Content for TS 29.536 Word version: 18.0.0
1 Scope
2 References
3 Definitions, abbreviations
3.1 Definitions
3.2 Abbreviations
4 Overview
4.1 General
4.2 NSAC support in roaming
...
...
1 Scope p. 8
The present document specifies the stage 3 protocol and data model for the Nnsacf Service Based Interface. It provides stage 3 protocol definitions and message flows, and specifies the API for each service offered by the NSACF.
The 5G System stage 2 architecture and procedures are specified in TS 23.501 and TS 23.502.
The Technical Realization of the Service Based Architecture and the Principles and Guidelines for Services Definition are specified in TS 29.500 and TS 29.501.
2 References p. 8
The following documents contain provisions which, through reference in this text, constitute provisions of the present document.
- References are either specific (identified by date of publication, edition number, version number, etc.) or non-specific.
- For a specific reference, subsequent revisions do not apply.
- For a non-specific reference, the latest version applies. In the case of a reference to a 3GPP document (including a GSM document), a non-specific reference implicitly refers to the latest version of that document in the same Release as the present document.
[1]
TR 21.905: "Vocabulary for 3GPP Specifications".
[2]
TS 23.501: "System Architecture for the 5G System; Stage 2".
[3]
TS 23.502: "Procedures for the 5G System; Stage 2".
[4]
TS 29.500: "5G System; Technical Realization of Service Based Architecture; Stage 3".
[5]
TS 29.501: "5G System; Principles and Guidelines for Services Definition; Stage 3".
[6]
OpenAPI: "OpenAPI Specification Version 3.0.0", https://spec.openapis.org/oas/v3.0.0 .
[7]
TR 21.900: "Technical Specification Group working methods".
[8]
TS 33.501: "Security architecture and procedures for 5G system".
[9]
RFC 6749: "The OAuth 2.0 Authorization Framework".
[10]
TS 29.510: "5G System; Network Function Repository Services; Stage 3".
[11]
RFC 7540: "Hypertext Transfer Protocol Version 2 (HTTP/2)".
[12]
RFC 8259: "The JavaScript Object Notation (JSON) Data Interchange Format".
[13]
RFC 7807: "Problem Details for HTTP APIs".
[14]
RFC 6902: "JavaScript Object Notation (JSON) Patch".[15] 3GPP TS 29.518: "5G System; Access and Mobility Management Service; Stage 3".
[16]
TS 29.571: "5G System; Common Data Types for Service Based Interfaces Stage 3".
[17]
TS 29.510: "5G System; Network Function Repository Services; Stage 3".
3 Definitions, abbreviations p. 9
3.1 Definitions p. 9
For the purposes of the present document, the terms and definitions given in TR 21.905 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in TR 21.905.
3.2 Abbreviations p. 9
For the purposes of the present document, the abbreviations given in TR 21.905 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in TR 21.905.
5GC
5G Core Network
AF
Application Function
AMF
Access Management Function
EAC
Early Admission Control
MCX
Mission Critical Service
MPS
Multimedia Priority Service
NEF
Network Exposure Function
NSAC
Network Slice Admission Control
NSACF
Network Slice Admission Control Function
SMF
Session Management Function
4 Overview p. 9
4.1 General p. 9
Within the 5GC, the NSACF offers services to the AMF, SMF (or combined SMF+PGW-C), NWDAF and NEF via the Nnsacf service based interface (see TS 23.501 and TS 23.502).
Figure 4-1 provides the reference model (in service based interface representation and in reference point representation), with focus on the NSACF and the scope of the present specification.
The functionalities supported by the NSACF are listed in clause 6.2.28 of TS 23.501.
The services and service operations provided by the Nnsacf interface are listed in clause 5.2.21 of TS 23.502.
When the UE connects to EPS and EPS counting is required, it is the combined SMF+PGW-C invokes NSACF services to perform network slice admission control, during PDN connection establishment procedure and PDN connection release procedure, as specified in clause 5.15.11.5 of TS 23.501.
4.2 NSAC support in roaming p. 10
In the roaming scenario, depending on operator's policy and roaming agreement, the NSAC procedure may be performed by the VPLMN for roaming UEs (see clause 5.15.11.3 of TS 23.501).
For roaming UEs with LBO PDU session, the vNSACF offers service to the NF in the VPLMN (e.g. AMF in the VPLMN, anchor SMF in the VPLMN). The hNSACF in the HPLMN is not used in this release of the specification (see clause 4.2.4 of TS 23.501).
If the VPLMN is configured to perform NSAC procedure, for roaming UE with HR PDU session, the vNSACF offers service to the NF in VPLMN (e.g. AMF in VPLMN) while the hNSACF offers service to the NF in HPLMN (e.g. anchor SMF in the HPLMN).
If the NSAC service is only provisioned in the HPLMN and the VPLMN supports NSAC procedure towards the HPLMN for roaming UE with HR PDU session, the hNSACF offers service to both NF in VPLMN and NF in HPLMN (e.g. AMF in VPLMN, anchor SMF in HPLMN).
