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Cc: Ivan Pustogarov <ivan.pustogarov@uni.lu>,
Bitcoin Development <bitcoin-development@lists.sourceforge.net>
Subject: Re: [Bitcoin-development] Outbound connections rotation
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--089e013a05dec9515a0500eaae63
Content-Type: text/plain; charset=UTF-8
>
> Connection rotation would be fine for improving a node's knoweldge
> about available peers and making the network stronger against
> partitioning.
>
It's also the first/next step towards decentralising the DNS seeds (for SPV
clients), as it'd allow each node to explore the network and return better
quality results in getaddr.
> If you rotate where you send out your transactions then with
> very high probability a sybil pretending to be many nodes will observe
> you transmitting directly.
>
This is sort of what Tor is going through with their guard nodes and how
often to rotate them.
I think the attack Ivan is talking about does not require sybil attacks to
work though, just listening to lots of peers. Raising the bar to require
the attacker to receive lots of connections seems like a win.
--089e013a05dec9515a0500eaae63
Content-Type: text/html; charset=UTF-8
Content-Transfer-Encoding: quoted-printable
<div dir=3D"ltr"><div class=3D"gmail_extra"><div class=3D"gmail_quote"><blo=
ckquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #c=
cc solid;padding-left:1ex">Connection rotation would be fine for improving =
a node's knoweldge<br>
about available peers and making the network stronger against<br>
partitioning.<br></blockquote><div><br></div><div>It's also the first/n=
ext step towards decentralising the DNS seeds (for SPV clients), as it'=
d allow each node to explore the network and return better quality results =
in getaddr.</div>
<div>=C2=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8=
ex;border-left:1px #ccc solid;padding-left:1ex">If you rotate where you sen=
d out your transactions then with<br>
very high probability a sybil pretending to be many nodes will observe<br>
you transmitting directly.<br></blockquote><div><br></div><div>This is sort=
of what Tor is going through with their guard nodes and how often to rotat=
e them.</div><div><br></div><div>I think the attack Ivan is talking about d=
oes not require sybil attacks to work though, just listening to lots of pee=
rs. Raising the bar to require the attacker to receive lots of connections =
seems like a win.</div>
</div></div></div>
--089e013a05dec9515a0500eaae63--
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