[tor-dev] Defending against guard discovery attacks by pinning middle nodes

[Michael Rogers]

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On 13/09/14 14:07, George Kadianakis wrote:
> a) To reduce the ownage probabilities we could pick a single
> middle node instead of 6. That will greatly improve guard
> discovery probabilities, and make us look like this:
> 
> HS -> guard -> middle -> <exit> -> RP (where <exit> is chosen from
> the set of all relays)
> 
> However, that will definitely degrade HS performance. I'm not sure 
> if Tor relays are able to handle all that concentrated HS traffic.
> Specifically, the guards/middles that get picked by popular HSes
> will get flooded with traffic that is never accounted for in Tor's
> load balancing equations (since HS traffic is not counted) and they
> will get hammered both by HS traffic and regular Tor traffic.

Hi George,

Could you explain what it means to say that HS traffic isn't counted
in the load balancing equations? Why is that so, and can it be changed
if that would allow a more secure HS design?

Cheers,
Michael
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