From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x234.google.com (mail-qt0-x234.google.com [IPv6:2607:f8b0:400d:c0d::234]) (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 C10573CB35 for ; Mon, 27 Aug 2018 22:14:06 -0400 (EDT) Received: by mail-qt0-x234.google.com with SMTP id j7-v6so64056qtp.2 for ; Mon, 27 Aug 2018 19:14:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=8oQV9Pwr+jJzIAmu6oK75e+1FW1HTEMSyU1piik87N4=; b=BvV4ccs/L9L15kwy3mPXBeLuNr6F/E6K2pgCqTh3aJgfXZ741OKKMbIOCEfSswNuRy ZC6MWSy4twlXNiFTDQsxC1LKplPsvWCTk4Aum76fo0s5l6wtzkCOZstaQ/AfNdhI6ARX VgOtkiFgkBGW5/ItJivgkm8of+JM1VbrHVODCNhiCRKRJBDsDqCHvXdHy7qSYmfMZpTm haUCFmynWrSujBkFqxalDYVUO7esR0ccAqDSiuTHk524R17Xd/s8HwAFZ+si/1F/XQ6i BkDEMrrpo067gPzdm2M+wv4Eb8lkhWsnf4ya6vgbBiWqRqWb//hzsf9oGpOtXzFWjTTR 09LA== 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:content-transfer-encoding; bh=8oQV9Pwr+jJzIAmu6oK75e+1FW1HTEMSyU1piik87N4=; b=MXdYfI7rAb+tmxNosvphw/2VbauT2nWB1IAKsk2IAhTbHom/1Hgi+2xCTtMgSDzBkf WrtLwD1RknvGHmK6u/LUPcjIhuJtsmwpnHk7vojpY2T66RrEDybG/6j5VArHylln+Ikp tugAGdo4/NLKfPL9Rx6eDPQNFI/tcuQKBgPWe8VOC0mpaRuS+QnxVPNTPNkteAzCVN5t mbxbz+kePr75Jl2f08epSQwFWs3umYx4YhrWH3IkqJTIUEMC0SOZmV65AmZ9Hh52ZMbf 2uNA4i26MwmgjpbelgCqeGnpnStVQx1b3YFp+LA8jT5AtimDpxtO69ZnIP71DjxcpwAf nxdQ== X-Gm-Message-State: APzg51CLuyhJx0fO/EvjSo3A2B/uz+Ng1OiPtCkH5tF65FdbOH3XpH0i 37I9emYLvhqXsJusxeBeR/zY7QNB4MZr+M2vz+hPzQ== X-Google-Smtp-Source: ANB0VdZIuzU+VgZ7FW/KofmGrbsSvv/w1EhoDt+yU15aynnyaMMBft9OhHQt+mUMYSv1iQw1aCaKbzwrTL2WvOuKTEA= X-Received: by 2002:a0c:bb95:: with SMTP id i21-v6mr16645731qvg.158.1535422446330; Mon, 27 Aug 2018 19:14:06 -0700 (PDT) MIME-Version: 1.0 References: <1535286372.35121837@apps.rackspace.com> <2282D31E-CBEF-4B42-A6A6-4D6394EE0DF7@gmail.com> In-Reply-To: From: Dave Taht Date: Mon, 27 Aug 2018 19:14:51 -0700 Message-ID: To: Bob McMahon Cc: David Lang , Make-Wifi-fast Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Subject: [Make-wifi-fast] deep wifi X-BeenThere: make-wifi-fast@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Aug 2018 02:14:06 -0000 taking all the other lists off the cc. and changing the thread title to something else that's less depressing. On Mon, Aug 27, 2018 at 6:56 PM Bob McMahon wrot= e: > > Hmm, not sure I understand the distinction. CTS per the AP informs thos= e other transmitters to stay quiet per the CTS NAV. I may be misunderstand= ing things. Thanks for the continued discussions. It helps to better thor= oughly understand the issues. > > Bob > > On Mon, Aug 27, 2018, 6:52 PM David Lang wrote: >> >> On Mon, 27 Aug 2018, Bob McMahon wrote: >> >> > I thought that RTS/CTS would handle the case of hidden nodes, i.e. a d= evice >> > that fails to successfully transmit can resort to RTS/CTS to get the >> > receiver to reserve time for it. Also, lack of a RX ack seems ok to >> > trigger MAC level retransmits. >> >> the problem isn't getting the receiver to reserve time for it, it's gett= ing the >> other transmitter(s) to not step on it when it transmits. Those other >> transmitters may belong to different people, sharing a channel with your= system >> and nothing else. >> >> David Lang >> >> > It seems the LBT bug is the collision avoidance overheads when it isn'= t >> > needed, i.e. no other energy would cause the RX PHY to fail its decode= and >> > the EDCA backoffs had no benefit, stochastic or otherwise. Optimizin= g >> > that out is said to be not possible from local information only and pe= r >> > "shared" spectrum. >> > >> > Bob >> > >> > >> > On Mon, Aug 27, 2018 at 3:33 PM David Lang wrote: >> > >> >> On Mon, 27 Aug 2018, Jonathan Morton wrote: >> >> >> >>> So in practice, it's easier to measure SNR at the receiver, or >> >> indirectly by >> >>> observing packet loss by dint of missing acknowledgements returned t= o >> >> the >> >>> transmitter. >> >> >> >> Also, there may be other transmitters that the recipient of the packe= ts >> >> can hear >> >> that you cannot hear, so it's not possible to detect colliding >> >> transmissions >> >> directly in all cases. >> >> >> >> This is another trap that digital/wired people fall into that doesn't >> >> really >> >> apply in the analog/radio world. >> >> >> >> David Lang >> >> >> > > > _______________________________________________ > Make-wifi-fast mailing list > Make-wifi-fast@lists.bufferbloat.net > https://lists.bufferbloat.net/listinfo/make-wifi-fast --=20 Dave T=C3=A4ht CEO, TekLibre, LLC http://www.teklibre.com Tel: 1-669-226-2619