1 / 19

PTLIU Laboratory for Community Grids Geoffrey Fox, Wenjun Wu, Ahmet Uyar, Hasan Bulut

CTS04 San Diego 19 January 2004. Design and Implementation of Audio/Video Collaboration System Based on Publish/subscribe Event Middleware. PTLIU Laboratory for Community Grids Geoffrey Fox, Wenjun Wu, Ahmet Uyar, Hasan Bulut Computer Science Department

ndenton
Télécharger la présentation

PTLIU Laboratory for Community Grids Geoffrey Fox, Wenjun Wu, Ahmet Uyar, Hasan Bulut

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. CTS04 San Diego 19 January 2004 Design and Implementation of Audio/Video Collaboration SystemBased on Publish/subscribe Event Middleware PTLIU Laboratory for Community Grids Geoffrey Fox, Wenjun Wu, Ahmet Uyar, Hasan Bulut Computer Science Department Indiana University, Bloomington IN 47404 http://www.globalmmcs.org gcf@indiana.edu uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  2. A/V Collaboration Systems • H323 H.323 is defined as an umbrella standard specifying the components to be used within an H.323-based environment. • SIP The Session Initiation Protocol (SIP) defines how to establish, maintain and terminate Internet sessions including multimedia conferences • Access Grid enhanced Mbone A/V tools ( VIC, RAT ) Internet 2 network ( Multicast support ) uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  3. XGSP Collaboration Framework • To integrate heterogeneous systems into one collaboration system • A unified, scalable, robust “overlay” network is needed to support A/V and data group communication over heterogeneous networking environments. • A common A/V signaling protocol has to be designed to support interactions between different A/V collaboration endpoints. • Different A/V endpoints should collaborate in the same collaboration session. uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  4. Group Communication in Collaboration • Collaboration applications usually need a group communication service for both multipoint data and control information delivery • Centralized conferencing systems usually depend upon a single conference server • Distributed conferencing systems use IP multicast Access Grid uses Internet2 multicast for audio/video transmission. • Problems: Centralized conferencing systems don’t have good scalability IP multicast has not become ubiquitously available uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  5. Data base Narada Broker Network (P2P) Community For message/events service Broker Broker (P2P) Community Resource Broker Broker Broker (P2P) Community Software multicast Broker (P2P) Community uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  6. Narada Brokering • Narada Brokering from the Community Grid Labs is adopted as a general event brokering middleware • supports publish-subscribe messaging model with a dynamic collection of brokers • provides services for TCP, UDP, Multicast, SSL and raw RTP clients • Supports the communication through firewalls and proxies • operate either in a client-server mode like JMS or in a completely distributed JXTA-like peer-to-peer mode. uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  7. Narada Brokering • Covers the heterogeneity of network transportation and provides unified multipoint transportation API • Software multicast • Communication over firewalls and proxy boundaries • Communication over multiple transports • Application level Quality of Service • Filter messages to slow (collaborative/real-time) clients • Provides robust, scalable and high efficient multipoint transportation services • Availability and scalability • Efficient routing and bandwidth utilizations uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  8. A/V Collaboration over publish/subscribe Middleware • video streams (VS) VS {v1, v2, … vm } • audio streams (AS) AS { a1, a2, … an } • A/V endpoints: E1, E2, … En Each endpoint may send a single or multiple video streams, but only send an audio stream • Different types of A/V endpoints have different collaboration capabilities. • Multicast endpoints are able to receive multiple video and audio streams, display all the video streams in their screens, and mix all the audio streams by themselves • Unicast endpoints like Polycom Via Video can only receive and play a single video and audio stream uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  9. Publish/subscribe of A/V • A stream in VS and AS is regarded as a “topic” • Each RTP packet from this stream is regarded as an “event” for this topic • Only the sender of this stream can “publish” A/V events to this topic • Other endpoints need to subscribe to this topic in order to receive the stream data • Create mixed video and audio stream topics for unicast endpoints uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  10. Major Events for each stream topic uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  11. A/V Collaboration Architecture uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  12. RTP packets encapsulation • RTPLink: RTP Packets ~ Narada Brokering Event • Every legacy A/V client needs one corresponding RTPLink to be set up at a broker within broker network. • Unicast RTPLink: Integer Topic Numbers for RTP and RTCP • Multicast RTPLink: A reflector between NaradaBrokers and multicast groups, encapsulating raw RTP packets from a multicast IP address to RTP events, publishing these events to NaradaBrokers, and forwarding the data it receives from broker network on the same IP address uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  13. Audio Mixer, Video Mixer, Image Grabber • Audio Mixing The audio mixer creates a mixed audio stream from all the audio streams in the session • Video Mixing Video mixing makes the unicast users watch the pictures of multiple participants in a meeting through one video stream • Video Thumbnail visualize the VS set in the session, embedded into the control panel of each endpoint, which Image grabbers capture video streams and save them as static JPEG files. • All the media processing components can be distributed among the pool of the media servers connected to NaradaBrokering infrastructures. uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  14. H.323, SIP Gateway Servers, A/V Session Server • H.323 and SIP gateway transform these protocol specific messages into XGSP signaling messages so that H.323 and SIP A/V endpoints could communicate with the XGSP A/V session server • The session server implements session management logics • creating/destroying A/V sessions • allowing endpoints to join/leave session • Allowing users to make audio/video selection, managing A/V application components uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  15. Implementation • Java Media Framework (JMF) : • Openh323 is basis of H323 Gateway • NIST SIP stack is basis of SIP Gateway • NaradaBrokering is open source messaging from Indiana uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  16. Demo Pics ( I ) uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  17. Demo Pics ( II ) uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  18. Demo Pics ( III ) uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

  19. Thank you! Please watch our demo at 5:30 PM ! uri="http://www.globalmmcs.org" email="gcf@indiana.edu"

More Related