[tor-bugs] #10968 [Tor]: Authorities should use past consensuses to assign relay flags

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#10968: Authorities should use past consensuses to assign relay flags
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     Reporter:  asn     |      Owner:
         Type:  task    |     Status:  new
     Priority:  normal  |  Milestone:  Tor: 0.2.???
    Component:  Tor     |    Version:
   Resolution:          |   Keywords:  tor-auth
Actual Points:          |  Parent ID:
       Points:          |
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Comment (by karsten):

 The following is not an attack, but an example why basing individual
 opinions on past group opinions is a bad idea.  Assume we have 9
 authorities in the network, and 5 of them vote for a set of relays being
 suitable guards whereas the other 4 vote against that.  The result is that
 the consensus says these relays should be guards.  At some point 2 of the
 first 5 authorities are removed from the network, so now it's 3 to 4, and
 the relays shouldn't be marked as possible guards anymore.  But with the
 suggested change, the remaining 7 authorities have to base their opinion
 on past consensuses, which means the relays in question will still be
 guards, at least for a while.  This seems wrong to me.

 Why not base an authority's opinion on its past opinions by parsing its
 own past votes?  If it was wrong all the time, the other authorities will
 overrule it anyway.  That's what the whole voting stuff is for, right?

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Ticket URL: <https://trac.torproject.org:443/projects/tor/ticket/10968#comment:9>
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