Satellites in Next Generation Networks QoS issues Stéphane Combes, R&D, Alcatel Space

ITU-T workshop on Satellites in IP and Multimedia Geneva, 9-11 December 2002

Satellites in Next Generation NetworksQoS issuesStéphane Combes, R&D, Alcatel Space

Satellite NGN : QoS issues — 2 All rights reserved © 2002, Alcatel Space

Content

> What NGN and QoS mean ? End-to-end QoS - Layered model

> Current Satellite Systems Access network architectures- QoS

> Enhancing the current situation Expected improvement- Architectures

> Satellite in NGN- Status- Future Activities


NGN In Short

> NGN (Next Generation Networks) means Uncoupling services and transport provision (like IN) Multimedia/multi-services/multi-networks Packet-based (IP) QoS and security are MUST !

> QoS for NGN means QoS aware network equipment Admission control mechanisms Interaction between call signalling, resources

management and admission control


NGN End-to-End QoS

Access Network

SIP

SIP

End User

SIP

Home Network

Visited Network

Applic.

1

QoS Selection

S-CSCF

P-CSCF

Core Network

Originating side Terminating side

SIP2

Applic.

S-CSCF

Home Network

SIP

SIPSIP

End User

Access Network

Visited Network

3

QoS Selection

P-CSCF

4QoS Negotiation

55

Bearer setup

Bearer setup


NGN General Layered QoS Model

Session Layer

Connection Control Layer

Transport Layer

URIURI

End IP @ End IP @

Hop

routing

Hop

routing

Hop

routing

Hop

routing

EndIP @

EndIP @

QoS info

QoS infoQoS info

QoS infoQoS info

QoS infoQoS info

QoS infoURI

QoS info

Application Layer

QoS infoQoS info

enduser

enduser

Core Network

Access Network

SIP

AGEnd User

P-CSCF

AC

COPS

Session Layer

Transport Layer

Connection Layer

COPS

PCF

ARC


Current Satellite SystemsAccess Network Architectures

> DVB-RCS architecture 2-way multimedia IP based DVB-S forward link MF-TDMA return link ATM or MPEG

segmentation Packet based DAMA

Corporate

RAS

SatelliteTerminal (ST)

Telcos

Transportnetwork

ISPs

HUB

Return link

Return linkMF-TDMA ATM orMPEG

Forward linkTDM DVB-S

STLAN

LAN

ST AccessNode

ManagementCentre

RMG

SME/Enterprise

ISP POP

Multi-Dwelling

Telco POP

LAN

SOHO/RES

PSTN

LANLAN

NCC i

C o rpo ra te

ST

A ccessN etwo rk

M a na g em entISP

M NM S

Tra ffi c link

Sig na lling link

LA N

ST

ST

Sa telliteO n Bo a rd Pro cesso r

(cell o r circuit sw itch ing )

A ccessC o ntro l

functio ns fo rIn tera ctiveN etwo rk i

C o rpo ra te

ISP

ST

Sig na lling link

STInteractiveNetw ork i

InteractiveNetw ork j

> Regenerative Satellite architecture Multi-Gateway Mesh: direct ST-to-ST ATM or MPEG on-board switching DVB-S downlink DVB-RCS uplink


Current Satellite Systems QoS> Service Level Agreement (SLA)

Satellite network operator grants a given bandwidth (usually constant) to each service provider for its pool of STs

Service providers grant subscribers a per ST traffic contract:

– Best effort with peak rate– Minimum guaranteed rate with a peak rate

> Static Admission Control At ST log-on Upon management action

> Traffic Contract Enforcement Return link: DAMA algorithms using capacity categories

defined in DVB-RCS: CRA, RBDC, VBDC, FCA Forward link: IP and/or ATM traffic management (policy,

shaping) in the Hub


Enhancing the current situationExpected improvements

> STEP 1 - Adding flexibility & better QoS in the access Priority mechanisms between Real-Time and non Real-

Time applications according to IP CoS indications (DiffServ DSCP)

Coupling between IP and MAC processes in ST Traffic contract modification of the ST from NMC or upon

user’s request (e.g. using a Web-based interface)

> STEP 2 - Interworking between access and core NGN enabled networks Dynamic admission control based on specific satellite

signalling mechanisms Dynamic admission control and resource reservation

coupled with call signalling protocols (SIP, H323)


Enhancing the current situation Star Architecture

Call

Endpoint

Call S erver

S T H UB

Forwarding

A pplicat ion

PDP

A A A

T RA N S PO RT PRO VI DER

S ERVI CE PRO VI DER

Call

Endpoint

Call S ignalling

Q oS S ignalling

Q oS S ignalling

CDRs on # # #

CDRs on

I P@

Connect ion S ignalling

Connect ion

S ignalling

M edia fl ow

RS VP

S I P

Q oS S ignalling

CO PS

N CC

T ransport PEP

proxyAG

DA M A

S I P

RS VPAGAG

+T ransport PDP

Session protocol

Network transport

QoS protocol

Satellite transportQoS protocol

(DVB-RCS extension)

Network transport

Policy control protocol


Enhancing the current situation Mesh architecture

Call

Endpoint

Call S erver

S TH UB

Forwarding

A pplicat ion

PDP

A A A

T RA N S PO RT PRO VI DER

S ERVI CE PRO VI DER

Call S ignalling

Q oS S ignalling

CDRs on # # #

CDRs on

I P@

Connect ion S ignalling

M edia fl ow RS VP

S I P

Q oS S ignalling

CO PS

N CC

T ransport PEP

LPDPDA M ACall

Endpoint

S T S I P

proxy AG

AG

AG

RS VP

RS VP

+ T ransport PDP


Satellite in NGNStatus

> Current NGN-related terrestrial network activity is huge Standards : IETF, ITU, ETSI Planned roll-out for Cable, UMTS and DSL access

networks

> Satellite system is weak in NGN picture Only pure physical/access layer standards (DVB-RCS) No QoS support definition No satellite/terrestrial interworking defined Current proprietary solutions and weak QoS May slow down the up-taking of NGN and their

associated services through satellite


Satellite in NGNFuture Activities> Determine typical applications/services scenarios

requiring QoS support and their requirements for integration of Broadband Multimedia systems

> Define QoS architectures, identify functional entities and interfaces. Analyse call signalling/resources management/ admission control interactions

> Guarantee interoperability with terrestrial NGN protocols or propose extensions/profiles. Analyse specific processing or adaptations required in satellite access equipment at adaptation & access layers

> Propose potential extensions or adaptations to satellite access standards such as DVB-RCS : transparent +OBP based meshed systems

Satellites in Next Generation Networks QoS issues Stéphane Combes, R&D, Alcatel Space

Documents

Transcript of Satellites in Next Generation Networks QoS issues Stéphane Combes, R&D, Alcatel Space