> Okay, I read that, but I do not see where you offer any method to > account for other traffic that the relay being tested may be dealing with > at the time you are testing it. IOW, your testing procedure would be fine > if only the tor network, or at least each relay while it were being tested, > were entirely idle w.r.t. the traffic of other users. This is the same > defect that the authorities' testing procedures suffer from. > Do you have a solution to offer?

I guess it depends on what your goal is as to whether calling it a defect or not. For the test at hand, sure, we can't test as if no user activity would be ongoing but that's not too important if we want to test whether the advertised bandwidth significantly underestimates the true capacity of Tor relays.

I do not believe there is a defect, or at least I don't understand the stated concern. If by "other users", you mean the Tor users other than the speedtest client, then there is no problem because the relay's advertised bandwidth takes into account all Tor traffic, regardless of user. If, however, by "other users" you mean users of other applications running on the same machine as the relay, then (1) if such other traffic is relatively constant, then the measurement is correct as we want to measure the maximum available capacity *for Tor users*; but (2) if such non-Tor traffic comes in infrequent bursts, then it is true that such a burst may occur during a speedtest measurement and inaccurately indicate low capacity, but given that such bursts are infrequent, this problem should occur infrequently among all Tor relays.

Best, Aaron

nusenu:

The effect of these measurements is visible in significant (temporary) "increase" of adv. bw visible on metrics:

https://metrics.torproject.org/bandwidth.html?start=2021-04-20&end=2021-...

and on the OrNetStats per operator graphs, this is a good example:

https://nusenu.github.io/OrNetStats/emeraldonion.org.html https://nusenu.github.io/OrNetStats/#proven-operator-domains

For what it is worth: the experiment stopped at around 2021-06-05 00:00:00 UTC. The advertised bandwidth will decrease slowly and should be without any influence from the experiment again later this week.

If you want to follow currently running experiments on the network (or want to read up on past ones) we have created an entry, Network Experiments, on our status page[1] showing whether experiments are currently running or not.

Clicking there on "Network Experiments" should get you to the list[2] of currently running and past experiments providing explanations as to how long the experiments are already running/ran and what they are/were doing.

Let us know of any improvements to that Network Experiments part you think we should make. We are still experimenting with it.

Georg

[1] https://status.torproject.org/ [2] https://status.torproject.org/affected/network-experiments/