Re: filtering spoofed addresses cheaply

one view is that the clue is in the core where it is too late to fix it. and the place it needs to be fixed is at the edges, where the tools are weak and the clues seem (given empirical evidence) too few and far apart. this will change very slowly as market forces move clue toward the edges (on the backs of flying pigs) or the edges wither. another view is that the site of the cause is not where the pain of the effect is felt. hence the incentive to fix is small. this would seem only susceptible to vigilante acts, which is not cool. better ideas welcome. randy