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I read with interest your 20/0408 and 20/1045 presentations. Forgive me for coming in late and for not hearing the original presentations and maybe I have not understood the proposal well. I spent a lot of time in the past on QoS, EDCA, HCCA, Video and Voice. I will start by stating that EDCA has served for over 15 years – its problem has always been that it is self- policing. I spent some time proving that too many devices simply cheat. Used correctly it might do better. I also spent much time working with HCCA, which is uses an HC, and it was proved that it worked very well and increased the efficiency and throughput of networks. The requirement for a TSPEC is often seen as a ‘problem’, but the TSPEC is a way to clearly define the QoS requirement. So , splitting the time into allocated and free is not new. I want to make sure I understand your proposal. The AP advertises the Slot Duration and number of slots, plus the EDCA parameters that can be used in the “priority slots”. Then STAs request assignments of slots. The AP then advertises the allocations and timing. Contrast this with HCCA. STAs request allocations based upon a set of parameters that describe their QoS requirements (TSPECs). The AP/HC grants the allocations and advertises the schedule. At allocated time, AP/HC starts the HCCA TXOP, if no traffic, or ends early, AP/HC releases the medium. AP/HCs can negotiate with overlapping AP/HCs so as not to allocate over each other. On the face of it, your slotted scheme is very similar to HCCA where the AP/HC grants the allocations and advertises the schedule. I can’t see in your presentation how the STAs request their slots or the negotiation, but I would assume it is, or could be, very similar to the ADDTS scheme. A major problem for Wi-Fi and QoS is OBSS and I would draw your attention to the work carried out in 11aa. 11ax should have sorted out Spatial Reuse better but in 11aa overlapping APs can exchange their allocations and negotiate if they have to share. This is important in my view. So for some specific basic questions: · What are the procedures for STAs to be allocated slots, how many and how often? I suggest that the TSPEC should be used as a template for the parameters required. · Do you intend for overlapping APs to negotiate and share in a controlled manner? · Can you show that this slotted scheme is better than HCCA? · In HCCA if no traffic in the allocated TXOP, the HC releases the medium immediately. In your slotted scheme I assume that STAs note that traffic has ceased and contend again. Is the concept of a TXOP still maintained, i.e. the AP starts the TXOP in the slot or the STA simply takes it? · How reliant is this on the STAs accurately using the random back off? STAs are still policing themselves. One advantage of HCCA is that the AP starts the TXOP every time and hence controls the medium. Does the slotted scheme have this same advantage or is it still at the mercy of STAs using advantageous settings? I am not a regular 11be attendant so I would be grateful if you could let me know when this will be next discussed. Thanks Graham From: Chunyu Hu [mailto:chunyuhu07@xxxxxxxxx] Hi, all: Starting a thread for Q/A for the doc 11-20/1045r3 to cover remaining Q/As. I captured Jay, Mohamed, Liangxiao, and Sharan. Other please also feel free to ask questions here or send me separate emails. Thanks. Chunyu To unsubscribe from the STDS-802-11-TGBE list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-11-TGBE&A=1 To unsubscribe from the STDS-802-11-TGBE list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=STDS-802-11-TGBE&A=1 |