economics of spam (Re: A Trial Balloon to Ban Email?)

[John R. Levine]

> In practice, the organisation would simply bulk-mail their mailout
> without any hashcash stamps. But they WON'T be rejected as spam by
> the recipients, because the recipients, having deliberately opted
> in, will have told their email clients to accept mail from that
> particular address without stamps.
>
> No?

No.  Spammers, not being entirely stupid, will start sending spam with
return addresses that they guess are on your whitelist.  Even if they
guess wrong most of the time, the havoc this will wreak on the e-mail
system is enormous.  (Challenge/response systems are a dreadful idea
for the same reason.)

Sure, you could fix that problem by putting cryptographically
verifiable signatures on all mail, but we all know how likely that is.
Of course, the fact that despite a decade of significant effort,
nobody has the faintest idea how to implement a micropayment system
makes the whole argument rather academic.

Regards,
John Levine, johnl at iecc.com, Primary Perpetrator of "The Internet for Dummies",
Information Superhighwayman wanna-be, http://iecc.com/johnl, Sewer Commissioner
"I dropped the toothpaste", said Tom, crestfallenly.


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