Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 59B3B151B for ; Wed, 24 Oct 2018 18:21:09 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail2.protonmail.ch (mail2.protonmail.ch [185.70.40.22]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id 5D1627CB for ; Wed, 24 Oct 2018 18:21:08 +0000 (UTC) Date: Wed, 24 Oct 2018 18:21:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=default; t=1540405261; bh=xBc4Qb1p5Ie8CUFqgrMSLWneKoOFgDWq4nGXsSa5ASM=; h=Date:To:From:Cc:Reply-To:Subject:In-Reply-To:References: Feedback-ID:From; b=Ycj8hGOFrTDdpnbbIWoM7zfB4Ve0Imd9M12cD+TjiO8wYdklS/B4WYXzNQQG9EOnX vXRNp9MusOPlNGttKbSn4mJKmg2K0/Kl5KOKn9+oz9hyqnjOG5rc4BCTMywm+FKPMI +E3CnwlAh6GJ1YiM8Ay5l9rwSrCKhZziaJhxUlcA= To: Gregory Maxwell , Bitcoin Protocol Discussion From: rhavar@protonmail.com Reply-To: rhavar@protonmail.com Message-ID: In-Reply-To: References: <62ab0a37-2969-d9fe-5849-9362154560d0@riseup.net> Feedback-ID: RdfuD--Ffc-FNb_4UIG1XA3s5stj1f6Yt84KENdha_3WoiW3STYpu7X5uGR72LvTfQZpxEhSRHGSlNfV5XM5RA==:Ext:ProtonMail MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-2.7 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, 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 X-Mailman-Approved-At: Wed, 24 Oct 2018 19:19:09 +0000 Subject: Re: [bitcoin-dev] Transaction Input/Output Sorting 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, 24 Oct 2018 18:21:09 -0000 Actually, I think it can be calculated a bit smarter using maths (which unf= ortunately I'm not very good at...). But I assume it's something like: ``` falsePositiveChances :=3D 0.0 foreach( transaction of transactions) { =09falsePositiveChances +=3D (1 / factorial(transaction.Inputs)) * (1 / fac= torial(transaction.Ouputs)) } totalFalsePositives :=3D falsePositiveChances / transactions.length ``` If so, I get 42.4% false positive rate. So clearly bip69 is getting used a = fair bit, but not nearly as much as randomization. -Ryan =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90 Original Me= ssage =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90 On Wednesday, October 24, 2018 10:52 AM, wrote: > That's pretty easy to quantify. I wrote a quick script to grab the last f= ew blocks, and then shuffle the inputs/outputs before testing if each trans= action is bip69 or not. > > The result was 42% of all transactions would accidentally be bip69 when r= andomized. > > So clearly randomization is a lot more popular than bip69 at the moment, = but I'm not sure that it matters much. As soon as you have more than a few = inputs/outputs, you can tell with a high confidence if the transaction is b= ip69 or not. > > And of course if you're clustering a wallet, you can figure out extremely= easily how that wallet behaves wrt bip6. > > -Ryan > > =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90 Original = Message =E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90=E2=80=90 > On Wednesday, October 24, 2018 9:12 AM, Gregory Maxwell via bitcoin-dev b= itcoin-dev@lists.linuxfoundation.org wrote: > > > On Wed, Oct 24, 2018 at 3:52 PM Chris Belcher via bitcoin-dev > > bitcoin-dev@lists.linuxfoundation.org wrote: > > > > > Thanks for bringing our attention to this important topic. > > > According to (https://p2sh.info/dashboard/db/bip-69-stats) around 60%= of > > > transaction follow bip69 (possibly just by chance). > > > > A two input randomly ordered transaction has a 50% chance of > > 'following' bip-69. So 60% sound like a small minority.