Re: Protocol Wanted!!

[mpd@netcom.com (Mike Duvos)]

Peter Murphy <pkm@maths.uq.oz.au> writes:

 > Of the several problems stated above, I find the pricing
 > protocol the easiest to deal with. There are a few things
 > that need to be known. For example, what is the complexity
 > of Bob's algorithm? Does it do it in polynomial time or
 > (even better) some variant of logarithmic time? The cost
 > should bear relation to this fact.

[Thud](Sound of Bruce Henderson fainting) This is an interesting
perspective.  I would find myself arguing almost the opposite. It
would seem to me that the price one charges for a product or
service should depend only on its value to ones clients.  Not
upon ones cost to produce it.

If the value of your product to your customers is $100,000, then
the price should be $100,000 regardless of whether it costs you
$1 or $10,000 to make.

 > The cost should also be related to the number of bytes in
 > the message.

I'm not sure about this either.  A short message about a hidden
bomb which reads "under your chair" is infinitely more valuable
than a lengthy message containing the last six months of postings
to rec.pets.cats.

Once Bob gives Alice the factors, all messages encrypted with
that RSA public key can be decrypted, so the number of messages
and the length of each aren't really an issue. Bob could keep the
factors and sell Alice the plaintext of individual messages, but
this requires a continuing business relationship which the
anonymous Bob may not want.

If the messages contain confidential information, Alice may not
want Bob to see them.  Since Alice is paying Bob big bucks to
factor the key, it is unlikely Alice would agree to let Bob keep
the factors to himself.

-- 
     Mike Duvos         $    PGP 2.6 Public Key available     $
     mpd@netcom.com     $    via Finger.                      $