Hashcash- A Denial of ServiceCounter-MeasureAdamBack
e-mail: adam@cypherspace.org1stAugust2002AbstractHashcashwasoriginally proposedasa mechanismto throttlesystematicabuseof un-meteredinternetresources
suchasemail,andanonymousremailersin May 1997. Five yearson, this papercapturesin oneplacethe various
applications,improvementssuggestedand relatedsubsequent publications, and describesinitial experience from
experimentsusinghashcash.ThehashcashCPUcost-functioncomputesa token which canbeusedasa pro
