Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-2.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1YsGO2-0000a2-Cb for bitcoin-development@lists.sourceforge.net; Tue, 12 May 2015 20:02:42 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.213.173 as permitted sender) client-ip=209.85.213.173; envelope-from=gmaxwell@gmail.com; helo=mail-ig0-f173.google.com; Received: from mail-ig0-f173.google.com ([209.85.213.173]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1YsGO1-0000lb-EN for bitcoin-development@lists.sourceforge.net; Tue, 12 May 2015 20:02:42 +0000 Received: by igbyr2 with SMTP id yr2so119195993igb.0 for ; Tue, 12 May 2015 13:02:36 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.50.114.9 with SMTP id jc9mr1937327igb.49.1431460956178; Tue, 12 May 2015 13:02:36 -0700 (PDT) Received: by 10.107.15.82 with HTTP; Tue, 12 May 2015 13:02:36 -0700 (PDT) In-Reply-To: References: <20150512171640.GA32606@savin.petertodd.org> Date: Tue, 12 May 2015 20:02:36 +0000 Message-ID: From: Gregory Maxwell To: Jeff Garzik Content-Type: text/plain; charset=UTF-8 X-Spam-Score: -1.6 (-) 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 (gmaxwell[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain 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: 1YsGO1-0000lb-EN Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Proposed additional options for pruned nodes 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: Tue, 12 May 2015 20:02:42 -0000 On Tue, May 12, 2015 at 7:38 PM, Jeff Garzik wrote: > One general problem is that security is weakened when an attacker can DoS a > small part of the chain by DoS'ing a small number of nodes - yet the impact > is a network-wide DoS because nobody can complete a sync. It might be more interesting to think of that attack as a bandwidth exhaustion DOS attack on the archive nodes... if you can't get a copy without them, thats where you'll go. So the question arises: does the option make some nodes that would have been archive not be? Probably some-- but would it do so much that it would offset the gain of additional copies of the data when those attacks are not going no. I suspect not. It's also useful to give people incremental ways to participate even when they can't swollow the whole pill; or choose to provide the resource thats cheap for them to provide. In particular, if there is only two kinds of full nodes-- archive and pruned; then the archive nodes take both a huge disk and bandwidth cost; where as if there are fractional then archives take low(er) bandwidth unless the fractionals get DOS attacked.