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Date: Mon, 30 Jan 2012 21:05:49 -0500
Message-ID: <CABsx9T0avsrL3134WaA3boG-cdx2NcgEH1mQG7Cef78ZV5UNkw@mail.gmail.com>
From: Gavin Andresen <gavinandresen@gmail.com>
To: Michael Hendricks <michael@ndrix.org>
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Cc: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitcoin-development] CAddrMan: Stochastic IP address manager
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> Cool design. =A0It seems resilient to many attacks. =A0A Sybil attack
> coming from a large botnet (which controls addresses in many ranges)
> can still fill all buckets in both tables, I think. =A0As far as I can
> tell, that wasn't possible with the old design.

Given the randomness in Pieter's design, that seems extremely unlikely
/ difficult to do. Is it possible to do a back-of-the-envelope
calculation to figure out what percentage of nodes on the network an
attacker would have to control to have a (say) 1% chance of a
successful Sybil attack?

I like this change; I'd like to pull it for the 0.6 release.

I've also been wondering if it is time to remove the IRC bootstrapping
mechanism; it would remove a fair bit of code and we'd stop getting
reports that various ISPs tag bitcoin as malware.  When testing the
list of built-in bootstrapping IP addresses I always connect fairly
quickly, and the DNS seeding hosts seems to be working nicely, too.

--=20
--
Gavin Andresen