【正文】 )Authentication andkey establishmentDistribution ofauthenticationvectors from HEto SNCompute CK(i) and IK(i),thenKasme(i)21EPSAKA? IfthekeysCK,IKresultingfromanEPSAKArunwerestoredinthefieldsalreadyavailableontheUSIMforstoringkeysCKandIKthiscouldleadtooverwritingkeysresultingfromanearlierrunofUMTSAKA.ThiswouldleadtoproblemswhenEPSsecurity contextandUMTSsecurity contextwereheldsimultaneously(asisthecasewhensecurity contextisstored.forthepurposesofIdleModeSignalingReduction).? Therefore,plasticroamingwhereaUICCisinsertedintoanotherMEwillnecessitateanEPSAKAauthenticationruniftheUSIMdoesnotsupportEMMparametersstorage.– 也就是說，在 EPSAKA過程中產(chǎn)生的 CK,IK不能存貯于 USIM中存貯 UMTSAKA產(chǎn)生的 CK,IK的地方。 USIM應(yīng)當(dāng)為 EPSAKA的 CK,IK使用獨(dú)立的 Files。若 USIM不支持 EMMFile，則EPSCK,IK必須存貯在 ME中。這就說明，當(dāng) USIM不支持EMMFiles，當(dāng) USIM卡換 ME時，則必須要執(zhí)行 EPSAKA過程。EPSAuthenticationVector說明 Kasme不是由 MME產(chǎn)生的，而是由 HE直接產(chǎn)生的EPSAV(4)RANDUMTSAV(5) GERANAV(3)XRESAUTNKasme CK IK KcEPSuserauthentication(EPSAKA)24UMTSHSSAMF RANDSQN Kf1 f2 f3 f4 f5MACXRES CK IKAKAMFSQN SQN(+)AKAMFMACMAC認(rèn)證向量五元組認(rèn)證令牌認(rèn)證算法認(rèn)證配置RAND AUTNHSS25UMTSUERANDKf1 f2 f3 f4 f5XMACRESCK IKSQN(+)AK 雙向認(rèn)證認(rèn)證令牌及隨機(jī)數(shù)AMF MACSQNAK認(rèn)證算法MACUSIMMEME26EPSHSSAMF RANDSQN Kf1 f2 f3 f4 f5MACXRESCK IK AKAMFSQN SQN(+)AKAMFMACMAC認(rèn)證向量四元組認(rèn)證令牌認(rèn)證算法認(rèn)證配置RAND AUTNSNIdKasmeHSS27EPSUERANDKf1 f2 f3 f4 f5XMACRESCK IKSQN(+)AK 雙向認(rèn)證認(rèn)證令牌及隨機(jī)數(shù)AMF MACSQNAK認(rèn)證算法MACUSIMSNId KasmeMEME28DifferentservingworkdomainsMME MMESGSNAn SGSN may forward unused UMTS authentication vectors to an MME UMTS AVs which were previously stored in the MME may be forwarded back towards the same SGSN. UMTS AVs which were previously stored in the MME shall not be forwarded towards other SGSNs.EPS authentication vectors shall not be forwarded from an MME towards an SGSN.Unused EPS authentication vectors shall not be distributed between MME39。s belonging to different serving domains (PLMNs)UMTS authentication vectors that were previously received from an SGSN shall not be forwarded between MME39。sOnlyEPSAVsinthesamePLMNOnlyUMTSAVsinthesameSGSNOnlyUMTSAVsinthesamePLMN2930MMEHSS CK,IKKDF256256SN id, SQN, ? AKKeNBKASME256KDFKDFKDF KDF256bitkeys KNASenc KNASint128bitkeys KNASenc KNASintTrunc Trunc256 256128 128256256256NASencalg,AlgIDNASintalg,AlgIDNAS UPLINK COUNTKDF KDF256bitkeys KRRCenc KRRCint128bitkeys KRRCenc KRRCintTrunc Trunc256 256128 128256256RRCencalg,AlgIDRRCintalg,AlgIDUPencalg,AlgID256256Physical cell ID, EARFCNDL256KeNBeNBeNBKeNB*KDFKUPencKUPenc256256128TruncKDFNHNHKeNB25631MECK,IKKDF256256SN id, SQN, ? AKKeNBKASME256KDFKDFKDF KDF256bitkeys KNASenc KNASint128bitkeys KNASenc KNASintTrunc Trunc256 256128 128256256256NASencalg,AlgIDNASintalg,AlgIDNAS UPLINK COUNTKDF KDF256bitkeys KRRCenc KRRCint128bitkeys KRRCenc KRRCintTrunc Trunc256 256128 128256256RRCencalg,AlgIDRRCintalg,AlgIDUPencalg,AlgID256Physical cell ID, EARFCNDL256256KeNB*KDFKUPencKUPencTrunc256128256KDF NHNHKeNB25632Kasme與 SNID? SNID=MCC+MNC? Kasme=f(CK,IK,SNid,SQN(+)AK)? Kasme的產(chǎn)生與 SNid有關(guān)，因此，當(dāng) SNid發(fā)生改變時，則原來的 Kasme不能使用。? 因此，在 InterPLMN的 TAU時，則必須要運(yùn)行 EPSAKA。NASCOUNTReset0??NASCount(復(fù)位）AKA. MappinginUTRAN/GERAN?EUTRANHO . MappinginUTRAN/GERAN?EUTRANidle Mobility TheNASCOUNTsshallnotberesetduringidlemodemobilityorhandoverforanalreadyexistingnativeEPSNASsecurity context.也就是說 NASCount快還返轉(zhuǎn)時，就要更換 Kasme了NAS? TheNASsecuritymodemandmessagefromMMEtoUEshallcontainthereplayedUEsecuritycapabilities,theselectedNASalgorithms,theeKSIforidentifyingKASME,andbothNONCEueandNONCEmmeinthecaseofcreatingamappedcontextinidlemobility.Thismessageshallbeintegrityprotected(butnotciphered)withNASintegritykeybasedonKASMEindicatedbytheeKSIinthemessage.? TheUEshallverifytheintegrityoftheNASsecuritymodemandmessage.ThisincludesensuringthattheUEsecuritycapabilitiessentbytheMMEmatchtheonesstoredintheUEtoensurethatthesewerenotmodifiedbyanattackerandcheckingtheintegrityprotectionusingtheindicatedNASintegrityalgorithmandtheNASintegritykeybasedonKASMEindicatedbytheeKSI.Inaddition,whencreatingamappedcontextforthecasedescribedinclause,theUEshallensurethereceivedNONCEUEisthesameastheNONCEUEsentintheTAURequestandalsocalculateK39。ASMEfromCK,IKandthetwononces(seeAnnex).? Ifsuccessfullyverified,theUEshallstartNASintegrityprotectionandciphering/decipheringwiththissecurity contextandsendstheNASsecuritymodepletemessagetoMMEcipheredandintegrityprotectedTheNASsecuritymodepletemessageshallincludeIMEIincaseMMErequesteditintheNASSMCCommandmessage.? TheMMEshalldecipherandchecktheintegrityprotectionontheNASSecurityModeCompleteusingthekeysandalgorithmsindicatedintheNASSecurityModeCommand.NASdownlinkcipheringattheMMEwiththissecurity contextshallstartafterreceivingtheNASsecuritymodepletemessage.NASuplinkdecipheringattheMMEwiththiscontextstartsaftersendingtheNASsecuritymodemandmessage.MME UENAS (UE , Selected NAS Algoritm, eKSI, IMEISV Request, NONCE