From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sonic301-3.consmr.mail.bf2.yahoo.com (sonic301-3.consmr.mail.bf2.yahoo.com [74.6.129.42]) (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 907C03CB36 for ; Sun, 24 Mar 2019 16:15:46 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s2048; t=1553458545; bh=/8oSeGhzfLyw/3K5ZRX9gEnQwNY5USj1NwWaxRXExNw=; h=Date:From:Reply-To:To:Cc:In-Reply-To:References:Subject:From:Subject; b=HktHU4Gj+dIi298dGp8UxYtdu3bwPBK+bnMAAJv86RIHAe9QLtfGjZm2f9EZuJTKiPP7umvUZhrU0z1kJa1J1ZJzpXloM+SN2mKRVY/oL+YsP3+lPAg3BbWJZt7Ps/pWqimdMkbwwJ3V04kSZ+SnBN/z+IG53UDceMpPDVPM2CiAylflnmw+wSU9bv/rnIOkocGfEOfBnNgU97oxZBUdkqocIWdgDpRWroug11PxHklBK6dRre8WkHp6KcjN54GYlltUCZFDwoWqktFRLfOaAhWtbG/nqDlwrhBxM1dQOqgxcuA1/czMmLF6omYMaDE5EVnj1FiNz8EWFoAtqUpFBw== X-YMail-OSG: dcfbHJIVM1lA_RCcOTpEIs6JhyZDaZsE2JideKGfDZU3Z3VHvy2EufSxIwT.fSt CCCY_oLRgLp6fCDAqrRYvn9gFo9E.AOZZTCZ9bY7RLL6GUwyGQbLPy3KYu7umSCBta372GvqcT9. .gzqEQjJYDZlAOXX9JNcRz1SkVtWsa1bpp42jv7pECvGIJ3mIUyGJatC7mr8pa1ri4U37AWmRitT YOEf_fnOm.Xm.moSosQqnHJz6mQvssGeYfNL1e9cKC4N9hG3J9E00mPDQiKmQcmHU_nAtEax9DXm nswxr4qEf6hXhWR7oKzv53MowkdhKsUxl0.2vsg2XRhPZ9kXkZNOJfmzR.3JFBWEgYAxaSl7cljb C5fgyzHd09t1Az43w3gmBaWSYeD.AGzwA6.UuUDXEhGbQOUS4VsklyaYekvFgueA9S.poYb4Jj4T sR2nMWmcTBfYUa2kF1J2xRqPoU6t3bDbLm1uWN1hc.ynyLOHbHemjS3i9qf3z4ZW4qvh5jxlQz14 63xw.VXxlcmJgvtUtX73KrEZ3h6AqhIjSVDH7lqEeRqxz5eSWdJxlRoarLxWYZ_nSYibr_A9qM2H ZOSlZ8b_egvcW4Z83cVDgzXhER0uPYugt8h0WhexikR6.sxS25fVcoYMYXw33xf3k.9CpI5a.p82 9HSfQL._MtBf9jWbbrR6EnkKaIv_43Ih1DQgC_se4TMoadaLzYrvT8dNJDiIG3FiVXt0dCS5vK.I ZRggn3SjyptZN3rCV7DIB7XwyD4Suuz.vPFNIafTZdmqEwPknHly7h_2Bf7QZJlyahaawzt07Lfy 08_x048p9ju9vSOVLnZr4kj.nf6r6rbiu3QLMk70RPqT35d4ORPIMou_J8.6we_XpyCiU5crnbfg iysCB5RfvRYZ1M45bcqAr.V9ZsK_esAoeSGtRd5fjjgiFQ8BScih7nTYSB9T16fcOCn1Rq3ULTf1 Tb2nbCbHUdBwOz2K04Hk6U5z.XuYDp8Ox5KpsMfDcsC4OvN.YCoDml2U.nZM7iYZJ6pZkTCrTkPR sXWAQ0iQCW20r9ADur8lRtltg5kmEqdA.ft0TP6Do45S3mRX2r8vuC9X.hGVSqiGYt8SO4edp706 .OKXqKsNrmfNbyLI8IJSTEnV1.pUFCVkLdfHnTEf2bnKIJw-- Received: from sonic.gate.mail.ne1.yahoo.com by sonic301.consmr.mail.bf2.yahoo.com with HTTP; Sun, 24 Mar 2019 20:15:45 +0000 Date: Sun, 24 Mar 2019 20:15:15 +0000 (UTC) From: "alex.burr@ealdwulf.org.uk" Reply-To: "alex.burr@ealdwulf.org.uk" To: Bob Briscoe Cc: tsvwg IETF list , bloat Message-ID: <1872521079.10187924.1553458515947@mail.yahoo.com> In-Reply-To: <7e49b551-22e5-5d54-2a1c-69f53983d7e5@bobbriscoe.net> References: <1E80578D-A589-4CA0-9015-B03B63042355@gmx.de> <27FA673A-2C4C-4652-943F-33FAA1CF1E83@gmx.de> <1552669283.555112988@apps.rackspace.com> <7029DA80-8B83-4775-8261-A4ADD2CF34C7@akamai.com> <1552846034.909628287@apps.rackspace.com> <5458c216-07b9-5b06-a381-326de49b53e0@bobbriscoe.net> <7e49b551-22e5-5d54-2a1c-69f53983d7e5@bobbriscoe.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Mailer: WebService/1.1.13212 YMailNorrin Mozilla/5.0 (X11; Ubuntu; Linux x86_64; rv:65.0) Gecko/20100101 Firefox/65.0 X-Mailman-Approved-At: Wed, 27 Mar 2019 14:44:32 -0400 Subject: Re: [Bloat] [Ecn-sane] [iccrg] Fwd: [tcpPrague] Implementation and experimentation of TCP Prague/L4S hackaton at IETF104 X-BeenThere: bloat@lists.bufferbloat.net X-Mailman-Version: 2.1.20 Precedence: list List-Id: General list for discussing Bufferbloat List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 24 Mar 2019 20:15:46 -0000 Hi Bob, I note that all the non-dependent claims of US20170019343A1 (claims 1,14,22= ) seem to assume use of the proportional-integral controller (Note, I am no= t a lawyer, and especially not a patent lawyer). In Appendix B of draft-bri= scoe-tsvwg-aqm-dualq-coupled, an alternate algorithm 'Curvy RED' seems to r= eplace PI, but it is noted that 'the Curvy RED algorithm has not been maint= ained to the same degree as the DualPI2 algorithm '. Can you comment on whether the Curvy RED algorithm could form a non-patent-= encumbered dualq? In particular: =C2=A0- Why wasn't curvy red further developed? Was it found to contain som= e deficiency? Are you intending to present it as an alternative? =C2=A0- Does Curvy RED actually completely replace PI? =C2=A0- Can we have reasonable assurance that no patents will surface cover= ing Curvy RED? Thanks, Alex On Wednesday, March 20, 2019, 11:29:38 PM GMT, Bob Briscoe wrote:=20 1/ In 2016, I arranged for the hire of a patent attorney to undertake the u= nusual step of filing a third party observation with the European Patent Of= fice. This went through Al-Lu's patent application claim by claim pointing = to prior art and giving the patent examiner all the arguments to reject eac= h claim. However, the examiner chose to take very little note of it, which = was disappointing and costly for us. The main prior art is: =C2=A0=C2=A0=C2=A0 Gibbens, R.J. & Kelly, F.P., "On Packet Marking at Prior= ity Queues," IEEE Transactions on Automatic Control 47(6):1016--1020 (June = 2002) The guys named as inventors in AL-Lu's filing published a paper on PI2 with= me, in which we included a citation of this Gibbens paper as inspiration f= or the coupling. The Gibbens paper was already cited as background by other= patents, so the EPO has it in their citation index. The coupling was also based on my prior research with Mirja before I starte= d working with the guys from Al-Lu in the RITE European Collaborative proje= ct. we had to go through a few rejections, but Mirja and I finally got this= work published in 2014=C2=A0 - still before the priority date of the Al-Lu= patent application: =C2=A0=C2=A0=C2=A0 K=C3=BChlewind, M., Wagner, D.P., Espinosa, J.M.R. & Bri= scoe, B., "Using Data Center TCP (DCTCP) in the Internet," In: Proc. Third = IEEE Globecom Workshop on Telecommunications Standards: From Research to St= andards pp.583-588 (December 2014) 2/ The only claim that I could not find prior art for (in the original EU f= iling) was a very specific claim about using a square root for the coupling= . The Linux implementation runs this the other way round so that it only ha= s to do a squaring. So I figured we were safe from that. However, until just now, I had not noticed that Al-Lu has retrospectively r= e-written the claims in the US patent and in the EU patent application to c= laim this the other way round - as a squaring. And to claim the two random = number trick. Both restructuring to use a squaring and the two random numbe= r trick were definitely my ideas (while working for BT in a collaboration w= ith Al-Lu). I have emails to prove this (from memory they were actually bot= h in the same email). This is important, because a patent has to be about m= echanism, not algorithm. 3/ This is a positive development. It means this patent is on very shaky le= gal ground. I have been trying to put pressure on Nokia to license this roy= alty free. But now I see what they have done, I am going to have to get a d= ifferent type of legal advice.=20