Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from <melvincarvalho@gmail.com>) id 1Ve7ft-0001Sd-Ss for Bitcoin-development@lists.sourceforge.net; Wed, 06 Nov 2013 18:17:53 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.223.179 as permitted sender) client-ip=209.85.223.179; envelope-from=melvincarvalho@gmail.com; helo=mail-ie0-f179.google.com; Received: from mail-ie0-f179.google.com ([209.85.223.179]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1Ve7fs-0007Mf-KK for Bitcoin-development@lists.sourceforge.net; Wed, 06 Nov 2013 18:17:53 +0000 Received: by mail-ie0-f179.google.com with SMTP id aq17so18565895iec.10 for <Bitcoin-development@lists.sourceforge.net>; Wed, 06 Nov 2013 10:17:47 -0800 (PST) MIME-Version: 1.0 X-Received: by 10.50.178.202 with SMTP id da10mr3490880igc.44.1383761867113; Wed, 06 Nov 2013 10:17:47 -0800 (PST) Received: by 10.64.17.167 with HTTP; Wed, 6 Nov 2013 10:17:46 -0800 (PST) In-Reply-To: <5279D49D.5050807@jerviss.org> References: <5279D49D.5050807@jerviss.org> Date: Wed, 6 Nov 2013 19:17:46 +0100 Message-ID: <CAKaEYhLpr24+7B0w410S7XdGgyOU4vsv07uv2e6yvYNKV8ZQJQ@mail.gmail.com> From: Melvin Carvalho <melvincarvalho@gmail.com> To: kjj <bitcoin-devel@jerviss.org> Content-Type: multipart/alternative; boundary=089e015386f08b565f04ea862a1b X-Spam-Score: -0.6 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. 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[URIs: doubleclick.net] -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (melvincarvalho[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature X-Headers-End: 1Ve7fs-0007Mf-KK Cc: Bitcoin Dev <Bitcoin-development@lists.sourceforge.net> Subject: Re: [Bitcoin-development] we can all relax now X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: <bitcoin-development.lists.sourceforge.net> List-Unsubscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>, <mailto:bitcoin-development-request@lists.sourceforge.net?subject=unsubscribe> List-Archive: <http://sourceforge.net/mailarchive/forum.php?forum_name=bitcoin-development> List-Post: <mailto:bitcoin-development@lists.sourceforge.net> List-Help: <mailto:bitcoin-development-request@lists.sourceforge.net?subject=help> List-Subscribe: <https://lists.sourceforge.net/lists/listinfo/bitcoin-development>, <mailto:bitcoin-development-request@lists.sourceforge.net?subject=subscribe> X-List-Received-Date: Wed, 06 Nov 2013 18:17:54 -0000 --089e015386f08b565f04ea862a1b Content-Type: text/plain; charset=ISO-8859-1 On 6 November 2013 06:33, kjj <bitcoin-devel@jerviss.org> wrote: > One of the things that really gets me going is when someone devises a > model, tests it against itself, and then pretends that they've learned > something about the real world. > > Naturally, the Selfish Mining paper is exactly this sort of nonsense. > Their model is one with no latency, and one where the attacker has total > visibility across the network. An iterated FSM is not a suitable > simulation of the bitcoin system. The bitcoin network does not have > states, and to the extent that you can pretend that we do, you can't > simulate transitions between them with static probabilities. > > The authors understand this deep down inside, even though they didn't > work out the implications. They handwave the issue by assuming a total > sybil attack, and in true academic spirit, they don't realize that the > condition necessary for the attack is far, far worse than the attack > itself. > > Greg said he'd like to run some simulations, and I'm thinking about it > too. Unfortunately, he is busy all week, and I'm lazy (and also busy > for most of tomorrow). > > If neither of us get to it first, I'm willing to pitch in 1 BTC as a > bounty for building a general bitcoin network simulator framework. The > simulator should be able to account for latency between nodes, and > ideally within a node. It needs to be able to simulate an attacker that > owns varying fractions of the network, and make decisions based only on > what the attacker actually knows. It needs to be able to simulate this > "attack" and should be generic enough to be easily modified for other > crazy schemes. > > (Bounty offer is serious, but expires in one year [based on the earliest > timestamp that my mail server puts on this email], and /may/ be subject > to change if the price on any reputable exchange breaks 1000 USD per BTC > in that period.) > > Basically, the lack of a decent network simulator is what allowed this > paper to get press. If the author had been able to see the importance > of the stuff he was ignoring, we wouldn't be wasting so much time > correcting him (and sadly the reporters that have no way to check his > claims). > > https://bitcointalk.org/index.php?topic=324413.msg3495663#msg3495663 > Thanks for posting this bounty. I'm interested in working on it, and will give it a try. I also have some other commitments, so I suspect you guys will finish it first tho... but if not, I'll post details of the simulator. > > > > > ------------------------------------------------------------------------------ > November Webinars for C, C++, Fortran Developers > Accelerate application performance with scalable programming models. > Explore > techniques for threading, error checking, porting, and tuning. Get the most > from the latest Intel processors and coprocessors. See abstracts and > register > http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > --089e015386f08b565f04ea862a1b Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr"><br><div class=3D"gmail_extra"><br><br><div class=3D"gmail= _quote">On 6 November 2013 06:33, kjj <span dir=3D"ltr"><<a href=3D"mail= to:bitcoin-devel@jerviss.org" target=3D"_blank">bitcoin-devel@jerviss.org</= a>></span> wrote:<br> <blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p= x #ccc solid;padding-left:1ex">One of the things that really gets me going = is when someone devises a<br> model, tests it against itself, and then pretends that they've learned<= br> something about the real world.<br> <br> Naturally, the Selfish Mining paper is exactly this sort of nonsense.<br> Their model is one with no latency, and one where the attacker has total<br= > visibility across the network. =A0An iterated FSM is not a suitable<br> simulation of the bitcoin system. =A0The bitcoin network does not have<br> states, and to the extent that you can pretend that we do, you can't<br= > simulate transitions between them with static probabilities.<br> <br> The authors understand this deep down inside, even though they didn't<b= r> work out the implications. =A0They handwave the issue by assuming a total<b= r> sybil attack, and in true academic spirit, they don't realize that the<= br> condition necessary for the attack is far, far worse than the attack itself= .<br> <br> Greg said he'd like to run some simulations, and I'm thinking about= it<br> too. =A0Unfortunately, he is busy all week, and I'm lazy (and also busy= <br> for most of tomorrow).<br> <br> If neither of us get to it first, I'm willing to pitch in 1 BTC as a<br= > bounty for building a general bitcoin network simulator framework. The<br> simulator should be able to account for latency between nodes, and<br> ideally within a node. =A0It needs to be able to simulate an attacker that<= br> owns varying fractions of the network, and make decisions based only on<br> what the attacker actually knows. =A0It needs to be able to simulate this<b= r> "attack" and should be generic enough to be easily modified for o= ther<br> crazy schemes.<br> <br> (Bounty offer is serious, but expires in one year [based on the earliest<br= > timestamp that my mail server puts on this email], and /may/ be subject<br> to change if the price on any reputable exchange breaks 1000 USD per BTC<br= > in that period.)<br> <br> Basically, the lack of a decent network simulator is what allowed this<br> paper to get press. =A0If the author had been able to see the importance<br= > of the stuff he was ignoring, we wouldn't be wasting so much time<br> correcting him (and sadly the reporters that have no way to check his<br> claims).<br> <br> <a href=3D"https://bitcointalk.org/index.php?topic=3D324413.msg3495663#msg3= 495663" target=3D"_blank">https://bitcointalk.org/index.php?topic=3D324413.= msg3495663#msg3495663</a><br></blockquote><div><br></div><div>Thanks for po= sting this bounty.=A0 I'm interested in working on it, and will give it= a try.=A0 I also have some other commitments, so I suspect you guys will f= inish it first tho... but if not, I'll post details of the simulator.<b= r> </div><div>=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0= .8ex;border-left:1px #ccc solid;padding-left:1ex"> <br> <br> <br> ---------------------------------------------------------------------------= ---<br> November Webinars for C, C++, Fortran Developers<br> Accelerate application performance with scalable programming models. Explor= e<br> techniques for threading, error checking, porting, and tuning. Get the most= <br> from the latest Intel processors and coprocessors. See abstracts and regist= er<br> <a href=3D"http://pubads.g.doubleclick.net/gampad/clk?id=3D60136231&iu= =3D/4140/ostg.clktrk" target=3D"_blank">http://pubads.g.doubleclick.net/gam= pad/clk?id=3D60136231&iu=3D/4140/ostg.clktrk</a><br> _______________________________________________<br> Bitcoin-development mailing list<br> <a href=3D"mailto:Bitcoin-development@lists.sourceforge.net">Bitcoin-develo= pment@lists.sourceforge.net</a><br> <a href=3D"https://lists.sourceforge.net/lists/listinfo/bitcoin-development= " target=3D"_blank">https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment</a><br> </blockquote></div><br></div></div> --089e015386f08b565f04ea862a1b--