Randomize link quality

awful-network.md

Creating an awful Wi-Fi network

1. Plug an Ethernet cable into your computer. You'll need this for Internet connectivity while your Wi-Fi card is used to create a network.

2. Enable Internet Sharing in System Preferences.

3. Get your phone connected to the network you just created and make sure you can browse the web.

4. Ensure dummynet'd packets are still routed through the normal rules so masquerading works:

    eleos@Nebula ~$ sudo sysctl -w net.inet.ip.fw.one_pass=0
    net.inet.ip.fw.one_pass: 0 -> 0
   

5. Configure the low-quality pipe:

    eleos@Nebula ~$ sudo ipfw pipe 1 config bw 14KB/s
    eleos@Nebula ~$ sudo ipfw pipe 1 config plr 0.01
   

6. Route packets into the pipe, but only for traffic over your AirPort interface:

    eleos@Nebula ~$ sudo ipfw add 10 pipe 1 ip from any to any via en1
    00010 pipe 1 ip from any to any via en1
   

network.rb

srand(5)

while true do
  plr = (rand * 100).round / 100.0
  if plr > 0.8
    plr = 1.0
  end
  bw = rand(20)
  plr_command = "sudo ipfw pipe 1 config plr #{plr}"
  bw_command = "sudo ipfw pipe 1 config bw #{bw}KB/s"
  puts plr_command
  `#{plr_command}`
  puts bw_command
  `#{bw_command}`
  length = rand(45)
  puts "sleep #{length}"
  sleep length
end