Glasnost

Summary

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.

Description

The goal of our Glasnost project is to make access networks, such as residential cable, DSL, and cellular broadband networks, more transparent to their customers.

ISPs are increasingly deploying a variety of middleboxes (e.g., firewalls, traffic shapers, censors, and redirectors) to monitor and to manipulate the performance of user applications. Most ISPs do not reveal the details of their network deployments to their customers. We believe that this knowledge is important to help users make a more informed choice of their ISP. Further, such knowledge is also useful for researchers designing protocols and systems that run on top of these networks.

To improve network transparency, we are building online tools that are easy to use and publishing them on this web page. Currently, there are two tools you could use to test your ISP. We will release more tools as we develop them in the future.

Our test focuses on the popular BitTorrent protocol as many ISPs are suspected to manipulate BitTorrent traffic. This type of traffic can be identified by the port it is sent on (e.g., TCP port 6881) or by BitTorrent content headers which occur in the packets. Therefore, we designed our online tool to detect whether your ISP is using one of the following techniques:

• Throttling all BitTorrent traffic.
• Throttling all traffic at well-known BitTorrent ports.
• Throttling BitTorrent traffic only at well-known BitTorrent ports.

Note that some ISPs do not throttle all BitTorrent traffic but only if this traffic exceeds a certain threshold. Thus, passing our tests does not necessary mean that there is no throttling occurring on your link.