ETSI TS 123 501 V15.9.0 (2020-03)

ETSI TS 123 501 V15.9.0 (2020-03)






TECHNICAL SPECIFICATION
5G;
System architecture for the 5G System (5GS)
(3GPP TS 23.501 version 15.9.0 Release 15)

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3GPP TS 23.501 version 15.9.0 Release 15 1 ETSI TS 123 501 V15.9.0 (2020-03)



Reference
RTS/TSGS-0223501vf90
Keywords
5G
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3GPP TS 23.501 version 15.9.0 Release 15 2 ETSI TS 123 501 V15.9.0 (2020-03)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
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Legal Notice
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
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Modal verbs terminology
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"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TS 23.501 version 15.9.0 Release 15 3 ETSI TS 123 501 V15.9.0 (2020-03)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 12
1 Scope . 13
2 References . 13
3 Definitions and abbreviations . 16
3.1 Definitions . 16
3.2 Abbreviations . 18
4 Architecture model and concepts . 20
4.1 General concepts . 20
4.2 Architecture reference model . 21
4.2.1 General . 21
4.2.2 Network Functions and entities . 21
4.2.3 Non-roaming reference architecture . 22
4.2.4 Roaming reference architectures . 25
4.2.5 Data Storage architectures . 27
4.2.6 Service-based interfaces . 29
4.2.7 Reference points . 29
4.2.8 Support of non-3GPP access . 31
4.2.8.1 General Concepts to Support Non-3GPP Access . 31
4.2.8.2 Architecture Reference Model for Non-3GPP Accesses . 32
4.2.8.2.1 Non-roaming Architecture for Non-3GPP Accesses . 32
4.2.8.2.2 LBO Roaming Architecture for Non-3GPP Accesses, N3IWF in same PLMN as 3GPP access . 32
4.2.8.2.3 Home-routed Roaming Architecture for Non-3GPP Accesses, N3IWF in same PLMN as
3GPP access . 33
4.2.8.2.4 LBO Roaming Architecture for Non-3GPP Accesses, N3IWF in different PLMN from 3GPP
access . 34
4.2.8.2.5 Home-routed Roaming Architecture for Non-3GPP Accesses, N3IWF in different PLMN
from 3GPP access . 35
4.2.8.3 Non-3GPP Access Reference Points . 36
4.2.9 Network Analytics architecture . 36
4.3 Interworking with EPC . 37
4.3.1 Non-roaming architecture . 37
4.3.2 Roaming architecture . 38
4.3.3 Interworking between 5GC via non-3GPP access and E-UTRAN connected to EPC . 39
4.3.3.1 Non-roaming architecture . 39
4.3.3.2 Roaming architecture . 40
4.3.4 Interworking between ePDG connected to EPC and 5GS . 42
4.3.4.1 Non-roaming architecture . 42
4.3.4.2 Roaming architectures . 43
4.4 Specific services . 45
4.4.1 Public Warning System . 45
4.4.2 SMS over NAS . 45
4.4.2.1 Architecture to support SMS over NAS . 45
4.4.2.2 Reference point to support SMS over NAS . 47
4.4.2.3 Service based interface to support SMS over NAS . 47
4.4.3 IMS support . 47
4.4.4 Location services . 48
4.4.4.1 Architecture to support Location Services . 48
4.4.4.2 Reference point to support Location Services . 48
4.4.4.3 Service Based Interfaces to support Location Services . 49
4.4.5 Application Triggering Services . 49
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3GPP TS 23.501 version 15.9.0 Release 15 4 ETSI TS 123 501 V15.9.0 (2020-03)
5 High level features. 49
5.1 General . 49
5.2 Network Access Control . 49
5.2.1 General . 49
5.2.2 Network selection . 49
5.2.3 Identification and authentication . 50
5.2.4 Authorisation . 50
5.2.5 Access control and barring . 50
5.2.6 Policy control . 51
5.2.7 Lawful Interception. 51
5.3 Registration and Connection Management . 51
5.3.1 General . 51
5.3.2 Registration Management . 51
5.3.2.1 General . 51
5.3.2.2 5GS Registration Management states. 51
5.3.2.2.1 General . 51
5.3.2.2.2 RM-DEREGISTERED state . 51
5.3.2.2.3 RM-REGISTERED state . 52
5.3.2.2.4 5GS Registration Management State models . 52
5.3.2.3 Registration Area management . 53
5.3.2.4 Support of a UE registered over both 3GPP and Non-3GPP access . 53
5.3.3 Connection Management . 55
5.3.3.1 General . 55
5.3.3.2 5GS Connection Management states . 55
5.3.3.2.1 General . 55
5.3.3.2.2 CM-IDLE state . 55
5.3.3.2.3 CM-CONNECTED state . 56
5.3.3.2.4 5GS Connection Management State models . 56
5.3.3.2.5 CM-CONNECTED with RRC Inactive state . 57
5.3.3.3 NAS signalling connection management . 59
5.3.3.3.1 General . 59
5.3.3.3.2 NAS signalling connection establishment . 59
5.3.3.3.3 NAS signalling connection Release. 59
5.3.3.4 Support of a UE connected over both 3GPP and Non-3GPP access . 59
5.3.4 UE Mobility . 60
5.3.4.1 Mobility Restrictions . 60
5.3.4.1.1 General . 60
5.3.4.1.2 Management of Service Area Restrictions . 61
5.3.4.2 Mobility Pattern . 62
5.3.4.3 Radio Resource Management functions . 62
5.3.4.4 UE mobility event notification . 63
5.4 3GPP access specific aspects. 64
5.4.1 UE reachability in CM-IDLE. 64
5.4.1.1 General . 64
5.4.1.2 UE reachability allowing mobile terminated data while the UE is CM-IDLE . 65
5.4.1.3 Mobile Initiated Connection Only (MICO) mode . 65
5.4.2 UE reachability in CM-CONNECTED. 66
5.4.3 Paging strategy handling . 66
5.4.3.1 General . 66
5.4.3.2 Paging Policy Differentiation . 66
5.4.3.3 Paging Priority . 67
5.4.4 UE Radio Capability handling . 67
5.4.4.1 UE radio capability information storage in the AMF . 67
5.4.4.2 Void. 68
5.4.4.2a UE Radio Capability Match Request . 68
5.4.4.3 Paging assistance information . 68
5.4.4a UE MM Core Network Capability handling . 69
5.4.4b UE 5GSM Core Network Capability handling . 69
5.4.5 DRX (Discontinuous Reception) framework . 69
5.4.6 Core Network assistance information for RAN optimization . 70
5.4.6.1 General . 70
5.4.6.2 Core Network assisted RAN parameters tuning . 70
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3GPP TS 23.501 version 15.9.0 Release 15 5 ETSI TS 123 501 V15.9.0 (2020-03)
5.4.6.3 Core Network assisted RAN paging information . 70
5.4.7 NG-RAN location reporting . 71
5.5 Non-3GPP access specific aspects . 71
5.5.1 Registration Management . 71
5.5.2 Connection Management . 72
5.5.3 UE Reachability . 72
5.5.3.1 UE reachability in CM-IDLE . 72
5.5.3.2 UE reachability in CM-CONNECTED . 73
5.6 Session Management . 73
5.6.1 Overview . 73
5.6.2 Interaction between AMF and SMF . 75
5.6.3 Roaming . 76
5.6.4 Single PDU Session with multiple PDU Session Anchors . 77
5.6.4.1 General . 77
5.6.4.2 Usage of an UL Classifier for a PDU Session . 77
5.6.4.3 Usage of IPv6 multi-homing for a PDU Session. 78
5.6.5 Support for Local Area Data Network . 80
5.6.6 Secondary authentication/authorization by a DN-AAA server during the establishment of a PDU
Session . 82
5.6.7 Application Function influence on traffic routing . 83
5.6.8 Selective activation and deactivation of UP connection of existing PDU Session . 88
5.6.9 Session and Service Continuity . 89
5.6.9.1 General . 89
5.6.9.2 SSC mode . 89
5.6.9.2.1 SSC Mode 1 . 89
5.6.9.2.2 SSC Mode 2 . 89
5.6.9.2.3 SSC Mode 3 . 89
5.6.9.3 SSC mode selection. 90
5.6.10 Specific aspects of different PDU Session types . 90
5.6.10.1 Support of IP PDU Session type . 90
5.6.10.2 Support of Ethernet PDU Session type . 91
5.6.10.3 Support of Unstructured PDU Session type . 92
5.6.11 UE presence in Area of Interest reporting usage by SMF . 93
5.6.12 Use of Network Instance . 94
5.6.13 Always-on PDU session . 94
5.6.14 Support of Framed Routing . 95
5.7 QoS model . 95
5.7.1 General Overview . 95
5.7.1.1 QoS Flow . 95
5.7.1.2 QoS Profile . 96
5.7.1.3 Control of QoS Flows . 96
5.7.1.4 QoS Rules . 97
5.7.1.5 QoS Flow mapping . 97
5.7.1.6 DL traffic. 99
5.7.1.7 UL Traffic . 99
5.7.1.8 AMBR/MFBR enforcement and rate limitation . 100
5.7.1.9 Precedence Value . 100
5.7.2 5G QoS Parameters .
...