Transcript Document

IMS and Media Control
James Rafferty, Cantata Technology
August 10, 2007
IMS and Media Control
IMS and Media Control
• Relationship to Overall IMS
• Media Resource Function
–
–
–
–
Prior Art
Relationship to Application Servers
MRFC
MRFD
• MRF Interfaces
• Putting the MRF to Work
• Application Examples
The IMS Architecture
IP Multimedia Networks
Legacy mobile
signalling Networks
CS Network
Mm
Mb
Mb
CS
BGCF
IMS focus
for Media
control:
MRF
AS
Mm
CS
Mk
Mk
ISC
Mw
Mj
Sh
Cx
C, D,
Gc, Gr
BGCF
Mi
Cx
IMMGW
MGCF
Mc
MRFP
MRFC
Mp
Mb
Mb
HSS
S-CSCF
Mg
Mr
Mb
Mb
I-CSCF
Dx
SLF
Mw
Dx
P-CSCF
UE
Gm
Ut
IMS Subsystem
3GPP TS 23.228 V7.2.0 (2005-12)
Media Resource Function
• 3GPP has borrowed the MRF concept
from several sources
• Basic idea of MRF or Media Server is to
service the media needs of applications
– Collect Digits, Process tones, voice
play/record, video play/record, …
MRF Prior Art
• MRF concepts derived from several
predecessors
– Concept of Decomposed architecture came from
Softswitch Movement (ISC, ITU, IETF)
– Concept of SIP for Media Server control begun by
Snowshore and validated by IPCC Reference
Architecture
– Several companies have been working with SIP
plus XML based markup languages for Media
Control over last few years
• Several variants including Netann (RFC 4240),
VoiceXML, MSCML, MSML/MOML
Utility for Media Server
Timeline for Media Server Protocols
Conference-Control
Optimized Interface
for SIP Environment
RFC Editor Queue
Multifunction
Media Server
Interface; SIP
Paradigm
Fixed MGCP
Problems; Focus on
Gateways; IETF
Standard
Added Basic Media
Services for Device
Control Applications;
No known applications
SIP/MSCML
Attempt to
Address
Intellectual
Integrity Issues
SIP/netann
Media Server
Afterthought; Not
IETF Standard
H.248.1
SIP/MSML
H.248
MGCP
1999
2000
2001
“All the Features of
MGCP, But With SIP
Transport”
2002
2003
SIP/MOMLMSML
2004
Time
MRF Architecture
Components
ISC
App Server
S - CSCF
Mr (SIP)
MRFC
Mp (H.248)
MRFP
• Lots of discussion on
best way to handle in
3GPP / IETF
• Some implementers
will combine
MRFC/MRFP (MRF)
MRFC
• MRFC = Multimedia Resource Function
Controller
• Definition:
– MRFC can accept SIP Invites requesting
tones and announcements, ad-hoc
conferences and transcoding
– Works with MRFP on carrying out media
operations if not a combined MRFC/MRFP
MRFP
• MRFP = Multimedia Resource Function
Controller
• Definition:
–
Provides resources to be controlled by the
MRFC
– Mixes incoming media streams (e.g. for multiple
parties).
– Sources media streams (for multimedia
announcements).
– Processes media streams (e.g. media analysis).
Related Interfaces
• Mr (S-CSCF – MRFC) interface
– Based on SIP
• Active work item in 3GPP; related work in IETF
• Mp (MRFC - MRFP) interface
– Based on H.248 (Megaco)
• Active work item in 3GPP; related work in ITUT
The Controversy
• Most robust media servers are controlled via
SIP
• 3GPP specified media interfaces only at high
level up until now
– SIP for Mr (to control MRFC)
– H.248 for Mp (to control MRFP)
• Many leading MS vendors strongly support a
SIP-only MRF
– However, 3GPP is moving ahead with H.248 as
the protocol for the Mp interface
Issues with MRFC/MRFP
Decomposition
• With no Media Processing Experience
– Belief Was MRFC:MGC::MRFP:MG
– Lots of Media Resources Controlled By Controller
• Separates Media Control (“Control Plane”)
From Media Processing (“Media Plane”)
MGC
MRFC
MRFP
MRFP
MRFP
MRFP
What Is Today’s Reality?
• MRFC Capacity
– 600 Sessions/Box (VoiceXML)
– 1000 Sessions/Box (Trivial IVR, Basic Conferencing)
• MRFP Capacity
– Early Media Servers: 20,000 Sessions/Box
– Ratio MRFC:MRFP in deployment is at Least 20:1
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFP
Another Possible Approach
• Network Function Required
– MRFC Capability Discovery
– MRFC Allocation & Load Balancing
– Consolidated CDR, OAM, Provisioning
• Media Resource Function Broker (MRFB)
MRFB
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFC
MRFP
Potential MRFB Interfaces
• Clearly, MRFB Uses Mr (SIP) to S-CSCF
– Do Not Change S-CSCF
• Should MRFB use H.248 or SIP to MRFC?
– H.248 Would Change MRFC
– Creates many Technical Issues Raised Above
• MRFB Makes Collection of MRFC/MRFP
(MRF) Look Like Single Media Resource
Putting the MRF to Work
Unified
Messaging
Announcements
Video Mail
Video
Conferencing
Sponsored
Calling
Pre-Paid
Voice Mail
Conferencing
Video Ringback
Gaming
3G
SIP
IMG
2.5G
SIP
S-CSCF /
SCIM
IP MSC
SIP
MSCML
SIP
VoiceXML
SIP Routing Cloud
Win Media
mp3
IMG
PSTN
MGW
SIP
RTP
SIP
SIP
SIP
w/ VoiceXML
w/ MSCML
HTTP
Web Content
Text
FTP
MRF
Cable CMTS
IP
Phones
(MRFC/MRFP)
MPEG-4
NFS
Network
Storage
Example: IMS Network Gaming
Demo
• Developed with IBM and partners
–
–
–
–
Qualphone client on mobile handset
Uses “presence” for user availability
MRF provides conferencing (“trash talk”) and IVR
Terraplay “Lock n’ Load” Multi-player game
IMS Gaming Service Delivery
Gaming Data
Gaming Data
Cantata
MRF
Qualphone
Client
Ubiquity SIP
AS
Terraplay
Game
CDMA Mobile Call
MGW-IMG
NexTone
CSCF
PLMN
Outbound T1 PRI
BayPacket
CDMA Mobile Calls
Prepaid
BayPackets
Prepaid
IBM
Presence
Example: Sponsored Call Service
• Developed by ARGELA
Technologies
• “Sponsored Call”
– 3G subscriber views a
video commercial from a
“sponsor”
– Subscriber receives a
discount on service
• Rapid development
– 4 weeks from
development to trial
Benefits of Sponsored Call Service to…
Subscribers
Sponsors
Providers
• Saves $$
• Useful promotions
• Multimedia channel of
advertisements
• Interactive promotions, campaigns
and surveys
• Select the customer segments
• New revenue
stream from the
sponsors
• Increased air time
and revenue
Case Study: Video Messaging
Deployment
• Developed by
OpenWave
Service Features
• 3G VideoMail
Provider: TMN – With more than five
million subscribers in Portugal and a
total of 25 million accounts
worldwide, TMN is Portugal’s largest
mobile operator.
– Greeting
– Message drop-off
– Subscriber retrieval
• VoiceMail
Converged Application
• Access From PC Over
Broadband As Well As
Wireless
New video service deployed for
European Soccer Championship
Games in Portugal 2004
Other Likely IMS Applications
• FMC – Fixed Mobile Convergence
• IP Centrex Hosting for Businesses
• Audio and Video combined with other
services
– For example, conferencing, push-to-communicate,
Multimedia over Broadband, Multimedia IM
• Legacy Migration
– Voice mail, conferencing, SMS, Prepaid Services
Workshop Questions
1. What are some examples of media
within an MRF?
2. What are examples of “prior art” that
are influencing the MRF?
3. Which protocols are proposed to
control the following IMS elements?
•
•
MRFC
MRFP
Summary
• MRF is the Media Resource Function in the
IMS
• Strongly influenced by prior art in control of
Media Servers
• 3GPP is working on standards for MRF
control, with IETF and ITU
– Still much debate in standards bodies about
details
• Pre-IMS solutions using SIP and XML markup
are being deployed today