Palpatine: a P2PM IMS Video Share Architecture and Implementation Second International Conference and Exhibition on Next Generations Mobile Applications Services and Technologies. Cardiff, September Luis López Fernández, Micael Gallego. Universidad Rey Juan Carlos José M. Recio, F.Javier López. Solaiemes S.L.

What is this all about?

What is that IMS stuff about? IMS: IP Multimedia Subsystem An architecture for multimedia content delivery over IP networks

The Internet Jungle for multimedia communications before IMS

The Internet Jungle for multimedia communications after IMS IMS

What makes IMS different? IMS has been developped by the telecom industry for the telecom industry Why another architecture? Open Standards (IETF protocols) Many horizontal problems are simplified by the IMS architecture (security, billing, provisioning, etc.) Many mobile devices come with build-in IMS support without requiring additional customization Advantages Complexity Drawbacks

The IMS architecture

IMS seen from the perspective of the IMS service developper IMS Core Network Application Server SIP Media (RTP) SIP

Palpatine is an IMS Application Server IMS Core Network Application Server SIP Media (RTP) SIP Palpatine is here within the IMS structure

What is this Video Share stuff about? Video Share: a standardized IMS service for video exchange. GSM Association. Official Document SE.41

Video Share service definition Enrich an already established voice call Allows capture and stream video (near real-time) Allows stream recorded video

Video Share service description

Video Share service philosophy In one word: simplicity No complex voice-video-synchronization Point-to-point = UA-to-UA No IMS Application Server required Not even IMS infrastructure required (just a SIP registrar is enough)

Video Share P2P philosophy example

Current Video Share service Is able to Have similar applications to Video Call (i.e. almost none) Be available from factory setting in many mobile phones Is NOT able to Provide flexible services for professional applications – Video storage and recovery – Video distribution to a group – Channel switching Integrate seamlessly into current Internet infrastructure – Web 2.0 – Video portals (Qik, etc.) – Etc.

Steps for enritching current Video Share service deffinition GSMA shows us the way to go …

What is this P2PM stuff about? P2MP: Point-to-MultiPoint

P2P Vs P2MP Video Share Point-to-point One video source one video sink Point-to-multipoint One video source, several video sinks

Implementation restrictions for the P2MP Video Share service Maintain GSMA SE.41 backward compatibility Do not touch mobile terminals!! Do not touch network infrastructure!!

Palpatine AS P2MP without modifying UEs. Step 1: signaling Session initiating UA Session accepting UA Behaves like a session accepting UA Behaves like a session accepting UA Behaves like a session initiating UA Behaves like a session initiating UA The AS makes believe the UA that it is talking to another UA This configuration of the AS is called in the IMS jargon B2BUA: Back-to-Back User Agent

B2BUA AS in action

P2MP without modifying UEs. Step 2: media Media source UA Session accepting UA The AS makes transcoding, cloning and routing of the media streams Palpatine AS Behaves like a media sink UA Behaves like a media sink UA Behaves like a media source UA Behaves like a media source UA TX

What is that architecture?

Palpatine architecture Media Core Signaling Plane B2BUA Signaling Plane B2BUA CS Gateway IMS Layer External Control Module External Control Module Palpatine Core Logic CS Gateway SIP signaling CS audio RTP Video RTP audio RTP Video + Audio RTP audio CS audio

Palpatine architecture Media Core Signaling Plane B2BUA Signaling Plane B2BUA CS Gateway IMS Layer External Control Module External Control Module Palpatine Core Logic CS Gateway SIP signaling CS audio RTP Video RTP audio RTP Video + Audio RTP audio CS audio Palpatine Core Logic Signaling Plane B2BUA Signaling Plane B2BUA SIPUA Config DB Config DB Call-in Context Call-in Context Call-out Context Call-out Context Call-out Context Call-out Context Call-out Context Call-out Context SIPUA Palpatine Core Logic Config DB Config DB Call-in Context Call-in Context Call-out Context Call-out Context Call-out Context Call-out Context Call-out Context Call-out Context Media core RTP rec Mixer Cloner Commute r Transcoder RTP send

Palpatine architecture Media Core Signaling Plane B2BUA Signaling Plane B2BUA CS Gateway IMS Layer External Control Module External Control Module Palpatine Core Logic CS Gateway SIP signaling CS audio RTP Video RTP audio RTP Video + Audio RTP audio CS audio

External control module explained CS Gateway External Control Module External Control Module IVR With voice Recognition IVR With voice Recognition CS audio RTP Video RTP Video + Audio Control CS audio Media core RTP Video

But, did you really implement it?

Yes, we did

Questions? Don’t ask me why we called it Palpatine It wasn’t my idea