SR Behavior Overview CIDs 11360 Myles 27.9 289.00 802.11ax includes two spatial methods. Both methods are relatively complex and there are doubts about how well they work. It appears both are included because of these doubts.. Presumably the hope is that one mechanism does actually work. However, standards are supposed to be generally about standardising proven mechanisms (preferably one to reduce complexity and risk) or mechanims that are known to work rather than standardising experiments. The 802.11ax draft should be modified to remove at least one of the SR mechanisms. The TG should be confident that the remaiing mechanism actually works. If not then both mechanisms shoukd be removed. Reject – There is no doubt that the SRP SR mechanism is effective when an opportunity to use it is identified. The SRP mechanism relies on measured information that might be subject to some error, but engineering always must include margin for error. The OBSS PD SR mechanism has been proven, in various situations, through simulation, to be effective in producing good outcomes. The standard of quality of the evidence presented in support of the OBSS PD SR mechanism is no different than the standard that has been applied to various other features and functions which have been included in previously approved 802.11 standard amendments, and there are other features that have been included in the past that have been included with a much lower bar of quality of evidence. 11357 Alfred 27.9 289.54 It is still difficult to understand what values of the SIG-A related to which of the features. Similar for the terminologies, in certain cases they are not consistent. SRP, SR, DSRP, etc. Suggest to revew carefully so that there is no inconsistencies. Similar observation for the normative behavior. Not As in comment. Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 11357, with a note to the commenter that other changes presented in in response to other CIDs provide additional improvements in clarity and consistency beyond those marked
11556 27.9.2.1 290.40 regarding "or the received PPDU contains a CTS and a transition from BUSY to IDLE occurred within the PIFS time immediately preceding the received CTS and that transition corresponded to the end of an inter-BSS PPDU that contained an RTS that was ignored following this procedure.", this was predicated on PHY of STA issues with a value equal to BUSY. Is this trying to say that you can't ignore an RTS/CTS? as in comment See 11-17-LLLLrY 14114 Yuichi 27.9.2.1 290.40 "the received PPDU is not a non HT PPDU carrying a response frame...". The recipient only knows the content of the PPDU at the end of the PPDU, which contradicts with line 32 "a) issue a primitive before the end of the PPDU" Remove part that reads "carrying a response frame" See 11-17-LLLLrY 12188 Lv 27.9.2.1 290.51 An HE STA with should follow the OBSS_PD based on 27.9.4 Change the following condition to "(defined in 27.9.2.2 (Adjustment of OBSS_PD and transmit power) or 27.9.4 (Interaction of OBSS_PD and SRP-based spatial reuse)). See 11-17-LLLLrY 14213 Yunbo Li 27.9.2.1 290.53 HE PPDU should not be excluded in the three sub bullets. delete "non-HE" in all the sub bullets. See 11-17-LLLLrY 13152 Qi Xue 27.9.2.1 290.58 Change to "An NDP frame" As in the comment See 11-17-LLLLrY Albert 27.9.2.1 290.60 Text states "A STA that actions (a) or (b) under the conditions ...." Actions (a) or (b) not defined, need more clarity. Sentence needs to be rewritten. What are actions (a) or (b) See 11-17-LLLLrY
12019 Yee 27.9.2.l 291.30 P. 290 line 30-61 are defining spatial reuses, here the spec should also require the PPDU received is not from a SRG STA. As provided in comment. See 11-17-LLLLrY Yuichi 27.9.2.1 291.33 In order to allow efficient use of SR resource, STA should be allowed to subtract the time it took to determine that the received PPDU is an inter-BSS PPDU from its BO timer. This is especially important to effectively utilize the SR resource, because by the time the BO expires in many cases the OBSS PPDU would be already be finished. Add "If the primitive is issued before the end of the PPDU, the Backoff counter of the STA may be decremented by the time it took from the beginning of the PPDU until the primitive was issued" See 11-17-LLLLrY Yuichi 27.9.2.1 291.34 Even if the TXOP is limited to the duration of the PPDU, the STA is allowed to send an SR PPDU that extends beyond the end of the TXOP. This SR PPDU will collide with the response frame of the MU transmission. Add description as to how the SR PPDU will not collide with response to MU transmission. See 11-17-LLLLrY 14278 27.9.2.1 291.34 This rule limits the TXOP obtained by the OBSS_PD mechanism to the duration of the HE MU PPDU to prevent interfering. According to IEEE802.11 2016, start of PPDU shall be within TXOP but end of PPDU could exceed the end of TXOP so limitation of TXOP is not enough and the duration of PPDU must be limited as well. Add "and the duration of transmitting PPDU shall not exceed the end of the PPDU" after "the TXOP shall be limited to the duration of the PPDU" See 11-17-LLLLrY
14285 27.9.2.3 294.04 We should consider the case a STA whose queue is empty ignored an inter-BSS PPDU for receiving opportunity. The STA does not intend transmission which would cause interference, so the OBSS_PD SR transmit power restriction period should not be applied to the STA. Otherwise the restriction period for such a STA, e.g. a light traffic device, is going to be unreasonably long. Two suggestion. 1. OBSS_PD SR transmit power restriction period shall be applied to only a STA which starts countdown of backoff. 2. Define upper limit of OBSS_PD SR transmit power restriction period. See 11-17-LLLLrY 11942 June Wang 27.9.2.3 294.06 Should have a maximum value (such as maximum allowable TXOP duration) for OBSS_PD SR transmit power restriction period regardless when STA gains TXOP its backoff reaches zero. Since it might take a long time for backoff to reach zero in some cases. Recommend to change to --- This OBSS_PD SR transmit power restriction period shall be terminated at the end of the TXOP that the STA gains once its backoff reaches zero or TBD duration whichever is sooner". See 11-17-LLLLrY 11940 June Wang 27.9.2.3 294.07 Note 1 and Note 2 should be nomative text. Change to nomative text See 11-17-LLLLrY 11781 Smith 27.9.2.3 294.11 "TXP-Wrmax" should not have the "-" Delete "-" See 11-17-LLLLrY
As a result, the MAC may not be able to determine whether continue backoff countdown because there seems no clear indication from the PHY saying the medium is BUSY/IDLE 14119 Yuichi 27.9.2.4 295.58 There is no requirement on when the STA that issued the primitive during the PPDU re-issues the BUSY indication. If there is no such requirement, multiple SR transmissions will just collide with one another. Define requirement on how the HE STA issues the BUSY indication when a) the inter-BSS is still being sent and b)another HE STA starts an SR PPDU transmission. See 11-17-LLLLrY 12542 Liwen Chu 27.9.2.4 303.01 Add the rule that the AIFS rule still needs to be respected. As in comment See 11-17-LLLLrY SRP Behavior CIDs
11816 Li 27.9.3 296.18 According to definition of SRP PPDU, it is the PPDU that contains trigger frame, so it has to be a DL PPDU. However, in this sentence "ensuing uplink SRP_PPDU", it is referred to as uplink PPDU. This is consistent. I think this "PPDU" is meant to say the trigger-based PPDU. If so, please correct the wording. change to PPDU" Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 11816 12192 Lv 27.9.3 296.18 Only HE SU or HE EXT SU PPDU can set the SPATIAL_REUSE field in HE SIGA to SR_DELAY. Is it necessary to specify that the SR field in the Common Info field of the trigger frame shall not be set to SR_DELAY? If so, what about SR_RESTRICTED? Remove the sentence "An AP sending a trigger frame shall not set the SR field in the Common Info field of the trigger frame to SR_DELAY." Revise – TGax editor to make changes as in 11-18/0026r3 that are marked with CID 12192 13560 LEE 27.9.3 296.18 No clear description and/or defination is provided what SRP_PPDU is. Please provide the description and definition of SRP_PPDU Revise – TGax editor to make changes as in 11-18/0026r3 that are marked with CID 13560 13937 Seok 27.9.3 296.18 "...from performing SR transmission during the ensuing uplink SRP_PPDU duration." Definition of the SRP_PPDU is missed. Include the definition of the SRP_PPDU in clause 3.2. Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 13937 14291 27.9.3.0 296.24 If the STA received a Trigger frame carried in HE MU PPDU with SR_RESTRICTED indication, DSRP_PPDU-based spatial reuse can not initiate? Clarify. If so add a exception rule into the conditions below. Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 14291
Li 27.9.3.2 297.51 This paragraph specifies the value for the trigger frame SR field which is used in TB PPDU. Therefore, the values for this field should be Table 28-22 (SR setting for TB PPDU), not Table 28-21. Change "Table to "Table Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 11827 12193 Lv 27.9.3.3 298.07 Suggest to say "the max SNR margin" Please clarify it Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 12193 14120 Yuichi 27.9.3.4 298.26 Any reason why this is "PPDU" instead of "MPDU" as in line 30? change PPDU to MPDU Revise – TGax editor to make changes as in 11-18/0026r3 that are marked with CID 14120 14300 27.9.3.5 298.33 SR_PPDU reception and response transmission requirements are sufficient. If the responder no SR_PPDU in the queue, the responder will not identifies an SRP opportunity. In that case the responder will response to received SR_PPDU with no transmission power control which interferes the trigger sender. Define SR_PPDU reception and response transmission requirements to prevent the commented issue. Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 14300 12074 Jing Ma 27.9.3.5 298.34 It is not clear about what the SR_PPDU response transmission requirements exactly are by only saying " if all outstanding SRP and OBSS_PD transmit power requirements are not met by the response transmission" here. Any reference about "all outstanding SRP and OBSS_PD transmit power requirements" ? Please clarify it. as in the comment Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 12074
measured path information and the SRP parameter information together have already indicated that an SR transmission is safe. The generic PD levels no longer matter in this case. 12196 Lv 27.9.4 298.53 The OBSS_PD level should be set to positive infinity when an SRP opportunity is identified based on the reception of the PPDU. Remove "or lower". As comment Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 12196, note that a STA may choose to use a lower value if it desires. Liwen Chu 27.9.4 298.53 "positive infinity or lower" change "positive infinity or lower" to "positive or higher"??? This contradict with the further detecting DSRP frame during SRP opportunity. Fix the issue mentioned in comment. Reject – the reader has failed to notice the additional qualifier of “as it applies to this PPDU” 12198 Lv 27.9.4 298.65 SR_DELAY is not a value in the Common Info field SPATIAL_REUSE of a Trigger frame Remove "or SR_DELAY" Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 12198 12200 Lv 27.9.4 299.02 Remove "or As comment Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 12200, which modify the applicability of the OBSS_PD level in question, but do not acquiesce to the commenter’s request for removal of “lower” 12202 Lv 27.9.4 299.03 Add the following sentence at the end of the paragraph "and may use a value equal to the receive power of the HE TB PPDU plus 1 dB for the level for the duration of this HE TB PPDU" As comment Revise – TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 12202 12543 Liwen Chu 27.9.4 299.08 a value of negative infinity for the OBSS_Pdlevel contradicts with As in comment Reject – the reader has failed to notice the additional qualifier of “as it applies to this PPDU”
12204 Lv 27.9.4 299.09 Remove "and shall use a value equal to the receive power of this PPDU minus 1 dB for the ED level for the duration of this PPDU" As comment Accept SPATIAL_REUSE parameter of the TXVECTOR CIDs 12545 Chu 27.11.6 307.36 why OBSS PD is excluded? Fix the issue mentioned in comment. Reject – the condition is HESRP implemented, so this only relates to the SRP case. Liwen Chu 27.11.6 307.39 HE MU, HE SU have no array of four values? Clarify it Reject – see the definition of the for each of the HE PPDU types. 11932 June Wang 27.11.6 307.58 "when permitted by other conditions," is vague provide references such as "as permitted by other conditions in ... subclauses." Revise - TGax editor to make changes as in 11-18/0026r3 that are marked with CID 11932 12269 Lv 27.11.6 307.58 The subfield in the SR Control indicates whether non-AP STAs that are associated with the AP that transmitted this element may set the TXVECTOR parameter SPATIAL_ REUSE to SR transmissions.So here should be "may" not "shall". as comment Revise - TGax editor to make changes as in 11-18/0026r3 that are marked with CID 12269 Li 27.11.6 307.59 There should be a reference section for the "other conditions". Either add a section number as a reference for the "other conditions", or list the conditions when this field is set to and when it is se to SRP_DISALLOWE Revise - TGax editor to make changes as shown in 11-18/0026r3 that are marked with CID 11868
12291 Ryu 27.11.6 308.50 One more condition to set the TXVECTOR parameter SPATIAL_REUSE to should be added. Modify the text as: A STA set the TXVECTOR parameter SPATIAL_REUSE of an HE PPDU to SRP_DISALLOW or, if permitted, to if the STA is an HE STA and the SR Disallowed subfield of the SR Control field of the most recently received Spatial Reuse Parameter Set element from its associated AP is equal to 1 or if the STA has not received a Spatial Reuse Parameter Set element from its associated AP. Reject – the default condition is that the STA has a choice on the setting, and is only restricted in its choice if the AP makes this restriction by sending the element. In the absence of the AP sending the element, the AP is allowing the STA to have the choice, rather than directing the choice of the STA. 14310 27.11.6 308.50 This paragraph defines rules for only non-AP STA, but rules for AP should be defined. Add the following condition at the end. "if the STA is an HE AP and the SR Disallowed subfield of the SR Control of the most recently transmitted Spatial Reuse Parameter Set element is equal to 1" Reject – the sixth paragraph of the subclause already gives the AP permission to make this setting. There is not and does not need to be a correspondence or dependenct with regard to the setting that the AP imposes upon its member STAs through the SRP Disallowed field value. 14311 27.11.6 308.50 If non-AP STA has not received a Spatial Parameter Set element from its associated AP, the non-AP STA shall set the TXVECTOR parameter SPATIAL_REUSE to SRP_DISALLOW. As commented. Reject – the default condition is that the STA has a choice on the setting, and is only restricted in its choice if the AP makes this restriction by sending the element. In the absence of the AP sending the element, the AP is allowing the STA to have the choice, rather than directing the choice of the STA.