Remailer REORDER not DELAY

Jim choate ravage at bga.com
Tue Jun 14 11:57:39 PDT 1994


> I belive the problem is that you can trace a message back to its source
> by anazyzing when the messages are sent. Let's say you're watching
> Angie's net connection because you think she is guilty of Thoughtcrime.
> At 12:34, Andie sends an encrypted message to soda. Say that soda hasn't
> received any messages for 5 hours before 10:14, then receives 4 between
> 10:15 and the time Angie's mailer connects to port 25 of soda's
> remailer. You wait until soda spits out 4 messages, then the 5th is
> Angie's. You do this through the entire remailer chani, and when Angie's
> message gets to its destination, you can see it, and trace it back to
> her.
>
You can also tell it comes from the remailer because it is encrypted to
allow you to verify exactly this. I am not interested in hiding the path
information, I *want* to certify where it came from - *not* who(!) is
sending it or *what* is in it. I can see not knowing or being able to
prove the pathway as a possible hole for interjecting bogus packets.

Now, about this re-sending issue. If I rcv. a packet at 10am and it
gets a random time-stamp there is no guarantee when it will be sent
other than within 24hrs. It may or may not be sent in the 5 hr. gap in
your example, no way to know really.

> This is bad.
> 
> Now, if soda had queued a few messages, then spit them out in random
> order in random chuinks, traffic analysis would be much less effective.
>
The random order is what does it, not the # of packets sent out. the
randomness in leaving the site is more important than how many.

> For examples of how evil traffic analysis can be, just watch a few
> episodes of Deep Space Nine. I shudder whenever Otto says "Quark, you
> have sent 5 messages to the Romulan high command this week." or whatever.
>
Excuse me?.....DS9?...

> Jer
> 
> darklord at cmu.edu | "it's not a matter of rights  / it's just a matter of war
> finger me for my |  don't have a reason to fight / they never had one before"
>    Geek Code and |                                    -Ministry, "Hero"
>   PGP public key | http://www.cs.cmu.edu:8001/afs/andrew.cmu.edu/usr25/jbde/
> 






More information about the cypherpunks-legacy mailing list