[tor-bugs] #5755 [Onionoo]: Atlas could show "fraction of Tor network by weight" graphs over time?

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#5755: Atlas could show "fraction of Tor network by weight" graphs over time?
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 Reporter:  arma         |          Owner:  karsten 
     Type:  enhancement  |         Status:  assigned
 Priority:  normal       |      Milestone:          
Component:  Onionoo      |        Version:          
 Keywords:               |         Parent:          
   Points:               |   Actualpoints:          
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Comment(by karsten):

 Here's a sample
 [https://trac.torproject.org/projects/tor/attachment/ticket/5755/path-
 selection-weights-2012-07-17.png graph] of nine relays in June 2012.  This
 graph contains five lines for every relay:

  - `advbw_frac` is the relative advertised bandwidth of a relay compared
 to the total advertised bandwidth in the network.  This is case 1 in the
 comment above.
  - `cw_frac` is the fraction of a relay's consensus weight compared to the
 sum of all consensus weights in the network.  This is case 2 above.
  - `P_guard` is the approximate probability of a relay to be selected for
 the guard position.  Consensus weights are weighted by Wgd and Wgg,
 whereas Wge and Wgm are both set to 0.  This is part of case 3 above.
  - `P_middle` is the approximate probability of a relay to be selected for
 the middle position.  Consensus weights are weighted by Wmd, Wmg, Wme, and
 Wmm.  This is part of case 3 above.
  - `P_exit` is the approximate probability of a relay to be selected for
 the exit position.  Consensus weights are weighted by Wed and Wee, whereas
 Weg and Wem are both set to 0.  This is part of case 3 above.

 So, the first two lines are easy to compute.  I'm less sure about the
 probabilities though.  I figured that path selection is a lot more complex
 than I thought.  For example, the subset of relays that are suitable for a
 given position in a given circuit varies from circuit to circuit which can
 cut the subset in half.  I tried to compute an "average" probability for
 selecting a given relay for a given position.  I'm not sure how close to
 reality these probabilities are.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/5755#comment:11>
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