Re: per message databases, was antiphishing idea

On Nov 19, 2011, at 11:05 AM, John Levine wrote:

>> The receiving MTA would look for something like 
>> '12345-gmail.com._msgids.paypal.com'
>> 
>> It looks up the message ID in a zone related to the From address, NOT 
>> the zone related to the message id.
> 
> I think we need a new category of FUSSP for anything that requires the
> sender to maintain a public per-message database of all the messages
> it's sent.  To put it mildly, this really REALLY doesn't scale.


As a thought experiment, if every sender offered a POP3-esque service
rather than sending mail by SMTP, it would require about the same amount
of resources as the receivers are providing today to manage that same
traffic, and that's not unreasonable.

A database of just recent messages sent would require less resources than
that.

Cheers,
  Steve