From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-vn0-x22a.google.com (mail-vn0-x22a.google.com [IPv6:2607:f8b0:400c:c0f::22a]) (using TLSv1 with cipher RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by huchra.bufferbloat.net (Postfix) with ESMTPS id 6BD5321F205 for ; Tue, 28 Apr 2015 05:09:24 -0700 (PDT) Received: by vnbf129 with SMTP id f129so15727245vnb.9 for ; Tue, 28 Apr 2015 05:09:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=content-type:mime-version:subject:from:in-reply-to:date:cc :content-transfer-encoding:message-id:references:to; bh=eBpapULxy6Bt7UHJemt2ZiGKRV6zY57vYmplFK4ZUZk=; b=rkBploLUnaqIN2iKQSWPLEMNl4DQbhwgzBrhtCmcHeEpZj00flkNgS3U838ORZBfxR Oplt5sDeGrXXk25lXLi1HBNeHT7McQLs0zROOn5w3RM45wALQPMlxW7NbHI8ipfjQHCq /y4iuKjUxf6ldnh78O8DJvAMT3PNgkdujWQkJgXZ0sjaBZ93D+gnafEhViLDfQ1FDa9n EoAk1Y//sfpzyosw7HmJ/P+ihKTS9JGTJqZDl25ic6kYj38KQntYL1NNEs/zDmWCdEFe 17dVEMd5eJFXZbxopouviIIt1PB6Ts1D+Yuu+XD4ww7TCu96J0uuQXgB1Y9/p9TP47NT eWNg== X-Received: by 10.52.0.228 with SMTP id 4mr35170536vdh.25.1430222963768; Tue, 28 Apr 2015 05:09:23 -0700 (PDT) Received: from richs-mbp-11940.home.lan ([70.16.99.228]) by mx.google.com with ESMTPSA id s2sm31261397vdh.8.2015.04.28.05.09.22 (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 28 Apr 2015 05:09:22 -0700 (PDT) Content-Type: text/plain; charset=windows-1252 Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) From: Rich Brown In-Reply-To: <07C4C7B3-80BA-4106-9263-E86E652FC5AC@gmx.de> Date: Tue, 28 Apr 2015 08:09:20 -0400 Content-Transfer-Encoding: quoted-printable Message-Id: <3A7A1CB6-CB2C-40D3-AF9D-D7C67C534710@gmail.com> References: <1429717468.18561.90.camel@edumazet-glaptop2.roam.corp.google.com> <5537CDB7.60301@orange.com> <1429722979.18561.112.camel@edumazet-glaptop2.roam.corp.google.com> <5537DA20.1090008@orange.com> <5537DE4D.8090100@orange.com> <553882D7.4020301@orange.com> <1429771718.22254.32.camel@edumazet-glaptop2.roam.corp.google.com> <6C0D04CF-53AA-4D18-A4E4-B746AF6487C7@gmx.de> <87wq123p5r.fsf@toke.dk> <2288B614-B415-4017-A842-76E8F5DFDE4C@gmx.de> <553B06CE.1050209@superduper.net> <14ceed3c818.27f7.e972a4f4d859b00521b2b659602cb2f9@superduper.net> <0C930D43-A05B-48E2-BC01-792CAA72CAD1@gmx.de> <1D70AD75-F177-4146-A4D6-2FD6DB408B63@gmx.de> <07C4C7B3-80BA-4106-9263-E86E652FC5AC@gmx.de> To: Sebastian Moeller X-Mailer: Apple Mail (2.1878.6) Cc: bloat Subject: Re: [Bloat] DSLReports Speed Test has latency measurement built-in X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.13 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 28 Apr 2015 12:09:53 -0000 On Apr 28, 2015, at 4:38 AM, Sebastian Moeller wrote: > Well, what I want to see is a study, preferably psychophysics = not modeling ;), showing the different latency =93tolerances=94 of = humans. I am certain that humans can adjust to even dozens of seconds = de;ays if need be, but the goal should be fluent and seamless = conversation not interleaved monologues. Thanks for giving a bound for = jitter, do you have any reference for perceptional jitter thresholds or = some such? An anecdote (we don't need no stinkin' studies :-) I frequently listen to the same interview on NPR twice: first at say, = 6:20 am when the news is breaking, and then at the 8:20am rebroadcast. The first interview is live, sometimes with significant satellite delays = between the two parties. The sound quality is fine. But the pauses = between question and answer (waiting for the satellite propagation) = sometimes make the responder seem a little "slow witted" - as if they = have to struggle to compose their response. But the rebroadcast gets "tuned up" by NPR audio folks, and those pauses = get edited out. I was amazed how the conversation takes on a completely = different flavor: any negative impression goes away without that = latency. So, what lesson do I learn from this? Pure latency *does* affect the = nature of the conversation - it may not be fluent and seamless if = there's a satellite link's worth of latency involved.=20 Although not being exhibited in this case, I can believe that jitter = plays worse havoc on a conversation. I'll also bet that induced latency = is a good proxy for jitter. Rich=