From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-1.v43.ch3.sourceforge.com ([172.29.43.191] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1W3aUh-0006mg-Nd for bitcoin-development@lists.sourceforge.net; Thu, 16 Jan 2014 00:07:35 +0000 Received-SPF: pass (sog-mx-1.v43.ch3.sourceforge.com: domain of mckay.com designates 37.1.88.131 as permitted sender) client-ip=37.1.88.131; envelope-from=robert@mckay.com; helo=mail.mckay.com; Received: from mail.mckay.com ([37.1.88.131]) by sog-mx-1.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1W3aUZ-0000Oe-Sa for bitcoin-development@lists.sourceforge.net; Thu, 16 Jan 2014 00:07:35 +0000 Received: from www-data by mail.mckay.com with local (Exim 4.76) (envelope-from ) id 1W3a1L-0000Qd-RK; Wed, 15 Jan 2014 23:37:15 +0000 To: Mike Hearn X-PHP-Originating-Script: 0:func.inc MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Wed, 15 Jan 2014 23:37:15 +0000 From: Robert McKay In-Reply-To: <5747D5DF-879B-4A60-8BD6-18251E7D5F47@plan99.net> References: <5747D5DF-879B-4A60-8BD6-18251E7D5F47@plan99.net> Message-ID: <60844494f46e330ec38f9275bc33f30b@webmail.mckay.com> X-Sender: robert@mckay.com User-Agent: Roundcube Webmail/0.5.3 X-Spam-Score: -1.9 (-) 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 SPF_PASS SPF: sender matches SPF record -0.3 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -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: 1W3aUZ-0000Oe-Sa Cc: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] Tor / SPV 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: Thu, 16 Jan 2014 00:07:35 -0000 On Wed, 15 Jan 2014 23:51:21 +0100, Mike Hearn wrote: > The goal of all that is that we get to keep our existing IPv4 based > anti-sybil heuristics, so we can’t possibly make anything worse, > only better. Plus, we’ve now set things up so in future if/when we > come up with a better anti-sybil system based on anonymous identities > or other fancy crypto, we can take out the “connect via clearnet” > step and go straight to using hidden services with only a very small > set of code changes and no new protocol work. I think it might be ok to use proof-of-stake on as an anti-sybil scheme on tor.. people would obviously not want to associate their wallet with their IP address, but is there any harm in associating it with a (temporary) tor service id (especially one that isn't used for anything other than relaying bitcoin transactions)? If each node you connect too can sign some challenge with a key that controls some BTC (and your client node verifies that the funds are different) then that might be useful.. even if it were only a small 0.01BTC stake that would be similar to the cost of obtaining another IP through a cheap VPS or VPN and significantly higher than the cost to an attacker who is able to MITM everything and operate on any IP anyway. Rob