fiddler

Simulate network speeds using Fiddler


I am using Fiddler and want to simulate different network speeds

Is there any published data that I can use to simulate different speeds using the delay value ?

Following is default code of Fiddler to simulate 56kb modem speed.

if (m_SimulateModem) {
    // Delay sends by 300ms per KB uploaded.
    oSession["request-trickle-delay"] = "300"; 
    // Delay receives by 150ms per KB downloaded.
    oSession["response-trickle-delay"] = "150"; 
}

I want the delay values for 256kbps, 512kbps, 1Mbps etc...


Solution

  • This is simply a math problem.

    Assuming that content is available instantly (e.g. you're playing it back from the AutoResponder) then the only delay is controlled by request-trickle-delay and response-trickle-delay flags.

    There are 1000 milliseconds per second.

    So, if you want to gate the connection to 1 megabyte per second, you would use a delay of 1 ms. If you want to gate it to 512 kilobyte per second, then use a delay of 2 ms. For 256 kilobytes per second, use a delay of 4 ms.

    Keep in mind that bandwidth is often measured in bits per second rather than bytes per second. So if your goal is to measure things in bits-per-second, then multiply each value by 8.