Re: peculiar server "bandwidth" posted by server "mnl" and possible new type of attack

["Kasimir Gabert" <kasimir.g@xxxxxxxxx>]

On Wed, Sep 10, 2008 at 7:28 AM, Scott Bennett <bennett@xxxxxxxxxx> wrote:
>>
>>The fact of not being an exit node would make it a better corruped
>>relay? I mean, if I would like to DOS the Tor network I would be better
>
>     No, or at least I don't think so.  What I was referring to is that most
> of the trouble we've had from bad operators has taken the form of corrupted
> exit servers, where what goes into or comes out of the exit is in the clear
> and can be altered before it is sent where it is going.
>
>>to set the trojan node as internal?
>>
>     For this kind of attack, I suppose there might be some sort of advantage
> to being only a relay and not an exit because route selection often prefers
> non-exit relays for non-exit positions in a route, and a typical route has
> two non-exit positions but only one exit position.  So the chances to bog
> down performance might be a bit higher if the attacker focused on non-exit
> usage.
>     But Roger has already said that clients believe that no server really
> handles more than 5 MB/s, so they trim any figures greater than that back to
> 5 MB/s.  If you had a dozen or two tor servers falsely reporting high usages,
> each at 5 MB/s or more, it might make a mess of things because they would
> distort the networkwide statistics, especially if those servers did not
> identify themselves as all being members of the same Family.

For reference, the reported bandwidth values from mnl hover around
2000 KB/s, but are very flaky (I'll assume this is caused by the
connection issues Domenico was talking about).

http://trunk.torstatus.kgprog.com/router_detail.php?FP=abd38668d3f476f50232fec0b6db6550ea43edd0

Kasimir

>
>
>                                  Scott Bennett, Comm. ASMELG, CFIAG
> **********************************************************************
> * Internet:       bennett at cs.niu.edu                              *
> *--------------------------------------------------------------------*
> * "A well regulated and disciplined militia, is at all times a good  *
> * objection to the introduction of that bane of all free governments *
> * -- a standing army."                                               *
> *    -- Gov. John Hancock, New York Journal, 28 January 1790         *
> **********************************************************************
>



-- 
Kasimir Gabert