Alternate EDCA Parameter Set July 2009 doc.: IEEE 802.11-10/0048r2 Jan 2010 Alternate EDCA Parameter Set Date: 2010-01-15 Authors: Alex Ashley, NDS Ltd Alex Ashley, NDS Ltd

July 2009 doc.: IEEE 802.11-10/0048r2 Jan 2010 Abstract This proposal fulfils the PAR objective of the 11aa task group: Intra-Access Category prioritization of transport streams by modifying EDCA timing and parameter selection without any requirement for deep packet inspection This proposal allows the creation of up to 2 extra EDCA parameter sets to facilitate intra-access category prioritization. Alex Ashley, NDS Ltd Alex Ashley, NDS Ltd

Jan 2010 Use Cases Prioritize all packets in a video stream above/below another video stream In EDCA and EDCA-AC modes The higher priority video has a greater chance of channel access Alex Ashley, NDS Ltd

Jan 2010 Comments “There should be extra ACs or some other solution, but not per frame parameter changing. The backoff is a post-backoff which comes after the frame, not before it. Parameter changing makes no sense.” “How do the new AACs work? I see the two level queuing, so I'm expecting that there is a first round of internal contention say between AAC_VI and AC_VI … what parameters are used for over-the-air contention?” How do I know if a STA implements the extra EDCA timing parameters? Don’t we need to specify the scheduler for consistent performance? Alex Ashley, NDS Ltd

Changes from r0 proposal Jan 2010 Changes from r0 proposal Shorter Alternate EDCA Parameter Set AAC_BE and AAC_BK removed. AAC_VI / AAC_VO only included in element when supported Removed need for extra EDCAF Makes it possible to implement on existing h/w Removed requirement to use CL for AAC_VI Controlled Load (CL) has defined meaning in enterprise networks Added default EDCA parameters for AAC_VI and AAC_VO Same as AC_VI and AC_VO (to allow for implementation on existing h/w that can’t support extra EDCA timing parameters) Alex Ashley, NDS Ltd

Changes from r2 proposal Jan 2010 Changes from r2 proposal Reduced down to 2 options: 6 queues -> 4 EDCAF, using existing EDCA timing 6 queues -> 6 EDCAF, using existing + alternate param set dot11RobustAVStreamingAlternateEDCAFEnabled MIB variable if 6 EDCAF supported & enabled “Alternate EDCAF” extended capabilities bit for STAs to signal support Alex Ashley, NDS Ltd

Capability Signalling Jan 2010 Capability Signalling Two bits in Extended Capabilities information element to signal enhanced EDCA capabilities. Table 7-35a—Capabilities field Bit(s) Information Notes <ANA> Alternate EDCA The STA sets the Alternate EDCA field to 1 when the MIB attribute dot11RobustAVStreamingAlternateEDCAEnabled is set to true, and sets it to 0 otherwise. See 9.1.3.1 (HCF contention-based channel access) Alternate EDCAF The STA sets the Alternate EDCAF field to 1 when the MIB attribute dot11RobustAVStreamingAlternateEDCAFEnabled is set to true, and sets it to 0 otherwise. See 9.1.3.1 (HCF contention-based channel access) Alex Ashley, NDS Ltd

Alternate EDCA Parameter Set Jan 2010 Alternate EDCA Parameter Set Up to two extra EDCA parameter records AAC_VI, AAC_VO Signalled in beacon, probe response, (re)association response Similar structure to EDCA (WMM) Parameter Set Alternate Priority Info field used to indicate presence of AAC VI/VO Alex Ashley, NDS Ltd

Jan 2010 Alternate EDCA Parameter Set (dot11RobustAVStreamingAlternateEDCAFEnabled false) User Priority -> AC mapping expanded to use these extra queues, when supported Frames are still sent using existing four EDCAF Extra ACs map to existing EDCAF for transmission Uses existing EDCA Parameter Set timing Alex Ashley, NDS Ltd

Jan 2010 Alternate EDCA Parameter Set (dot11RobustAVStreamingAlternateEDCAFEnabled true) Frames are sent using six EDCAF User Priority -> AC mapping expanded to use these extra EDCA queues and EDCAF Allows use of Alternate EDCA Parameter Set timing Table 9-1aa – UP-to-AC mappings (dot11RobustAVStreamingAlternateEDCAFEnabled true)   Priority UP (Same as 802.1D user priority) 802.1D designation AC Alternate AC EDCAF Designation (informative) Lowest 1 BK AC_BK Background 2 - BE AC_BE Best Effort 3 EE AAC_VI AVI Video (alternate) 4 CL AC_VI 5 VI Video 6 VO AC_VO Voice Highest 7 NC Alex Ashley, NDS Ltd

Frames sent using existing four EDCAF Jan 2010 Frames sent using existing four EDCAF VO VI BE BK Mapping to Access Category Transmit queues for ACs EDCA functions with internal collision resolution (MSDU, UP) AC_BK AC_BE AC_VI AAC_VI AC_VO AAC_VO Scheduler gives higher priority to MSDU from the highest UP Standard EDCA timing used for transmission Figure 9-17—Reference implementation model Alex Ashley, NDS Ltd

Frames sent using six EDCAF July 2009 doc.: IEEE 802.11-10/0048r2 Jan 2010 Frames sent using six EDCAF AVO AVI BE BK Mapping to Access Category Transmit queues for ACs EDCA functions with internal collision resolution (MSDU, UP) AC_BK AC_BE AC_VI AAC_VI AC_VO AAC_VO VO VI Figure 9-17aa—Reference implementation model Alex Ashley, NDS Ltd Alex Ashley, NDS Ltd

Stream Classification Service Interaction July 2009 Month Year doc.: IEEE 802.11-yy/xxxxr0 doc.: IEEE 802.11-10/0048r2 Jan 2010 Stream Classification Service Interaction The Intra-Access Category Priority element can be used to select use of the alternate EDCA parameter set for a classified stream Removes need to always use table 9-1 mapping For an accepted SCS, the AP shall process subsequent unicast MSDUs that match the classifier specified in the SCS Descriptor. The processing of matching MSDUs depends upon the access policy assigned to the MSDU: For MSDUs that are not part of a TS, the User Priority subfield of the Intra-Access Priority element is used as the UP of these MSDUs. If dot11RobustAVStreamingAlternateEDCAFEnabled is true, matching MSDUs that are not part of a TS (as described in 11.4), or MSDUs that are part of a TS that uses EDCA or HEMM as the Access Policy, the Alternate Priority subfield of the Intra-Access Priority element is used to select whether the EDCA Parameter Set or Alternate EDCA Parameter Set is used for these MSDUs. All matching MSDUs are tagged with their drop eligibility using the value from the Drop Eligibility subfield of the Intra-Access Priority element Slide 13 Alex Ashley, NDS Ltd Page 13 Alex Ashley, NDS Ltd John Doe, Some Company

July 2009 doc.: IEEE 802.11-10/0048r2 Jan 2010 Conclusions This proposal fulfils the PAR objective of the 11aa task group: Intra-Access Category prioritization of transport streams by modifying EDCA timing and parameter selection without any requirement for deep packet inspection Creation of up to two extra EDCA parameter sets to facilitate intra-access category prioritization This proposal scales from existing h/w that just add prioritized queuing in front of existing EDCA, to implementations providing full per-AC queuing and timing Alex Ashley, NDS Ltd Alex Ashley, NDS Ltd

“The art of a good compromise is to upset everyone.” Jan 2010 Conclusions “The art of a good compromise is to upset everyone.” My work is done. Alex Ashley, NDS Ltd

July 2009 doc.: IEEE 802.11-10/0048r2 Jan 2010 Motion Move to incorporate the text changes in 11-09-0850-03-00aa-alternate-edca-parameter-set.doc into the TGaa draft Moved: Seconded: Result: Alex Ashley, NDS Ltd Alex Ashley, NDS Ltd

References 11-09-0850r3 “Alternate EDCA Parameter Set” Jan 2010 References 11-09-0850r3 “Alternate EDCA Parameter Set” 11-09-0726r0 “Stream Classification Service” 11-09/0022r0 “Implementation for Intra-AC Differentiated Services” 11-08/0764r1 “Using packet drop precedence for graceful degradation” 11-09/0264r0 “Drop Precedence in wireless, wired-wireless networks” 11-09/0371r0 “TGaa minutes for Vancouver” Alex Ashley, NDS Ltd

History Implementation for Intra-AC Differentiated Services Jan 2010 History Implementation for Intra-AC Differentiated Services IEEE 802.11-09/0022r0 Using packet drop precedence for graceful degradation IEEE 802.11-08/0764r1 Drop Precedence in wireless, wired-wireless networks IEEE 802.11-09/0264r0 Thursday March 12 TGaa + 802.1AVB meeting IEEE 802.11-09/0371r0 Stream Classification Service IEEE 802.11-09/0725r0 Alex Ashley, NDS Ltd