From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1RTERr-0008NH-Ro for bitcoin-development@lists.sourceforge.net; Wed, 23 Nov 2011 15:09:19 +0000 Received-SPF: pass (sog-mx-2.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.161.175 as permitted sender) client-ip=209.85.161.175; envelope-from=gavinandresen@gmail.com; helo=mail-gx0-f175.google.com; Received: from mail-gx0-f175.google.com ([209.85.161.175]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-MD5:128) (Exim 4.76) id 1RTERo-0006Rv-9C for bitcoin-development@lists.sourceforge.net; Wed, 23 Nov 2011 15:09:19 +0000 Received: by ggnh4 with SMTP id h4so1959041ggn.34 for ; Wed, 23 Nov 2011 07:09:10 -0800 (PST) MIME-Version: 1.0 Received: by 10.152.102.148 with SMTP id fo20mr14688509lab.51.1322060950294; Wed, 23 Nov 2011 07:09:10 -0800 (PST) Received: by 10.152.30.69 with HTTP; Wed, 23 Nov 2011 07:09:10 -0800 (PST) In-Reply-To: References: <201111231035.48690.andyparkins@gmail.com> <201111231313.12534.andyparkins@gmail.com> Date: Wed, 23 Nov 2011 10:09:10 -0500 Message-ID: From: Gavin Andresen To: Christian Decker Content-Type: text/plain; charset=ISO-8859-1 X-Spam-Score: -1.6 (-) 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 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (gavinandresen[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record -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: 1RTERo-0006Rv-9C Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] Addressing rapid changes in mining power 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, 23 Nov 2011 15:09:19 -0000 On Wed, Nov 23, 2011 at 9:38 AM, Christian Decker wrote: > At some point you might find an incredibly hard block that makes your forked > chain the hardest one in the network Seems to me that's the real problem with any "hardest block found in X minutes" scheme. If I get lucky and find a really extremely hard block then I have an incentive to keep it secret and build a couple more blocks on top of it, then announce them all at the same time. If the rest of the network rejects my longer chain because I didn't announce the extremely hard block in a timely fashion... then how could the network ever recover from a real network split? A network split/rejoin will look exactly the same. Bitcoin as-is doesn't have the "I got lucky and found an extremely hard block" problem because the difficulty TARGET is used to compute chain difficulty, not the actual hashes found. --- PS: I proposed a different method for dealing with large hash power drops for the testnet on the Forums yesterday, and am testing it today. -- -- Gavin Andresen