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 EB03989C for ; Wed, 5 Jul 2017 03:51:50 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from zinan.dashjr.org (zinan.dashjr.org [192.3.11.21]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 470A7125 for ; Wed, 5 Jul 2017 03:51:50 +0000 (UTC) Received: from ishibashi.localnet (unknown [IPv6:2001:470:5:265:a45d:823b:2d27:961c]) (Authenticated sender: luke-jr) by zinan.dashjr.org (Postfix) with ESMTPSA id AC62C38A2257; Wed, 5 Jul 2017 03:50:56 +0000 (UTC) X-Hashcash: 1:25:170705:bitcoin-dev@lists.linuxfoundation.org::hGHGS9IjzKUId7sI:aJ/W5 X-Hashcash: 1:25:170705:shaolinfry@protonmail.ch::SnsrZhP+fW8dfMLp:cvHSQ From: Luke Dashjr To: bitcoin-dev@lists.linuxfoundation.org, shaolinfry Date: Wed, 5 Jul 2017 03:50:51 +0000 User-Agent: KMail/1.13.7 (Linux/4.9.16-gentoo; KDE/4.14.32; x86_64; ; ) References: In-Reply-To: X-PGP-Key-Fingerprint: E463 A93F 5F31 17EE DE6C 7316 BD02 9424 21F4 889F X-PGP-Key-ID: BD02942421F4889F X-PGP-Keyserver: hkp://pgp.mit.edu MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Message-Id: <201707050350.53122.luke@dashjr.org> X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Subject: Re: [bitcoin-dev] Height based vs block time based thresholds 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: Wed, 05 Jul 2017 03:51:51 -0000 I've already opened a PR almost 2 weeks ago to do this and fix the other issues BIP 9 has. https://github.com/bitcoin/bips/pull/550 It just needs your ACK to merge. On Wednesday 05 July 2017 1:30:26 AM shaolinfry via bitcoin-dev wrote: > Some people have criticized BIP9's blocktime based thresholds arguing they > are confusing (the first retarget after threshold). It is also vulnerable > to miners fiddling with timestamps in a way that could prevent or delay > activation - for example by only advancing the block timestamp by 1 second > you would never meet the threshold (although this would come a the penalty > of hiking the difficulty dramatically). On the other hand, the exact date > of a height based thresholds is hard to predict a long time in advance due > to difficulty fluctuations. However, there is certainty at a given block > height and it's easy to monitor. If there is sufficient interest, I would > be happy to amend BIP8 to be height based. I originally omitted height > based thresholds in the interests of simplicity of review - but now that > the proposal has been widely reviewed it would be a trivial amendment.