1 / 16

IP Multicast Applications: Challenges & Solutions

IP Multicast Applications: Challenges & Solutions. Bob Quinn Stardust Forums, Inc. IP Multicast Initiative. Agenda. ID Motivation & Purpose ID Scope Multicast Application Taxonomy Primary Requirement Challenges Heterogeneous Receivers Reliable Delivery Secure Multicast.

ivor-joyner
Télécharger la présentation

IP Multicast Applications: Challenges & Solutions

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. IP Multicast Applications:Challenges & Solutions Bob QuinnStardust Forums, Inc.IP Multicast Initiative

  2. Agenda • ID Motivation & Purpose • ID Scope • Multicast Application Taxonomy • Primary Requirement Challenges • Heterogeneous Receivers • Reliable Delivery • Secure Multicast

  3. Motivation for the Internet Draft IP Multicast Initiative - ipmulticast.com • What:Multi-vendor Forum • Members are International and Cross-Industry • Why: Promote adoption of IP Multicast • Overcome the Chicken-and-Egg problem • How: Education • Evangelize its benefits, and describe its details • Publish documentation and Host events • Informational Internet Draft...

  4. Purpose of the Internet Draft • Informational • <draft-quinn-multicast-apps-00.txt> • A Roadmap for Application Developers • An Orientation Tool • “You are here...” in terms of • Application Type • Application Requirements • “Here’s where to go now...”

  5. Ultimate Goal of Internet Draft • Help Application Developers to Avoid: • Reinventing Wheels • Spinning Wheels • Running Roughshod over IP Networks • encourage “network-friendly” application designs • “heads-up” when “you can’t get there from here”

  6. Scope of Internet Draft • Focus is on Applications • not Infrastructure or Mechanics • Assumption: Multicast-Enabled Network: • Already Exists • Transparent to Applications • Assumption: Developer aware of mechanics • Refer to Maufer/Semeria ID for details<draft-ietf-mboned-intro-multicast-03.txt>

  7. Multicast Application Taxonomy • Sender/Receiver Relationships • Differentiate Multicast from Unicast • Characterize all Multicast Applications • All Multicast Apps are one of Three Types: • One-to-Many • Many-to-Many • Many-to-One

  8. One-to-Many Applications • Analogous to the TV/Radio Broadcast Model • Useful and valid analogy, but not all there is... • Push Media: headlines, weather, sports... • File Distribution and Caching • Announcements: network time, session schedules, randoms, keys... • Monitoring: stock prices, sensors, security, manufacturing...

  9. Many-to-Many Applications • Multimedia Conferencing: A/V and whiteboard • Synchronized Resources: Database updates... • Concurrent Processing: Distributed & Parallel • Shared Editing and Collaboration • Interactive Distance Learning • Distributed Interactive Simulations (DIS) • Multi-Player Gaming, Chat Groups • Jam Sessions

  10. Many-to-One Applications • Many are request/response... • Resource Discovery: Service Location, Anycast • Data Collection • Auctions • Polling • Juke Box

  11. Multicast App Requirements • Bandwidth, Delay and Jitter • Multicast Apps are no different from Unicast • Useful to characterize needs nonetheless... • Multicast is a Special Case when Servicing: • Heterogeneous Receivers • Reliable Data Delivery • Security

  12. Heterogeneous Receivers • Adapting to receiver rates, delays and jitter • Difficult with unicast, but worse with multicast • Strategies and Challenges: • Feedback loops - Danger of implosions • Forward Error Correction - Uses bandwidth • Shared Learning - Privacy Issues • Local Recovery - Management Issues • No standards yet. Research effort informal.

  13. Reliable Data Delivery • Receivers tolerant of delay, but not loss • TCP model doesn’t translate (implosion) • Strategies and Challenges: • NAKs - implosion potential still exists • FEC, Shared Learning, and Local Recovery are all also relevant • No standards yet. • RMRG in IRTF is defining the problem

  14. Multicast Security • Receivers and Senders are wary • Don’t trust data, or each other, or anyone else • Unicast is hard, and multicast is HARDER • Challenges: authentication and key distribution • Strategies: many and varied • No standards yet. • SMuG in IRTF is defining the problem

  15. Observations • Three Primary Requirements share many of the same Strategies & Challenges • Common issue is dealing with asymmetry in the sender/receiver relationship • e.g., Local Recovery - smarts in the net • Solutions may have cascade effect (?) • Prevailing Consensus: we need more than one protocol to satisfy the varying application requirements in each category

  16. Evaluation • Is this of value? • Should this be a draft from MBoneD WG?? • Any Questions? Comments? Suggestions? • Send to <rcq@stardust.com> & mboned mail-list • Also see http://www.ipmulticast.com

More Related