[tor-talk] Reasoning behind 10 minute circuit switch?

[Jacob Appelbaum]

> It was alas picked arbitrarily. As Nick notes, it used to be 30 seconds,
> and then when we started getting users, all the relays complained of
> running at 100% cpu handling circuit handshakes. We changed it to 10
> minutes, and the complaints went away -- at least until the botnet
> showed up.
>

As a side note - from some of my NSA research, we've found that PSC
(Persona Session Collection) happens in ten minute windows. That means
that a selector will trigger collection and that the collection on
related flows will last for around ten minutes.

Might be a good time to reconsider those circuit build times -
especially if the above is correct. Hard to know for sure but good to
disclose in any case.

Happy hacking,
Jacob