[via/test your connection at Glasnost]
Certain ISPs have been shown to rate limit or block BitTorrent traffic sent by their customers. While there are multiple reports of this on the web, only a few ISPs have admitted that they manipulate BitTorrent traffic. And, to date, it is hard for users without networking expertise to gain evidence about the behavior of their ISP.
This test suite creates a BitTorrent-like transfer between your machine and our server, and determines whether or not your ISP is limiting such traffic. This is a first step towards making traffic manipulation by ISPs more transparent to their customers.