1 mmd evolution june 28, 2005. 2 outline mmd basics end-to-end example –packet switched video...
TRANSCRIPT
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MMD Evolution
June 28, 2005
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Outline
• MMD Basics
• End-to-End Example– Packet Switched Video Telephony
• Transition to MMD
• Legacy MS Domain Evolution
• 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
• MMD 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 IMS. Now nearly identical at IMS level.
• Regulatory issues are being addressed – (VoIP surveillance, tax structure for internet services, emergency calling
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
2
3
3 Apply Service Logic
Retrieve Address of Called Party Home Networkand Forward INVITE.
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4
Identify Registrar of Called 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 Called 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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IMS call flow
RTP Stream
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12 Session Active
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Packet Switched Video Telephony (PSVT)
• 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– A.S0011~17-C IOS– C.S0024 HRPD Rev A– C.S0001~6 CDMA2000.
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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
MRFP(optional)
MRFC(optional)
AAA
HSS
P-CSCF
AAA
HSS
P-CSCF
AS(optional)
SIP SignalingAir Interface/IOS SignalingMedia Control for Audio/VideoPSVT /VoIP Audio Bearer PathPSVT Video Bearer PathAAA/HSS InterfacesMP Interfaces
AS(optional)
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PSVT Call Flow S-CSCFP-CSCFPDSNRANMS-1
8. MediaFlow
1. SIP Capability Exchange (INVITE/183)
2. Bearer Resource Establishment Completed
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 Completed
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PSVT QoS-1• Access networks (PDSN) enforce agreed QoS
for different IP flows• PDSN enforces DiffServ code points• End-to-End QoS within managed network
SIPServers
Terminal RAN PDSN PDSN RAN 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
Indicates that theencircled flows are giventhe same QoS treatment
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PSVT QoS-2
Air Link (RLP)
A10 connection
DSCPDSCP
A10 connection
Air Link (RLP)
SendingTerminal
ReceivingTerminalRAN PDSN PDSN RAN
DiffServNetwork
RAN maps theAir Link to the
A10 connection
PDSN polices/remarks DSCP
then forwards IPpacket
PDSN uses TFTfilter to map
packet to A10connetion
RAN maps A10to Air Link
Application QoS Negotiation (SIP/SDP)
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PSVT Challenges
• Low-interruption handoffs– Requires low latency inter-PDSN handoffs – 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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Transition Architecture
• Evolution to MMD in steps
• Transition architecture will support– Interworking with legacy circuit switched
networks– Handoffs from MMD services to legacy
services where possible; for example VoIP on HRPD handoff to 1x voice services.
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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 calling features support• Ability to interwork with other network types:
– MMD/IMS– Packet Cable– DSL
• Enhancements– Faster call setup – Security for bearer.
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MMD Evolution• Path from circuit switched voice networks to LMSD and MMD• Transition Architecture
– Call delivery– Handoff– WLAN interworking
• Services– Conferencing– Messaging and Presence– Emergency services– Local services
• Enhancements– SIP optimization, faster session setup– Security improvements– (true?) End-to-End QoS
• Convergence and interworking with other networks, including UMTS/IMS, public Internet, Next Generation Networks.
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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.S0027-000, Presence Overview – 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.S0027-001, Presence Architecture
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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.)
– X.S0017 Open Service Access (OSA); Application Programming Interface (based on TS 29.198 series)
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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.S0013 revisions, with new parts for
– Service Based Bearer Control, enables mapping/control of SDP-negotiated QoS to air interface QoS
– On-line charging– SIP optimization
• 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• End-to-end QoS • Packet Switched Video Telephony.