Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 77BC3DAF for ; Thu, 4 Feb 2016 19:36:59 +0000 (UTC) X-Greylist: whitelisted by SQLgrey-1.7.6 Received: from mail-io0-f182.google.com (mail-io0-f182.google.com [209.85.223.182]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id F309C16B for ; Thu, 4 Feb 2016 19:36:58 +0000 (UTC) Received: by mail-io0-f182.google.com with SMTP id d63so104746684ioj.2 for ; Thu, 04 Feb 2016 11:36:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; bh=xW0se4ZwEMTWvY6CUVmulvnKkYrbf2wzUUsqYWsZmDQ=; b=EYXK0lEcjOl2RqjWsroQcM992yxVwKqdp+RnCxSBdltlunS7zzcsCu6pdsUMpT4hgs Q73Ry8P2bgvxEIB7t7k4ezucfXxA1tLlpvZD8BlizKgz4LpKQZvBvktusPBzxXUc/93p bb8Dinf+CUmq13Kf9rlFdGQN+DGA0Wh8FkKVt8RBOBqqUHt8Dt9ld8cAmb77MMpg7ym2 nu8Get204fpwkc7TqPUsXzrFpi8mEuIeYz+TlFuZS7oI54HJUD92sbZnPr/VwHtX0ARn gtu41LZlhz9aIoSjRB8KIMtqpZO7Oeri+t3tbbzMvEjyU1Z1lnRA5Rhg78mU2dd3vC/e jemw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:sender:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=xW0se4ZwEMTWvY6CUVmulvnKkYrbf2wzUUsqYWsZmDQ=; b=HnDObpwoU6BWUPf8nupdKMJEqa/Hzt2kKIeNk7VvbjR0vIWhsyyge6/p7IvlBW4Vjq /GFAitpWgBJrSl8HtAG/dTtJkNF+TAse99Qh+NYhDGiXrYi41QOV2DBYWsYyELVr44LS PyWRQmWWcRrTtdvC9ygSKuOju2xWHoVsin3vpBzolGF9CEyEsmk2VOGR7J+GJL52vvbU CCtIEaCj32lXhPTtSr8wSEitqlYAFbIglQWJ53MU7oWu87dS7jad/VNZCNlnfERtipz/ fwE+sAFKtoaEDbElKeRXqSMJnJgnAsrh2LkLzSr/8KbCiy0OVbW97wneSGM40vnQpkvv PVJQ== X-Gm-Message-State: AG10YOQ+qoYvVn8RfvCKRPHbbUJZ03E34PsSWqXnOurcFrtHrVWJkLYKO9KY+5dXNzBrhbzerOdn5cAJwbifSA== MIME-Version: 1.0 X-Received: by 10.107.4.213 with SMTP id 204mr10650402ioe.134.1454614618464; Thu, 04 Feb 2016 11:36:58 -0800 (PST) Sender: gmaxwell@gmail.com Received: by 10.107.132.75 with HTTP; Thu, 4 Feb 2016 11:36:58 -0800 (PST) In-Reply-To: References: Date: Thu, 4 Feb 2016 19:36:58 +0000 X-Google-Sender-Auth: SKJQ_1muXoPuxO4b3BEvWCMYEFQ Message-ID: From: Gregory Maxwell To: jl2012 Content-Type: text/plain; charset=UTF-8 X-Spam-Status: No, score=-2.6 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: Bitcoin Dev Subject: Re: [bitcoin-dev] Hardfork bit BIP X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Development Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 Feb 2016 19:36:59 -0000 On Thu, Feb 4, 2016 at 5:14 PM, jl2012 via bitcoin-dev wrote: > https://github.com/bitcoin/bips/pull/317 I think this is a good idea, and I've independently proposed it in the past. I agree with most of luke's language nitpicks. It could, however, be pointed out that the version number flag is not sufficient in the deployed network, because many clients also do not validate the version field, due to a disinterest in security great enough to not implement anything around height-in-coinbase. So to fully achieve the intended effect using the highest bit of prev would currently be much more effective.