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Simulating a Slow Internet Connection

ankursethi.in

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Re: Simulating a Slow Internet Connection

#3

Post by Terretta »

If you're on a Mac, try the Network Link Conditioner from the Hardware IO tools downloads in Apple Dev portal.

http://www.neglectedpotential.com/2012/05/slow-your-apps-rol...

PS. The sleep trick is helpful, but in addition to latency, you ideally want to experience packet loss and other weirdness.

Re: Simulating a Slow Internet Connection

#6

Post by tincholio »

Terretta wrote: post #3

If you're on a Mac, try the Network Link Conditioner from the Hardware IO tools downloads in Apple Dev portal. http://www.neglectedpotential.com/2012/05/slow-your-apps-rol... PS. The sleep trick is helpful, but in addition to latency, you ideally want to experience packet loss and other weirdness.

For TCP connections packet loss will translate into latency... His method of simulation is not good, though. On linux, he could (probably) emulate this properly with NetEm and some virtual interfaces, by limiting rates and introducing actual "propagation delays"

Re: Simulating a Slow Internet Connection

#7

Post by ddb »

Terretta wrote: post #3

If you're on a Mac, try the Network Link Conditioner from the Hardware IO tools downloads in Apple Dev portal. http://www.neglectedpotential.com/2012/05/slow-your-apps-rol... PS. The sleep trick is helpful, but in addition to latency, you ideally want to experience packet loss and other weirdness.

This can be done with native osx tools as well. Here's a snippet I created once:

  # First add a rule for all local traffic to port 80 to go into pipe 1
  # 100 is the rule number which will be used for referencing the rule later
  sudo ipfw add 100 pipe 1 ip from 127.0.0.1 to 127.0.0.1 dst-port http
  
  # To display the rule use
  # sudo ipfw show 100
  
  # configure the settings of the pipe as you please
  # 50kbit/s bandwidth
  sudo ipfw pipe 1 config bw 50Kbit
  # 200ms lag
  sudo ipfw pipe 1 config delay 200ms
  # 20% random packet loss
  sudo ipfw pipe 1 config plr 0.2
  
  # To display the current connections on the pipe use:
  # sudo ipfw pipe 1 show
  
  # when finished testing don't forget to delete rule and pipe
  sudo ipfw delete 100
  sudo ipfw pipe 1 delete

Re: Simulating a Slow Internet Connection

#8

Post by cortesoft »

Terretta wrote: post #3

If you're on a Mac, try the Network Link Conditioner from the Hardware IO tools downloads in Apple Dev portal. http://www.neglectedpotential.com/2012/05/slow-your-apps-rol... PS. The sleep trick is helpful, but in addition to latency, you ideally want to experience packet loss and other weirdness.

The one I have always used on Mac is SpeedLimit: http://mschrag.github.io/

Re: Simulating a Slow Internet Connection

#10

Post by gingerlime »

ddb wrote: post #7
Terretta wrote: post #3

If you're on a Mac, try the Network Link Conditioner from the Hardware IO tools downloads in Apple Dev portal. http://www.neglectedpotential.com/2012/05/slow-your-apps-rol... PS. The sleep trick is helpful, but in addition to latency, you ideally want to experience packet loss and other weirdness.

This can be done with native osx tools as well. Here's a snippet I created once: # First add a rule for all local traffic to port 80 to go into pipe 1 # 100 is the rule number which will be used for referencing the rule later sudo ipfw add 100 pipe 1 ip from 127.0.0.1 to 127.0.0.1 dst-port http # To display the rule use # sudo ipfw show 100 # configure the settings of the pipe as you please # 50kbit/s bandwidth sudo…

This looks great, do you know if there's an equivalent for linux? can you do something like this with iptables / ufw?
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