From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-2.v43.ch3.sourceforge.com ([172.29.43.192] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1UT3M8-0003VT-0c for bitcoin-development@lists.sourceforge.net; Fri, 19 Apr 2013 04:55:28 +0000 X-ACL-Warn: Received: from mail-pd0-f173.google.com ([209.85.192.173]) by sog-mx-2.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1UT3M6-0002PK-Vi for bitcoin-development@lists.sourceforge.net; Fri, 19 Apr 2013 04:55:27 +0000 Received: by mail-pd0-f173.google.com with SMTP id v14so2007742pde.4 for ; Thu, 18 Apr 2013 21:55:21 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=mime-version:x-received:x-originating-ip:in-reply-to:references :date:message-id:subject:from:to:cc:content-type:x-gm-message-state; bh=pSY5pVc8ww/Qf8dvkiXc/3XbXLGrsTQVXIfkVreRT+o=; b=mIYt4awL+85m9u2Y6Bgp3nP8kBGiJ3870GaDULLnF7/jzzuwMvnRWKjyZUX+2QDllS dt55ps1U/CEycOLpJc8CC9ldVcfczPTk97JFk9hzw418nh3rA1/WlX4e7JXNys39MEr9 x3itS7MhLRed6mokeaRn5TqNeyDFilRFZDlliNplfzbLfd6cleUhcebMSaZ9FcVDRV6O WXI1VaDCgYV3jQiFVyjFHG13QeQtNk90WOroVcM4IGYmNegECraUo2o4if+nk61USEa8 e4i6zSuKfWtkgXVE2JH2L/GWaBPQhb8fJvbgswUz76gI8bbr+3KrMyTj2QcxDieeIUhj cvBw== MIME-Version: 1.0 X-Received: by 10.68.193.230 with SMTP id hr6mr17029285pbc.67.1366347320768; Thu, 18 Apr 2013 21:55:20 -0700 (PDT) Received: by 10.68.240.106 with HTTP; Thu, 18 Apr 2013 21:55:20 -0700 (PDT) X-Originating-IP: [99.43.178.25] In-Reply-To: References: <453bfc69-b2ab-4992-9807-55270fbda0db@email.android.com> <20130418081407.GC27888@savin> Date: Fri, 19 Apr 2013 00:55:20 -0400 Message-ID: From: Jeff Garzik To: John Dillon Content-Type: text/plain; charset=ISO-8859-1 X-Gm-Message-State: ALoCoQkInb6D4WdJ5OXvRcYKuSjpIuf7Se5xri6LLL1PQ+jvdppx8UCTSzJgAzCsX2W56v4KRAU/ X-Spam-Score: 0.0 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [209.85.192.173 listed in list.dnswl.org] X-Headers-End: 1UT3M6-0002PK-Vi Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] Anti DoS for tx replacement 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: Fri, 19 Apr 2013 04:55:28 -0000 On Fri, Apr 19, 2013 at 12:38 AM, John Dillon wrote: > I understand that Gavin has spent effort on security efforts against > small-scale attackers. It's the fact that he is so dismissive of the > threat that large attackers play that is what bothers me. But if I am > being divisive I understand. I cannot speak for Gavin, but speaking more generally, large attackers tend to belong in a thought-class all their own. Example 1: if some super-ASIC miner arises with 90% of hash power, and he starts behaving in a way contrary to the useful functioning of bitcoin, the community might decide to change the PoW algorithm at block height N. Example 2: If someone large DDoS's the entire P2P network, which is possible, manual intervention would be required to straighten out the mess. In each case, it's more about the community's mutual defense actions than any prepared defense. Speaking even more generally, bitcoin may be a billion-dollar invention, but that doesn't mean it has any funding for network defense! Unless cost structures and user attitudes change, development and deployment of major defense strategies seems unlikely. Which implies the community will simply wait for a [attack | explosion | crisis], and then hope we can unwind/repair the damage afterwards. -- Jeff Garzik exMULTI, Inc. jgarzik@exmulti.com