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MMD Evolution

June 28, 2005

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Outline

• MMD Basics

• End-to-End Example– Packet Switched Video Telephony

• Legacy MS Domain Evolution

• Transition to MMD

• MMD Evolution

• 3GPP2 Project Roadmap

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Introduction

• 3GPP2 defines core standards for VoIP and multi-media services– Not just a replacement for circuit-switched voice– Other example services: voice/video conferencing,

PTT, Presence and Instant Messaging.• CDMA2000 packet network standards build on

results from the IETF and IMS-related standards from 3GPP

• 3GPP2 All-IP network is comprised of two domains:– Legacy MS Domain (LMSD)– Multimedia Domain (MMD.)

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LMSD

• The Legacy MS Domain provides support for existing mobiles (e.g., analog, IS-95-A, IS-95-B, IS-2000) with an IP core network.

• The Legacy MS Domain supports the features and capabilities provided in a legacy network in a manner transparent to the user.

• LMSD supports Transcoder Free Operation (TrFO) and Remote Transcoder Operation (RTO) operations.

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Multi-Media Domain

• Multi-Media Domain (MMD) provides support for SIP capable mobile stations in an IP core network environment.

• MMD supports multimedia sessions to and from SIP-capable mobile

• Also defines interworking with circuit switched networks via Media Gateways.

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IP Multimedia in 3GPP/3GPP2

• 3GPP/3GPP2 standards for IP Multimedia services– IP Multimedia Subsystem (IMS) in 3GPP–Multimedia Domain (MMD) in 3GPP2 (IMS plus CDMA

packet data transport and enhancements for CDMA operation.)

–3GPPs decided to harmonize core network. Now nearly identical at IMS level.

• Regulatory issues must be addressed – (VoIP surveillance, tax structure for internet services, E911 and position

location, etc.)

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Control

Bearer

Called PartyVisited Network

Called PartyHome Network

Calling PartyHome Network

Calling Party Visited Network

UE

P-CSCF

HSS

S-CSCFSIP

SIP

Diameter

UE

P-CSCF

AS

HSS

S-CSCF SIP AS

SIP

Diameter

I-CSCF

Diameter

DNS

BackbonePacket

NetworkRAN

BackbonePacket

Network RAN

Initiate SIP Invitation1

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Retrieve Subscriber Profile (if needed) 2

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3

3 Apply Service Logic

Retrieve Address of CLD Party Home Networkand Forward INVITE.

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4

Identify Registrar of CLD Party and Forward INVITE.5

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Retrieve Subscriber Profile (if needed) 6

6

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7 Apply Service Logic

Forward INVITE to CLD Party8

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SDP Negotiation / Resource Reservation Control9

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RTP Stream

Ringing / Alerting10

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Answer / Connect11

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Basic call flow

RTP Stream

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12 Session Active

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HRPD call flow (do we need it?)AT1 RAN PDSN SIP

ProxyAT2

CallInitated RUP: ConnectionRequest

EMFPA: ReservationOnRequest(Default Codec)

Admission Control

EMFPA: ReservationAccept

SIP: Invite (Codec List)SIP: Invite (Codec List)

SIP: 100 Trying

Connection Setup

PDSN RAN

Connection Setup

SIP: Invite (Codec List)

Granted QoS

EMFPA: ReservationOnRequest

(NonDefault Codec)

EMFPA: ReservationAccept

Admission Control

Granted QoS

Ring User

SIP: 180 RingingSIP: 180 Ringing

User Picks

SIP: 200 OKSIP: 200 OK

SIP: ACKSIP: ACK

Media Traffic

SIP: 183 SDP (NonDefault Codec)SIP: 183 SDP (NonDefault Codec)

EMFPA: ReservationOnRequest

(NonDefault Codec)

SIP: PRACKSIP: PRACK

SIP: 200 OKSIP: 200 OK

RTCMAC SubType 3: AttributeUpdateRequest

(MAC Configuration)

RTCMAC SubType 3: AttributeUpdateAccept

SIP: PRACKSIP: PRACK

Call Setup Delay

Call Setup Time = 2 * Conn Setup + 2 * RTD + QoS Activation

Granted QoSGranted QoS

Admission Control

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Packet Switched Video Telephony (PSVT)

• An example service for the MMD• Includes air interface, RAN, core network aspects,

and terminal procedures • Most procedures exist in current standards, e.g.

– X.S0011 Wireless IP Rev D– X.S0013 MMD Rev 0– IOS– C.S0024 HRPD Rev A– C.S0001 - C.S0006

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PSVT Components• Air Interface

– Service Options to be used for transporting SIP, Audio, Video, and RTCP traffic– Procedures for requesting appropriate air link QoS for these different traffic types

• IOS (A-interface)– Specifications for handoffs and cross paging of HRPD-1x hybrid terminals

• Packet Data Network– Identifies procedures for QoS establishment and flow treatment– Recommends header compression options– Procedures for packet data accounting

• MMD– Procedures for session setup using SIP– SIP compression and security procedures– Procedures for MMD accounting

• Following slides provide architecture and call flows.

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PSVT Reference Model

IPNetworks

PDSNRAN

Network A

PDSN RAN

Network B

I/S-CSCF I/S-CSCF

MSMS

SIP SignalingOTA/IOS SignalingMedia Control for Audio/VideoAudio Bearer PathVideo Bearer PathAAA/HSS InterfacesMP Interfaces

MRFP(optional)

MRFC(optional)

AAA

HSS

P-CSCF

AAA

HSS

P-CSCF

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PSVT Call Flow (tbd)S-CSCFP-CSCFPDSNRANMS-1

8. MediaFlow

1. SIP Capability Exchange (INVITE/183)

2. Bearer Resource Establishment

3. Indicate Bearer setup complete (UPDATE/200 OK)

5. Indicate MS-2 alerted (180 Ringing)

4. Called MS alerted

6. Called MS answers

7. Complete SIP session setup (200 OK/ACK)

MS-2MS-2 HN

Bearer ResourceEstablishment

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PSVT QoS-1

• Access networks enforce agreed QoS for different IP flows

SIPServers

Terminal BSC/AN PDSN PDSN BSC/AN Terminal

RLP Links GRE Tunnel GRE Tunnel RLP Links

Audio RTP

Video RTP

Audio RTCP

Video RTCPSIP

Audio RTP

Video RTP

Audio RTCP

Video RTCPSIP

IP Network

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PSVT QoS-2• PDSN enforces DiffServ code points• End-to-End QoS possible within managed network• (REDRAW figure)

DSCP

Application QoS Negotiation (SIP/SDP)

Air link (RLP)

A10 connection

SendingTerminal

Air link (RLP)

A10 connection

ReceivingTerminal

DiffServNetwork

DSCP

PDSN polices/remarks DSCP

then forwards IP packet

BSC/AN tunnels data over A10

connection

PDSN uses TFT filter to map

packet to A10

BSC/AN maps A10 to RLP link

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PSVT Issues

• Low-interruption handoffs– Procedures for inter-PDSN handoffs may not be

practical– HRPD does not YET support active handoffs

• Hand-down and hand-up– Variations in QoS resources or bearer support due to

sector loading or inter-technology handoffs– How to modify media streams (e.g., add/remove

video) with minimal interruption?– Updating QoS resources for MS

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LMSD Evolution

• Legacy Mobile Station Domain (LMSD)– IS-2000 RAN, with IP-based A–interface , VoIP transport

between MSC soft-switches

• Step 1, call delivery• Step 2, handoffs and better feature support.• Ability to interwork with other network types:

– MMD/IMS– Packet Cable– DSL

• Enhancements– Faster call setup – Security for bearer.

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Transition Architecture

• Evolution to MMD will occur in steps

• Transition architecture will support– Interworking with legacy circuit switched

networks– Handoffs from MMD services to legacy

services where possible.

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• Placeholder for HRPD/1x interworking figure

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MMD Evolution• Define the path from circuit switched voice networks to LMSD and

MMD• Transition Architecture

– Call delivery– Handoff– WLAN…..

• Services– VoIP/Push to Talk– Video Telephony– Conferencing– Messaging– Emergency services– Local services.

• Enhancements– Faster session setup– Security.

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Future Development

• True End-to-End QoS

• Full interworking with other networks, including 3GPP, internet, NGN.

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3GPP2 MMD Roadmap

• Architecture, Security, LMSD• Stage 2• Stage 3• Access network specifications.

(note – published documents available at www.3gpp2.org)

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Architecture, Security, LMSD

• Stage 1 and Overview Documents– S.R0037-A, IP Network Architecture Model for cdma2000 Spread

Spectrum Systems– S.R0062, Presence Stage 1– X.S0027-001, Presence Architecture– X.S0013-000, MMD Overview document

• Security Documents– S.R0086-A, MMD Security Framework

• Legacy Mobile Station Domain (LMSD) Documents– (IS-95/2000 circuit mode MS+RAN with VoIP core network)– S.R0092, System requirements– S.R0096 Transcoder Free Operation, Stage 1 requirements– P.S0002, LMSD - Step 1, incoming PSTN call delivery– X.S0012, MSCe-MSCe Signaling Control– X.S0018, G.711 PCM voice between MGWs.

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Stage 2

• X.S0013-002 IP Multimedia Subsystem (IMS) (based on 3GPP TS 23.228)

• X.S0013-003 IP Multimedia (IM) session handling; IM call model (based on 3GPP TS 23.218)

• X.S0013-007 Accounting  Architecture (based on TS 32.200)

• X.S0013-005 IP Multimedia (IM) Subsystem Cx Interface; Signaling flows and message contents (based on TS 29.228)

• X.S0013-010 IP Multimedia Subsystem (IMS) Sh Interface signaling flows and message contents (based on TS 29.328)

• X.S0017 Open Service Access (OSA); Application Programming Interface (based on TS 29.198 series)

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Stage 3

• Protocol & Procedures– X.S0013-004, IP Multimedia Call Control Protocol

based on SIP and SDP; (based on TS 24.229)– X.S0013-006, Cx Interface (HSS-CSCF) based on

the Diameter protocol; Protocol details (based on TS 29.229)

– X.S0013-008, Accounting data description (based on TS 32.225)

– X.S0013-011, Sh interface (HSS-AS) based on the Diameter protocol (based on TS 29.329.)

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CDMA Access Network Documents

• Packet Data Serving Node (PDSN)– X.S0011-C, Wireless IP Network Standard (IS-835)

• CDMA2000 1x air interface– C.S0001 to C.S0006, cdma2000 Family of Standards for

Spread Spectrum Systems– C.S0047, Header compression/removal service options, allows

VoIP to be sent efficiently over the air • CDMA2000 DO air interface

– C.S0024-A (IS-856-A), Significant upgrades for supporting QoS sensitive services

– C.S0063 (TIA-1054), Enhanced Multi-flow Packet Application, eliminates overhead from PPP and octet-based HDLC-like framing. Two-route RLP facilitates seamless BSC-BSC Connected State handoff to eliminate interruption during the VoIP call.

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Current Projects

• X.P0011-D, includes MIP6 and QoS support• X.P00xx, End-to-end QoS • X.S0013 revision

– Includes new part for Service Based Bearer Control, X.P0013-012, enables mapping/control of SDP-negotiated QoS to air interface QoS.

• X.P0027, New parts for presence security, protocol, network presence.• X.P0028, CDMA/WLAN interworking

– Scenarios 1,2– Scenarios 3,4

• X.P0029, Conferencing• TSB-58-G, to define QoS Profiles • A-interface

– IS-878-A/IS-1878-A, QoS support on the A-interface– IS-878-B / IS-1878-B, Connected State seamless inter-BSC soft handoff and session

transfer• C.P0023-C, R-UIM cards support for MMD data.• PN-0196, Lawfully Authorized Electronic Surveillance for cdma2000 VoIP.• HRPD/1x interworking• Packet Switched Video Telephony.