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Date: Thu, 27 Nov 2014 02:22:35 +0000
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From: Gregory Maxwell <gmaxwell@gmail.com>
To: Isidor Zeuner <cryptocurrencies@quidecco.de>
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Cc: Bitcoin Development <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Deanonymisation of clients in Bitcoin P2P
 network paper
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> Since this attack vector has been discussed, I started making some
> measurements on how effective it is to connect to Bitcoin using Tor,
> and I found that the number of connections dropping to near-zero is
> a situation which occurs rather frequently, which suggests that there
> is still room to improve on the DoS handling.

I'm confused by this, I run quite a few nodes exclusively on tor and
chart their connectivity and have seen no such connection dropping
behaviour.

Can you tell me more about how you measured this?

[As an aside I agree that there are lots of things to improve here,
but the fact that users can in theory be forced off of tor via DOS
attacks is not immediately concerning to me because its a conscious
choice users would make to abandon their privacy (and the behaviour of
the system here is known and intentional). There are other mechanisms
available for people to relay their transactions than connecting
directly to the bitcoin network; so their choice isn't just abandon
privacy or don't use bitcoin at all.]