Resolution for CID 118 and 664 Date: 2011-05-11 Authors: Month Year doc.: IEEE 802.11-yy/xxxxr0 doc.: IEEE 802.11-yy/xxxxr0 Resolution for CID 118 and 664 Date: 2011-05-11 Authors: Slide 1 Page 1 John Doe, Some Company John Doe, Some Company

Comment 118 and 664 related to TXOP PS Month Year doc.: IEEE 802.11-yy/xxxxr0 Comment 118 and 664 related to TXOP PS CID Subclause Page Line Comment Type Comment SuggestedRemedy Response 118 11.2.1.4a 61 16-20 TR The TXOP Power Save scheme allows any STA that is not addressed to by the SU/MU packet goes into the Doze state during the TXOP. However, within a TXOP, the AP may transmit to multiple STAs or groups, say first group A then group B. If a STA belongs to group B, it will go to to DOZE state after receiving the packet the AP transmits to group A. The STAs in group B will fail to receive any packet for the remainder of TXOP. Change lines 18-20 of sub-clause 11.2.1.4a as follows: 1) A VHT AP that obtains a TXOP for VHT transmissions shall indicate non-AP VHT STAs using TXOP_PS_NOT_ALLOWED in TXVECTOR whether or not they are allowed to enter Doze state if within the obtained TXOP or the remaining TXOP, it only transmits to one STA or STAs in the same Group. Otherwise, TXOP_PS_NOT_ALLOWED shall be set to 1 and non-AP VHT STAs shall not enter Doze state. Agree in principle. 664 22.3.9.2.3 101 53 How often the value of the "No TXOP PS" field may be changed? Once every PPDU transmission, once every TXOP or once every beacon interval? Please add the details how often the value of NO TXOP PS field may be changed. Agree. John Doe, Some Company

Proposed Text change from 593 r5 11.2.1.4a Power management during VHT transmissions The power management scheme described in this section is applicable only when the dot11VHTTXOPPowerSave is true at VHT AP. The non-AP VHT STAs that are in Active mode (see Table 11-1—Power Management modes) and have dot11TXOPPowerSave set to true operate in TXOP power save mode. A VHT AP may or may not allow non-AP VHT STAs in TXOP power save mode to enter the Doze state during a TXOP. A VHT AP shall indicate this using TXOP_PS_NOT_ALLOWED parameter in TXVECTOR of a frame with FORMAT VHT..The value of this parameter in the TXVECTOR of all VHT PPDUs transmitted by VHT AP shall remain same for the duration of TXOP. The value of this parameter in the TXVECTOR of all VHT PPDUs transmitted by VHT AP may be changed from 1 to 0 during the TXOP to enable TXOP PS for the remainder of the TXOP. The value of this parameter in the TXVECTOR of all VHT PPDUs transmitted by VHT AP shall not be changed from 0 to 1 during the TXOP.

Discussions For CID 118: If during one TXOP, AP has packets to transmit to multiple STAs or multiple groups of STAs that operate in TXOP power save mode, TXOP PS can not be applied to the whole TXOP. For example, if STA1, STA2 both operates in TXOP power save mode and TXOP PS is allowed then STA2 will go to DOZE state till the end of TXOP when it receives the first packet the AP transmits to STA1. The solution is to allow the AP to change the TXOP_PS_NOT_ALLOWED bit to 0 as illustrated in the following figure: For CID 664: The text change states that the TXOP_PS_NOT_ALLOWED bit can only change one time from 1 to 0 during a TXOP but can not change from 0 to 1. This is the clarification on how often this field can be changed. STA1 or STA Group1 STA2 or STA Group 2 TXOP Start TXOP End Set TXOP_PS_NOT_ALLOWED = 0 here Set TXOP_PS_NOT_ALLOWED = 1 at the beginning of a TXOP No STA goes to DOZE state All other STAs operating in TXOP PS mode goes to DOZE state