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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
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IMS and Media Control James Rafferty, Cantata Technology August 10, 2007
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 IMS focus for Media control: MRF
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
Timeline for Media Server Protocols Conference-Control Optimized Interface for SIP Environment RFC Editor Queue Multifunction Media Server Interface; SIP Paradigm Added Basic Media Services for Device Control Applications; No known applications Fixed MGCP Problems; Focus on Gateways; IETF Standard SIP/MSCML Utility for Media Server Attempt to Address Intellectual Integrity Issues SIP/netann Media Server Afterthought; Not IETF Standard H.248.1 SIP/MSML “All the Features of MGCP, But With SIP Transport” H.248 MGCP SIP/MOML-MSML Time 1999 2000 2001 2002 2003 2004
MRF ArchitectureComponents App Server ISC S - CSCF Mr (SIP) • Lots of discussion on best way to handle in 3GPP / IETF • Some implementers will combine MRFC/MRFP (MRF) MRFC Mp (H.248) MRFP
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 ITU-T
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
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 Another Possible Approach • Network Function Required • MRFC Capability Discovery • MRFC Allocation & Load Balancing • Consolidated CDR, OAM, Provisioning • Media Resource Function Broker (MRFB)
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
Unified Messaging Announcements Video Mail VideoConferencing SponsoredCalling Pre-Paid Voice Mail Conferencing Video Ringback Gaming IP MSC Win Media mp3 MGW Text CMTS S-CSCF / SCIM Putting the MRF to Work SIPMSCML 3G SIP SIPVoiceXML SIP IMG SIP Routing Cloud 2.5G IMG SIPSIP w/ VoiceXML SIP w/ MSCML SIP Web Content HTTP PSTN RTP FTP MPEG-4 MRF NFS Cable IP Phones (MRFC/MRFP) 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 Ubiquity SIP AS Gaming Data Gaming Data WiFi Cantata MRF Terraplay Game Qualphone Client CDMA Mobile Call MGW-IMG PLMN NexTone CSCF Outbound T1 PRI BayPacket Prepaid CDMA Mobile Calls IBM Presence BayPackets Prepaid
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 Example: Sponsored Call Service
Case Study: Video Messaging Deployment 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. • Developed by OpenWave Service Features • 3G VideoMail • 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 • What are some examples of media within an MRF? • What are examples of “prior art” that are influencing the MRF? • 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