[tor-dev] Guard node security: ways forward (An update from the dev meeting)

[Nicholas Hopper]

On Tue, Feb 25, 2014 at 5:04 PM, Nicholas Hopper <hopper at cs.umn.edu> wrote:
> Another thought: we also should investigate how various thresholds
> affect the relationship between the cumulative guard weight total and
> the total exit weight.

Well, that turns out not to be a real issue: even if we set the guard
threshold to 20MBps, the total guard weight still exceeds the total
exit weight.

Here is a chart showing what fraction of total guard bandwidth is
retained as we vary the guard threshold from 0 to 10MBps:

https://www-users.cs.umn.edu/~hopper/guards/guard_thresholds_bandwidth.png

And here's a chart showing what fraction of clients will choose the
highest (max%) and median (median%) guards as we vary the threshold
over the same range:

https://www-users.cs.umn.edu/~hopper/guards/guard_thresholds_weight.png

2MBps and 6MBps look like interesting points on the curves.

-- 
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Nicholas Hopper
Associate Professor, Computer Science & Engineering, University of Minnesota
Visiting Research Director, The Tor Project
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