23.107[2] SAMU project, QOS Deliverable SP2-D1, [2] SAMU project, QOS Deliverable SP2-D1,

http://samu.crm-paris.com/, 2001.http://samu.crm-paris.com/, 2001.

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BackupBackup

Proposed Mapping in ASMU project [2]