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Glasnost: Test if your ISP is shaping your traffic (mpi-sws.org)
73 points by drey on April 9, 2011 | hide | past | favorite | 12 comments



My results for Flash:

Your ISP appears to rate limit your FlashVideo downloads. In our tests, downloads using control flows achieved up to 6723 Kbps while downloads using FlashVideo achieved up to 9345 Kbps.

Your ISP appears to rate limit downloads on port 8080. In our tests, downloads on port 8080 achieved up to 9487 Kbps while downloads on port 42507 achieved up to 6723 Kbps.

Maybe I'm misunderstanding the tests, but if my flash downloads where being rate limited the control would be faster, not slower?

In case anyone's interested, I'm in the UK, my ISP is Virgin - it's a 10mbit cable line.


In this case, Virgin is giving higher priority to streaming video or lower priority to everything else. Traffic shaping works both ways.


Interesting, the shaping only seems to occur on port 8080 - standard port 80 traffic generally runs at near enough 10mbits for me.

Also the bit torrent test came back unshaped, I'd be interested to see what other Virgin UK users have.


Virgin have transparent caching proxies between you and the web, which may explain why some HTTP results were faster - they didn't have to leave the Virgin network.


Is it supposed to keep alternating between "Time to finish: 500 seconds" and "Waiting for transfer to finish"?


I think you can safely say that is "traffic shaping" or actually, this sounds like packet insertion. Comcast does this. They insert FIN packets into your stream which makes the host think that the client has terminated the connection and the stream is dropped. It's really %^#$^^ stupid because then you just reopen the connection and try again from the start, using more bandwidth.

Obviously, their concern is not bandwidth usage, but file sharing, which conflicts with their own content services.


Strangely enough it was doing that for the YouTube and SSH tests.


YouTube: competing media

SSH: can't deep packet inspect because it's encrypted, shape it just incase.


Requires Java, for those on mobile.


On desktop, but still not launching a Java app. Latency kills my browser.


You can also create your own tests for Glasnost.

Instructions here:

http://broadband.mpi-sws.org/transparency/createtest.html


emule - "undetermined" http://loki08.mpi-sws.mpg.de//bb//glasnost.php?protocol1=eMu...

bittorrent - "no packet shaping" http://loki08.mpi-sws.mpg.de//bb//glasnost.php?protocol1=Bit...

This is run from my Sprint cell phone in a 4G area. Pretty damn impressive, IMHO.




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