Ever have one of those days where you’re browsing along, everything is cool, but then it seems like whenever you try to watch YouTube or download, your speed suddenly plummets? Your ISP could be “shaping” your traffic, intentionally throttling your rates for certain kind of media. To test it out, you can try running this Glasnost test.

It lets you run a test based on the type of media you’re consuming. You can select to test your speed viewing Flash video, downloading a BitTorrent, accessing email, etc.

Some ISPs do limit by certain kinds of media and sometimes only at certain times of day. You might want to run the test at a few different points to compare the results.

The Glasnost site is getting a bunch of traffic itself right now so you bookmark it and check back later after its servers aren’t so slammed.

Glasnost: Test if your ISP is shaping your traffic [broadband.mpi-sws.org via Lifehacker]

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