Re: [Asrg] About that e-postage draft [POSTAGE]

[Bart Schaefer <schaefer at brasslantern.com>]

On Feb 18,  1:06pm, Rich Kulawiec wrote:
} Subject: Re: [Asrg] About that e-postage draft [POSTAGE]
}
} On Sun, Feb 15, 2009 at 09:14:15AM -0600, mathew wrote:
} > Nonsense. You just make the purchased stamp dependent upon the address
} > of the recipient, for example by hashing the To: address inside the
} > cryptographic stamp when it's minted.
} 
} How's that going to work with forwarding, virtual user tables, and
} alias expansions?

It doesn't, by fiat.  The POSTAGE draft applies to an SMTP transaction,
not to an end-to-end transmission through all possible store-and-forwards
of a message from a sender to a recipient.

Maybe this oversimplifies it into uselessness, but that's how it's
structured.  It's an SMTP extension, not a format-of-internet-messages
extension.

} And how will it avoid leaking information when someone is BCC'd?

The crytpographic stamp doesn't need to survive the transaction any more
than the Bcc header itself does.