[Greylist-users] Greylist gravy train ends in 3-6 months

Tor Slettnes tor at slett.net
Sat Jul 17 15:15:26 PDT 2004

On Jul 16, 2004, at 07:52, Regis Wilson wrote:

> 1.  Zombie machine downloads 10,000 email addresses and starts 
> delivering mail
> 2.  Zombie detects tempfail code and puts from, to, and timestamp in 
> redliver
>     queue
> 3.  Zombie is done mailing 10,000 emails, goes to redliver queue.  If 
> timestamp
>     is 1 hour, 1 minute old, redeliver using same from, to and IP.
> It took me 3 seconds to come up with this idea and algorithm.  Any 
> programmer
> could write it and test it within one hour.  The next virus or trojan 
> payload
> upgrades all the zombies and infects more new zombies.  Greylisting is 
> dead,
> long live greylisting!

This idea has been mentioned in various lists at times (e.g. 
'exim-users at exim.org').    What is needed, now that it is out in the 
open, is a defensive patent.  (Heck, maybe greylisting itself should be 
patented, Evan...?)

Problem is, a US patent application takes anywhere from $10,000 to 
$20,000 to file.  A world-wide patent (WIPO) about ten times that.  
This, according to a IP training class I just took at work, so there 
may be some attorney cost included here.


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