From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 84494C016E for ; Wed, 1 Jul 2020 00:54:01 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 6F81587278 for ; Wed, 1 Jul 2020 00:54:01 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id f7yPF8AXxPDk for ; Wed, 1 Jul 2020 00:54:00 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mail-40130.protonmail.ch (mail-40130.protonmail.ch [185.70.40.130]) by fraxinus.osuosl.org (Postfix) with ESMTPS id 0C38287257 for ; Wed, 1 Jul 2020 00:54:00 +0000 (UTC) Date: Wed, 01 Jul 2020 00:53:46 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail; t=1593564837; bh=Z+VHoDEqoQiQQycGj8dHzoPFwTxcaumwCtGig6rL2kM=; h=Date:To:From:Reply-To:Subject:In-Reply-To:References:From; b=stLAWKF5RXloH97M4n/hmrNT7cGLjeY3EcBWygWRDe/2hyqh/p0o4VQKPk1kP5s1X fffDxwqadSPK6jRgIIPoMuHdVwNjpL93aT+aeecNh+QBEHU/gPwg2+LYUy/vY/Sh0Y 1+Up57f7wiMXK7SjfKYAvbKCRUK35K8Y7w02ODZ4= To: Hilda , Bitcoin Protocol Discussion From: ZmnSCPxj Reply-To: ZmnSCPxj Message-ID: In-Reply-To: <24cf6c3f.207.173069b0747.Coremail.hildawithin@163.com> References: <24cf6c3f.207.173069b0747.Coremail.hildawithin@163.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [bitcoin-dev] Is Bitcoin mempool synchronized? X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Jul 2020 00:54:01 -0000 Good morning Hilda, > Hi there, > > I have been assuming Bitcoin system to be well synchronized, including me= mpools. But after being challenged, I started to think that I actually cann= ot verify this without knocking the door of every miner in every single sec= ond (just a time slice reasonable to me; stop torturing me by asking why). = Can anyone share any thoughts with me? No, definitely not. There is no good way to limit the amount of transactions someone can push a= t you, except by various heuristics. Yet those very same heuristics mean that someone with a good knowledge of t= hose heuristics can make your mempool desynchronized with that of somebody = else. Fortunately for Bitcoin, it is the blockchain itself that we synchronize on= . People cannot push blocks at you without doing the work of grinding towards= the difficulty target, thus it is not possible to spam blocks. TANSTAAGM - There Ain't No Such Thing As A Global Mempool For this reason, any consensus rule has to refer only to data inside blocks= , and never to data in mempools, are mempools are ephemeral and not synchro= nized across all nodes. Regards, ZmnSCPxj