On Wed, Jun 04, 2003 at 02:55:29PM +0300, Jari Arkko wrote: > I don't have a good suggestion on how to resolve this, however. > Perhaps the lowest common denominator is still a big enough > deterrent? Note that help from a network entity is not likely > solve this problem. Think about it: the average users are > not going to install their own network helpers. They are going > to rely ISPs' servers. So, we'd see SMTP servers that do the > number crunching on behalf of the ISP's customers. Enter a > spammer who claims to have a small device... The ISP will have its own constraints about CPU time available to it. So the ISP will almost certainly want to charge for the service calculating the hashcash; and since this would only be necessary when first contacting someone initially, this should be acceptable to most people.... unless you want to contact hundreds of thousands of people for the first time from your PDA. But I can't think of anyone besides spammer who would want to do that, so that would seem to be an acceptable outcome. - Ted