From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1YDJ7V-0004vF-Dr for bitcoin-development@lists.sourceforge.net; Mon, 19 Jan 2015 20:40:21 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of gmail.com designates 74.125.82.53 as permitted sender) client-ip=74.125.82.53; envelope-from=mh.in.england@gmail.com; helo=mail-wg0-f53.google.com; Received: from mail-wg0-f53.google.com ([74.125.82.53]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1YDJ7T-0003fK-RK for bitcoin-development@lists.sourceforge.net; Mon, 19 Jan 2015 20:40:21 +0000 Received: by mail-wg0-f53.google.com with SMTP id x13so33533402wgg.12 for ; Mon, 19 Jan 2015 12:40:13 -0800 (PST) MIME-Version: 1.0 X-Received: by 10.180.107.164 with SMTP id hd4mr11374005wib.7.1421700013440; Mon, 19 Jan 2015 12:40:13 -0800 (PST) Sender: mh.in.england@gmail.com Received: by 10.194.188.9 with HTTP; Mon, 19 Jan 2015 12:40:13 -0800 (PST) In-Reply-To: <54BD6314.60607@gmail.com> References: <2C7D6208-1921-4DDC-90FE-DB1ABE1D61DB@petertodd.org> <54BD6314.60607@gmail.com> Date: Mon, 19 Jan 2015 21:40:13 +0100 X-Google-Sender-Auth: ZeIzx4iWyaug9fojXNF5l9x58Ho Message-ID: From: Mike Hearn To: Alan Reiner Content-Type: multipart/alternative; boundary=e89a8f3ba0854745fb050d075487 X-Spam-Score: -0.5 (/) 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 (mh.in.england[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 1.0 HTML_MESSAGE BODY: HTML included in message 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: 1YDJ7T-0003fK-RK Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] BIP70: why Google Protocol Buffers for encoding? 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: Mon, 19 Jan 2015 20:40:21 -0000 --e89a8f3ba0854745fb050d075487 Content-Type: text/plain; charset=UTF-8 > > I'm a bit confused. It's been a long time since I looked at protobuf (and > will have to dig into it soon), but I seem to recall it doesn't have any of > the determinism properties you guys just said. > It's not guaranteed no, which is why we store signed sub-messages as byte arrays instead of typed submessages. In practice though, most implementations do seem to serialise things the same way. I recall Python used to be an odd one out, unsure if it still is. OK, I guess we can boil this down more simply. BIP 70 uses protocol buffers because I designed it and implemented the original prototype (with lots of input from Gavin and an earlier proposal by sipa). I used protocol buffers because, beyond all their nice properties, I used to work at Google and so was very familiar with them. --e89a8f3ba0854745fb050d075487 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I'= m a bit confused.=C2=A0 It's been a long time since I looked at protobuf (and will have to dig into it soon), but I seem to recall it doesn't have any of the determinism properties you guys just said.=C2=A0

It's not guarante= ed no, which is why we store signed sub-messages as byte arrays instead of = typed submessages. In practice though, most implementations do seem to seri= alise things the same way. I recall Python used to be an odd one out, unsur= e if it still is.

OK, I guess we can boil this dow= n more simply. BIP 70 uses protocol buffers because I designed it and imple= mented the original prototype (with lots of input from Gavin and an earlier= proposal by sipa). I used protocol buffers because, beyond all their nice = properties, I used to work at Google and so was very familiar with them.

--e89a8f3ba0854745fb050d075487--