Matt F. taught me how to modify Fiddler so that you can simulate DSL speeds:
1. Open Fiddler
2. Select Rules > Customize Rules…
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3. CustomRules.js will open in a text editor. Modify the two values below. (Note: to find them quickly, you can search on the word “trickle.”)
Change
// Delay sends by 300ms per KB uploaded.
oSession["request-trickle-delay"] = "300";
To
// Delay sends by 300ms per KB uploaded.
// oSession["request-trickle-delay"] = "300";
// DSL
oSession["request-trickle-delay"] = "75";
Change
// Delay receives by 150ms per KB downloaded.
oSession["response-trickle-delay"] = "150";
To
// Delay receives by 150ms per KB downloaded.
// oSession["response-trickle-delay"] = "150";
// DSL
oSession["response-trickle-delay"] = "38";
4. Save and close custom rules.
You can now switch to DSL speeds in Fiddler by doing the following:
5. Rules > Performance > Simulate Modem Speeds
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