简介:Intoday'sInternetcomputingworld,illegalactivitiesbycrackersposeaseriousthreattocomputersecurity.Itiswellknownthatcomputerviruses,Trojanhorsesandotherintrusiveprogramsmaycausesevereandoftencatastrophicconsequences.Thispaperproposesanovelsecurecomputerarchitecturebasedonsecurity-code.Everyinstruction/datawordisaddedwithasecurity-codedenotingitssecuritylevel.Externalprogramsanddataareautomaticallyaddedwithsecurity-codebyhardwarewhenenteringacomputersystem.Instructionwithlowersecurity-codecannotrunorprocessinstruction/datawithhighersecuritylevel.Security-codecannotbemodifiedbynormalinstruction.Withminorhardwareoverhead,thenewarchitecturecaneffectivelyprotectthemaincomputersystemfromdestructionortheftbyintrusiveprogramssuchascomputerviruses.FormostPCsystems,itincludesanincreaseofword-lengthby1bitonregisters,thememoryandtheharddisk.