Hi there, I'd like to start a discussion on periodic rotation of outbound connections. E.g. every 2-10 minutes an outbound connections is dropped and replaced by a new one.
Motivation: Each bitcoin non-UPnP client behind NAT has 8 outbound connections which change only rarely (due to occasional remote side disconnections). A subset of these 8 entry nodes uniquely identifies a user. An attacker can listen for transactions in Bitcoin network and for each transaction record the first 8 peers which forwarded the transaction. If two distinct transactions (with unrelated bitcoin addresses) come from the same set of 8 peers, the attacker can conclude that they originated from the same user. This gives another method (in addition to transaction graph analysis) for an attacker to link different BC addresses of the same user. Also note that by default bitcoin clients advertise their public IP addresses. The attacker can link the advertised IP's to corresponding 8 entry nodes and use it to deanonymise Bitcoin clients. If a bitcoin client periodically rotates his set of outbound connections, his 8-peers fingerprint is blurred over time. Corresponding pull request is #4723. Some details are here: https://www.cryptolux.org/index.php/Bitcoin -- Ivan ------------------------------------------------------------------------------ _______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development