Internet speed fingerprinting

This may be more a Tor than a Whonix-related question.

I had the following thought lately: is it possible to fingerprint Tor users by monitoring their internet speed?

Example: let’s take a 10 mbit/s vs a 100 mbit/s internet speed. Will the 100 mbit/s connection reach higher speed on Tor? Or does the Tor network have built-in speed limitations regardless of the client’s own internet connection speed?

If not, can the clients be fingerprinted by looking at their speed connection? I.e. if a Tor user is showing constant higher speeds, can his internet speed connection be inferred, and can it be used to single him out (as in: some Tor circuits at specific times with this specific entry guard are constantly showing higher speeds than other circuits, therefore it is probably the same user/set of users).

It may be a very noobish question, but it got me a bit confused…

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Good day,

While some servers may hypothetically store ping as part of their log files, this metric is usually so inconsistent and not in any way reliable even just to supplement other tracking methods, that there would be neither a requirement, nor an advantage in actively masking it. Furthermore, it would be hard to accomplish in a sensable manner as you’d either slow down those whose ping is below a set threshold or limit those whose ping surpasses said limit.

Have a nice day,


Hello, thanks for your message and sorry for my late reply.

So if I understood correctly, there is a threshold for internet speed determined by the Tor network? Having a 10 mbit/s vs 100 mbit/s connection does not impact Tor speed for the end user? Is it right?

I am asking because I can see that for instance when using openvpn (directly, not through Tor), the upper limit is the “native” limit of my home internet connection speed. Someone eavesdropping on my VPN end point (for instance a remote server where I download a file) could easily infer my maximum internet speed. That’s what I meant with my question.

On the other hand, I have never experienced more than 1 MB/s of download speed with Tor, regardless of my native connection speed.

Tor is incapable of matching the line speed of fast connections, for at least two reasons.

  1. Data travelling through the Tor network typically traverse 3 hops (6 for onion services) to reach their destination, compared to OpenVPN servers that are only 1 hop.

  2. Tor relays have diverse performance and are run by volunteers, whereas VPN servers are mostly commercial, and the fast links are being paid for by a subscriber base.

If you want more detailed information, try the documentation page at Tor Project: http://expyuzz4wqqyqhjn.onion/docs/documentation.html.en

Thanks for your replies.

I had the opportunity to try with different internet speed (different ISP packages), and indeed I never exceeded 1 MB/s of download speed. On the other hand, I have the feeling that Tor was faster using a faster line… But it needs some serious testing.