From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-x433.google.com (mail-wr1-x433.google.com [IPv6:2a00:1450:4864:20::433]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.bufferbloat.net (Postfix) with ESMTPS id 89A3B3B29D for ; Thu, 30 Jan 2020 20:20:22 -0500 (EST) Received: by mail-wr1-x433.google.com with SMTP id a6so6519284wrx.12 for ; Thu, 30 Jan 2020 17:20:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=broadcom.com; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=g/9XimgbcZPppkAH4tntXmP5p+/0R4paEtbQnxl0YgQ=; b=EKdohARNxFpW8oeXxMibfPMsuEZLJjUAU71qTFixJEg8BZo1h9FbG5CJeK4VstX/PC 9m2aak/APJM3pW7aQYygdbgg/Ci88sS5lAtxk/wP5VgYeSHguLygtlkstvhxvSFcVFWm KNSPbJXzhAR+kUWTMFtCuptz+qXqnBI5Mda3w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=g/9XimgbcZPppkAH4tntXmP5p+/0R4paEtbQnxl0YgQ=; b=pejRNQJ4Jf6I8lXky4yX4wApCCBDV57zygwkRXlyQZq8nfC4P1uNfbRj1ALvoT5rvg eExY1byKGI8PfwbpW5KbxVwY/uw2iHDXMuNUjoPo0MLK6i5jm+N/irEfxSlIFp1O7y9K 4AgCrxr6F3ZoU4Da+SSkY4aVu/qj7CoM0SKJTmrlQpfWqdlZzJu3VNiKvM8Ys99sI0VY zUwX9ukUMNbG/ftyIjlJCO+UCpwjGZOrqF9VI6pn01zk1fKJYUHVXx8R9ZMmKTck/9sw zHM+3LfBsrPhbB8HEMrE4q4c/mCxYcfJrMy2jN5uqBW+f0/yiKcIgWO8tqVPk6axR/o6 awrg== X-Gm-Message-State: APjAAAXmTUEP58X36Xm8iB7MIKHTVpBnthnmN5ZQjT6UbIPmIwikldpq cTLb4zHlbfSQDeiQfjvzYMhoLaexi7HZKe+ZX17QzFb3 X-Google-Smtp-Source: APXvYqy9tr6OCeDs89FEJvpWiBpnvRsrvr8Re930yDyIg+kY+4LnOUNxOHRlrk6VtuZwWq5xVo2G6dpd2pYWI8Vi7m4= X-Received: by 2002:a5d:6ca1:: with SMTP id a1mr8354778wra.36.1580433621584; Thu, 30 Jan 2020 17:20:21 -0800 (PST) MIME-Version: 1.0 References: <69103D46-8F04-4468-802B-142CC2DABF0F@gmail.com> <0928D44A-4F3A-462D-854E-91B653E40B1C@gmail.com> <87a764ziiy.fsf@taht.net> In-Reply-To: <87a764ziiy.fsf@taht.net> From: Bob McMahon Date: Thu, 30 Jan 2020 17:20:09 -0800 Message-ID: Subject: Re: [Make-wifi-fast] Wi-Fi 6 - how many of our assumptions does it violate? To: Dave Taht Cc: Rich Brown , Make-Wifi-fast Content-Type: multipart/alternative; boundary="0000000000009b616f059d6560cf" X-List-Received-Date: Fri, 31 Jan 2020 01:20:22 -0000 --0000000000009b616f059d6560cf Content-Type: text/plain; charset="UTF-8" It's part of the reasons iperf 2.0.14 has so many new latency, trip-time, start-time, connect, etc related features. Peak avg throughput is no longer a valid proxy for "performance." >From a testing view, attenuation or range is no longer sufficient either. Phase shifters are needed per things like VR/AR as truly optimizing the number of spatial streams is needed too. The loss function(s) to be optimized (minimized) is far from trivial in both the definition and in [re]-computing in "real-time" WiFi engineers have more work to do. Bob On Thu, Jan 30, 2020 at 2:28 PM Dave Taht wrote: > Rich Brown writes: > > >> On Jan 24, 2020, at 9:06 AM, Rich Brown > wrote: > >> > >> I saw this overview of the now-in-testing Wi-Fi 6 at > >> > https://www.howtogeek.com/368332/wi-fi-6-what%E2%80%99s-different-and-why-it-matters/ > >> > >> Its multiple MIMO streams and maybe talking to multiple devices at a > >> time seem as if they might be outside the assumptions we use. > > > > It's worse than I thought. I just watched this explainer video from > > ExtremeNetworks: https://www.youtube.com/watch?v=owBrkFk9afM > > > > If I understand correctly, they want the AP to solve a hard > > (bin-packing) problem, in real-time, with unclear rules for maximizing > > client goals (should the VoIP packet go first?). And no mention of > > airtime fairness or latency... > > > > Or am I missing something? Thanks. > > No, they punted on these things in the design. > > > > > Rich > > _______________________________________________ > > Make-wifi-fast mailing list > > Make-wifi-fast@lists.bufferbloat.net > > https://lists.bufferbloat.net/listinfo/make-wifi-fast > _______________________________________________ > Make-wifi-fast mailing list > Make-wifi-fast@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/make-wifi-fast --0000000000009b616f059d6560cf Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
It's part of the reasons iperf 2.0.14 has so many new = latency, trip-time, start-time, connect, etc related features. Peak avg thr= oughput is no longer a valid proxy for "performance."

From= a testing view, attenuation or range is no longer sufficient either.=C2=A0= Phase shifters are needed per things like VR/AR as truly optimizing the nu= mber of spatial streams is needed too.

The loss function(s) to be op= timized (minimized) is far from trivial in both the definition and in [re]-= computing in "real-time"

WiFi engineers have=C2=A0more wor= k to do.

Bob

On Thu, Jan 30, 2020 at 2:28 PM Dave Taht <dave@taht.net> wrote:
Rich Brown <richb.hanover@gmail.com> writes= :

>> On Jan 24, 2020, at 9:06 AM, Rich Brown <richb.hanover@gmail.com> wrot= e:
>>
>> I saw this overview of the now-in-testing Wi-Fi 6 at
>> https:= //www.howtogeek.com/368332/wi-fi-6-what%E2%80%99s-different-and-why-it-matt= ers/
>>
>> Its multiple MIMO streams and maybe talking to multiple devices at= a
>> time seem as if they might be outside the assumptions we use.
>
> It's worse than I thought. I just watched this explainer video fro= m
> ExtremeNetworks: https://www.youtube.com/watch?v= =3DowBrkFk9afM
>
> If I understand correctly, they want the AP to solve a hard
> (bin-packing) problem, in real-time, with unclear rules for maximizing=
> client goals (should the VoIP packet go first?). And no mention of
> airtime fairness or latency...
>
> Or am I missing something? Thanks.

No, they punted on these things in the design.

>
> Rich
> _______________________________________________
> Make-wifi-fast mailing list
> Make-wifi-fast@lists.bufferbloat.net
> https://lists.bufferbloat.net/listinfo/ma= ke-wifi-fast
_______________________________________________
Make-wifi-fast mailing list
M= ake-wifi-fast@lists.bufferbloat.net
https://lists.bufferbloat.net/listinfo/make-wif= i-fast
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