1. Better-Behaved Multimedia Networking Keith Barber Jason Ingalsbe Joel Thibault Prof. Mark Claypool (Advisor) April 19, 2001

2. Issues with Multimedia Traffic Basic Internet protocols inappropriate for multimedia –TCP does not provide smooth transmission –UDP takes up too much bandwidth Multimedia protocols must be TCP-friendly

3. Existing Alternatives TCP-Friendly Rate Control (TFRC) TCP Emulation At Receivers (TEAR) MM-Flow

4. Re-Engineering MM-Flow Location of flow control logic –“True” application and transport layers –Receiver decides whether scale value should change –Sender converts scale values to transmission rate Number of scale values Weighted average scale

5. Evaluation Techniques Simulation Scenarios –Standard Bottleneck Layout –Standard Delay Layout –Standard Fragile Layout

6. Standard Bottleneck Layout

7. Standard Delay Layout

8. Standard Fragile Layout

9. Effects of Re-Engineering MM-Flow Responsiveness to Congestion Fair Share of Bandwidth Relative Smoothness

10. MM-App-Old vs. TCP

11. MM-App-New vs. TCP

12. Further Evaluation of MM-App-New Packet Size Number of Scale Values Delay Fragile Flows Weighted Scale Values

13. TCP-Friendly Flows Possible definitions: –Flow uses fair share of bandwidth –Flow responds to congestion –Flow transmission rate less than or equal to TCP flow transmission rate Quantitative measurement is desired

14. TCP-Friendly Equation Implications and Assumptions: –Packet Drop Rate –Measurement Interval Size

15. TCP-Friendly Results (1 sec.)

16. TCP-Friendly Results (3 sec.)

17. TCP-Friendliness of MM-App-New

18. TCP-Friendliness of TFRC

19. Multi-Protocol Layout

20. Multi-Protocol Env. (TCP)

21. Multi-Protocol Env. (TFRC)

22. Multi-Protocol Env. (MM-App-New)

23. Conclusion and Future Work MM-Flow is an improvement over original Areas for future research: –Increase transmission rate quickly at startup –Decrease fluctuation in transmission rate –Continue examination of TCP-Friendliness

24. Questions? http://www.wpi.edu/~jmi725/mqp http://perform.wpi.edu