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 ) 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 ; 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: From: Melvin Carvalho To: kjj Content-Type: multipart/alternative; boundary=089e015386f08b565f04ea862a1b X-Spam-Score: -0.6 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. 0.0 URIBL_BLOCKED ADMINISTRATOR NOTICE: The query to URIBL was blocked. See http://wiki.apache.org/spamassassin/DnsBlocklists#dnsbl-block for more information. [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 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: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-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 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



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<= br> 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. =A0An iterated FSM is not a suitable
simulation of the bitcoin system. =A0The 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. =A0They handwave the issue by assuming a total 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= .

Greg said he'd like to run some simulations, and I'm thinking about= it
too. =A0Unfortunately, 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. =A0It needs to be able to simulate an attacker that<= br> owns varying fractions of the network, and make decisions based only on
what the attacker actually knows. =A0It needs to be able to simulate this "attack" and should be generic enough to be easily modified for o= ther
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. =A0If 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=3D324413.= msg3495663#msg3495663

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.
=A0



---------------------------------------------------------------------------= ---
November Webinars for C, C++, Fortran Developers
Accelerate application performance with scalable programming models. Explor= e
techniques for threading, error checking, porting, and tuning. Get the most=
from the latest Intel processors and coprocessors. See abstracts and regist= er
http://pubads.g.doubleclick.net/gam= pad/clk?id=3D60136231&iu=3D/4140/ostg.clktrk
_______________________________________________
Bitcoin-development mailing list
Bitcoin-develo= pment@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bitcoin-de= velopment

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