Transcript Palpatine

Palpatine: a P2PM IMS Video Share
Architecture and Implementation
Second International Conference and Exhibition on
Next Generations Mobile Applications Services and Technologies.
Cardiff, September 2008.
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?
Why another architecture?
• IMS has been developped by the telecom industry for the telecom industry
Advantages
• 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
Drawbacks
• Complexity
The IMS architecture
IMS seen from the perspective of the
IMS service developper
SIP
IMS
Core Network
SIP
Application
Server
Media (RTP)
Media (RTP)
Palpatine is an IMS Application Server
Palpatine is
here within the
IMS structure
SIP
IMS
Core Network
SIP
Application
Server
Media (RTP)
Media (RTP)
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
Is NOT able to
• Have similar applications to
Video Call (i.e. almost none)
• Be available from factory
setting in many mobile
phones
• 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.
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!!
P2MP without modifying UEs.
Step 1: signaling
Palpatine AS
Session
initiating UA
Behaves like
a session
accepting UA
Behaves like
a session
initiating UA
Session
accepting 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
Palpatine AS
Media
source UA
Behaves like
a media
source UA
Behaves like
a media
sink UA
Session
accepting UA
TX
The AS makes transcoding, cloning and routing of the media streams
What is that architecture?
Palpatine architecture
External
Control Module
IMS
Layer
SIP signaling
Signaling Plane
B2BUA
IMS
Layer
SIP signaling
Palpatine Core
Logic
RTP Video
CS audio
CS
Gateway
RTP
audio
RTP Video + Audio
Media Core
RTP
audio
CS
Gateway
CS audio
Signaling Plane
B2BUA
Palpatine architecture
SIPUA
SIPUA
SIPUA
SIPUA
External
Control Module
IMS
Layer
IMS
Layer
Palpatine Core Logic
SIP signaling
SIP signaling Palpatine Core Logic Call-out
Signaling Plane
Config
Context Call-out
B2BUA
Context
Call-in
Call-out
DB
Context
Call-out
Config
Context Call-out
Context
Context
Call-in
DB
Palpatine Core
Context
Call-out
Logic
Context
RTP Video
CS audio
CS
RTP rec Gateway
Mixer
RTP rec
Media core RTP Video + Audio
RTP
audio
Media Core
Cloner
RTP Transcoder
CS
audio
Gateway
Commute
r
RTP send
CS audio
Transcoder
RTP send
Transcoder
RTP send
Palpatine architecture
External
Control Module
IMS
Layer
SIP signaling
Signaling Plane
B2BUA
IMS
Layer
SIP signaling
Palpatine Core
Logic
RTP Video
CS audio
CS
Gateway
RTP
audio
RTP Video + Audio
Media Core
RTP
audio
CS
Gateway
CS audio
External control module explained
External
Control Module
IVR
Control
CS audio
With voice
Recognition
RTP Video
RTP Video
RTP Video + Audio
RTP Video
CS audio
CS
Gateway
Media core
But, did you really implement it?
Yes, we did
Questions?
• Don’t ask me why we called it Palpatine
• It wasn’t my idea