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 1WtMXL-0007FF-HH for bitcoin-development@lists.sourceforge.net; Sat, 07 Jun 2014 19:44:19 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.192.51 as permitted sender) client-ip=209.85.192.51; envelope-from=etotheipi@gmail.com; helo=mail-qg0-f51.google.com; Received: from mail-qg0-f51.google.com ([209.85.192.51]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1WtMXK-00047t-Os for bitcoin-development@lists.sourceforge.net; Sat, 07 Jun 2014 19:44:19 +0000 Received: by mail-qg0-f51.google.com with SMTP id q107so6994765qgd.38 for ; Sat, 07 Jun 2014 12:44:13 -0700 (PDT) X-Received: by 10.140.98.116 with SMTP id n107mr18881158qge.93.1402170253292; Sat, 07 Jun 2014 12:44:13 -0700 (PDT) Received: from [192.168.42.77] ([172.56.29.207]) by mx.google.com with ESMTPSA id 19sm8313186qgx.48.2014.06.07.12.44.11 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Sat, 07 Jun 2014 12:44:12 -0700 (PDT) Message-ID: <53936B87.3060804@gmail.com> Date: Sat, 07 Jun 2014 15:44:07 -0400 From: Alan Reiner User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0 MIME-Version: 1.0 To: bitcoin-development@lists.sourceforge.net References: <20140606081933.GA29458@savin> <20140606084852.GA30247@netbook.cypherspace.org> <20140606090441.GA19256@savin> <20140606104543.GA31085@netbook.cypherspace.org> <20140606164639.GB14891@savin> <20140606170524.GA29195@savin> <20140606174545.GB29195@savin> In-Reply-To: X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Spam-Score: -1.6 (-) 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 [209.85.192.51 listed in list.dnswl.org] -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 (etotheipi[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: 1WtMXK-00047t-Os Subject: Re: [Bitcoin-development] Bloom bait 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: Sat, 07 Jun 2014 19:44:19 -0000 On 06/07/2014 07:22 AM, Mike Hearn wrote: > > You can send different bloom filters to different peers too, so I'm > not sure why you're listing subsetting as a unique advantage of prefix > filters. > > Please let me know if we've gone down this path before, but it would seem that the more different bloom filters you create, the more information you give away. It would be most useful to create a single bloom filter that captures every address you ever intend to use (say a look ahead of 1000 addresses), and then only ever communicate that. Once people see multiple filters that you produce, they can start looking at the intersection of them to reduce the identity space. I would expect that after enough bloom variants, they could figure out a perfect subset of blockchain addresses in your wallet. (I suppose you could intentionally select an extra 20% addresses to include in every bloom filter, but it's a hack). Similarly, if you keep updating your bloom filter to include more addresses, the difference in what passes through the previous one and the new one gives away information about new addresses you created.