From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1Wsq3l-0007xm-Dt for bitcoin-development@lists.sourceforge.net; Fri, 06 Jun 2014 09:03:37 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of gmail.com designates 209.85.217.174 as permitted sender) client-ip=209.85.217.174; envelope-from=gmaxwell@gmail.com; helo=mail-lb0-f174.google.com; Received: from mail-lb0-f174.google.com ([209.85.217.174]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1Wsq3k-0006UY-GR for bitcoin-development@lists.sourceforge.net; Fri, 06 Jun 2014 09:03:37 +0000 Received: by mail-lb0-f174.google.com with SMTP id n15so1333523lbi.33 for ; Fri, 06 Jun 2014 02:03:29 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.152.20.168 with SMTP id o8mr623965lae.78.1402045409832; Fri, 06 Jun 2014 02:03:29 -0700 (PDT) Received: by 10.112.235.72 with HTTP; Fri, 6 Jun 2014 02:03:29 -0700 (PDT) In-Reply-To: <20140606084852.GA30247@netbook.cypherspace.org> References: <20140606081933.GA29458@savin> <20140606084852.GA30247@netbook.cypherspace.org> Date: Fri, 6 Jun 2014 02:03:29 -0700 Message-ID: From: Gregory Maxwell To: Adam Back 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: 1Wsq3k-0006UY-GR Cc: Bitcoin Development Subject: Re: [Bitcoin-development] NODE_BLOOM service bit 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, 06 Jun 2014 09:03:37 -0000 On Fri, Jun 6, 2014 at 1:48 AM, Adam Back wrote: > Advertising NODE BLOOM as a service sounds good. > > But the critique of bloom filters, I am not so sure prefix filters are > better. Prefix filters offer questionable privacy tradeoffs in my opinion. > Same problem as with stealth address proposed use of prefixes. > > All for scalability, efficiency and decentralization but not ideally at the > expense of nuking privacy. The effects on privacy are cumulative, and > affect everyone not just the user. Same pattern of local decision, global > effect as with reused addresses. The performance Bytecoin/Monero/Fantom/etc. systems that use ECDH addresses for all transactions seem to be suggesting that the prefixes aren't really needed. At least with current system rules doing the ECDH for each transaction seems pretty reasonable.