[camram-spam] Re: Microsoft publicly announces Penny Black PoW postage project

[Seth David Schoen]

Eric S. Johansson writes:

> Ben Laurie wrote:
> 
> >Richard Clayton wrote:
> >
> >>and in these schemes, where does our esteemed moderator get _his_ stamps
> >>from ? remember that not all bulk email is spam by any means...  or do
> >>we end up with whitelists all over the place and the focus of attacks
> >>moves to the ingress to the mailing lists :(
> >
> >
> >He uses the stamp that you generated. Each subscruber adds 
> >cryptography at metzdowd.com as an address they receive mail at. Done. 
> >Trivial.
> 
> take a look at my headers and you'll see a real example.
> 
> ---eric (No. 1 generator of stamps on the Internet)

It seems like one risk for hashcash is that, when mailing lists are
whitelisted, a spammer can then use the lists to amplify spam (which I
think is what Richard Clayton was suggesting above).  For instance,
you generated a single hashcash stamp for cryptography at metzdowd.com of
the same value as the stamp you generated for richard at highwayman.com.

That stamp would hypothetically induce metzdowd.com to send your
message to _all_ of the cryptography subscribers, all of whom have
hypothetically whitelisted the list.  That means that, if your message
were spam, you delivered it to the whole subscriber base at very low
cost.

Or does hashcash only help moderated mailing lists (where it "pays"
the moderator for her time)?  My current impression is that it will
benefit individual e-mail recipients but not help subscribers to large
unmoderated mailing lists.

-- 
Seth David Schoen <schoen at loyalty.org> | Very frankly, I am opposed to people
     http://www.loyalty.org/~schoen/   | being programmed by others.
     http://vitanuova.loyalty.org/     |     -- Fred Rogers (1928-2003),
                                       |        464 U.S. 417, 445 (1984)