At 09:45 PM 5/12/03 +0100, Adam Back wrote:
In addition it is expected that there would be a mechanism whereby regular correspondents would white list each other. (Probably automatically via their mail clients).
Whether you think a few seconds is sufficient depends on your views of the economics of spamming. Ie how close to losing break-even the spammers are, and whether a few seconds of CPU per message is enough to significantly increase the cost.
Two points. First, Joe Sixpack won't use it if it requires an extra click; but he might if the mail queueing is in the background. Second, spammers use trojans that establish local mail relays (!) You think they won't steal some cycles to pollute? Ok, three points. If you're sending from your PDA, either deal with the battery-life-loss as a cost of emailing from your PDA, or have your net-connected host do the work. Again, transparently, or no one will use it. Personally, I favor an Assasination Politics flavor solution, but that's unlikely to gain widespread favor :-)