Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Uywmc-0005n6-6E for bitcoin-development@lists.sourceforge.net; Tue, 16 Jul 2013 04:22:38 +0000 Received-SPF: pass (sog-mx-4.v43.ch3.sourceforge.com: domain of coinlab.com designates 209.85.216.172 as permitted sender) client-ip=209.85.216.172; envelope-from=peter@coinlab.com; helo=mail-qc0-f172.google.com; Received: from mail-qc0-f172.google.com ([209.85.216.172]) by sog-mx-4.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1Uywma-00015Q-Bl for bitcoin-development@lists.sourceforge.net; Tue, 16 Jul 2013 04:22:38 +0000 Received: by mail-qc0-f172.google.com with SMTP id j10so129204qcx.17 for ; Mon, 15 Jul 2013 21:22:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:x-gm-message-state; bh=6woqdcp1/74XzHfDWiK24u8e8HywJhSECqykRatbAL4=; b=GJZYrofDJ2AsZrbhK+mrk72vyfbRDk+BDOHDz3ZtgsyQjROS6JRAqnbZI4yORZZXYn nyFkEhaXbvTclwZUn+uRgf5Gp6C0mv3U03qPLrWXhYzUl2r8K8GInCpWlrVKZ9guCd7p rIdCVhO6hhpkKQy7wU5nK0SGY7rTJue5MhNysHY4tErjCiHx9u0cJIhY53+0RBBxviZO tex8D4npD1cn+2vWseYyQudDYzRP+A1CySRv76WhkbEXLkJpNFWrtLqHa9uCztvOFBFD STLh1+tG1AXCcsS8EuamLN5RHFqqm7Gaxhca9sotZAJsYXL/2B4xBSsC2AsisflPPpHi 7Zow== X-Received: by 10.49.106.40 with SMTP id gr8mr53446636qeb.84.1373946883404; Mon, 15 Jul 2013 20:54:43 -0700 (PDT) MIME-Version: 1.0 Received: by 10.49.39.137 with HTTP; Mon, 15 Jul 2013 20:54:23 -0700 (PDT) In-Reply-To: <20130715202909.GA9286@petertodd.org> References: <20130705140140.GA23949@netbook.cypherspace.org> <20130712131815.GA18716@petertodd.org> <20130715095107.GA8828@savin> <20130715202909.GA9286@petertodd.org> From: Peter Vessenes Date: Mon, 15 Jul 2013 21:54:23 -0600 Message-ID: To: Peter Todd Content-Type: multipart/alternative; boundary=047d7b675db0ecf92d04e198ef18 X-Gm-Message-State: ALoCoQmX7SZG9KrespGI5CbsE8Q16y5pxuNCATiZAwDgs/m45b/2IwbjF96bkN24V3tpH9308qLR X-Spam-Score: -0.5 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message X-Headers-End: 1Uywma-00015Q-Bl Cc: Bitcoin-Dev Subject: Re: [Bitcoin-development] libzerocoin released, what about a zerocoin-only alt-coin with either-or mining 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: Tue, 16 Jul 2013 04:22:38 -0000 --047d7b675db0ecf92d04e198ef18 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable I'm at the Aspen Institute right now talking about Bitcoin and I mentioned the perils of starting an alt-chain based on proof of work that pool operators might attack; funny synchronicity! Peter On Mon, Jul 15, 2013 at 2:29 PM, Peter Todd wrote: > On Mon, Jul 15, 2013 at 03:05:52PM +0200, Jorge Tim=F3n wrote: > > One way sacrifice (btc to zerocoin) is a non-issue since there's no > > modification required for bitcoin and you can't do anything to prevent > > it anyway. > > The controversial thing is sacrificing something outside bitcoin's > > chain and new btc appearing. > > Which is why I'm not proposing that. > > > On merged mining. It is true that "merged attacking" the other chain > > is free, but it is still more profitable to just follow the rules and > > mine the other coin!! > > If someone considers that something he can sell in a market for btc is > > "negative value"...well, he's just dammed stupid. Proof of work is > > designed for rational actors, if you stop assuming miners are more or > > less rational everything falls apart. It is possible that the "extra > > value" is too little for some miners to bother. But the extra costs of > > validating something else are so little compared to chance-hashing > > that miners not merged mining namecoin right now are just stupid > > (irrational agents). You can merged mine and sell for btc right away. > > You are assuming value is the same for everyone - it's not. > > If I mine in a jurisdiction where zerocoin is banned, and the blocks I > mine are public, the value of zerocoin blocks to me are at best zero. > Equally it would be easy for the local authorities to ask that I merge > mine zerocoin blocks to attack the chain - it doesn't cost me anything > so what's the harm? I may even choose to do so to preserve the value of > the coins I can mine legally - alt-coins are competition. > > Incedentally keep in mind it is likely that in the future pools will not > allow miners to modify the work units they receive in any way as a means > of combating block-withholding fraud; there may not be very many people > willing or able to honestly merge-mine any given chain. > > Proof-of-sacrifice can be done in a way that is opaque to the master > blockchain by creating txouts that look no different from any other > txout. Hopefully not required, but it would be a good strategy against > censorship of sacrifice-based chains. > > > On prime proof of work...for me it's interseting only because it's > > moving towards SCIP-based mining but that should be the goal. Like > > Mark said, "let's cure cancer" while mining. That would end all > > "mining is wasteful" arguments about this great security system. This > > would make Ripple's consensus mechanism less attractive. People > > talking about new scrypts harder to ASIC-mine when that's the elephant > > in the room... > > Sorry, I'm going off-topic. > > SCIP-based merged mining for the win. > > SCIP is for now a dream. Give it a few more years and see how the > technology shakes out. > > -- > 'peter'[:-1]@petertodd.org > 00000000000000582cc323897a582e9368a5c3dfbcdcf73e78b261703e1bd1ba > --=20 ------------------------------ [image: CoinLab Logo]PETER VESSENES CEO *peter@coinlab.com * / 206.486.6856 / SKYPE: vessenes 900 Winslow Way East / SUITE 100 / Bainbridge Island, WA 98110 --047d7b675db0ecf92d04e198ef18 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable
I'm at the Aspen Institute right now talking about Bit= coin and I mentioned the perils of starting an alt-chain based on proof of = work that pool operators might attack; funny synchronicity!

Peter


On Mon, Jul 15, 2013 at 2:29 PM, Peter Todd <= pete@petertodd.org<= /a>> wrote:
On Mon, Jul 15, 2013 at 03= :05:52PM +0200, Jorge Tim=F3n wrote:
> One way sacrifice (btc to zerocoin) is a non-issue since there's n= o
> modification required for bitcoin and you can't do anything to pre= vent
> it anyway.
> The controversial thing is sacrificing something outside bitcoin's=
> chain and new btc appearing.

Which is why I'm not proposing that.

> On merged mining. It is true that "merged attacking" the oth= er chain
> is free, but it is still more profitable to just follow the rules and<= br> > mine the other coin!!
> If someone considers that something he can sell in a market for btc is=
> "negative value"...well, he's just dammed stupid. Proof = of work is
> designed for rational actors, if you stop assuming miners are more or<= br> > less rational everything falls apart. It is possible that the "ex= tra
> value" is too little for some miners to bother. But the extra cos= ts of
> validating something else are so little compared to chance-hashing
> that miners not merged mining namecoin right now are just stupid
> (irrational agents). You can merged mine and sell for btc right away.<= br>
You are assuming value is the same for everyone - it's not.

If I mine in a jurisdiction where zerocoin is banned, and the blocks I
mine are public, the value of zerocoin blocks to me are at best zero.
Equally it would be easy for the local authorities to ask that I merge
mine zerocoin blocks to attack the chain - it doesn't cost me anything<= br> so what's the harm? I may even choose to do so to preserve the value of=
the coins I can mine legally - alt-coins are competition.

Incedentally keep in mind it is likely that in the future pools will not allow miners to modify the work units they receive in any way as a means of combating block-withholding fraud; there may not be very many people
willing or able to honestly merge-mine any given chain.

Proof-of-sacrifice can be done in a way that is opaque to the master
blockchain by creating txouts that look no different from any other
txout. Hopefully not required, but it would be a good strategy against
censorship of sacrifice-based chains.

> On prime proof of work...for me it's interseting only because it&#= 39;s
> moving towards SCIP-based mining but that should be the goal. Like
> Mark said, "let's cure cancer" while mining. That would = end all
> "mining is wasteful" arguments about this great security sys= tem. This
> would make Ripple's consensus mechanism less attractive. People > talking about new scrypts harder to ASIC-mine when that's the elep= hant
> in the room...
> Sorry, I'm going off-topic.
> SCIP-based merged mining for the win.

SCIP is for now a dream. Give it a few more years and see how the
technology shakes out.

--
'peter'[:-1]@pet= ertodd.org
00000000000000582cc323897a582e9368a5c3dfbcdcf73e78b261703e1bd1ba



--

3D=PETER=A0VESSE= NES=A0
CEO

peter@coinlab.com=A0=A0/=A0=A0206.486.6856 = =A0/=A0SKYPE:=A0vessenes=A0
900 Winslow Way East / SUITE 100 =A0/ =A0Bainbridge Island, WA 98110

--047d7b675db0ecf92d04e198ef18--