userstats-bridge-transport.html says that bridge users come from counting requests (not responses)

[dcf]

​https://metrics.torproject.org/userstats-bridge-transport.html (​archive) says "These numbers are derived from directory requests counted on bridges."

But #18203 says that bridge estimate come from counting responses, not requests: "We're using the number of responses to estimate bridge users but the number of requests to estimate direct users."

[karsten]

Technically, you're right that bridge users are derived from the descriptor line containing directory responses, not the line containing directory requests. Which is different from relay users which are derived from the descriptor line containing directory requests.

However, the numbers are really the same, with minor differences being the result of binning. Both lines only contain requests that the directory could answer with a 200 OK status code. And even responses contain all responses that the directory decided to send back to the client, at the time of making that decision, regardless of how far it got with delivering the actual data.

So, regarding the phrasing on the Tor Metrics website I guess we should aim for picking terms that are least confusing to users. On the one hand I could imagine that "request" does not fully express that only requests are included for which the directory had a response. But on the other hand "response" might imply that the client received the full response and was able to use it, which is however not the case.

I'd say we stick with "requests" for both relay and bridge users to avoid confusions why the two metrics are based on different numbers. That's really a technical detail that very few Tor Metrics users will care about. We can still go into much more detail in the specification that we're going to write for our new sponsor 13, activity 2.1.

What do you think? Does this make sense? Can we close this ticket as wontfix?

[dcf]

Sorry, this was a result of my confusion. I thought there was a material difference between requests and responses. But #18167 and comment:5:ticket:18203 show that there is no real difference.