[tor-dev] Information on the handling of relays churn

[Adrien Luxey]

Dear Tor developers,

As a PhD student in distributed systems, I am studying onion routing.

We would like to investigate an onion routing system that would run on
users devices, i.e. a lot of nodes with crappy bandwidth and
intermittent connection.
To compare against Tor, I have been looking for information about how
you currently handle the disconnection of relays, but I found no
"digest" on the Web. Your code seems to point to the direction of
core/or/circuit*, that I need to investigate further. I still would love
some first-hand high-level description from you guys.

I have the following questions:

  * When an OR disconnects while supporting active circuits, how is the
    failure detected?
  * How are the paths subsequently rebuilt?
  * To which extent would you say that Tor is resilient to churn? What
    would be the effects of a massive churn of relays? Where would be
    the bottleneck?

If you have any questions on my work, I will be pleased to answer
(though a little ashamed, because I know our system will never hold your
security properties so tight)!

With much respect for your work and philosophy,
Adrien Luxey

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.torproject.org/pipermail/tor-dev/attachments/20180927/45816c20/attachment-0001.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: OpenPGP digital signature
URL: <http://lists.torproject.org/pipermail/tor-dev/attachments/20180927/45816c20/attachment-0001.sig>