[tor-bugs] #10969 [Core Tor/Tor]: Set of guard nodes can act as a linkability fingerprint

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#10969: Set of guard nodes can act as a linkability fingerprint
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 Reporter:  asn                                  |          Owner:  (none)
     Type:  defect                               |         Status:
                                                 |  assigned
 Priority:  High                                 |      Milestone:  Tor:
                                                 |  unspecified
Component:  Core Tor/Tor                         |        Version:
 Severity:  Normal                               |     Resolution:
 Keywords:  tor-client, tor-guard, XKEYSCORE,    |  Actual Points:
  prop259, SponsorU-deferred, QUICKANT           |
Parent ID:                                       |         Points:  large
 Reviewer:                                       |        Sponsor:
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Comment (by cypherpunks):

 Replying to [ticket:10969 asn]:
 >Still, as an example, in a city with only 500 Tor users, even if each
 person has a single guard, there are only going to be a few people with
 the same guard node (and some of them might always be in the same physical
 location, so the one who roams is probably the same person).

 when i think about it, i wonder if it also makes it worse when the same
 user uses different devices clients that all use their own guard. this
 should increase likability as well as roaming in the same location but it
 is likely different guard from the same nat in fine granular traffic
 pattern

 should the single user better use same guard across everything?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10969#comment:51>
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