Welcome to GSoC project blog

Welcome to my Google Summer of Code (GSoC) project blog!

This project is about distributing the Tor directory for hidden service descriptors. Why that? Well, the simple answer is that the current solution does not scale. There may be an arbitrary number of hidden servers in the Tor network. But every hidden server needs to store a service descriptor on every directory servers (at the moment there are 5 in total). And all clients accessing a hidden server need to check one of these directory servers before establishing the connection. This may be okay for the moment, but the Tor network does not stop growing, so that "for the moment" is simply not enough.

The downside of the distribution is loss of authority over the directory (for hidden service descriptors, not router descriptors). Is this a problem? On first sight, no. Descriptors are self-signed and expire automatically after some hours and clients know the descriptor identifiers before accessing the service anyway. So what is the maximum damage that an adversary can cause? That a hidden service is unreachable. That means we have to talk about replication, Sybil attack, and trust. The approach may cause a degradation of the (at least in theory) 100% availability of hidden service descriptors. But we can try to make availability loss as small as possible to make it rather an academic issue than a practical problem.

If you like, you may want to read my full application for GSoC.

The purpose of this blog is to make the project as transparent as possible. I will try to post my thoughts and project progress regularly on this blog. This is both for documentation and as request for comments. If you have a new idea or find something completely stupid, drop me a comment and let's discuss it! Whenever there are final credits or something like that, you will be mentioned!

Just one word to my person: I am a PhD student at University of Bamberg, Germany. You can find more details on my university page (partly in German).

Summer can come!