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Revise, Repeat

After looking at the measurements collected by the 'wxmstat' application, we realize that the signal strength on the nodes is too high. We want a more realistic environment, so we turn down the base station transmit power:

wget -qO- "http://wimaxrf:5052/wimaxrf/bs/set?bs_tx_power=15"
wget -qO- "http://wimaxrf:5052/wimaxrf/bs/restart"

He also uses the programmable attenuation on Sandbox 4 to create a situation where signal strength varies over the duration of the experiment. To do this, he adds some properties to the beginning of his experiment:

defProperty('attUrl', "http://internal2dmz.orbit-lab.org:5054/instr/set?", "Path to use to set attenuation")

and changes the sequence of events in the experiment to look like this:

onEvent(:ALL_UP_AND_INSTALLED) do |event|
  l =  [5,6,7,4,3,6,10,11,12,8,7,9,5,3,5,6,7,4,3,6,10,11,12,8,7,9,5,3]
  wait 5
  system("/home/#{ENV['USER']}/getbsconf -i wimaxrf --oml-server tcp:oml:3003 --oml-id console --oml-exp-id #{Experiment.ID}")
  group("server").exec("/usr/bin/python -m SimpleHTTPServer")
  group("client1").startApplications
  l.each do |a|
    system("/usr/bin/wget -qO- \"#{property.attUrl}portA=#{property.client1}\&portB=9\&att=#{a}\"")
    wait 5
  end
  group("client1").stopApplications
  wait 5
  group("client2").startApplications
  l.each do |a|
    system("/usr/bin/wget -qO- \"#{property.attUrl}portA=#{property.client2}\&portB=9\&att=#{a}\"")
    wait 5
  end
  group("client2").stopApplications
  wait 5
  allGroups.stopApplications
  Experiment.done
end

After running this modified experiment with

omf exec gec16-streamload2.rb

He looks at the iRODS plot and is happy with the result.

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