From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id CD85998C for ; Thu, 6 Apr 2017 02:39:09 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-it0-f48.google.com (mail-it0-f48.google.com [209.85.214.48]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 3FB6AF0 for ; Thu, 6 Apr 2017 02:39:09 +0000 (UTC) Received: by mail-it0-f48.google.com with SMTP id e75so93866919itd.1 for ; Wed, 05 Apr 2017 19:39:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bittorrent-com.20150623.gappssmtp.com; s=20150623; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc; bh=a6Z94EjCqEXNewByOz36bfcD9h6Bh9J9WH4d6SQp6Mc=; b=jchjG1C+ekMLnMjHDxoMw1AsFV3+gULXU7ZT4XlwhcoNSpbUiNl2oNZVX8zp/b/ZYs /t9C236sEOks91j/BUGiHYaPwFbw+ia77jCTxMAoYiW59qNAHrXAs+BnF1s81ezNhetG 3AqHOAPfLdXUdQWRbXeAOYnXVWyPIVpczQyT5YloNlPi4IJObMOkrKTwLO1FLijjNk+4 N6MPm6c6YCvfSQOtG3llNLhw80ccOg8eCsmONWDB892aBSetgzcHUAXE1lVLXm8J0JnI c2FOr+h13tFcx9CXt5/1nHmZp3juIe9ZGghCsRkpAWYko6/F8zLMpNiDO10InRLoh0a+ gZNQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=a6Z94EjCqEXNewByOz36bfcD9h6Bh9J9WH4d6SQp6Mc=; b=UaSBZa8DFiTjS1xiXQOGiOgs0lhH40FPmJZ1/PVUzszGldGLGkbHv1r8/Kdw7jBCvo DdiCEYt8RIDtxPf8UjSfksvLljHaZv0ulZZcIKwQ5KR5Xs0qMiY0nwcVbAb0eMD1b41u GeF+8tnKt34oEhvFQI8S2e+ZUaZg+jGeJe544EpFyCxIZhqcjj3bBCm+InZGufFAG22v qVmuD+qu3u5EVDPAzavI3vcRaTFrQkMlY5cak18FiLUyI4v+3yND9RjBOGxCmDijGg1F J92pMG76qof05UauJWz4B+2UADCi2oCi1NhyLuVT2S1T2GXRsGT5GdX+qI2pU9kXwLFZ JhiA== X-Gm-Message-State: AFeK/H0RSORDXgFpQbgVd88VZV8Sqf07kwmWIy0sjHkHe9LYDz2Y00ym XrcGhZizzfzqyX6I8v2HJgut0QUXDgA1 X-Received: by 10.36.107.214 with SMTP id v205mr24323755itc.65.1491446348638; Wed, 05 Apr 2017 19:39:08 -0700 (PDT) MIME-Version: 1.0 Received: by 10.36.184.70 with HTTP; Wed, 5 Apr 2017 19:39:08 -0700 (PDT) In-Reply-To: <20170406023123.GA1071@savin.petertodd.org> References: <20170406023123.GA1071@savin.petertodd.org> From: Bram Cohen Date: Wed, 5 Apr 2017 19:39:08 -0700 Message-ID: To: Peter Todd , Bitcoin Protocol Discussion Content-Type: multipart/alternative; boundary=001a114ac8f6d03947054c7669bc X-Spam-Status: No, score=-1.4 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, HTML_MESSAGE, RCVD_IN_DNSWL_NONE, RCVD_IN_SORBS_SPAM autolearn=no version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Subject: Re: [bitcoin-dev] BIP proposal: Inhibiting a covert attack on the Bitcoin POW function X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 06 Apr 2017 02:39:09 -0000 --001a114ac8f6d03947054c7669bc Content-Type: text/plain; charset=UTF-8 On Wed, Apr 5, 2017 at 7:31 PM, Peter Todd via bitcoin-dev < bitcoin-dev@lists.linuxfoundation.org> wrote: > > While I'm in favour of blocking covert usage of ASICBOOST, there's every > reason > to block non-covert usage of it as well. In a low margin business like > mining, > the advatange it gives is enormous - quite possibly 10x your profit margin > - > and given that barrier free access to being able to purchase ASICs is > already > an archilles heal for Bitcoin there is every reason to eliminate this legal > vulnerability. Additionally, it's a technical vulnerability as well: we > want > getting into the ASIC manufacturing and design business to have as low > barriers > to entry as is feasible, and the ASICBOOST exploit significantly increases > the > minimum capital requirements to do so. > Asicboost also has the problem that it isn't treating the hashing as a black box, and thus has impacts on what gets mined. In particular it creates an incentive to make blocks smaller. That's a very unwanted effect, and anything like it should be engineered out on principle. --001a114ac8f6d03947054c7669bc Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
On W= ed, Apr 5, 2017 at 7:31 PM, Peter Todd via bitcoin-dev &l= t;bitcoin-dev@lists.linuxfoundation.org> wrote:

While I'm in favour of blocking covert usage of ASICBOOST, there= 's every reason
to block non-covert usage of it as well. In a low margin business like mini= ng,
the advatange it gives is enormous - quite possibly 10x your profit margin = -
and given that barrier free access to being able to purchase ASICs is alrea= dy
an archilles heal for Bitcoin there is every reason to eliminate this legal=
vulnerability. Additionally, it's a technical vulnerability as well: we= want
getting into the ASIC manufacturing and design business to have as low barr= iers
to entry as is feasible, and the ASICBOOST exploit significantly increases = the
minimum capital requirements to do so.

= Asicboost also has the problem that it isn't treating the hashing as a = black box, and thus has impacts on what gets mined. In particular it create= s an incentive to make blocks smaller. That's a very unwanted effect, a= nd anything like it should be engineered out on principle.
--001a114ac8f6d03947054c7669bc--