Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 8EAD2978 for ; Mon, 13 Feb 2017 11:11:24 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from mail.bluematt.me (mail.bluematt.me [192.241.179.72]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id F2B01CD for ; Mon, 13 Feb 2017 11:11:23 +0000 (UTC) Received: from [26.83.158.48] (unknown [172.56.6.130]) by mail.bluematt.me (Postfix) with ESMTPSA id 11F5D135916; Mon, 13 Feb 2017 11:11:19 +0000 (UTC) Date: Mon, 13 Feb 2017 11:11:11 +0000 In-Reply-To: <9ca02a65-23df-5eb4-f9bd-7e05b54ec4ea@voskuil.org> References: <424C9E40-0B90-46A6-9C5E-30AE3E84E119@mattcorallo.com> <9ca02a65-23df-5eb4-f9bd-7e05b54ec4ea@voskuil.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable To: Eric Voskuil , Bitcoin Protocol Discussion , Pieter Wuille From: Matt Corallo Message-ID: <9ECDD902-1D2C-4500-8FC2-4DADF46E4318@mattcorallo.com> X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: libbitcoin@lists.dyne.org Subject: Re: [bitcoin-dev] BIP151 protocol incompatibility 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: Mon, 13 Feb 2017 11:11:24 -0000 I believe many, if not all, of those messages are sent irrespective of vers= ion number=2E In any case, I fail to see how adding any additional messages which are ig= nored by old peers amounts to a lack of backward compatibility=2E On February 13, 2017 11:54:23 AM GMT+01:00, Eric Voskuil wrote: >On 02/13/2017 02:16 AM, Matt Corallo wrote: >> For the reasons Pieter listed, an explicit part of our version >handshake and protocol negotiation is the exchange of otherwise-ignored >messages to set up optional features=2E > >Only if the peer is at the protocol level that allows the message: > >compact blocks: > >https://github=2Ecom/bitcoin/bitcoin/blob/master/src/protocol=2Eh#L217-L2= 42 > >fee filter: > >https://github=2Ecom/bitcoin/bitcoin/blob/master/src/protocol=2Eh#L211-L2= 16 > >send headers: > >https://github=2Ecom/bitcoin/bitcoin/blob/master/src/protocol=2Eh#L204-L2= 10 > >filters: > >https://github=2Ecom/bitcoin/bitcoin/blob/master/src/protocol=2Eh#L170-L1= 96 > >> Peers that do not support this ignore such messages, just as if they >had indicated they wouldn't support it, see, eg BIP 152's handshake=2E >Not >sure why you consider this backwards incompatible, as I would say it's >pretty clearly allowing old nodes to communicate just fine=2E > >No, it is not the same as BIP152=2E Control messages apart from BIP151 >are >not sent until *after* the version is negotiated=2E > >I assume that BIP151 is different in this manner because it has a >desire >to negotiate encryption before any other communications, including >version=2E > >e