Due to the involvement of multiple intermediaries without trusted parties,
lack of proper regulations, and a complicated supply chain, ad impression
discrepancy affects online advertising. This issue causes up to 82billionannualrevenuelossforhonestparties.Thelosscanbesignificantlyreducedwithapreciseandtrusteddecentralizedmechanism.ThispaperpresentsAdChain,adecentralized,distributed,andverifiablesolutionthatdetectsandminimizesonlineadvertisementimpressiondiscrepancies.AdChainestablishestrustbyemployingmultipleindependentagentstoreceiveandrecordlog−leveldata,alongwithaconsensusprotocoltovalidateeachaddata.AdChainisscalable,efficient,andcompatiblewiththecurrentinfrastructure.Ourexperimentalevaluation,usingoverhalfamillionaddatapoints,identifiessystemparametersthatachieve98from20generateprofitscomparabletominersonmajorblockchainnetworkslikeBitcoin.