Vidalia shows reachability-testing circuits (was Re: About bridges)

[Roger Dingledine <arma@xxxxxxx>]

On Sun, Dec 23, 2007 at 12:38:38PM -0500, lg2005@xxxxxxxxxxxxx wrote:
> I tried to setup a bridge on my home box, no problem, BUT I was
>surprised to see (in Vidalia) a circuit with my bridge as exitnode! The
>circuit was something like "node_1,node_2,$123456789ABCDEF"
> 
> $123456789ABCDEF was the ID of my bridge as shown in the Vidalia
>config panel.
> 
> In the right side of the Vidalia interface, there was information
>about node_1 and node_2 but nothing about $123456789ABCDEF.
> 
> So my question is: A bridge can be an exitnode? That looks strange
>for me! Is there any way to run a bridge that is NOT an exitnode?

What you are seeing are the "reachability test" circuits. They go from
you through the Tor network back to you, so we can make sure that your
relay is reachable from other relays. See also Section 2.1.3 of
https://www.torproject.org/svn/trunk/doc/spec/path-spec.txt

Options I can imagine:

a) get Vidalia to mark each circuit with its purpose, so it's easier to
know why those circuits are being displayed. This would involve some
hard thinking -- mostly to figure out a good interface that doesn't
clutter things even more.

b) get Vidalia to not display non-general-purpose circuits. That way
these circuits wouldn't show up on that map, so fewer people would ask
about them. Somewhat easier to do, but feels like we're hiding
potentially useful info from the users.

c) continue to answer this question a few times a year.

d) other ideas?

Thanks,
--Roger