Hi relay operators!
I want to let you know about two upcoming research projects by academic research groups. The tl;dr is that they're running relays to do certain measurements, and so far as we can tell the proposed methodology is safe enough and worthwhile enough, but we invite you (and everybody) to evaluate it too.
If you didn't already know about the Tor Research Safety Board, now you do: https://research.torproject.org/safetyboard.html https://blog.torproject.org/blog/tor-heart-pets-and-privacy-research-communi... The board's goal is to help researchers do better and safer research, that is, to *minimize privacy risks while fostering a better understanding of the Tor network and its users*.
The board has been low-profile so far because it's just starting up, but now that we've handled six cases, I've put the details of some of these cases up on the safety board page: https://research.torproject.org/safetyboard.html#examples (Some of the cases are still anonymized because their paper is not yet finished or submitted or accepted.)
In particular, check out cases 2017-02 and 2017-03. They have each put up a web page explaining their research project and why it's safe, and listing which relays are associated with the research. http://tor.ccs.neu.edu/ https://onionpop.github.io/
Let us know if you have any questions. --Roger