37 Ahmadreza Hedayat 25.5.2 When multiple Trigger frames and/or HEC feilds with UL MU response scheduling (Trigger Info) in the MAC header of MPDU(s) are carried within the same PPDU, some of the fields of the Common Info of the Trigger frame(s) and the HEC field should be the same. For instance, the duration of the upcoming trigger-based UL MU should be the same across all Trigger frame(s) and HEC fields with UL MU response scheduling (Trigger Info) in the MAC header of MPDU(s). Similarly, the LTF-type and number and GI duration should be the same across all the control fields that carry Trigger info. Add the described behavior of the STA that aggregates multiple Trigger frames and/or HEC fields with UL MU response scheduling (Trigger Info) in MAC header of MPDU(s) within the same PPDU. Revised. Some limitations are included which are needed for interoperation. It is not necessary to instruct the AP on how to all possible erroneous settings of the trigger infromation across STAs, such as different duration. Given the PHY limitations, any AP should know what to do. See resolution in doc 16/929r1 38 Ahmadreza Hedayat 25.5.2 Other behaviors of a STA that schedules UL MU transmission via HEC field with UL MU response scheduling should be included, such as: (a) in a unicast frame the content of HEC field with UL MU response scheduling across an AMPDU should be the same, (b) within a multicast frame there should not be any HEC field with UL MU response scheduling (since it'd not be clear which of the recepinets of the multicast frame should respond), etc As in the comment. Revised. Some limitations are included which are needed for interoperation. It is not necessary to instruct the AP on how to avoid all possible erroneous settings of the trigger infromation across STAs, such as different duration. Given the PHY limitations, any AP should know what to do. See resolution in doc
39 Ahmadreza Hedayat 25.5.2 Regarding "An UL MPDU/A-MPDU is the acknowledgement of the Trigger frame. When the AP receives MPDU correctly from at least one STA indicated by trigger frame, the frame exchange initiated by the trigger frame is successful.", it seems this rule does not consider the case where an AP schedules an UL MU transmission for multiple STAs, but the STA(s) that have assignmnets on the Primary 20MHz do not respond, in which case the primary channel could be idle for the duration of the PPDU in which case the medium could be grabbed by otehr OBSS STAs ... Suggest to consider the case mentioned in this comment, and change this rule so that when at least one STA with RU assignment on the Primary 20MHz channel responds then the UL MU transmission is considered successful. Reject. In case any of the STAs replies, the exchange is happening and AP should keep receiving the frame. Declaring it a failed exchange has consequences on the definition of other related behavior (e.g. backoff) 40 Ahmadreza Hedayat 25.5.2 "The inter frame space between a PPDU that contains a Trigger frame and the triggered HE trigger-based PPDU is SIFS." "The frame space between a PPDU that contains a Trigger frame or contains an HEC field with UL MU Scheduling and the triggered HE trigger-based PPDU is SIFS." Revised
44 Ahmadreza Hedayat 25.5.2 It seems with the same logic CTS should be included in this list: "All HE trigger-based PPDU(s) solicited by the Trigger frame containing ACK/BA and the length of the HE trigger-based PPDU is below a TBD threshold.". This is useful when an AP sends data frame to a set of STAs and solicits ACK/BA in response, and sends or MU-RTS to another set of STAs and solicits CTS in one or more 20MHz sub-channels. Revise; "All HE PPDU(s) solicited by the Trigger frame containing ACK/BA or CTS and the length of the HE trigger-based PPDU is below a TBD threshold." Reject. Allowing a mix of legacy CTS response and UL Mu PPDU reponse woud be yeat another new PHY mode. 170 Alfred Asterjadhi 25.5.2.2.1 Some clarifications are needed in this itemized list: Clear indication when Trigger frame(s) or UL MU Response Scheduling in the HE variant HT Control fields are present in the DL PPDU that solicits a Trigger-based PPDU. For recipient STAs that are not associated with the AP a random access RU can be allocated, as such the AID value in this particular case should be 0. Also if the Trigger frame is the first frame in the then we need to clarify that BA/Ack frames are the second ones (baseline dictates them to be the first ones), and last but not least, the information contained in Trigger frames or UL MU Response Scheduling (which is the correct terminology to use rather than "Trigger Information field in MAC Header TBD") do not conflict with eath other (or with same signaling in different RUs of the same DL PPDU). Perform the same changes to the 3rd paragraph of 25.5.2.3 as well (those that apply of course). As in comment. Revised. Used AID=0 for random access. Clarified the order of the trigger and BA. It is not necessary to instruct the AP on how to avoid all possible erroneous settings of the trigger infromation across STAs, such as different duration. Given the PHY limitations, any AP should know what to do. See resolution in doc 16/929r1 based
175 Alfred Asterjadhi 25.5.2.3 There are many missing items in the setting of the TXVECTOR parameters for the HE trigger-based PPDU. Ensure that the list is complete for the Trigger frame (according to the fields specified by the trigger frame) and for the UL MU Response Scheduling (according to the fields specified in the HE variant HT Control field, and default (from DL MU PPDU?) values for those not specified in the field). As in comment. Revised. Agree. See changes in this document for the Ttrigger frame response and in document 16-776 fro the UL MU reponse Scheduling HE control field 176 Alfred Asterjadhi 25.5.2.3 When the Trigger Type is not equal to 0 (means MU RTS, MU BAR, MU BRP variants) we need to specify that the STA shall not solicit an immediate response from the AP to the trigger-based PPDU (e.g., the QoS Null frame if added shall have the Ack Policy to No Ack). As in comment. Revised See resolution in doc 432 Hart 25.5.2.2.1 "AP AP shall not send ... unles the STA is UL MU Capable" For 11ax to be relevant, all non-APs need to be UL MU Capable (e.g. UL OFDMA) Revised. Removed reference to capability See resolution in doc 16/929r1 436 Hart 25.5.2.2.3 Definition of successful is unclear Insert xref Revised Definition of successful is linked to the 460 Daewon Lee 25.5.2.1 How the AP obtains the medium access for DL MU and UL MU operation is not defined. It is not whether DL MU EDCA operation is same as 11ac DL MU EDCA operation or not. Given that trigger frame is control frame, it is not clear what the AC of the trigger frame should be, and how it would content for medium (e.g. using which backoff window size, etc) Add a new section under MU operation regarding EDCA for DL MU and EDCA for UL MU either in chaper 10.22.2 HCF contention based channel access (EDCA) or chapter 25.5 MU operation. Define the details of medium access operation for MU. Reject. the AP may use any AC to send the trigger frame
1531 Mark RISON 25.5.2.2.3 "When the AP receives MPDU correctly from at one STA indicated by trigger frame, the frame exchange initiated by the trigger frame is successful." -- hm, but a frame exchange includes stuff following after SIFS, so it's not really that the frame exchange is successful, it's that the transmission of the Trigger frame is successful Reword in of success of the TF transmission Revised the clause related to TXOP continuation and recovery are referred. See resolution in doc 16/929r1 1534 Mark RISON 25.5.2.3 "The CP_LTF_TYPE parameter shall be set to the value indicated by the CP-LTF subfield of the Common Info field of the eliciting Trigger frame" -- and what if there wasn't a TF but just a trigger MAC header? Ditto for the subsequent parameters Explain how the parameters is set in that case Revised TXVECTOR paramters are defined See resolution in doc 1538 Mark RISON 25.5.2.3 "The content of each individual A-MPDU in an HE MU PPDU is based on the rules specified in 10.13.1 (A-MPDU contents) and the additional rules described in this clause." -- does "this clause" mean "this subclause"? If it does, then just simplify and say "with the following additional rule:". If it does not, it's too general, and specific rules need to be pointed to Revised Remove the sentence since it is obvious that any follows the A-MPDU context rules See resolution in doc 1540 Mark RISON 25.5.2.3 "one MPDU of the required type" -- where are the required types specified? Table 9-ax2 just says what the trigger type is, not what MPDUs are required in response Add something to giving the required response type Rvised 1541 Mark 25.5.2.3 "If the STA does not have a frame of the required type, the STA should transmit QoS Null frame." -- but it could also transmit a Beacon frame? Or nothing? Also missing article before "QoS" Clarify what the STA may alternatively do if it does not do what is recommended Revised the STA shall either not transmit the response or transmit QoS Null frame
2271 Woojin Ahn 25.5.2.2.3 When AP accesses the medium for triggering HE TRIG PPDU, AP can be aware of the ACs of the triggering UL traffic by buffer status reports. For fair medium contention, AP must consider the ACs of allocable UL traffics reported from the buffer status reports. Insert the following at 25.5.2.2.3 line 57 "UL MU medium access rule shall consider the ACs of allocable UL traffics reported from the buffer status reports." Reject. The proposed resolution is incomplete. Also, STAs are allowed to send any TID, hence AP would not know how the allocated UL Mu PPDu would be used by the STA. 2321 Yasuhiko Inoue 25.5.2.1 Following expressions are not to me. "Trigger Information TBD contained in the MAC Header" in line 19, and "Trigger Information Field info in MAC header TBD" in line 25. Clarify, please. Revised Al occurrences are now referred to as “UL MU Response Scheduling subfield” See resolution in doc 2381 Yonggang Fang 25.5.2.2.1 change a "PPDU" to a "Trigger frame" for easy understanding as the "HE trigger-based PPDU shall be elicited by the trigger frame. Revised See resolution in doc 16/929r1 2382 Yonggang Fang 25.5.2.2.1 What is the definition of trigger frame and trigger information? Revised Trigger is a welld efiend frame in clause 8
2645 Young Hoon Kwon 25.5.2.3 In current spec. (REVmc_D5.2), after transmitting a frame that requires an immediate acknowledgement, the STA shall perform ack procedure, and the retry counter value shall be incremented every time transmission of a frame fails (see 10.22.2.11.1). However in case of UL MU transmission, as a transmission is made as an immediate response to a Trigger frame, it is not clear how to handle the retry count. As mentioned in the comment, clarify how to set retry count value in case a transmissio that requires immediate response is made as a immediate response to a Trigger frame, and modify subclause 10.22.2.11.1 of REVmc_D5.2 accordingly. [Text?] Revised See presentation 16/880 2646 Hoon Kwon 25.5.2.3 With this condition, random access is not allowed. Add a case that enables random access in the conditions list. Revised Added See resolution in doc 16/929r1 2682 Yuhei Nagao 25.5.2.2.1 In the UL MU operation, the of the User Identifier subfield of the Per-User Info field is undefined for TF recipient STAs that are not associated with the AP. We need to be clear what purpose of the User Identifier subfield for unassociated STAs with the AP. Clarify Revised Clarified See resolution in doc 16/929r1 2706 Yuichi Morioka 25.5.2.2.1 Is this restriction necessary? If single MPDU Trigger can be responded in SIFS, there should be no problem even if the Trigger frame is the last frame in an A-MPDU. Remove sentence starting "If a Trigger is..." Revised Control frames are placd at the beginning of the PPDU. 2707 Yuichi Morioka 25.5.2.2.3 What happens if the frame exchange initiated by the trigger frame is "successful"? Define what the AP should do if the exchange is successful. Revised Please modify section 25.5.2 as follows