ETSI TS 129 508 V18.11.0 (2026-03)

5G; 5G System; Session Management Event Exposure Service; Stage 3 (3GPP TS 29.508 version 18.11.0 Release 18)

RTS/TSGC-0329508vib0

General Information

• Status: Not Published
• Technical Committee: 3GPP CT 3 - Interworking with external networks (formely CN3)
• Current Stage: 8 - Draft receipt by ETSI Secretariat
• Completion Date: 10-Mar-2026

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
5G System;
Session Management Event Exposure Service;
Stage 3
(3GPP TS 29.508 version 18.11.0 Release 18)


3GPP TS 29.508 version 18.11.0 Release 18 1 ETSI TS 129 508 V18.11.0 (2026-03)

Reference
RTS/TSGC-0329508vib0
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5G
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ETSI
3GPP TS 29.508 version 18.11.0 Release 18 2 ETSI TS 129 508 V18.11.0 (2026-03)
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ETSI
3GPP TS 29.508 version 18.11.0 Release 18 3 ETSI TS 129 508 V18.11.0 (2026-03)
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 . 8
4.1 Service Description . 8
4.1.1 Overview . 8
4.1.2 Service Architecture . 9
4.1.3 Network Functions . 10
4.1.3.1 Session Management Function (SMF) . 10
4.1.3.2 NF Service Consumers . 10
4.2 Service Operations . 11
4.2.1 Introduction. 11
4.2.2 Nsmf_EventExposure_Notify Service Operation . 11
4.2.2.1 General . 11
4.2.2.2 Notification about subscribed events . 11
4.2.3 Nsmf_EventExposure_Subscribe Service Operation . 17
4.2.3.1 General . 17
4.2.3.2 Creating a new subscription . 17
4.2.3.3 Modifying an existing subscription . 20
4.2.4 Nsmf_EventExposure_UnSubscribe Service Operation . 22
4.2.4.1 General . 22
4.2.4.2 Unsubscription from event notifications . 22
4.2.5 Nsmf_EventExposure_AppRelocationInfo Service Operation . 23
4.2.5.1 General . 23
4.2.5.2 Acknowledgement of Notification about subscribed events . 23
5 Nsmf_EventExposure API . 24
5.1 Introduction . 24
5.2 Usage of HTTP . 24
5.2.1 General . 24
5.2.2 HTTP standard headers . 24
5.2.2.1 General . 24
5.2.2.2 Content type . 24
5.2.3 HTTP custom headers . 25
5.3 Resources . 25
5.3.1 Resource Structure . 25
5.3.2 Resource: SMF Notification Subscriptions . 25
5.3.2.1 Description . 25
5.3.2.2 Resource definition . 25
5.3.2.3 Resource Standard Methods . 26
5.3.2.3.1 POST . 26
5.3.2.4 Resource Custom Operations . 26
5.3.3 Resource: Individual SMF Notification Subscription . 26
5.3.3.1 Description . 26
5.3.3.2 Resource definition . 27
5.3.3.3 Resource Standard Methods . 27
5.3.3.3.1 GET . 27
5.3.3.3.2 PUT . 28
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5.3.3.3.3 DELETE . 29
5.3.3.4 Resource Custom Operations . 31
5.4 Custom Operations without associated resources. 31
5.5 Notifications . 31
5.5.1 General . 31
5.5.2 Event Notification . 31
5.5.2.1 Description . 31
5.5.2.2 Target URI . 31
5.5.2.3 Standard Methods . 31
5.5.2.3.1 POST . 31
5.5.3 Acknowledgement of event notification . 33
5.5.3.1 Description . 33
5.5.3.2 Target URI . 33
5.5.3.3 Standard Methods . 33
5.5.3.3.1 POST . 33
5.6 Data Model . 34
5.6.1 General . 34
5.6.2 Structured data types . 38
5.6.2.1 Introduction . 38
5.6.2.2 Type NsmfEventExposure . 39
5.6.2.3 Type NsmfEventExposureNotification . 43
5.6.2.4 Type EventSubscription . 44
5.6.2.5 Type EventNotification . 45
5.6.2.6 void. . 51
5.6.2.7 Type AckOfNotify . 51
5.6.2.8 Type SmNasFromUe . 51
5.6.2.9 Type SmNasFromSmf . 51
5.6.2.10 Type TransactionInfo . 52
5.6.2.11 Type PduSessionInformation . 52
5.6.2.12 Type PduSessionInfo . 52
5.6.2.13 Type UpfInformation . 52
5.6.2.14 Type: TrafficCorrelationNotification . 53
5.6.3 Simple data types and enumerations . 53
5.6.3.1 Introduction . 53
5.6.3.2 Simple data types . 53
5.6.3.3 Enumeration: SmfEvent . 54
5.6.3.4 Enumeration: NotificationMethod . 54
5.6.3.5 void. . 55
5.6.3.6 Enumeration: AppliedSmccType . 55
5.6.3.7 Enumeration: TransactionMetric . 55
5.6.3.8 Enumeration: PduSessionStatus . 55
5.7 Error handling . 55
5.7.1 General . 55
5.7.2 Protocol Errors . 55
5.7.3 Application Errors . 55
5.8 Feature negotiation . 56
5.9 Security . 59
Annex A (normative): OpenAPI specification . 60
A.1 General . 60
A.2 Nsmf_EventExposure API . 60
Annex B (informative): Change history . 74
History . 79

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3GPP TS 29.508 version 18.11.0 Release 18 5 ETSI TS 129 508 V18.11.0 (2026-03)
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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3GPP TS 29.508 version 18.11.0 Release 18 6 ETSI TS 129 508 V18.11.0 (2026-03)
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 9113: "HTTP/2".
[9] IETF RFC 8259: "The JavaScript Object Notation (JSON) Data Interchange Format".
[10] OpenAPI: "OpenAPI Specification Version 3.0.0", https://spec.openapis.org/oas/v3.0.0.
[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".
[18] IETF RFC 9457: "Problem Details for HTTP APIs".
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[19] 3GPP TR 21.900: "Technical Specification Group working methods".
[20] 3GPP TS 29.522: "5G System; Network Exposure Function Northbound APIs; Stage 3".
[21] 3GPP TS 23.288: "Architecture enhancements for 5G System (5GS) to support network data
analytics services".
[22] 3GPP TS 29.514: "5G System; Policy Authorization Service; Stage 3".
[23] 3GPP TS 29.244: "Interface between the Control Plane and the User Plane of EPC Nodes".
[24] 3GPP TS 29.122: "T8 reference point for Northbound APIs".
[25] 3GPP TS 29.591: "5G System; Network Exposure Function Southbound Services; Stage 3".
[26] 3GPP TS 29.564: "5G System; User Plane Function Services; Stage 3".
[27] 3GPP TS 29.554: "5G System; Background Data Transfer Policy Control Service; Stage 3".
[28] 3GPP TS 29.519: "5G System; Usage of the Unified Data Repository service for Policy Control
Data, Application Data and Structured Data for Exposure; Stage 3".
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
DCCF Data Collection Coordination Function
DDD Downlink Data Delivery
DNAI DN Access Identifier
DNN Data Network Name
EAS Edge Application Server
FQDN Fully Qualified Domain Name
GPSI Generic Public Subscription Identifier
GUAMI Globally Unique AMF Identifier
HTTP Hypertext Transfer Protocol
H-SMF Home SMF
I-SMF Intermediate SMF
JSON JavaScript Object Notation
NEF Network Exposure Function
NF Network Function
NID Network Identifier
NRF Network Repository Function
NSSAI Network Slice Selection Assistance Information
NWDAF Network Data Analytics Function
PCF Policy Control Function
PRA Presence Reporting Area
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QFI QoS Flow Identifier
SMCC Session Management Congestion Control
SMCCE Session Management Congestion Control Experience
SMF Session Management Function
SNPN Stand-alone Non-Public Network
SUPI Subscription Permanent Identifier
S-NSSAI Single Network Slice Selection Assistance Information
SSC Session and Service Continuity
UDM Unified Data Management
UPF User Plane Function
V-SMF Visited SMF
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 NF service consumers to subscribe and unsubscribe for events on a PDU session; and
- notifies recipient of notification(s) subscribed by NF service consumers with a corresponding subscription about
observed events on the PDU session.
The types of observed events applicable for (H-)SMF (i.e. in non-roaming and LBO scenarios) include:
- UP path change (e.g. addition and/or removal of PDU session anchor);
- access type change;
- RAT type change;
- PLMN change;
- PDU session release;
- PDU session establishment;
- Downlink data delivery status;
- UE IP address/prefix change;
- QFI allocation;
- QoS monitoring;
- SM congestion control experience for PDU Session;
- Dispersion;
- Satellite backhaul category change;
- WLAN information for PDU Session;
- Redundant transmission experience for PDU Session;
- UPF events; and/or
- Traffic Correlation.
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The types of observed events applicable for V-SMF include:
- Downlink data delivery status;
- UP Path Change (for the HR-SBO scenario).
The types of observed events applicable for I-SMF include:
- Downlink data delivery status;
- UPF events.
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).
The known NF service consumers of the Nsmf_EventExposure service are:
- Network Exposure Function (NEF),
- Access and Mobility Management Function (AMF),
- Application Function (AF),
- Unified Data Management (UDM),
- Network Data Analytics Function (NWDAF), and
- Data Collection Coordination Function (DCCF).
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 or NEF to the UP_PATH_CH,
TRAFFIC_CORRELATION event and/or the QOS_MON event by including the information on AF or
NEF 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 NWDAF DCCF
UDM
Function
Figure 4.1.2-1: Reference Architecture for the Nsmf_EventExposure Service; SBI representation
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SMF
N11
N29
N10
AF UDM NWDAF DCCF
AMF NEF
Figure 4.1.2-2: Reference Architecture for the Nsmf_EventExposure Service: reference point
representation
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 means to securely expose the services and capabilities provided by 3GPP network functions to e.g. 3rd
parties or internal exposure consumer NF.
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.
The Unified Data Management (UDM).
- has access to subscriber information, can determine the SMF serving a user based on that data, and can then
subscribe to event notifications for a user (e.g. when triggered by the NEF).
The Network Data Analytics Function (NWDAF)
- collects data based on event subscription provided by AMF, SMF, UPF, PCF, UDM, AF (directly or via NEF)
and OAM;
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- retrieves information about NFs;
- performs on demand provision of analytics to NF service consumers, as indicated in clause 6,
3GPP TS 23.288 [21].
The Data Collection Coordination Function (DCCF)
- coordinates the collection and distribution of data and analytics.
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 recipient (H-)SMF, V-SMF, I-
of notification(s) which the NF service consumer SMF
has subscribed to the event report service.
Subscribe This service operation is used by an NF service NF service
consumer to subscribe for event notifications on a consumers (e.g.
specified PDU session, or for all PDU Sessions of AMF, NEF, AF, UDM,
one UE, a group of UE(s) or any UE, or to modify a NWDAF, DCCF)
subscription.
UnSubscribe This service operation is used by an NF service NF service
consumer to unsubscribe from event notifications. consumers (e.g.
AMF, NEF, AF, UDM,
NWDAF, DCCF)
AppRelocationInfo This service operation is used by an NF service NF service
consumer to acknowledge the notification from the consumers (e.g. NEF,
SMF regarding UE PDU Session related event(s) AF)

NOTE: The Nsmf_TrafficCorrelation_Notify Service Operation defined in clause 5.2.8.5.2 of
3GPP TS 23.502 [3] is implemented as the "TRAFFIC_CORRELATION" event in the
Nsmf_EventExposure_Notify Service Operation with "CommonEASDNAI" feature support.
4.2.2 Nsmf_EventExposure_Notify Service Operation
4.2.2.1 General
The Nsmf_EventExposure_Notify service operation enables the SMF (i.e. (H-)SMF, V-SMF and/or I-SMF) to send
notifications to recipient of notification(s) subscribed by NF service consumers upon the occurrence of a previously
subscribed event on the related PDU session.
The following procedure using the Nsmf_EventExposure_Notify service operation is supported:
- notification about subscribed events.
4.2.2.2 Notification about subscribed events
The present "notification about subscribed events" procedure is performed by the SMF when any of the subscribed
events occur.
The following applies with respect to the detection of subscribed events:
- If:
- the SMF supports the "DownlinkDataDeliveryStatus" feature,
- the event "DDDS" is subscribed,
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- the traffic descriptors of the downlink data source have been provided for that subscription, and
- the SMF is informed that the UE corresponding to that subscription is unreachable,
- if the data is buffered at the UPF, then the SMF shall interact with the UPF to notify that the UPF buffers
the downlink packets. The SMF shall include the traffic descriptor of the subscriptions in the PDR with a
higher priority if the PCC is not applied to the PDU session or derive the PDR from the PCC rule
received from the PCF as defined in clause 4.2.4.27 of 3GPP TS 29.512 [14] if the PCC is applied to the
PDU session and request the UPF to report when there are corresponding buffered downlink packets or
discarded packets in the UPF as defined in clause 5.28.1 of 3GPP TS 29.244 [23]. When receiving the
report from the UPF, the SMF shall determine whether that subscribed event with delivery status
"DISCARDED" or "BUFFERED" occurred. The SMF shall determine that subscribed event with delivery
status "TRANSMITTED" occurred by the fact that the related PDU session becomes ACTIVE.
- if the data is buffered at the SMF, the SMF shall determine whether that subscribed event occurred by
comparing the downlink packets with the traffic descriptors received in the corresponding event
subscription. If the SMF decides to buffer the packets, the subscribed event with delivery status
"BUFFERED" occurred. If the SMF decides to discard the packets, the subscribed event with delivery
status "DISCARDED" occurred. The SMF shall determine that subscribed event with delivery status
"TRANSMITTED" occurred by the fact that the related PDU session becomes ACTIVE.
Figure 4.2.2.2-1 illustrates the notification about subscribed events.
NF service
SMF
consumer
1. POST {notifUri}
2. "204 No Content"
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, 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 and/or traffic correlation as defined in clause 4.2.6.2.6.2 of
3GPP TS 29.512 [14], or as provided by the PCF for implicit subscription of QoS Monitoring as defined in
clause 4.2.3.25 of 3GPP TS 29.512 [14], as "notifId" attribute, or as provided by the V-NEF for implicit
subscription of UP path change as defined in clause 4.4.2.4.2 of 3GPP TS 29.591 [28], as
"upPathChgNotifCorreId" attribute within "eventNotifications" 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
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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;
g) if the PDU Session type is Ethernet, the MAC address of the UE in the "ueMac" attribute;
h) if the "CommonEASDNAI" feature is supported,
- the candidate DNAI(s) for the PDU Session in "candidateDnais" attribute, optionally together with
the indication of their prioritization within the "candDnaisPrioInd" attribute, if the "candDnaiInd"
attribute was set to "true" in the PCC rule(s); or
- the indication of EAS re-discovery in "easRediscoverInd" attribute if EAS re-discovery took place.
i) if both the SMF and the NF service consumer support "ULBuffering" and/or "EASIPreplacement"
features, these supported features within the "supportedFeatures" attribute.
NOTE 1: The SMF gets the knowledge of the feature supported by the NF service consumer as described in
clause 5.8.
j) if the "EasRelocationEnh" feature is supported and the SMF determines that the target DNAI is supported
by an AF different to the one that shall receive this notification, the identifier of the target AF that
supports this DNAI in the "targetAfId" attribute.
k) if the "HR-SBO" feature is supported and the SMF determines that the UE has moved to a serving PLMN
in which local traffic offload is allowed, the identifier of this new serving PLMN within the "plmnId"
attribute, as well as the DNN and S-SNSSAI of the HPLMN within the "dnn" and "snssai" attributes,
respectively.
NOTE 2: The SMF can determine this by comparing the AF ID of the EAS Deployment Information entry that
contains the old DNAI with the AF ID of the EAS Deployment Information entry that contains the target
DNAI. These EAS Deployment Information entries are received via the Nnef_EASDeployment API
defined in 3GPP TS 29.591 [25].
NOTE 3: 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 clause 4.2.6.2.6.2 of
3GPP TS 29.512 [14]).
NOTE 4: If the DNAI is not changed while the N6 traffic routing information change, the source DNAI and target
DNAI are not provided.
NOTE 5: 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;
ETSI
3GPP TS 29.508 version 18.11.0 Release 18 14 ETSI TS 129 508 V18.11.0 (2026-03)
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;
b) DNN of the released PDU session as "dnn" attribute, if the "PduSessionStatus" feature is supported;
c) The type of the released PDU session as "pduSessType" attribute, if the "PduSessionStatus" feature is
supported;
d) UE IPv4 address as "ipv4Addr" attribute and/or IPv6 information (IPv6 prefix(es) or IPv6 address(es)) as
"ipv6Prefixes" or "ipv6Addrs" attributes, if the released PDU session type is IP and the
"PduSessionStatus" feature is supported; and
e) S-NSSAI of the released PDU session as "snssai" attribute, if the "EneNA" feature is supported and
"snssai" attribute
...