ETSI TS 133 401 V15.12.0 (2024-10)

Digital cellular telecommunications system (Phase 2+) (GSM); Universal Mobile Telecommunications System (UMTS); LTE; 3GPP System Architecture Evolution (SAE); Security architecture (3GPP TS 33.401 version 15.12.0 Release 15)

RTS/TSGS-0333401vfc0

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 3 - Security
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 17-Oct-2024

Standards Content (Sample)

TECHNICAL SPECIFICATION
Digital cellular telecommunications system (Phase 2+) (GSM);
Universal Mobile Telecommunications System (UMTS);
LTE;
3GPP System Architecture Evolution (SAE);
Security architecture
(3GPP TS 33.401 version 15.12.0 Release 15)

3GPP TS 33.401 version 15.12.0 Release 15 1 ETSI TS 133 401 V15.12.0 (2024-10)

Reference
RTS/TSGS-0333401vfc0
Keywords
GSM,LTE,UMTS
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ETSI
3GPP TS 33.401 version 15.12.0 Release 15 2 ETSI TS 133 401 V15.12.0 (2024-10)
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ETSI
3GPP TS 33.401 version 15.12.0 Release 15 3 ETSI TS 133 401 V15.12.0 (2024-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 10
1 Scope . 11
2 References . 11
3 Definitions, symbols and abbreviations . 13
3.1 Definitions . 13
3.2 Symbols . 14
3.3 Abbreviations . 15
3.4 Conventions . 16
4 Overview of Security Architecture . 17
5 Security Features . 17
5.1 User-to-Network security . 17
5.1.0 General . 17
5.1.1 User identity and device confidentiality . 18
5.1.2 Entity authentication . 18
5.1.3 User data and signalling data confidentiality . 18
5.1.3.1 Ciphering requirements . 18
5.1.3.2 Algorithm Identifier Values . 19
5.1.4 User data and signalling data integrity . 19
5.1.4.1 Integrity requirements . 19
5.1.4.2 Algorithm Identifier Values . 19
5.2 Security visibility and configurability . 20
5.3 Security requirements on eNodeB . 20
5.3.1 General . 20
5.3.2 Requirements for eNB setup and configuration . 20
5.3.3 Requirements for key management inside eNB . 21
5.3.4 Requirements for handling User plane data for the eNB . 21
5.3.4a Requirements for handling Control plane data for the eNB . 21
5.3.5 Requirements for secure environment of the eNB . 21
5.4 Void . 22
6 Security Procedures between UE and EPC Network Elements . 22
6.0 General . 22
6.1 Authentication and key agreement . 22
6.1.1 AKA procedure . 22
6.1.2 Distribution of authentication data from HSS to serving network . 23
6.1.3 User identification by a permanent identity . 24
6.1.4 Distribution of IMSI and authentication data within one serving network domain . 25
6.1.5 Distribution of IMSI and authentication data between different serving network domains. 26
6.1.6 Distribution of IMSI and UMTS authentication vectors between MMEs or between MME and
SGSN . 26
6.2 EPS key hierarchy . 27
6.3 EPS key identification . 29
6.4 Handling of EPS security contexts . 30
6.5 Handling of NAS COUNTs. 31
7 Security procedures between UE and EPS access network elements . 32
7.0 General . 32
7.1 Mechanism for user identity confidentiality . 32
7.2 Handling of user-related keys in E-UTRAN . 32
7.2.1 E-UTRAN key setting during AKA . 32
7.2.2 E-UTRAN key identification . 32
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7.2.3 E-UTRAN key lifetimes . 33
7.2.4 Security mode command procedure and algorithm negotiation . 33
7.2.4.1 Requirements for algorithm selection . 33
7.2.4.2 Procedures for AS algorithm selection . 34
7.2.4.2.1 Initial AS security context establishment . 34
7.2.4.2.2 X2-handover . 34
7.2.4.2.3 S1-handover . 34
7.2.4.2.4 Intra-eNB handover . 34
7.2.4.3 Procedures for NAS algorithm selection . 34
7.2.4.3.1 Initial NAS security context establishment . 34
7.2.4.3.2 MME change . 35
7.2.4.4 NAS security mode command procedure . 35
7.2.4.5 AS security mode command procedure . 36
7.2.4a Algorithm negotiation for unauthenticated UEs in LSM . 37
7.2.5 Key handling at state transitions to and away from EMM-DEREGISTERED . 38
7.2.5.1 Transition to EMM-DEREGISTERED . 38
7.2.5.2 Transition away from EMM-DEREGISTERED . 39
7.2.5.2.1 General . 39
7.2.5.2.2 With existing native EPS NAS security context . 39
7.2.5.2.3 With run of EPS AKA . 40
7.2.6 Key handling in ECM-IDLE to ECM-CONNECTED and ECM-CONNECTED to ECM-IDLE
transitio ns . 40
7.2.6.1 ECM-IDLE to ECM-CONNECTED transition. 40
7.2.6.2 Establishment of keys for cryptographically protected radio bearers . 40
7.2.6.3 ECM-CONNECTED to ECM-IDLE transition. 41
7.2.7 Key handling for the TAU procedure when registered in E-UTRAN . 41
7.2.8 Key handling in handover . 42
7.2.8.1 General . 42
7.2.8.1.1 Access stratum . 42
7.2.8.1.2 Non access stratum . 43
7.2.8.2 Void. 43
7.2.8.3 Key derivations for context modification procedure . 43
7.2.8.4 Key derivations during handovers . 44
7.2.8.4.1 Intra-eNB Handover . 44
7.2.8.4.2 X2-handover . 44
7.2.8.4.3 S1-Handover . 44
7.2.8.4.4 UE handling . 45
7.2.9 Key-change-on-the fly . 45
7.2.9.1 General . 45
7.2.9.2 K re-keying . 45
eNB
7.2.9.3 KeNB refresh . 46
7.2.9.4 NAS key re-keying . 46
7.2.10 Rules on Concurrent Running of Security Procedures . 46
7.2.11 Suspend and resume of RRC connection . 47
7.2.11.1 General . 47
7.2.11.2 RRC connection suspend . 47
7.2.11.3 RRC connection resume to a new eNB . 48
7.2.11.4 RRC connection resume to the same eNB . 49
7.3 UP security mechanisms . 50
7.3.1 UP confidentiality mechanisms . 50
7.3.2 UP integrity mechanisms . 50
7.4 RRC security mechanisms . 50
7.4.1 RRC integrity mechanisms . 50
7.4.2 RRC confidentiality mechanisms . 51
7.4.3 K * and Token Preparation for the RRCConnectionRe-establishment Procedure . 51
eNB
7.4.4 RRCConnectionRe-establishment Procedure for Control Plane CIoT EPS optimisation . 52
7.4.5 RRC UE capability transfer procedure . 53
7.5 Signalling procedure for periodic local authentication . 53
8 Security mechanisms for non-access stratum signalling and data via MME . 54
8.0 General . 54
8.1 NAS integrity mechanisms . 54
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8.1.1 NAS input parameters and mechanism . 54
8.1.2 NAS integrity activation . 54
8.2 NAS confidentiality mechanisms . 55
9 Security interworking between E-UTRAN and UTRAN . 55
9.1 RAU and TAU procedures . 55
9.1.1 RAU procedures in UTRAN . 55
9.1.2 TAU procedures in E-UTRAN . 56
9.2 Handover . 58
9.2.1 From E-UTRAN to UTRAN . 58
9.2.2 From UTRAN to E-UTRAN . 59
9.2.2.1 Procedure . 59
9.2.2.2 Derivation of NAS keys and K during Handover from UTRAN to E-UTRAN . 63
eNB
9.3 Recommendations on AKA at IRAT-mobility to E-UTRAN . 63
9.4 Attach procedures . 64
9.4.1 Attach in UTRAN . 64
10 Security interworking between E-UTRAN and GERAN . 64
10.1 General . 64
10.2 RAU and TAU procedures . 65
10.2.1 RAU procedures in GERAN . 65
10.2.2 TAU procedures in E-UTRAN . 65
10.3 Handover . 65
10.3.1 From E-UTRAN to GERAN . 65
10.3.2 From GERAN to E-UTRAN . 65
10.3.2.1 Procedures . 65
10.4 Recommendations on AKA at IRAT-mobility to E-UTRAN . 65
10.5 Attach procedures . 66
10.5.1 Attach in GERAN . 66
11 Network Domain Control Plane protection . 66
12 Backhaul link user plane protection . 66
13 Management plane protection over the S1 interface . 67
14 SRVCC between E-UTRAN and Circuit Switched UTRAN/GERAN . 68
14.1 From E-UTRAN to Circuit Switched UTRAN/GERAN . 68
14.2 Emergency call in SRVCC from E-UTRAN to circuit switched UTRAN/GERAN . 69
14.3 SRVCC from circuit switched UTRAN/GERAN to E-UTRAN . 69
14.3.1 Procedure . 69
15 Security Aspects of IMS Emergency Session Handling . 72
15.1 General . 72
15.2 Security procedures and their applicability . 73
15.2.1 Authenticated IMS Emergency Sessions . 73
15.2.1.1 General . 73
15.2.1.2 UE and MME share a current security context . 73
15.2.2 Unauthenticated IMS Emergency Sessions . 74
15.2.2.1 General . 74
15.2.2.2 UE and MME share no security context . 75
15.2.3 Void . 76
15.2.4 Key generation procedures for unauthenticated IMS Emergency Sessions . 76
15.2.4.1 General . 76
15.2.4.2 Handover . 76
16 Void . 76
Annex A (normative): Key derivation functions . 77
A.1 KDF interface and input parameter construction . 77
A.1.1 General . 77
A.1.2 FC value allocations . 77
A.2 K derivation function . 77
ASME
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A.3 K derivation function . 78
eNB
A.4 NH derivation function . 78
A.5 K * derivation function . 78
eNB
A.6 Void . 78
A.7 Algorithm key derivation functions . 79
A.8 KASME to CK', IK' derivation at handover . 79
A.9 NAS token derivation for inter-RAT mobility . 80
A.10 K’ from CK, IK derivation during handover . 80
ASME
A.11 K’ from CK, IK derivation during idle mode mobility . 80
ASME
A.12 K to CK , IK derivation . 81
ASME SRVCC SRVCC
A.13 K to CK', IK' derivation at idle mobility . 81
ASME
A.14 (Void) . 81
A.15 Derivation of S-K or S-K for dual connectivity . 81
eNB gNB
A.16 Derivation of LWIP-PSK . 81
A.17 Derivation of K_n for IOPS subscriber key separation . 82
A.18 Derivation of S-K for LWA . 82
WT
A.19 Key derivation function for key used in algorithms between UE and SgNB . 82
Annex B (normative): Algorithms for ciphering and integrity protection . 83
B.0 Null ciphering and integrity protection algorithms . 83
B.1 128-bit ciphering algorithm . 83
B.1.1 Inputs and outputs . 83
B.1.2 128-EEA1 . 84
B.1.3 128-EEA2 . 84
B.1.4 128-EEA3 . 84
B.2 128-Bit integrity algorithm . 85
B.2.1 Inputs and outputs . 85
B.2.2 128-EIA1 . 85
B.2.3 128-EIA2 . 85
B.2.4 128-EIA3 . 86
Annex C (informative): Algorithm test data . 87
C.1 128-EEA2 . 87
C.1.1 Test Set 1 . 87
C.1.2 Test Set 2 . 88
C.1.3 Test Set 3 . 89
C.1.4 Test Set 4 . 89
C.1.5 Test Set 5 . 90
C.1.6 Test Set 6 . 91
C.2 128-EIA2 . 94
C.2.1 Test Set 1 . 95
C.2.2 Test Set 2 . 96
C.2.3 Test Set 3 . 97
C.2.4 Test Set 4 . 98
C.2.5 Test Set 5 . 99
C.2.6 Test Set 6 . 100
C.2.7 Test Set 7 . 102
C.2.8 Test Set 8 . 104
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C.3 128-EEA1 . 116
C.4 128-EIA1 . 116
C.4.1 Test Set 1 . 116
C.4.2 Test Set 2 . 117
C.4.3 Test Set 3 . 117
C.4.4 Test Set 4 . 117
C.4.5 Test Set 5 . 118
C.4.6 Test Set 6 . 118
C.4.7 Test Set 7 . 118
Annex D (normative): Security for Relay Node Architectures . 121
D.1 Introduction . 121
D.2 Solution . 121
D.2.1 General . 121
D.2.2 Security Procedures . 121
D.2.3 USIM Binding Aspects . 124
D.2.4 Enrolment procedures for RNs . 124
D.2.5 Secure management procedures for RNs . 125
D.2.6 Certificate and subscription handling . 125
D.3 Secure channel profiles . 127
D.3.1 General . 127
D.3.2 APDU secure channel profile . 127
D.3.3 Key agreement based on certificate exchange . 127
D.3.3.1 TLS profile. 127
D.3.3.2 Common profile for RN and UICC certificate . 127
D.3.3.3 RN certificate profile . 128
D.3.3.4 UICC certificate profile . 128
D.3.4 Key agreement for pre-shared key (psk) case. 128
D.3.5 Identities used in key agreement . 128
Annex E (normative): Dual connectivity. 130
E.1 Introduction . 130
E.1.1 General . 130
E.1.2 Dual Connectivity architecture with an SeNB . 130
E.1.3 Dual Connec
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