Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1WTrFh-0000fq-HG for bitcoin-development@lists.sourceforge.net; Sat, 29 Mar 2014 11:16:41 +0000 X-ACL-Warn: Received: from qmta05.westchester.pa.mail.comcast.net ([76.96.62.48]) by sog-mx-1.v43.ch3.sourceforge.com with esmtp (Exim 4.76) id 1WTrFg-0003t1-G8 for bitcoin-development@lists.sourceforge.net; Sat, 29 Mar 2014 11:16:41 +0000 Received: from omta15.westchester.pa.mail.comcast.net ([76.96.62.87]) by qmta05.westchester.pa.mail.comcast.net with comcast id jPGG1n0051swQuc55PGbLp; Sat, 29 Mar 2014 11:16:35 +0000 Received: from crushinator.localnet ([IPv6:2601:6:4800:47f:219:d1ff:fe75:dc2f]) by omta15.westchester.pa.mail.comcast.net with comcast id jPGa1n00N4VnV2P3bPGb1m; Sat, 29 Mar 2014 11:16:35 +0000 From: Matt Whitlock To: Chris Beams Date: Sat, 29 Mar 2014 07:16:34 -0400 Message-ID: <1701792.nYQmSeReja@crushinator> User-Agent: KMail/4.12.3 (Linux/3.12.13-gentoo; KDE/4.12.3; x86_64; ; ) In-Reply-To: <83BBF97F-290E-4CF9-B062-92445ED35F27@beams.io> References: <1878927.J1e3zZmtIP@crushinator> <83BBF97F-290E-4CF9-B062-92445ED35F27@beams.io> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Spam-Score: 0.0 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [76.96.62.48 listed in list.dnswl.org] 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: 1WTrFg-0003t1-G8 Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] Presenting a BIP for Shamir's Secret Sharing of Bitcoin private keys 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: Sat, 29 Mar 2014 11:16:41 -0000 On Saturday, 29 March 2014, at 10:08 am, Chris Beams wrote: > Matt, could you expand on use cases for which you see Shamir's Secret Sharing Scheme as the best tool for the job? In particular, when do you see that it would be superior to simply going with multisig in the first place? Perhaps you see these as complimentary approaches, toward defense-in-depth? In any case, the Motivation and Rationale sections of the BIP in its current form are silent on these questions. I have added two new sections to address your questions. https://github.com/whitslack/btctool/blob/bip/bip-xxxx.mediawiki