Yuichi Morioka 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 PHYCCARESET.request 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 the PHYCCARESET.request primitive was issued" Rejected – the concept is interesting, but the proposed resolution is incomplete because it creates a new problem – i.e. the simple subtraction proposed will cause all STAs with a backoff count less than the the determination time to hit zero at the same time causing a collision – a complete proposal needs to deal with this problem. Yuichi Morioka 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 of the MU transmission. Add description as to how the SR PPDU will not collide with response to MU transmission. Revise – see resolution for CID 14278 which adds further restriction. Yusuke Tanaka 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 not exceed the end of the PPDU" after "the TXOP shall be limited to the duration of the PPDU" Revised – agree with the commenter. Apply the changes as proposed in doc . Albert Petrick Missing periods add missing periods the end of all subbullet text in this clause Revised – with the comment. Apply the changes as in doc .
Geonjung Ko According to the subclass 27.11.6 (SPATIAL_REUSE), when a STA transmits a Trigger frame, it is recommended to set the TXVECTOR parameter SPATIAL_REUSE to SR_DELAY or SR_RESTRICTED. Since a Trigger frame is allowed to be sent in a HT or VHT PPDU, there may be other frames aggregated to the Trigger frame in the same PPDU. If an inter-BSS STA transmits a frame on the OBSS_PD-based SR on the PPDU, STAs solicited by the Trigger frame may not be able to respond to the Trigger frame after the CCA. Therefore, we can define the operation for a STA which received a Trigger frame, for example, the similar operation when the Spatial Reuse field is set to SR_DELAY or SR_RESTRICTED. Add "If the PHY-CCARESET.request primitive is issued before the end of the PPDU, and a TXOP is initiated within the duration of the PPDU, then the TXOP should be limited to the duration of the PPDU if a Trigger is in the PPDU." Revised - Protection with SR restricted is mostly for the cascaded case (as in the non-cascaded case, the trigger will mostly be for Acks and will set CS required to 0). Cascaded only applies to HE MU PPDUs. Now there could be a single trigger frame carried in VHT of HT format that triggers a long PPDU and we want to make sure that the TB PPDu is protected. For HE, we set it to SR_DELAY. For HT format, the classification as inter-BSS PPDU can only be done at the end of the PPDU when decoding the MAC header, so the SR will effectively be delayed at the end of the PPDU, which will then naturally protect the TB PPDUs. For a trigger carried in VHT, it is true that a STA can classify it as PPDU based on the VHT-SIG field, so we could have an issue here. But there does not seem to be any reason why we would use VHT PPDU to send a trigger frame. The proposed resolution is therefore to include a note to recommend the AP not to transmit trigger frames in VHT PPDU format. BSS
the changes as proposed in doc . James Yee In Equation (27-3), replace "OBSSPDmin" with "OBSS_PDmin" and "OBSSPDmax" with "OBSS_PDmax" since these are the right terms used in other parts of the spec(e.g. figure 27-9). As provided in comment. Revised – agree with the comment. Make the changes as proposed in doc . Aboulmagd This clause provides the rules for adjusting OBSS_PD value. However it doesn't state when this change is requested, i.e. what event does trigger this adjustment? as in comment Rejected – a STA is allowed to apply OBSS_PD SR under specific conditions. If it meets these conditions it can apply this mechanism. In such case, it needs to select OBSS_PD and TxPower values. The selection process is implementation dependent but must adhere to the rules defined in this subclause. Yusuke Tanaka "OBSSPD" and "OBSS PD" should be unified to "OBSS_PD" As commented. Revised – agree with the comment. Make the changes as proposed in doc . Graham Smith "...and shall respect the condition defined in Equation". I can't find any other use of this expression in 11md or this document. Replace Replace cited text with "in accordance with Equation" Revised – with the comment. Make the changes as proposed in doc . Graham Equation 27-3 indicates that the TX power may be less than the simple rule and could, in fact, be set to zero. Seems pretty dumb to me to have the < sign there as it is bad enough already and can one really see devices using less than the permitted power if they were dumb enough to do this anyway? Replace Γëñ with = Rejected – one must ask and answer the following question: what are the consequences of a STA using a TXP value less than what is permitted? Is it a net positive or negative for the individual STA, and is it a net positive or negative for the system? Unless
based Guoqing Li In Table 27-7, the use of 0 and 1 is understood, but this is not setting a value for a particular field. Change 0 and 1 to "yes" or "no". Change 0 and 1 to "yes" or "no". Revised – with the comment. Clarify by modifying the title of the column. Apply the changes proposed in doc . Yusuke Tanaka This sentence should be in 27.9.3 SRP-based spatial reuse operation As commented. Revised – agree with the comment. Apply the changes proposed in doc . Dorothy Stanley regarding "shall not perform SR transmissions", why is this in the OBSS_PD-based section? as in comment Revised – agree with the comment. Apply the changes proposed in doc . Dorothy Stanley the grammar in the paragraph is undecipherable as in comment Revised – with the comment. Apply the changes proposed in doc . Yuichi Morioka What happens to the case where the HE STA ignores an inter-BSS PPDU but does not initiate countdown because it has nothing to send? The power restriction period should not start in this case. Add description that the power restriction period only starts when the STA starts countdown. Rejected – the power restriction is needed even if the count is already zero with an empty queue because the STA might be triggered during this time and needs to to follow the power restrictions because it declared the medium to be IDLE based on SR. In the non-zero count case with an empty queue, the countdown begins anyway, because if you have a count and you have what is indicated to be an idle medium, you count down, regardless of your TX queue condition. Graham Smith "If a STA ignores an inter-BSS PPDU following the procedure in 27.9.2.1 (General), using a chosen SRG OBSS_PD level, or a chosen OBSS_PD level shall start an OBSS_PD SR transmit power restriction period." Does not read right. . Replace text with "If a STA ignores an inter-BSS PPDU following the procedure in 27.9.2.1 (General), using a chosen SRG OBSS_PD level, or a chosen non-SRG OBSS_PD level, then the STA shall start an OBSS_PD SR transmit power restriction period. " Revised – agree with the comment. Apply the changes proposed in doc .
James June Wang In Figure 27-10 "S2 max TXPWR is equal to max (..." should be change to "min (... " as indicated Revised – agree with the comment. Apply the changes proposed in doc . Sigurd Schelstraete In Figure 27-10, SR S2 detects all inter-BSS packets and resumes its AIFS/BO processing once it has established that SR can be applied. However, in the figure inter-BSS transmission OBSS PPDU D1'-S1' is ignored by SR S2, even though the AIFS/BO counter has not yet reached zero. Why is this? Clarify Revised – add some text to clarify that S2 does not receive OBSS PPDU from D1’ and therefore continues decrementing backoff. Apply the changes as proposed in . Guoqing Li In this figure It is more reasonable that the S2 max is equal to min (...), not max (...). The STA should honor the power contraint calculated over all the previous ignored OBSS PPDU. change max (...) to min (...) Revised – agree with the comment. Apply the changes proposed in doc . kaiying Lv Change the " max (NON SRG TXPWRmax1, NON SRG TXPWRmax 2, SRG TXPWRmax 3)" in the figure to "min (NON SRG TXPWRmax1, NON SRG TXPWRmax 2, SRG TXPWRmax 3)" as comment Revised – agree with the comment. Apply the changes proposed in doc . Yusuke Tanaka In Figure 27-10, S2 max TXPWR should be equal or lower than the minimum TXPWERmax among all TXPWRmax from ongoing OBSS_PD SR transmit power restriction periods. Change "S2 max is equal to max" to "S2 max TXPWR is equal to min" in Figure 27-10 Revised – agree with the comment. Apply the changes proposed in doc .
Yusuke Tanaka sentence describes advantages of adjusting the OBSS_PD level and transmit power from the view of system level. However a STA itself can't be aware of system level improvement but can be aware of only the STA's performance by itself. Advantages from the view of the STA should be added, otherwise there is no incentive or motivation for the STA to take adjusting the OBSS_PD level and transmit power. Add description about advantage form the view of the STA like follows; The STA which adjusts the OBSS_PD level and transmit power can ignore transmitted signals received from outside the range which it intends to execute communication and gain opportunity to comunicate with intended partner. Revised – This sentence is removed as part of resolution of comment 11774. CIDs for clause 9.4.2.243 Comment Proposed Change Resolution Albert Petrick In Figure 9-589dd-(SR Control field format) the Reserved field shows bits (B5-57) as Reserved. Text is missing of logical default setting. In the text define the default value of the "Reserved. Set to 1." Rejected – In section 9.2.2, it is written that “reserved bits and fields are set to 0” Carol Ansley missing word missing "during" before "SRP-based SR transmissions." Revised – agree with the comment. Apply the changes as proposed in doc . Regarding, "The Spatial Parameter Set element provides information needed by STAs when performing OBSS_PD-based spatial reuse", what about SRP Disallowed in the SR Control Field? I do not believe it applies to OBSS_PD-based SR. as in comment Revised – agree with the comment. Apply the changes as proposed in doc what is "Non-OBSS_PD SR Disallowed"? as in comment Revised – agree with the comment. Apply the changes as proposed in doc what are the values of as in comment Revised – Reference normative text for clarification. Apply the changes as proposed in doc 25
NOTE 2—The STA’s power is always equal or lower than the minimum TXPWRmax among all TXPWRmax from ongoing OBSS_PD SR transmit power restriction periods. (#5207, #5496, #9315, #9946)NOTE —Equation (27-4) is equivalent to the condition defined in Equation (27-3). NOTE —Anytime, even if TXPWRmax is unconstrained, the STA has to respect the transmit power restrictions defined by 11.8.6 Transmit power selection. An example of OBSS_PD SR operation is shown in Figure 27-10 (Example of OBSS_PD SR operation).