Hi everyone,

I just finished a new tech report titled "Counting daily bridge users":

https://research.torproject.org/techreports/counting-daily-bridge-users-2012...

From the abstract: "As part of the Tor Metrics Project, we want to learn

how many people use the Tor network on a daily basis. Counting users in an anonymity network is, obviously, a difficult task for which we cannot collect too sensitive usage data. We came up with a privacy-preserving approach for estimating directly connecting user numbers by counting requests to the directory mirrors and deriving approximate user numbers from there. In this report we describe a modified approach for estimating the number of users connecting via bridges by evaluating directory requests made to bridges. We compare this new approach to our current approach that estimates bridge user numbers from total unique IP addresses seen at bridges. We think that results from the new approach are closer to reality, even though that means there are significantly fewer daily bridge users than originally expected."

Feedback is much appreciated and could influence our implementation of user number estimates in the future (#7154).

Thanks, Karsten