ETSI TS 129 508 V15.6.0 (2020-01)

TECHNICAL SPECIFICATION
5G;
5G System;
Session Management Event Exposure Service;
Stage 3
(3GPP TS 29.508 version 15.6.0 Release 15)


3GPP TS 29.508 version 15.6.0 Release 15 1 ETSI TS 129 508 V15.6.0 (2020-01)

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RTS/TSGC-0329508vf60
Keywords
5G
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3GPP TS 29.508 version 15.6.0 Release 15 2 ETSI TS 129 508 V15.6.0 (2020-01)
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3GPP TS 29.508 version 15.6.0 Release 15 3 ETSI TS 129 508 V15.6.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 5
1 Scope . 6
2 References . 6
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 7
4 Session Management Event Exposure Service . 7
4.1 Service Description . 7
4.1.1 Overview . 7
4.1.2 Service Architecture . 8
4.1.3 Network Functions . 9
4.1.3.1 Session Management Function (SMF) . 9
4.1.3.2 NF Service Consumers . 9
4.2 Service Operations . 9
4.2.1 Introduction. 9
4.2.2 Nsmf_EventExposure_Notify Service Operation . 9
4.2.2.1 General . 9
4.2.2.2 Notification about subscribed events . 10
4.2.3 Nsmf_EventExposure_Subscribe Service Operation . 12
4.2.3.1 General . 12
4.2.3.2 Creating a new subscription . 12
4.2.3.3 Modifying an existing subscription . 13
4.2.4 Nsmf_EventExposure_UnSubscribe Service Operation . 14
4.2.4.1 General . 14
4.2.4.2 Unsubscription from event notifications . 14
5 Nsmf_EventExposure API . 15
5.1 Introduction . 15
5.2 Usage of HTTP . 15
5.2.1 General . 15
5.2.2 HTTP standard headers . 16
5.2.2.1 General . 16
5.2.2.2 Content type . 16
5.2.3 HTTP custom headers . 16
5.3 Resources . 16
5.3.1 Resource Structure . 16
5.3.2 Resource: SMF Notification Subscriptions . 17
5.3.2.1 Description . 17
5.3.2.2 Resource definition . 17
5.3.2.3 Resource Standard Methods . 17
5.3.2.3.1 POST . 17
5.3.2.4 Resource Custom Operations . 17
5.3.3 Resource: Individual SMF Notification Subscription . 17
5.3.3.1 Description . 17
5.3.3.2 Resource definition . 18
5.3.3.3 Resource Standard Methods . 18
5.3.3.3.1 GET . 18
5.3.3.3.2 PUT . 18
5.3.3.3.3 DELETE . 19
5.3.3.4 Resource Custom Operations . 19
5.4 Custom Operations without associated resources. 19
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5.5 Notifications . 20
5.5.1 General . 20
5.5.2 Event Notification . 20
5.5.2.1 Description . 20
5.5.2.2 Target URI . 20
5.5.2.3 Standard Methods . 20
5.5.2.3.1 POST . 20
5.6 Data Model . 21
5.6.1 General . 21
5.6.2 Structured data types . 21
5.6.2.1 Introduction . 21
5.6.2.2 Type NsmfEventExposure . 22
5.6.2.3 Type NsmfEventExposureNotification . 24
5.6.2.4 Type EventSubscription . 24
5.6.2.5 Type EventNotification . 25
5.6.3 Simple data types and enumerations . 27
5.6.3.1 Introduction . 27
5.6.3.2 Simple data types . 27
5.6.3.3 Enumeration: SmfEvent . 27
5.6.3.4 Enumeration: NotificationMethod . 27
5.7 Error handling . 28
5.7.1 General . 28
5.7.2 Protocol Errors . 28
5.7.3 Application Errors . 28
5.8 Feature negotiation . 28
5.9 Security . 28
Annex A (normative): OpenAPI specification . 29
A.1 General . 29
A.2 Nsmf_EventExposure API . 29
Annex B (informative): Change history . 35
History . 36

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Foreword
rd
This Technical Specification has been produced by the 3 Generation Partnership Project (3GPP).
The contents of the present document are subject to continuing work within the TSG and may change following formal
TSG approval. Should the TSG modify the contents of the present document, it will be re-released by the TSG with an
identifying change of release date and an increase in version number as follows:
Version x.y.z
where:
x the first digit:
1 presented to TSG for information;
2 presented to TSG for approval;
3 or greater indicates TSG approved document under change control.
y the second digit is incremented for all changes of substance, i.e. technical enhancements, corrections,
updates, etc.
z the third digit is incremented when editorial only changes have been incorporated in the document.
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1 Scope
The present specification provides the stage 3 definition of the Session Management Event Exposure Service
(Nsmf_EventExposure) of the 5G System.
The stage 2 definition and procedures of the Session Management Event Exposure Service are contained in
3GPP TS 23.502 [3] and 3GPP TS 23.503 [6]. The 5G System Architecture is defined in 3GPP TS 23.501 [2].
Stage 3 call flows for policy and charging control use cases are provided in 3GPP TS 29.513 [7].
The Technical Realization of the Service Based Architecture and the Principles and Guidelines for Services Definition
of the 5G System are specified in 3GPP TS 29.500 [4] and 3GPP TS 29.501 [5].
The Session Management Event Exposure Service is provided by the Session Management Function (SMF). This
service exposes events related to PDU Sessions observed at the SMF.
2 References
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] 3GPP TR 21.905: "Vocabulary for 3GPP Specifications".
[2] 3GPP TS 23.501: "System Architecture for the 5G System; Stage 2".
[3] 3GPP TS 23.502: "Procedures for the 5G System; Stage 2".
[4] 3GPP TS 29.500: "5G System; Technical Realization of Service Based Architecture; Stage 3".
[5] 3GPP TS 29.501: "5G System; Principles and Guidelines for Services Definition; Stage 3".
[6] 3GPP TS 23.503: "Policy and Charging Control Framework for the 5G System; Stage 2".
[7] 3GPP TS 29.513: "5G System; Policy and Charging Control signalling flows and QoS parameter
mapping; Stage 3".
[8] IETF RFC 7540: "Hypertext Transfer Protocol Version 2 (HTTP/2)".
[9] IETF RFC 8259: "The JavaScript Object Notation (JSON) Data Interchange Format".
[10] OpenAPI, "OpenAPI 3.0.0 Specification", https://github.com/OAI/OpenAPI-
Specification/blob/master/versions/3.0.0.md.
[11] 3GPP TS 29.571: "5G System; Common Data Types for Service Based Interfaces Stage 3".
[12] 3GPP TS 29.510: "5G System; Network Function Repository Services; Stage 3".
[13] 3GPP TS 29.518: "5G System; Access and Mobility Management Services; Stage 3".
[14] 3GPP TS 29.512: "5G System; Session Management Policy Control Service; Stage 3".
[15] 3GPP TS 33.501: "Security architecture and procedures for 5G system".
[16] IETF RFC 6749: "The OAuth 2.0 Authorization Framework".
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[18] IETF RFC 7807: "Problem Details for HTTP APIs".
[19] 3GPP TR 21.900: "Technical Specification Group working methods".
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the terms and definitions given in 3GPP TR 21.905 [1] and the following
apply. A term defined in the present document takes precedence over the definition of the same term, if any, in
3GPP TR 21.905 [1].
3.2 Abbreviations
For the purposes of the present document, the abbreviations given in 3GPP TR 21.905 [1] and the following apply. An
abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in
3GPP TR 21.905 [1].
AF Application Function
AMBR Aggregate Maximum Bit Rate
AMF Access and Mobility Management Function
API Application Programming Interface
DNAI DN Access Identifier
DNN Data Network Name
GUAMI Globally Unique AMF Identifier
HTTP Hypertext Transfer Protocol
JSON JavaScript Object Notation
NEF Network Exposure Function
NF Network Function
NRF Network Repository Function
SMF Session Management Function
SUPI Subscription Permanent Identifier
PCF Policy Control Function
PRA Presence Reporting Area
UPF User Plane Function
4 Session Management Event Exposure Service
4.1 Service Description
4.1.1 Overview
The Session Management Event Exposure Service, as defined in 3GPP TS 23.502 [3] and 3GPP TS 23.503 [6], is
provided by the Session Management Function (SMF).
This service:
- allows consumer NFs to subscribe and unsubscribe for events on a PDU session; and
- notifies consumer NFs with a corresponding subscription about observed events on the PDU session.
The types of observed events include:
- UP path change (e,g, addition and/or removal of PDU session anchor);
- access type change;
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- PLMN change;
- PDU session release; and
- UE IP address/prefix change.
4.1.2 Service Architecture
The 5G System Architecture is defined in 3GPP TS 23.501 [2]. The Policy and Charging related 5G architecture is also
described in 3GPP TS 29.513 [7].
The Session Management Event Exposure Service (Nsmf_EventExposure) is part of the Nsmf service-based interface
exhibited by the Session Management Function (SMF),
Known consumer of the Nsmf_EventExposure service are:
- Network Exposure Function (NEF)
- Access and Mobility Management Function (AMF).
- Application Function (AF)
The PCF accesses the Session Management Event Exposure Service at the SMF via the N7 Reference point.
NOTE: The PCF can implicitly subscribe on behalf of the AF and NEF to the UP_PATH_CH event by including
the information on AF subscription within the PCC rule.
The AMF accesses the Session Management Event Exposure Service at the SMF via the N11 Reference point.
SMF
Nsmf
Nsmf_EventExposure
Application
AMF NEF
PCF
Function
Figure 4.1.2-1: Reference Architecture for the Nsmf_EventExposure Service; SBI representation
SMF
N11 N29
AMF NEF
AF
Figure 4.1.2-2: Reference Architecture for the Nsmf_EventExposure Service: reference point
representation
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4.1.3 Network Functions
4.1.3.1 Session Management Function (SMF)
The Session Management function (SMF) provides:
- Session Management e.g. Session establishment, modification and release;
- UE IP address allocation & management;
- Selection and control of UP function;
- Termination of interfaces towards Policy control functions; and
- Control part of policy enforcement and QoS.
4.1.3.2 NF Service Consumers
The Network Exposure Function (NEF);
- provides a means to securely expose the services and capabilities provided by 3GPP network functions for e.g.
3rd parties or internal exposure.
The Access and Mobility Management function (AMF) provides:
- Registration management;
- Connection management;
- Reachability management; and
- Mobility Management.
The Application Function (AF)
- interacts with the 3GPP Core Network to provide services.
4.2 Service Operations
4.2.1 Introduction
Table 4.2.1-1: Operations of the Nsmf_EventExposure Service
Service operation name Description Initiated by
Notify Report UE PDU session related event(s) to the NF SMF
service consumer which has subscribed to the
event report service.
Subscribe This service operation is used by an NF service NF service consumer
consumer to subscribe for event notifications on a
specified PDU session, or for all PDU Sessions of
one UE, a group of UE(s) or any UE, or to modify a
subscription.
UnSubscribe This service operation is used by an NF service NF service consumer
consumer to unsubscribe from event notifications.

4.2.2 Nsmf_EventExposure_Notify Service Operation
4.2.2.1 General
The Nsmf_EventExposure_Notify service operation enables notification to NF service consumers that the previously
subscribed event on the related PDU session occurred.
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The following procedure using the Nsmf_EventExposure_Notify service operation is supported:
- notification about subscribed events.
4.2.2.2 Notification about subscribed events
Figure 4.2.2.2-1 illustrates the notification about subscribed events.

Figure 4.2.2.2-1: Notification about subscribed events
If the SMF observes PDU Session related event(s) for which an NF service consumer has subscribed to, the SMF shall
send an HTTP POST request with "{notifUri}" as previously provided by the NF service consumer within the
corresponding subscription as URI and NsmfEventExposureNotification data structure as request body that shall
include:
- Notification correlation ID provided by the NF service consumer during the subscription, or as provided by the
PCF for implicit subscription of UP path change as defined in subclause 4.2.6.2.6.2 of 3GPP TS 29.512 [14], as
"notifId" attribute; and
- information about the observed event(s) within the "eventNotifs" attribute that shall contain for each observed
event an "EventNotification" data structure that shall include:
1. the Event Trigger as "event" attribute;
2. for a UP path change notification:
a) type of notification ("EARLY" or "LATE") as "dnaiChgType" attribute;
b) source DNAI and/or target DNAI as "sourceDnai" attribute and "targetDnai" attribute if DNAI is
changed, respectively (NOTE 3); and
c) if the PDU Session type is IP, for the source DNAI IP address/prefix of the UE as "sourceUeIpv4Addr"
attribute or "sourceUeIpv6Prefix" attribute; and
d) if the PDU Session type is IP, for the target DNAI IP address/prefix of the UE as "targetUeIpv4Addr"
attribute or "targetUeIpv6Prefix" attribute;
e) if available (NOTE 3), for the source DNAI, N6 traffic routing information related to the UE as
"sourceTraRouting" attribute;
f) if available (NOTE 3), for the target DNAI, N6 traffic routing information related to the UE as
"targetTraRouting" attribute; and
g) if the PDU Session type is Ethernet, the MAC address of the UE in the "ueMac" attribute;
NOTE 1: UP path change notification, i.e. DNAI change notification and/or N6 traffic routing information change
notification, can be the result of an implicit subscription of the PCF on behalf of the NEF/AF as part of
setting PCC rule(s) via the Npcf_SMPolicyControl service (see subclause 4.2.6.2.6.2 of
3GPP TS 29.512 [14]).
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NOTE 2: If the DNAI is not changed while the N6 traffic routing information change, the source DNAI and target
DNAI are not provided.
NOTE 3: The change from the UP path status where no DNAI applies to a status where a DNAI applies indicates
the activation of the related AF request and therefore only the target DNAI and N6 traffic routing
information is provided in the event notification; the change from the UP path status where a DNAI
applies to a status where no DNAI applies indicates the de-activation of the related AF request and
therefore only the source DNAI and N6 traffic routing information is provided in the event notification.
3. for a UE IP address change:
a) added new UE IP address or prefix as "adIpv4Addr" attribute or "adIpv6Prefix" attribute, respectively;
and/or
b) released UE IP address or prefix as "reIpv4Addr" attribute or "reIpv6Prefix" attribute, respectively;
4. for an access type change:
a) new access type as "accType" attribute;
5. for a PLMN Change:
a) new PLMN as "plmnId" attribute;
6. for a PDU Session Release:
a) ID of the released PDU session as "pduSeId" attribute;
7. the time at which the event was observed encoded as "timeStamp" attribute;
8. the SUPI as the "supi" attribute if the subscription applies to a group of UE(s) or any UE; and
9. if available, the GPSI as the "gpsi" attribute if the subscription applies to a group of UE(s) or any UE.
Upon the reception of the HTTP POST request with "{notifUri}" as URI and an NsmfEventExposureNotification data
structure as request body, the NF shall send an "204 No Content" HTTP response for a succesfull processing.
If the NF service consumer is not able to handle the Notification but knows by implementation specific means that
another service consumer is able to handle the notification, it shall reply with an HTTP "307 temporary redirect" error
response pointing to the new NF service consumer URI. If the NF service consumer is not able to handle the
Notification but another unknown service consumer could possibly handle the notification, it shall reply with an HTTP
"404 Not found" error response.
NOTE 4: An AMF as service consumer can change.
If the SMF receives a "307 temporary redirect" response, the SMF shall resend the failed event notification request
using the received URI in the Location header field as Notification URI. Subsequent event notifications, triggered after
the failed one, shall be sent to the Notification URI provided by the NF service consumer during the corresponding
subscription creation/update.
If the SMF becomes aware that a new NF service consumer is requiring notifications (e.g. via the "404 Not found"
response, or via Namf_Communication service AMFStatusChange Notifications, see 3GPP TS 29.518 [13], or via link
level failures or via the Nnrf_NFDiscovery Service (using the service name and GUAMI obtained during the creation of
the subscription) to query the other AMFs within the AMF set) specified in 3GPP TS 29.510 [12]), and the SMF knows
alternate or backup IPv4 or IPv6 Addess(es) where to send Notifications (e.g. via "altNotifIpv4Addrs" or
"altNotifIpv6Addrs" attributes received when the subscription was created), the SMF shall exchange the authority part
of the Notification URI with one of those addresses and shall use that URI in any subsequent communication.
If the SMF received a "404 Not found" response, the SMF should resend the failed notification to that URI.
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4.2.3 Nsmf_EventExposure_Subscribe Service Operation
4.2.3.1 General
This service operation is used by an NF service consumer to subscribe for event notifications on a specified PDU
Session, or for all PDU Sessions of one UE, group of UE(s) or any UE, or to modify an existing subscription. The
following are the types of events for which a subscription can be made:
- UP path change;
- PDU Session release;
- Change of Access Type;
- PLMN change; and
- UE IP address change.
The following procedures using the Nsmf_EventExposure_Subscribe service operation are supported:
- creating a new subscription;
- modifying an existing subscription.
4.2.3.2 Creating a new subscription
Figure 4.2.3.2-1 illustrates the creation of a subscription.
NF service
SMF
consumer
1. POST …/subscriptions/
2. "201 Created"
Figure 4.2.3.2-1: Creation of a subscription
To subscribe to event notifications, the NF service consumer shall send an HTTP POST request with: "{apiRoot}/nsmf-
event-exposure/v1/subscriptions/" as Resource URI and the NsmfEventExposure data structure as request body that
shall include:
- if the subscription applies to events related to a single PDU session, the PDU Session ID of that PDU session as
"pduSeId" attribute;
- if the subscription applies to events not related to a single PDU session, identification of UEs to which the
subscription applies via:
a) identification of a single UE by SUPI as "supi" attribute;
b) identification of a group of UE(s) via a "groupId" attribute; or
c) identification of any UE using a specific DNN via the "dnn" attribute;
NOTE: The identification of any UE does not apply for local breakout roaming scenarios where the SMF is
located in the VPLMN and the NF service consumer is located in the HPLMN.
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- an URI where to receive the requested notifications as "notifURI" attribute;
- a Notification Correlation Identifier assigned by the NF service consumer for the requested notifications as
"notifId" attribute; and
- if the NF service consumer is an AMF, the GUAMI encoded as "guami" attribute:
- a description of the subscribed events as "eventSubs" attribute that for each event shall include:
a) an event identifier as "event" attribute; and
b) for event UP path change, whether the subscription is for early, late, or early and late notifications of UP path
reconfiguration in the "dnaiChType" attribute;
The NsmfEventExposure data structure as request body may also include:
- Alternate or backup IPv4 Addess(es) where to send Notifications encoded as " altNotifIpv4Addrs" attribute;
- Alternate or backup IPv6 Addess(es) where to send Notifications encoded as " altNotifIpv6Addrs" attribute;
- if the NF service consumer is an AMF, the name of a service produced by the AMF that expects to receive the
notification about subscribed events encoded as "serviceName" attribute;
- Immediate reporting flag as "ImmeRep" attribute;
- event notification method (periodic, one time, on event detection) as "notifMethod" attribute;
- Maximum Number of Reports as "maxReportNbr" attribute;
- Monitoring Duration as "expiry" attribute; and/or
- Repetition Period for periodic reporting as "repPeriod" attribute.
Upon the reception of an HTTP POST request with: "{apiRoot}/nsmf-event-exposure/v1/subscriptions/" as Resource
URI and NsmfEventExposure data structure as request body, the SMF shall:
- create a new subscription;
- assign a subscription correlation ID;
- select an expiry time that is equal or less than a possible expiry time in the request;
- store the subscription;
- send a HTTP "201 Created" response with NsmfEventExposure data structure as response body and a Location
header field containing the URI of the created individual subscription resource, i.e. {apiRoot}/nsmf-event-
exposure/v1/subscriptions/{subId}; and
- if the "ImmeRep" attribute is included and set to true in the request, the SMF shall report the curret available
value(s) for the subscribed event(s) as defined in subclause 4.2.3.1.
If the SMF received an GUAMI, the SMF may subscribe to GUAMI changes using the AMFStatusChange service
operation of the Namf_Communication service specified in 3GPP TS 29.518 [13], and it may use the
Nnrf_NFDiscovery Service specified in 3GPP TS 29.510 [12] (using the obtained GUAMI and possibly service name)
to query the other AMFs within the AMF set.
4.2.3.3 Modifying an existing subscription
Figure 4.2.3.3-1 illustrates the modification of an existing subscription.
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Figure 4.2.3.3-1: Modification of an existing subscription
To modify an existing subscription to event notifications, the NF service consumer shall send an HTTP PUT request
with: "{apiRoot}/nsmf-event-exposure/v1/subscriptions/subId}" as Resource URI, where "{subId}" is the subscription
correlation ID of the existing subscription, and NsmfEventExposure data structure as request body as described in
subclause 4.2.3.2.
NOTE 1: An alternate NF service consumer than the one that requested the generation of the subscription resource
can send the PUT. For instance, an AMF as service consumer can change.
NOTE 2: The "notifURI" attribute within the NsmfEventExposure data structure can be modified to request that
subsequent notifications are sent to a new NF service consumer.
Upon the reception of an HTTP PUT request with: "{apiRoot}/nsmf-event-exposure/v1/subscriptions/{subId}" as
Resource URI and NsmfEventExposure data structure as request body, the SMF shall:
- store the subscription; and
- send a HTTP "200 OK" response with NsmfEventExposure data structure as response body.
4.2.4 Nsmf_EventExposure_UnSubscribe Service Operation
4.2.4.1 General
This service operation is used by an NF service consumer to unsubscribe from event notifications.
The following procedure using the Nsmf_EventExposure_UnSubscribe service operation is supported:
- unsubscription from event notifications.
4.2.4.2 Unsubscription from event notifications
Figure 4.2.4.2-1 illustrates the unsubscription from event notifications.
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Figure 4.2.4.2-1: Unsubscription from event notifications
To unsubscribe from event notifications, the NF service consumer shall send an HTTP DELETE request with:
"{apiRoot}/nsmf-event-exposure/v1/subscriptions/{subId}" as Resource URI, where "{subId}" is the subscription
correlation ID of the existing subscription that is to be deleted.
Upon the reception of the HTTP DELETE request with: "{apiRoot}/nsmf-event-exposure/v1/subscriptions/{subId}" as
Resource URI, the SMF shall:
- remove the corresponding subscription; and
- send an HTTP "204 No Content" response.
5 Nsmf_EventExposure API
5.1 Introduction
The Session Management Event Exposure Service shall use the Nsmf_EventExposure API.
The request URI used in HTTP request from the NF service consumer towards the SMF shall have the structure defined
in subclause 4.4.1 of 3GPP TS 29.501 [5], i.e.:
{apiRoot}/{apiName}/{apiVersion}/{apiSpecificResourceUriPart}
with the following components:
- The {apiRoot} shall be set as described in 3GPP TS 29.501 [5].
- The {apiName} shall be "nsmf-event-exposure".
- The {apiVersion} shall be "v1".
- The {apiSpecificResourceUriPart} shall be set as described in subclause 5.3.
5.2 Usage of HTTP
5.2.1 General
HTTP/2, IETF RFC 7540 [8], shall be used as specified in clause 5 of 3GPP TS 29.500 [4].
HTTP/2 shall be transported as specified in subclause 5.3 of 3GPP TS 29.500 [4].
The OpenAPI [10] specification of HTTP messages and content bodies for the Nsmf_EventExposure is contained in
Annex A.
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5.2.2 HTTP standard headers
5.2.2.1 General
See subclause 5.2.2 of 3GPP TS 29.500 [4] for the usage of HTTP standard headers.
5.2.2.2 Content type
JSON, IETF RFC 8259 [9], shall be used as content type of the HTTP bodies specified in the present specification as
specified in subclause 5.4 of 3GPP TS 29.500 [4]. The use of the JSON format shall be signalled by the content type
"application/json".
"Problem Details" JSON object shall be used to indicate additional details of the error in a HTTP response body and
shall be signalled by the content type "application/problem+json", as defined in IETF RFC 7807 [18].
5.2.3 HTTP custom headers
The mandatory HTTP custom header fields specified in subclause 5.2.3.2 of 3GPP TS 29.500 [4] shall be applicable.
5.3 Resources
5.3.1 Resource Structure
Figure 5.3.1-1: Resource URI structure of the Nsmf_EventExposure API
Table 5.3.1-1 provides an overview of the resources and applicable HTTP methods.
Table 5.3.1-1: Resources and methods overview
Resource HTTP method or
Resource URI Description
name custom operation
SMF {apiRoot}/ POST Create a new Individual SMF Notification
Notification nsmf-event-exposure/ Subscription resource.
Subscriptions v1/
subscriptions
Individual SMF {apiRoot}/ GET Read an Individual SMF Notification Subscription
Notification nsmf-event-exposure/ resource.
Subscription v1/ PUT Modify an existing Individual SMF Notification
subscriptions/ Subscription resource.
{subId}
DELETE Delete an Individual SMF Notification Subscription
resource and cancel the related subscription.

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5.3.2 Resource: SMF Notification Subscriptions
5.3.2.1 Description
The SMF Notification Subscriptions resource represents all subscriptions to the SMF event exposure service at a given
SMF.
5.3.2.2 Resource definition
Resource URI: {apiRoot}/nsmf-event-exposure/v1/subscriptions/
This resource shall support the resource URI variables defined in table 5.3.2.2-1.
Table 5.3.2.2-1: Resource URI variables for this resource
Name Definition
apiRoot See subclause 5.1
5.3.2.3 Resource Standard Methods
5.3.2.3.1 POST
This method shall support the URI query parameters specified in table 5.3.2.3.1-1.
Table 5.3.2.3.1-1: URI query parameters supported by the POST method on this resource
Name Data type P Cardinality Description
n/a
This method shall support the request data structures specified in table 5.3.2.3.1-2 and the response data structures and
response codes specified in table 5.3.2.3.1-3.
Table 5.3.2.3.1-2: Data structures supported by the POST Request Body on this resource
Data type P Cardinality Description
NsmfEventExposure M 1 Create a new Individual SMF Notification Subscription resource.

Table 5.3.2.3.1-3: Data structures supported by the POST Response Body on this resource
Data ty
...