[tor-bugs] #31788 [Core Tor/Tor]: Circuit padding trace simulator

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#31788: Circuit padding trace simulator
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 Reporter:  mikeperry                          |          Owner:  (none)
     Type:  enhancement                        |         Status:  new
 Priority:  Medium                             |      Milestone:
Component:  Core Tor/Tor                       |        Version:
 Severity:  Normal                             |     Resolution:
 Keywords:  circpad-researchers-want, wtf-pad  |  Actual Points:
Parent ID:                                     |         Points:
 Reviewer:                                     |        Sponsor:
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Comment (by pulls):

 Thank you for the detailed instructions Mike, very useful. I've started
 working on implementing a simulator, goal is to have something useful by
 the end of the month. Also thank you Nick for merging doc/HACKING/design,
 it helped me a lot.

 The implementation now requires a client and relay trace (got a lazy
 python script to simulate a relay trace from a client trace as well). My
 biggest gripe right now is time. Every time a client/relay machine
 triggers padding, a corresponding event has to be added to the
 relay/client trace with an estimated time. This estimate will always be,
 well, wrong. I'm not sure it's possible to make this estimate in such a
 way that it'll fool time-based classifiers, even if we add in guard traces
 for better estimates and patches as you mention Mike.

 Right now I think it might be best as a starting point to just try to use
 the simulator to find optimal machines against attacks like Deep
 Fingerprinting that ignores time. Once we have a better understanding of
 how feasible and costly that is we can look more closely at how time
 changes things.

 Any thoughts on this? Have I missed some other reason than time estimates
 for including guard traces?

 Also, if some other researcher working on this wants to collaborate please
 reach out.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/31788#comment:3>
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