1 / 36

Bridges of Bluetooth Country: Topologies, Scheduling, and Performance

Bridges of Bluetooth Country: Topologies, Scheduling, and Performance. IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 21, NO. 2, FEBRUARY 2003. Outline. Introduction Topologies and Scatternet Operation Performance of the MS Bridge Performance of the SS Bridge Analyses Conclusion.

sauda
Download Presentation

Bridges of Bluetooth Country: Topologies, Scheduling, and Performance

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. Bridges of Bluetooth Country: Topologies, Scheduling, and Performance IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS, VOL. 21, NO. 2, FEBRUARY 2003

  2. Outline • Introduction • Topologies and Scatternet Operation • Performance of the MS Bridge • Performance of the SS Bridge • Analyses • Conclusion

  3. Introduction(1) • Bluetooth • Cable replacement • Short range as hoc network • Piconet • TDD master-level communication

  4. Introduction(2)

  5. Topologies and Scatternet Operation(1) • MS Bridge Operation

  6. Topologies and Scatternet Operation(2)

  7. Topologies and Scatternet Operation(3) • SS Bridge Operation

  8. Topologies and Scatternet Operation(4)

  9. Topologies and Scatternet Operation(5)

  10. Topologies and Scatternet Operation(6) • Scheduling Policies • Under limited service scheduling • Poll slaves within a single frame sequentially • Regrardless of data transmission has taken place or not • Use Round-Robin to determine the next slave

  11. Topologies and Scatternet Operation(7) • Under exhaustive service scheduling • Master stays with one slave until there are no data to send to either way • Polls next slave sequentially when detects a POLL-NULL frame • Use Round-Robin to determine the next slave • Stochastically Largest queue (SLQ) • Optimal performance • Hard to implement

  12. Performance of the MS Bridge(1) • Access Delay Under Limited Service Scheduling • The burstier the traffic, the longer the access delay • It is useful in the design of packet segmentation policy

  13. Performance of the MS Bridge(2) • End-to-End Delay Under Limited Service Scheduling • In the same piconet

  14. Performance of the MS Bridge(3) • End-to-End Delay Under Limited Service Scheduling • Go through the bridge

  15. Analysis and Simulation Results(1)

  16. Analysis and Simulation Results(2) • As predicted, an increase in mean burst length corresponds to a nearly linear increase in all delay variables • Small delay could be achieved by keeping the burst length as small as possible • Packet segmentation is another topic currently missing from the Bluetooth specification

  17. Analysis and Simulation Results(3)

  18. Analysis and Simulation Results(4)

  19. Analysis and Simulation Results(5)

  20. Analysis and Simulation Results(6)

  21. Analysis and Simulation Results(7)

  22. Performance of the SS Bridge(1)

  23. Performance of the SS Bridge(2)

  24. Analysis and Simulation Result(1) SS bridge over limited service scheduling

  25. Analysis and Simulation Result(2) SS bridge over exhaustive service scheduling

  26. Analysis and Simulation Result(3) Mean access delay

  27. Analysis and Simulation Result(4) Mean end-to-end delay

  28. Analysis and Simulation Result(5) Mean end-to-end delay for non-local traffic

  29. Analysis and Simulation Result(6)

  30. Conclusion(1) • Increases of delay times may be cause by the following condition: • High-burst arrival rates • Low probability of local traffic • Short intervals between bridge exchange

  31. Conclusion(2) • Regardless of the topology and/or scheduling policy, delays are not too sensitive on T1 • The T1 time interval should not be to small, and value in the range over 40 to 60T should give satisfactory results

  32. Conclusion(3) • Mean access delay is lower in the scatternet topology with an SS bridge • Because both piconet masters can spend more time servicing their slaves in their respective piconets • Mean end-to-end delay for nonlocal traffic is lower with an MS bridge • Due to the low number of hops

  33. Conclusion(4) • MS bridge is more sensitive to the combination of • High-packet burst arrival rate • Low traffic locality • Too short time interval between bridge exchange • But not likely to be encountered in practice

  34. Conclusion(5) • Exhaustive service scheduling outperform limited service scheduling, sometimes as much as 30% • The difference get smaller when burst arrival increases • Reason: under low loads, limited service scheduling will “waste” slots

  35. Conclusion(6) • But, exhaustive service scheduling does not guarantee fairness • An acceptable tradeoff: K-limited service • Which can still providing a sufficient degree of fairness

  36. Future work • The operation of Bluetooth scatternets should be analyzed from the viewpoint of higher layers of the protocol stack • IP over Bluetooth • Policies for packet segmentation and reassembly

More Related