A Trial Balloon to Ban Email?

Matt Crawford crawdad at fnal.gov
Mon May 12 09:53:25 EDT 2003


> The computational task can get arbitrarily larger, if the recipient
> system doesn't like the look of the mail.  I can picture the MDA
> going, "wow, I decrypted this one, but it scores 9.2 on my procmail
> filter scale, so I better ask for and get fifteen MIPS-minutes of CPU
> time before I actually deliver it."
> 
> Stuff like this can be done anonymously, can be done on the recipient
> and sender machines, can depend on filters (the MDA sees it after it
> arrives and gets decrypted) and limits the per-machine rate at which a
> spammer can send spam.

This doesn't fit Joe Lunchbox's current model in which he dumps his
outgoing mail onto his provider's server and turns off his machine.
His provider either has to deliver synchronously and bounce the
computational payment burden back to Joe, pay it for him, or bounce
the message.  In the latter case, the receiver who demanded cycles
needs to recognize the problem it set and accept the answer on a
later date.
			Matt Crawford

---------------------------------------------------------------------
The Cryptography Mailing List
Unsubscribe by sending "unsubscribe cryptography" to majordomo at metzdowd.com



More information about the cryptography mailing list