From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail2.tohojo.dk (mail2.tohojo.dk [77.235.48.147]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by huchra.bufferbloat.net (Postfix) with ESMTPS id 29D4321F231 for ; Mon, 27 Apr 2015 03:45:13 -0700 (PDT) X-Virus-Scanned: amavisd-new at mail2.tohojo.dk Received: by alrua-kau.kau.toke.dk (Postfix, from userid 1000) id 531F8C40134; Mon, 27 Apr 2015 12:45:05 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=toke.dk; s=201310; t=1430131506; bh=VLRdb4ZqjAPiN1ZIiCBeWs9v9GLW6YM/YJeiflfnfZw=; h=From:To:Cc:Subject:In-Reply-To:References:Date; b=iDjSUyA9HYrbHbTadscEqoucnlcNZtXR/lfqJMaIAvPJsuhDhCE788Ks02tmpeanZ FOt1OYVqSzA65gRYs/nWOZsmaDRTpQGxYpJ5G+6mOaMk4slxE98ppSpYcyOGMTjjhb Y5YT1/MNUMJUbYb/DERqEbXjBkVAQZJkgKoDG1Xs= From: =?utf-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= To: Neil Davies In-Reply-To: <72DB0260-F0DF-426F-A3F3-ECF5D8AF228F@pnsol.com> (Neil Davies's message of "Mon, 27 Apr 2015 10:54:51 +0100") References: <72DB0260-F0DF-426F-A3F3-ECF5D8AF228F@pnsol.com> Date: Mon, 27 Apr 2015 12:45:05 +0200 X-Clacks-Overhead: GNU Terry Pratchett Message-ID: <877fsx3l5a.fsf@toke.dk> MIME-Version: 1.0 Content-Type: text/plain Cc: bloat Subject: Re: [Bloat] Detecting bufferbloat from outside a node 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: Mon, 27 Apr 2015 10:45:42 -0000 Neil Davies writes: > Take a look at http://www.pnsol.com/publications.html, you may find > http://www.pnsol.com/public/PP-PNS-2009-02.pdf as a good starting > point. I've seen this referred on the list before (I assume by you ;)), but haven't really grok'ed it before. I like the delta-Q measure as a way of thinking about overall network performance; and there's definitely parallels to thinking about the end-to-end 'latency budget', which I also find quite instructive (I think I it picked up from Joe Touch at some point). How do you deal with the fact that loss and delay can be exchanged for each other (via retransmissions)? Also, which publication would you recommend if I'm interested in specifically how you 'Mathematically model behaviour and delta-Q' as you mention in that slide set? :) -Toke