[tor-bugs] #6401 [Analysis]: Update Tor network models from CSET paper

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#6401: Update Tor network models from CSET paper
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 Reporter:  robgjansen                              |          Owner:  robgjansen
     Type:  task                                    |         Status:  new       
 Priority:  normal                                  |      Milestone:            
Component:  Analysis                                |        Version:            
 Keywords:  simulation, performance, network model  |         Parent:            
   Points:                                          |   Actualpoints:            
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Comment(by robgjansen):

 __'''The first stab'''__

 The network model was updated to utilize EC2's m2_4xlarge instance (~68
 GiB), using Tor data (server descriptors, extra infos, etc) from the month
 of June 2012. Clients that more closely match TorPerf statistics were also
 added for cleaner comparison to the live network data. The resulting
 network is 2.5 times larger (both clients and relays) than we used in the
 CSET paper.

 '''The resulting network model:'''
 {{{
 * 250 high bandwidth http file servers

 * 1 high bandwidth torrent/swarm tracker authority

 * of the 250 relays:

   -100 exits-150 non-exits (1 authority)

 * of the 2500 clients (each download is from a random server):

   -50 im: upload 1 KiB, download 1 KiB, wait (0-5] seconds, repeat
   -2301 web: request and download 320 KiB, wait (0-60] seconds, repeat
   -100 bulk: request and download 5 MiB, repeat
   -9 p2p: from each other p2p client: download and upload 16 KiB, repeat
   -20 torperf 50 KiB: request and download 50 KiB, wait 60 seconds, repeat
   -20 torperf 1 MiB: request and download 1 MiB, wait 60 seconds, repeat
 }}}

 '''Load on the network''' was distributed as follows:
 {{{
 TYPE    #XFERS  GiB     %
 im      19046   0.018   0.052
 web     96170   29.349  84.135
 bulk    945     4.614   13.228
 p2p     21517   0.328   0.941
 perf50k 1024    0.049   0.140
 perf1m  537     0.524   1.503
 TOTAL   139239  34.883  100.000
 }}}

 '''Client performance''' is shown in
 [https://trac.torproject.org/projects/tor/attachment/ticket/6401/20120727-ec2
 -torperf-combined.pdf the attached graph here].

 Overall, it appears we are slightly overloaded compared to Tor's state in
 June. This is inferred from both graphs. Based on the graphs and the load
 breakdown, I'd like to cut out some web clients. I'd also like to see a
 higher percentage of the load coming from the P2P and bulk clients.

 So I'll run another experiment, this time on EC2, and post the results.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/6401#comment:5>
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