1 / 15

Experimental evaluation of Moderated EDCA over WMP

Date: November 11, 2015. Experimental evaluation of Moderated EDCA over WMP. Authors:. Experiment Setup. 6 contending nodes under saturated greedy traffic two groups of stations: legacy EDCA and moderated EDCA (M-EDCA). Moderated EDCA. EDCA. AP. How to implemented M-EDCA?.

conboy
Download Presentation

Experimental evaluation of Moderated EDCA over WMP

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. Date: November 11, 2015 Experimental evaluation of Moderated EDCA over WMP Authors:

  2. Experiment Setup • 6 contending nodes under saturated greedy traffic • two groups of stations: legacy EDCA and moderated EDCA (M-EDCA) Moderated EDCA EDCA AP

  3. How to implemented M-EDCA? • In principle a very ‘small’modification of the protocol, but working on lower-mac parameters.. • How to measure backoff freezing occurrences, being backoff process hard-coded into the card? • Feasible thanks to the Wireless MAC Processor (WMP) architecture! • Developed by the CNIT research team within the European research project FLAVIA

  4. MAC design: XFSM WMP Architecture • In one slide… • Set of radio tasks pre-implemented in the NIC • actions, events, conditions • In practice, a MAC-specific «instruction set» • MAC programs: eXtended Finite State Machines • Suitably byte-coded for injection in the NIC • NIC: no more a protocol, but an XFSM executor • Called «wireless MAC processor» bytecode MAC Engine: XFSM executor load MAC Bytecode

  5. From EDCA to M-EDCA(basically, adding a transition for counting IPT!) RX PHASE TX PHASE BACKOFF

  6. CW Updates • Periodic CW updates in Userspace (for using floating-point arithmetic): • Sample IPT at regular time intervals and update CW • CW update acts directly on NIC registers. • State machine at firmware level: • Measure IPTm • Filter IPT = IPT + 1/8 * (IPTm -IPT); T USERSPACE SCRIPT CW update DATA REQUEST WMP REGISTER FIRMWARE

  7. Results • Reference experiment: 6 EDCA legacy nodes • Throughput variability from 0.6 to 1.6 Mbps due to real position-dependent interference • Average CW from 21.58 to 29.24 6 EDCA EDCA CW

  8. Results • 3 EDCA legacy nodes vs. 3 Moderated EDCA • Throughput results comparable with previous ones! • lower variability for M-EDCA stations • Average CW for Moderated EDCA equal to 22 (vs. 24 obtained in simulation) • Damping factor selected 0.7 and 0.1 • Moderated CWs updated every 100ms • See plots on next slides

  9. Throughput (damping 0.7)

  10. Throughput (damping 0.1)

  11. EDCA CW (damping 0.7)

  12. EDCA CW (damping 0.1)

  13. Moderated EDCA CW (damping 0.7)

  14. Moderated EDCA CW (damping 0.1)

  15. References https://mentor.ieee.org/802.11/dcn/15/11-15-1152-01-000m-moderated-backoff.ppt

More Related