How does SwarmScreen improve my privacy?

[drchoffnes]

SwarmScreen protects you by hiding your real BitTorrent traffic in a sea of connections to randomly selected torrents. So that you don't look suspicious, SwarmScreen carefully adjusts random connections to appear the same as your real ones.

[andy]

My question is this: How effective is SwarmScreen at enhancing privacy? It seems to me - and I do not understand all the technical side - that if someone wants to know who is downloading torrent XYZ, they just need to see who is downloading it. I guess what I am saying is that I just do not understand how it works.

[drchoffnes]

That's a great question. You are right that someone need only 'look' at what you are downloading to identify your content. But this assumes that the content is unencrypted and there is a centralized way to do this. In BitTorrent, neither of these conditions is necessarily true.

As we show in our paper, though, even if you obscure the content you are downloading, it doesn't help if you download from someone else (which is always true in BitTorrent) and an observer can determine what that other person is downloading. In other words, you can be made guilty by association with someone else.

Swarmscreen prevents this guilt-by-association attack by hiding the content you are keeping among many concurrent downloads to content that you are not keeping. For more details on this work, you can see the technical report here: http://www.aqualab.cs.northwestern.edu/ ... een-TR.pdf