有线数字电视讲座第三讲-数字电视的条件接收系统-上

200413CHINACABLETELEVISION□225321TN949.197E1007-7022200413-0072-0711CAConditionalAccessCACACASConditionalAccessSystemCACACA2001CA62CA20037SMSSubscriberManagementSystemCAS10CASChinacryptDVBv3.2.1CASCAS/SMSCASCASCATVCASVODInternetCAS1CAS3CAS312327CADTVCableDigitalTelevisionCACADTVCADTVCASCADTVCASSTBSet-Top-BoxCADTVCADTV2CAS6CASCAS61CAS2CASCASCAS3CA456CASSTB3CA/CASCASCADTVCA/31CADTV2CADTVSTB3CASCADTVCASCASCADTVCACATVCASCATVCA11CA1CASChannelScrambingCAS1CASCAS1CATVCAS2CAS372004133CASCACATVSTBCACASSTB1152004CACACATV2CASContentEncryptionCASCWContentWordCWCASCATVCASDVBDigitalVideoBroadcastingSimulCryptCASDVBCASSTBCAPIDPacketIdentifierPID3CASMulti-EncryptionSTBCASSTBSTBCAS4CASAlgorithmRenewableCASCASTBDVBMultiCryptOpenCablePODPointofDeploySTBCASCASPODCACATV5CASCATVSBASoftwareDefinedBroadbandAccessI/O/DSPCPUCA/CMCableModemModemMPEGCAPODCASCA/PlatformCASCACACACAS47200413123PublicKeyEncryptionSecretKeyEncryption1SessionKeyRC4DES2RSARSAR.RivestA.ShamirL.Adleman1977RSA31982RSARSADataSecurityInc.RSAPublicKeyPrivatcKey1RSARSA100①pqn=p×q②eep-1×q-1③Euclidde×d=1modp-1×q-1nd④nendpqmmmlm2mis2ˆs≤nsci=miˆemodnami=ciˆdmodnbRSAabmHASHpqn=p×qRSAenpqdRSApq1002RSARSAnendnpqRSAnRSARSA512bn19971998768bn1024bn2048bnRSA768bn2004572004133RSA2CASDESDESXTripleDESRSARriestRC2RC4RC5RC2RC5RC4DESRSADESDESRSA4CASCASCASCWKeyPairCWCWCWCWCWCWCWCWCASCASCACAS/2CASCWGSMSSASSubscriberAuthorizedSystemEMMEntitlementManagementMessageEMMECMEntitlementControlMessageSTBSTBSMSSASEMMCWGCWEMMECMECMDVBCWECMEMMCATVSTBECMEMMECMEMMCWCWSTB67200413CWCWGCWCW1CAS1ECMEMMEMMSASEMMEMMEMMECMSCSCWECMSCSMUXEISECMSCSACAccessCriteriaCAACECMGECMACSCSSCSCAECMG2CACAECMEMMSimulCryptPODCASECMEMMCWSTBSTBCWEPGElectronicProgramGuidesCASCAEPGVPN3CASCAS①CACADTVSIServiceInformatiomSIMITSDTCASEPGCollectionEISPSIGPSIProgramSpecificInformationPSI4PMTPIDPIDPIDPATPMTNITCATCAECMPIDPSIGCPSIGCACACASystem-IDPSICATMUXTSSTBService-IDTSPSICATEMM-PIDEMMSTBEMMECMCWCWCAACSCSSCSCAACECMGSCSCWGCWECMGECMGECMSCSSCSMUXECMCWMUXECMTSSTBEISMUXCMUXCMUXMUX772004133CASEMMGSMSEMMEMMEMMMUXMUXEMMTSSTBECMEMMEMMECMSKServiceKeySKECMCWCWSTBCW②CACAVAMVODAccessManager&ControllerVODVAMOESOESOn-DemandEntitlementServerVAMEMMVAMOESEMMOESEMMGMUXOESEMMVAMVAMSTBEMMSTBCWCAS32003-11-198888888888888888888888888888888888888888888888884□1651102001GW-500Q803Q804Q809120VQ1C3153R551ΩR52AST-145min85VC817100µF/100V3GW-500Q310⑤R829R82947Ω4AST-ECD1Q60850VQ608TDA2595○1’0V12VTDA2595○1’R646150Ω2004-04-1687200413