Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com
	designates 209.85.223.170 as permitted sender)
	client-ip=209.85.223.170; envelope-from=gmaxwell@gmail.com;
	helo=mail-ie0-f170.google.com; 
MIME-Version: 1.0
In-Reply-To: <544EFEE8.4000000@thinlink.com>
References: <544EA3D7.2050901@thinlink.com> <544EA85E.8010400@bluematt.me>
	<544EFEE8.4000000@thinlink.com>
Date: Tue, 28 Oct 2014 02:36:15 +0000
Message-ID: <CAAS2fgTW9uWewWbdRj6SCCAKU0D30jFiukDL9YPeG4n8LVwoYg@mail.gmail.com>
From: Gregory Maxwell <gmaxwell@gmail.com>
To: Tom Harding <tomh@thinlink.com>
Content-Type: text/plain; charset=UTF-8
Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] DS Deprecation Window
Precedence: list

On Tue, Oct 28, 2014 at 2:26 AM, Tom Harding <tomh@thinlink.com> wrote:
> Matt,
>
> You're right, thanks.  Without double-spend relay, miner won't know that
> some txes conflict with anything.

Even with that, the miner cannot tell, his only safe option is to
include no transactions at all.

Consider a malicious miner can concurrently flood all other miners
with orthogonal double spends (which he doesn't mine himself). These
other miners will all be spending some amount of their time mining on
these transactions before realizing others consider them
double-spends.