[tor-bugs] #31653 [Core Tor/Tor]: Padding cells sent with 0ms delay cause circuit failures

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#31653: Padding cells sent with 0ms delay cause circuit failures
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 Reporter:  pulls                                |          Owner:
                                                 |  mikeperry
     Type:  defect                               |         Status:
                                                 |  assigned
 Priority:  Medium                               |      Milestone:  Tor:
                                                 |  0.4.2.x-final
Component:  Core Tor/Tor                         |        Version:  Tor:
                                                 |  0.4.1.5
 Severity:  Normal                               |     Resolution:
 Keywords:  wtf-pad circpad-researchers-want     |  Actual Points:
  042-should                                     |
Parent ID:                                       |         Points:
 Reviewer:                                       |        Sponsor:
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Comment (by mikeperry):

 Bleh. It is unfortunate that clients need more accurate timers than
 relays.

 1. Do you have any sense as to if client-side timing is more important
 because most test crawls tend to use client-side timings as opposed to
 guard-side timings (and thus inherently get very high client-side timing
 resolution and visibility into Firefox delays), or because of something
 else that is just inherent to the HTTP protocol?

 2. If I were to write a patch that allowed either clients or relays to
 correctly fast-path this 0ms case to insert bursts of back-to-back packets
 without the circuit failure, would that help?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/31653#comment:16>
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