ETSI TS 128 535 V18.2.0 (2024-10)

LTE; 5G; Management and orchestration; Management services for communication service assurance; Requirements (3GPP TS 28.535 version 18.2.0 Release 18)

RTS/TSGS-0528535vi20

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 5 - Telecom Management
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 10-Oct-2024

Standards Content (Sample)

TECHNICAL SPECIFICATION
LTE;
5G;
Management and orchestration;
Management services for communication service assurance;
Requirements
(3GPP TS 28.535 version 18.2.0 Release 18)

3GPP TS 28.535 version 18.2.0 Release 18 1 ETSI TS 128 535 V18.2.0 (2024-10)

Reference
RTS/TSGS-0528535vi20
Keywords
5G,LTE
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3GPP TS 28.535 version 18.2.0 Release 18 2 ETSI TS 128 535 V18.2.0 (2024-10)
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Legal Notice
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Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
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Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 4
Introduction . 5
1 Scope . 6
2 References . 6
3 Definitions of terms, symbols and abbreviations . 6
3.1 Terms . 6
3.2 Symbols . 7
3.3 Abbreviations . 7
4 Concepts and background . 7
4.1 Void . 7
4.2 Management control loops . 7
4.2.1 Overview . 7
4.2.2 Control loops . 8
4.2.3 Open control loops . 9
4.2.4 Closed control loops . 9
4.2.4.1 Description . 9
4.2.4.2 Lifecycle phases . 10
4.2.5 Closed control loop governance and monitoring . 11
4.2.5.1 Overview . 11
4.2.5.2 Closed control loop governance . 11
4.2.5.3 Closed control loop monitoring. 12
4.2.6 Coordination between closed control loops . 12
4.3 Communication service assurance service . 12
5 Business level use cases and requirements . 14
5.1 Use cases . 14
5.1.1 Communication service assurance . 14
5.1.2 Communication service assurance for shared resources . 14
5.1.3 Use case for obtaining resource requirements for a communication service . 15
5.1.4 Use case for interaction with core network for service assurance . 15
6 Specification level use cases and requirements . 16
6.1 Use cases . 16
6.1.1 Communication service quality assurance and optimization . 16
6.1.2 NWDAF assisted communication service SLS Assurance . 16
6.1.3 5G Core assisted SLS communication service Assurance . 17
6.1.4 Communication service SLS assurance control . 17
6.1.5 Network prediction assisted SLS communication service Assurance . 17
6.1.6 Limiting the actions of an assurance closed loop. 18
6.1.7 Trigger based Assurance Closed Control Loop (ACCL) state change . 18
6.1.8 Assurance closed loop execution supervision . 19
6.1.9 Targeted Assurance Closed Control Loop (ACCL) . 19
6.2 Requirements . 20
Annex A (informative): Change history . 22
History . 23

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Foreword
This Technical Specification has been produced by the 3rd 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.
In the present document, modal verbs have the following meanings:
shall indicates a mandatory requirement to do something
shall not indicates an interdiction (prohibition) to do something
The constructions "shall" and "shall not" are confined to the context of normative provisions, and do not appear in
Technical Reports.
The constructions "must" and "must not" are not used as substitutes for "shall" and "shall not". Their use is avoided
insofar as possible, and they are not used in a normative context except in a direct citation from an external, referenced,
non-3GPP document, or so as to maintain continuity of style when extending or modifying the provisions of such a
referenced document.
should indicates a recommendation to do something
should not indicates a recommendation not to do something
may indicates permission to do something
need not indicates permission not to do something
The construction "may not" is ambiguous and is not used in normative elements. The unambiguous constructions
"might not" or "shall not" are used instead, depending upon the meaning intended.
can indicates that something is possible
cannot indicates that something is impossible
The constructions "can" and "cannot" are not substitutes for "may" and "need not".
will indicates that something is certain or expected to happen as a result of action taken by an agency
the behaviour of which is outside the scope of the present document
will not indicates that something is certain or expected not to happen as a result of action taken by an
agency the behaviour of which is outside the scope of the present document
might indicates a likelihood that something will happen as a result of action taken by some agency the
behaviour of which is outside the scope of the present document
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might not indicates a likelihood that something will not happen as a result of action taken by some agency
the behaviour of which is outside the scope of the present document
In addition:
is (or any other verb in the indicative mood) indicates a statement of fact
is not (or any other negative verb in the indicative mood) indicates a statement of fact
The constructions "is" and "is not" do not indicate requirements.
Introduction
The present document describes closed control loop assurance solution enabling a service provider or an operator to
continuously deliver the requested level of communication service quality to the customer and is part of a TS-family
covering the 3rd Generation Partnership Project Technical Specification Group Services and System Aspects
Management and orchestration of networks, as identified below:
TS 28.535: Management Services for Communication Service Assurance; Requirements
TS 28.536: Management Services for Communication Service Assurance; Stage 2 and stage 3
The solution described builds upon the management services specifications as identified below:
TS 28.530: Management and orchestration; Concepts, use cases and requirements
TS 28.533: Management and orchestration; Architecture framework
TS 28.532: Management and orchestration; Generic management services
TS 28.540: Management and orchestration; 5G Network Resource Model (NRM); Stage 1
TS 28.541: Management and orchestration; 5G Network Resource Model (NRM); Stage 2 and stage 3
TS 28.531: Management and orchestration; Provisioning
TS 28.111: Management and orchestration; Fault Management (FM)
TS 28.550: Management and orchestration; Performance assurance
TS 28.552: Management and orchestration; 5G performance measurements
TS 28.554: Management and orchestration; 5G End to end Key Performance Indicators (KPI)

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1 Scope
The present document describes, concepts and background, and specifies use cases and requirements for closed control
loop communication service assurance solution that adjusts and optimizes the services provided by NG-RAN and 5GC.
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 22.261: "Service requirements for the 5G system".
[3] 3GPP TS 28.550: "Management and orchestration; Performance assurance".
[4] 3GPP TS 28.531: "Management and orchestration; Provisioning".
[5] ETSI GS ZSM 002 (V1.1.1) (2019-08): "Zero-touch network and Service Management (ZSM);
Reference Architecture".
[6] Void
[7] 3GPP TS 28.552: "Management and orchestration; 5G performance measurements".
[8] 3GPP TS 28.554: "Management and orchestration; 5G end to end Key Performance Indicators
(KPI)".
[9] 3GPP TS 28.532: "Management and orchestration; Generic management services".
[10] 3GPP TS 23.003: " Numbering, addressing and identification".
[11] ETSI GS ZSM 009-1 (V1.1.1) (2021-06): "Zero-touch network and Service Management (ZSM);
Closed-Loop Automation; Part 1: Enablers".
[12] 3GPP TS 28.111: "Fault management".

3 Definitions of terms, symbols and abbreviations
3.1 Terms
For the purposes of the present document, the terms given in 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 TR 21.905 [1].
communication services: subset of 3GPP defined services. Examples of 3GPP services (e.g. 5G LAN, URLLC) can be
found in TS 22.261 [2].
service level specification: specification of the minimum acceptable standard of service.
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SLA requirements: service and network requirements derived from SLAs.
NOTE: A provider can add additional requirements not directly derived from SLA's, associated to provider
internal [business] goals.
3.2 Symbols
Void.
3.3 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].
CN Core Network
CS Communication Service
CSA Communication Service Assurance
CSC Communication Service Customer
CSP Communication Service Provider
eMBB enhanced Mobile BroadBand
KPI Key Performance Indicator
MDAS Management Data Analytics Service
MnS Management Service
NF Network Function
NSI NetworkSlice Instance
NSSI NetworkSlice Subnet Instance
NSP NetworkSlice Provider
NWDAF Network Data Analytics Function
QoE Quality of Experience
SD Slice Differentiator
SLA Service Level agreement
SLS Service Level Specification
S-NSSAI Single Network Slice Selection Assistance Information
SST Slice/ServiceType
4 Concepts and background
4.1 Void
4.2 Management control loops
4.2.1 Overview
For communication service assurance one can identify two interactions of management control loops:
1) Between the CSC and the CSP: In this case, the CSC provides the requirements for an assured communication
service to the CSP, the CSP provides the corresponding communication service, the CSP also provides feedback
to the CSC. The CSP adjusts the resources used by a communication service or the CSC adjusts the SLS
continuously to achieve the assured requirements.
2) Between the CSP and the NSP: the communication service provided by CSP requires the network capabilities.
For example, the CSP requires a certain network latency. The NSP management system adjusts the network or
CSP adjusts the latency requirement continuously to satisfy the latency requirement.
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Figure 4.2.1.1: Communication service closed control loop assurance
Figure 4.2.1.1 gives a high level description of interaction process involved in the management closed control loop.
Generally, the management control loop for CSA consists of the steps Monitoring, Analysis, Decision and Execution.
The adjustment of the resources used for the communication service is completed by the continuous iteration of the
steps in a management control loop. As described in clause 4.2.4.2, the management closed control loop for the
resources used for the communication service is deployed in the preparation phase and takes effect during the
preparation phase and operation phase.
Figure 4.2.1.2 shows the overall process of communication service assurance using a management control loop.

Figure 4.2.1.2: Management Control Loop
4.2.2 Control loops
A control loop is a building block for management of networks and services. The basic principle of any control loop is
to make adjustments to let the value of a measured or observed variable (expressed as for example an attribute) be equal
to the value of a desired goal (expressed as for example an attribute). The producer of the measurements or
observations, the control service, and the controlled entity are all required to create a control loop.
For the control loop to act on input in the context of the set goal, the control loop provided through following four steps
that continuously consume and produce information from each other in a loop in the following sequence monitor,
analyse, decide and execute.
A control loop can be an open control loop in which case a human operator or other management entity intervenes
inside the loop. A control loop can be closed and operates without human operator or other management entity
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involvement inside the loop other than possibly the initial configuration of the measurement producer and configuration
of control loop.
4.2.3 Open control loops
In an open control loop, the human operator or other management entity intervenes in one or more of the process steps
inside the loop, see Figure 4.2.3.1. The human operator or other management entity is in control of the steps in the
control loop, including decisions taken in the loop. The management system collects, analyses and presents the data to
the human operator or other management entity, but the human operator or other management entity decides which
action to take. In this case, the completion time for control loop is dependent on availability and reaction time of a
human operator or other management entity.

Figure 4.2.3.1: Open control loop entities
4.2.4 Closed control loops
4.2.4.1 Description
In a closed control loop, there is no direct involvement of a human operator or other management entity in the control
loop, the control loop is fully automated. As shown in Figure 4.2.4.1.1 the human operator or management entity is not
directly controlling the details inside the process steps but provides control outside the loop. For example, configuring
goals for the control loop to make autonomous decisions within the boundaries of the set goal. Once the control loop is
configured with the goal, the controlled entity is adjusted according to the set goals.
In a closed control loop the input to the control loop provided by human operator or other management entity may
include the goal or policies. The output of the closed control loop may include closed control loop status to a human
operator or other management entity.
Typically, the goal is set within certain parameter boundaries, the closed control loop can automatically adjust the
output based on the input within the parameter boundaries. Once a control loop cannot automatically adjust, the human
operator or other management entity needs to be informed. The human operator or other management entity may decide
to change the management of closed control loop so that it becomes an open control loop, where decisions are made by
the human operator or other management entity and not by the closed control loop.
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Figure 4.2.4.1.1: Closed control loop entities
4.2.4.2 Lifecycle phases
Communication service assurance is enabled by closed control loops which have their own lifecycle. The lifecycle
phases for closed control loops are preparation, commissioning, operation and decommissioning.
- Preparation phase:
Providing a closed control loop starts with preparation, which includes control loop design, collection of relevant
goal information from an SLS and preparing the required network configuration for measurement collection.
The result of the preparation phase is a closed control loop design.
- Commissioning phase:
Once a closed control loop is prepared, one instance of the closed control loop design is instantiated by
configuring the measurement collection and the goals in the network. During this phase the closed control
loop may be deployed to allow the network to converge to a state where the communication service
assurance is stable and within the boundaries of the SLS. The instantiation activity results in a closed control
loop that is ready for operation.
- Operation phase:
After the commissioning phase, the closed control loop is operational. The activation includes actions that make
a closed control loop run to pursuit its goal(s). It may include subscription to relevant management services.
In the operation phase the closed control loop is first activated. The monitor activity typically includes the
real-time or periodic calculation of KPIs that are relevant to the closed control loop and comparison with the
goal(s) assigned to the given closed control loop. This activity may result in further actions that involve the
other activities in the operation phase, e.g. evaluate and update, in order to change the closed control loop
settings and improve its performance. The update of the closed control loops may be triggered by the (re-
)configuration of goals from the consumer. The evaluate activity also includes the evaluation of results of
Execution step of closed control loops by e.g. investigating differences between the current traffic data and
the data taken before the execution. The criteria of this evaluation can be done by specific values such as
SLS. The update & upgrade activity includes actions that change the settings of the closed control loop
instance to change its behaviour and improve its performance to pursue the assigned goal(s). The update may
include changes in the parameters of the management functions that constitute the closed control loop (e.g.
changing data sources, KPIs being calculated, models, policies, etc.). The upgrade may include changes in
the software version of the management functions. These activities can be executed dynamically while the
closed control loop is regularly operating and executing actions, or they can be executed upon a request
received from an authorized consumer. The deactivation activity includes actions that make the closed
control loop stop to run.
- Decommissioning phase:
When the closed control loop is no longer needed, after being deactivated the closed control loop is
decommissioned and after that the lifecycle of the closed control loop is completed.
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Figure 4.2.4.2.1 highlights the lifecycle phase sequence involved in the closed control loop assurance.

Decommissioning
Commissioning Operation
Preparation
Figure 4.2.4.2.1: Lifecycle phases of a closed control loop

4.2.5 Closed control loop governance and monitoring
4.2.5.1 Overview
The closed control loop can be viewed as an entity to be managed, which means the implementation of the internal
capabilities and internal interactions between the steps could not be externally visible. However, some management
capabilities (e.g. closed control loop governance and closed control loop monitoring) will exposed by the MnS
producer, implementing the closed control loops, to enable the MnS consumer to manage the closed control loops.

Figure 4.2.5.1 Closed control loop governance and monitoring
4.2.5.2 Closed control loop governance
Closed control loop governance describes a set of capabilities to allow MnS consumer to govern closed control loop,
including:
- Lifecycle management of closed control loop, including create, modify,activate/deactivate,delete closed control
loop.
- Configure goals for closed control loop.
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4.2.5.3 Closed control loop monitoring
Closed control loop monitoring describes a set of capabilities to allow MnS consumer to monitoring the progress and
result of closed control loop, including:
Monitor the goal fulfillment of the closed control loop.
4.2.6 Coordination between closed control loops
Different closed control loops reside in the management domains or in the network functions to support automation and
the autonomous networks. Different domains may involve overlapping or nonoverlapping coverage areas. The purposes
and results of a closed control loop may have impacts on other closed control loops. Coordination between closed
control loops is needed for example in and between, the Cross Management Domain and 5GC management domain or
the NG-RAN management domain, to improve the performance in order to achieve the goal(s) of the closed control
loops. Furthermore, coordination may also be needed when conflicts happen between closed control loops related to
their activities.
A closed control loop may coordinate with other closed control loops in the same domain or in a different domain.
Closed control loops in domain management for 5GC and NG-RAN are responsible for local optimization. Closed
control loops in cross management domain may need to coordinate with closed control loops in multiple other
management domains for the end to end optimization.
The relationships between closed control loops can be hierarchical and/or peer-to-peer. Coordination in the management
domains include the following categories:
- Coordination between Cross Management Domain and the 5GC Management Domain
- Coordination between Cross Management Domain and the NG-RAN Management Domain
- Coordination within Cross Management Domain, 5GC Management Domain or NG-RAN Management Domain
- Coordination within:
- Cross Management Domain,
- 5GC Management Domain and
- NG-RAN Management Domain
Coordination in management domains provides the SLS assurance from the overall management perspective. The
closed control loop in the Cross Management Domain provides governance and goals for the closed control loops in the
5GC Management Domain and the NG-RAN Management Domain. The closed control loop in the 5GC management
domain provides governance and goals for the 5GC NFs. The closed control loop in the NG-RAN management domain
provides governance and goals for the gNBs. The configuration of goals for a closed control loop may be decided
according to its goal fulfilment status and the goal decomposition from a higher level closed control loop.
Closed Loop Coordination (CLC) of Hierarchical and peer-to-peer interactions are described in ETSI GS ZSM 009-1
[11].
4.3 Communication service assurance service
Communication service assurance relies on a set of management services that together provide the CSP with the
capability to assure the communication service as per agreement (for example an SLS) with a CSC (e.g. enterprise). The
overall solution and information flows between management services and the closed control loop steps described in
Annex C of ETSI GS ZSM 002 [5] are shown in Figure 4.3.1.
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Figure 4.3.1: Overview of closed control loop information flows
In Figure 4.3.1 the controlled entity represents the resources used by a communication service and the assurance of this
communication service is provided by the closed control loop between the different management services provided by
the management system.
The input to the closed control loop is the data concerning the resources used by the communication service and
corrresponding service KPIs which is monitored by the closed control loop and step "Monitor", analyzed by the closed
control loop step “Analyze”, a decision on potential solution by the closed control loop step "Decide" which may be a
possible action for the closed control loop step "Execute", The role of the decision support services is to provide
variable degrees of automated decision making and human oversight support. The following two examples demonstrate
how a closed control loop can be used:
- when a service experience degradation is detected (for example due to resource shortage or faults in the network),
the resources used by a communication service may be adjusted automatically to improve the service experience
- the data associated with the communication service is monitored by the management services for data collection,
this management service provides information to an assurance root cause analysis management service (example
of an analytics service) and based on that information the assurance root cause analysis takes place, followed by
proposing activities, mitigation or suggestions to solve the problem. The proposed activities, for example
mitigation or problem-solving suggestion(s) are executed through provisioning services to bring the behaviour of
the communication service within the requested boundaries of the metrics (SLS goals) that are controlled by the
closed control loop.
The management services available for the closed control loop steps for "Monitor", "Analyze" and "Decide" are based
on file transfer described in TS 28.550 [3], or data streaming described in TS 28.550 [3] and notifications described in
TS 28.111 [12].
The information provided from the "Monitor" step to the "Analyze" step includes performance measurements (see TS
28.552 [7]), KPIs (see TS 28.554 [8]), performance threshold monitoring events and fault supervision events (see TS
28.532 [9]).
The insights provided from the "Analyze" step to the "Decide" step includes analytics outcomes that are not specified in
the present document.
The decision support services provided from the "Decide" step to the "Execute" step are not specified in the present
document.
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5 Business level use cases and requirements
5.1 Use cases
5.1.1 Communication service assurance
The CSP needs to meet the CSC expectations on automation as well as internal goals on CAPEX and OPEX efficiency.
The CSP has access to capabilities, procedures and tools that can address both CAPEX and OPEX in the provisioning
and management of communication services to their customers (CSC). The CSC expects the CSP to offer a variety of
communication services including business critical communication services that allow the CSC (e.g. Enterprise) to run
their applications in a predictable manner TS 22.261 [2]. Hence automation of the onboarding of the CSC application,
which will use communication services provided by the CSP, on a 5GS, is a requirement to meet the following needs:
- reduce the complexity for a CSC application to be on-boarded on a 5GS,
- improve the network performance over time, based on predicting communication service behaviour,
- assure the target goals for a CSC, and
- reduce the cost ownership through automation.
During the operation of the communication service the CSP provides assurance of service quality requirements and CSP
meets the CSC expectations on automation as well as internal goals on CAPEX and OPEX efficiency.
REQ-CSA_NSA-FUN-01 The 3GPP management system shall have capabilities to receive communication service
requirements from its authorized consumers.
REQ-CSA_NSA-FUN-02 The 3GPP management system shall have capabilities to monitor, and report to its
authorized consumers the degree of fulfilment of committed communication service requirements of authorized
consumers.
REQ-CSA_NSA-FUN-03 The 3GPP management system shall have capabilities to take actions to adjust the 5GS in
order to meet the communication service requirements of authorized consumers.
REQ-CSA_NSA-FUN-04 The 3GPP management system shall have capabilities to act to fulfil the service quality
requirements of authorized consumers.

5.1.2 Communication service assurance for shared resources
In this scenario, it is assumed that the SLA's for the two communication services will allow for them to share resources,
for example RAN resources.
The management systems CS-Assurance service receives the request from Order Care and using a MDAS CS
preparation assistance service, explores and evaluates communication service realisation and impact on other
communication services, if any.
Once the Order Care has committed to an SLA with a CSC, the management system activates the communication
service.
As the communication service operates, a management service for communication service assurance, CSA,
continuously monitors the SLA fulfilment using MDAS, PM assurance services TS 28.550 [3] including and core
network NWDAF QoE analytics service, if available.
Based on goals for SLA fulfilment, or other KPIs, the CSA service may initiate an action when SLA goals are not met,
be that over- or under fulfilment. The CSA service may use an MDAS to assist in selecting proper action and how to
best execute the action.
The CSA service triggers the action by using provisioning service TS 28.531 [4] towards RAN, transport and core
network and monitors the effect of the change.
ETSI
3GPP TS 28.535 version 18.2.0 Release 18 15 ETSI TS 128 535 V18.2.0 (2024-10)
REQ-CSIA_CON-01: The 3GPP management system shall have the capability providing a management service for
assisting in assessing (evaluating) a target SLA for a requested communication service.
REQ-CSIA_CON-02: The 3GPP management system shall have the capability providing a management service for
assisting in asserting an agreed SLA for a requested communication service.

5.1.3 Use case for obtaining resource requirements for a communication
service
Once a request for a communication service is received, the 3GPP management system needs to identify the network
resources to be used by this service in order to do service assurance. For example, during the feasibility study, in order
to assure the performance, the 3GPP management system should be able to determine the network availability for that
service. This could be done by informing the MDAS provider about the network requirements and check if the
requirements can be met with the available network resources.
MDAS provider may already have network requirement for a given service requirement, which is obtained by the
historical analysis using offline or online monitoring of network resource usage of similar services. The 3GPP
management system may check the feasibility of provisioning the communication services by using the existing
network, and if feasible, provision the communication services using that network to go to the operational phase If the
network requirement cannot be determined (e.g. not sufficient prior data), the 3GPP management system may assign
certain amount of the initial network resources and limit the number of users admitted by configuring the appropriate
CN functions. The resource usage information and the services using those resources in a given time period with their
performance (e.g. delay) is monitored by the 3GPP management system for different number of UEs to learn the
network resource requirement for different service requirements. This data could be used to determine network
requirements for future service requests during the provisioning phase or to adjust network resources to reflect the
changing service demands for the already admitted communication services.
It may be a continuous learning process in the run-time phase since service degradation could happen due to various
reasons and network resources may need to be adjusted to address such situations.
REQ-CSA_RR-CON-01 The 3GPP management system shall be able to determine the network resource requirement
for a given communication service requirement.
REQ-CSA_RR-CON-02 The 3GPP management system shall be able to allocate certain amount of network resources
for a communication service and configure the 5GC functions to limit the number of users of a given communication
service.
5.1.4 Use case for interaction with core network for service assurance
The goal is to enable the 3GPP management system to take early action to prevent service degradation.
The 3GPP management system configures the control plane functions (e.g. NWDAF) so as to report potential service
degradation according to the SLS. Service load can be determined by considering both NF(s) load in 5GC and network
utilization in access network. If the service degradation occurs or is predicted when the network capacity is decreased,
network capacity could be increased to solve the issue. Therefore, it is necessary for the 3GPP management system to
configure the 5GC functions
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