ETSI GR NGP 011 V1.1.1 (2018-09)

Next Generation Protocol (NGP); E2E Network Slicing Reference Framework and Information Model

DGR/NGP-0011

General Information

• Status: Published
• Publication Date: 19-Sep-2018
• Technical Committee: NGP - Next Generation Protocols
• Current Stage: 12 - Completion
• Due Date: 05-Oct-2018
• Completion Date: 20-Sep-2018

Standards Content (Sample)

GROUP REPORT
Next Generation Protocols (NGP);
E2E Network Slicing Reference Framework and
Information Model
Disclaimer
The present document has been produced and approved by the Next Generation Protocols (NGP) ETSI Industry Specification
Group (ISG) and represents the views of those members who participated in this ISG.
It does not necessarily represent the views of the entire ETSI membership.

2 ETSI GR NGP 011 V1.1.1 (2018-09)

Reference
DGR/NGP-0011
Keywords
network, virtualisation
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3 ETSI GR NGP 011 V1.1.1 (2018-09)
Contents
Intellectual Property Rights . 5
Foreword . 5
Modal verbs terminology . 5
1 Scope . 6
2 References . 6
2.1 Normative references . 6
2.2 Informative references . 6
3 Definitions and abbreviations . 7
3.1 Definitions . 7
3.2 Abbreviations . 8
4 Network Slicing Architecture . 9
4.1 Overview . 9
4.2 Informative Background . 9
4.3 High level description . 10
4.4 Network slicing design principles . 11
4.4.1 Service Oriented Approach . 11
4.4.2 Network slice abstraction . 11
4.4.2.1 Motivation . 11
4.4.2.2 Service lifecycle abstraction. 11
4.4.2.3 Technology information abstraction . 11
4.4.2.4 Quality abstraction . 11
4.4.3 Loose coupling . 12
4.4.4 Network slice reusability . 12
4.4.5 Slice autonomy . 12
5 Information Model . 12
5.1 Reference Component Architecture . 12
5.2 Network service resource concept . 13
5.2.1 Types of resources . 13
5.2.2 Link resources . 13
5.2.3 Node resources . 13
5.3 Network slice managed objects . 13
5.3.1 General description . 13
5.3.2 Discovered objects . 14
5.3.2.1 Network slice subnet object . 14
5.3.2.2 NSP aggregated resource database . 15
5.3.3 Provisioned objects . 15
5.3.3.1 Ns service profile object . 15
5.3.4 Runtime objects . 15
5.3.4.1 NS service context object . 15
5.3.4.2 NS service operations . 16
5.3.4.3 NS subnet operations. 17
5.3.5 Network slice agent objects . 17
5.3.5.1 NS subnet resource broker . 17
5.3.5.2 NSA service segment . 18
5.3.6 NS interfaces . 18
6 High Level Functions . 18
6.1 Network slice functions . 18
6.2 Network slice subnet discovery function . 19
6.3 Network slice subnet augment function . 19
6.4 Network slice mapping function . 20
6.5 Resource computation function . 20
6.6 Network slice delegation function . 21
6.7 Report aggregation function . 21
6.8 Service assurance function . 22
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6.9 Tenant operated network service function . 22
6.9.1 Tenant operations overview . 22
6.9.2 Service endpoint attachment . 23
6.9.3 Interface to slice specific resources . 23
6.9.4 Tenant runtime OAM template . 23
7 Network Slice Enablement . 24
7.1 Mechanisms for service assurance . 24
7.1.1 Methods of assurance. 24
7.1.2 Quality of service . 24
7.1.3 Traffic Engineering relevance . 24
7.1.4 Path computation relevance . 24
7.2 Mechanisms for OAM . 25
7.3 Data path enablement . 25
7.3.1 Enabling approaches . 25
7.3.2 Existing IP based Infrastructure . 25
7.3.2.1 IP Based Modes . 25
7.3.2.2 End-to-end encapsulated mode . 26
7.3.2.3 Segmented encapsulated mode. 26
7.3.3 Next-Generation Sliced Infrastructure . 26
7.3.4 Network Slice Stitching Gateways . 26
8 Security Considerations . 27
8.1 NGMN security guidelines . 27
8.2 Protection and privacy of tenant data . 27
8.3 Tenant resource isolation . 27
8.4 Protection against impersonation attacks . 27
9 Integration Example . 28
9.1 Generic purpose service slice . 28
9.1.1 Scenario description . 28
9.1.2 Network slice bootstrap . 29
9.1.3 Network slice onboarding . 29
9.1.4 Slice operation and management . 29
Annex A: Authors & contributors . 30
Annex B: Bibliography . 31
Annex C: Change History . 32
History . 33

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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
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
server (https://ipr.etsi.org/).
Pursuant to the ETSI IPR Policy, no investigation, including IPR searches, has been carried out by ETSI. No guarantee
can be given as to the existence of other IPRs not referenced in ETSI SR 000 314 (or the updates on the ETSI Web
server) which are, or may be, or may become, essential to the present document.
Trademarks
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ETSI claims no ownership of these except for any which are indicated as being the property of ETSI, and conveys no
right to use or reproduce any trademark and/or tradename. Mention of those trademarks in the present document does
not constitute an endorsement by ETSI of products, services or organizations associated with those trademarks.
Foreword
This Group Report (GR) has been produced by ETSI Industry Specification Group (ISG) Next Generation Protocols
(NGP).
Modal verbs terminology
In the present document "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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1 Scope
The present document describes an information specification of resources used by services in network slices to provide
true resource-assured multi-tenancy across multiple administrative and technology domains. It does not, cover the data
plane or hardware aspects of traffic associated with a slice, nor does it alter the core control plane functionality of
physical network infrastructure and domains. Any specific language to describe a network slice is out of scope as well.
As such, the topic of network slices encompasses the combination of virtualization, cloud centric, NFV and SDN
technologies the primary gap identified is a lack of normalized resource information flow over a plurality of provider
administration planes (or domains). Resource requirement of a given network slice can be satisfied in different networks
using different technologies; the goal of the present document is to provide a simple manageable and operable network
through a common interface while hiding infrastructure complexities. The present document defines how several of
those technologies may be used in coordination to offer description and monitoring of services in a network slice.
Please note that the scope does not try to formally define a network slice, instead it relies on background material for
the purpose.
2 References
2.1 Normative references
Normative references are not applicable in the present document.
2.2 Informative references
References are either specific (identified by date of publication and/or edition number or version number) or
non-specific. For specific references, only the cited version applies. For non-specific references, the latest version of the
referenced document (including any amendments) applies.
NOTE: While any hyperlinks included in this clause were valid at the time of publication, ETSI cannot guarantee
their long term validity.
The following referenced documents are not necessary for the application of the present document but they assist the
user with regard to a particular subject area.
[i.1] NGMN Alliance: "5G White Paper V1.0".
NOTE: Available at
https://www.ngmn.org/fileadmin/ngmn/content/downloads/Technical/2015/NGMN_5G_White_Paper_V
1_0.pdf.
[i.2] NGMN Alliance (V1.0): "Description of Network Slicing Concept".
NOTE: Available at https://www.ngmn.org/fileadmin/user_upload/160113_Network_Slicing_v1_0.pdf.
[i.3] IETF RFC 5440: "Path Computation Element (PCE) Communication Protocol (PCEP)".
[i.4] ETSI GS NGP 001: "Next Generation Protocol (NGP); Scenario Definitions".
[i.5] IETF RFC 7665: "Service Function Chaining (SFC) Architecture".
[i.6] IANA: "Path Computation Element Protocol (PCEP) Numbers".
NOTE: Available at https://www.iana.org/assignments/pcep/pcep.xhtml.
[i.7] IETF RFC 2998: "A Framework for Integrated Services Operation over Diffserv Networks".
[i.8] IETF Traffic Engineering Architecture and Signaling (teas) Working Group.
NOTE: Available at https://datatracker.ietf.org/wg/teas/.
[i.9] NGMN White Paper on Security for Network Slicing.
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NOTE: Available at
https://www.ngmn.org/fileadmin/user_upload/160429_NGMN_5G_Security_Network_Slicing_v1_0.pdf.
[i.10] Recommendation ITU-T Y.3110/3111: "IMT-2020 network management and orchestration
requirements & framework".
[i.11] Recommendation ITU-T Y.3112: "Framework for the support of Multiple Network Slicing".
[i.12] Recommendation ITU-T Y.3150: "High-level technical characteristics of network softwarization
for IMT-2020".
[i.13] ETSI TS 123 502: "5G; Procedures for the 5G System (3GPP TS 23.502)".
[i.14] 3GPP TR 28.801: "3rd Generation Partnership Project; Technical Specification Group Services
and System Aspects: Telecom Management (SA5) - Study on management and orchestration of
network slicing/Network slice management".
[i.15] 3GPP TS 28.531: "Provisioning of network slicing for 5G networks and services: Detailed
specification of network slice provisioning/Network slice management".
[i.16] 3GPP TS 28.541: "Management and orchestration of networks and network slicing; NR and NG-
RAN Network Resource Model (NRM); Stage 2 and stage 3".
[i.17] IETF draft-netslices-usecases-02: "Network Slicing Use Cases: Network Customization and
Differentiated Services".
NOTE: Available at https://datatracker.ietf.org/doc/draft-netslices-usecases.
[i.18] draft-ietf-spring-segment-routing-14: "Segment Routing Architecture".
NOTE: Available at https://tools.ietf.org/html/draft-ietf-spring-segment-routing-14.
[i.19] IETF: "Deterministic Networking (detnet)".
NOTE: Available at https://datatracker.ietf.org/wg/detnet/.
[i.20] draft-ietf-ippm-ioam-data-02: "Data Fields for In-situ OAM".
NOTE: Available at https://tools.ietf.org/html/draft-ietf-ippm-ioam-data-02.
[i.21] BBF SD-406: "End-to-End Network Slicing".
NOTE: Available at https://wiki.broadband-forum.org/pages/viewpage.action?spaceKey=BBF&title=SD-
406+End-to-End+Network+Slicing.
[i.22] Generic Network Slice Template Version 0.1.
NOTE: Available at
https://infocentre2.gsma.com/gp/pr/FNW/NEST/WorkingDocuments/GST%20document%20baselines/G
ST_Baseline_v0.8_20180712_clean.docx
3 Definitions and abbreviations
3.1 Definitions
For the purposes of the present document, the following terms and definitions apply:
Network Slice (NS): network slice is a description of a service aware logical network that is composed of different
physical or virtual network elements, resources and functions
Network Slice Agent (NSA): entity that has complete view and control of its network infrastructure
NOTE: An agent can be a logical component of controller that performs special functions relating to network
slices and exports them to network slice provider.
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Network Slice Instance (NSI): instance of a type of network slice that has resources allocated to it from underlying
network infrastructure and is independently managed and monitored by the tenant
Network Slice Provider (NSP): entity that provides access to network slice instance and resources associated with it
NOTE: Network slice providers coordinate and aggregate network resources from multi-domain, multi-
technology networks.
Network Slice Subnet (NSS): subnet represents single or multiple networks under the control of an agent
NOTE: A complete network slice is inter-connection of subnets.
Network Slice Service Profile (NSSP): structure high-level format in which a network slice is described
slice: simplified text to represent 'network slice' in the context of the present document only
tenant: entity that consumes a network slice instance from network slice providers
NOTE: Such tenants do not care about implementation and technology details of the physical networks.
3.2 Abbreviations
For the purposes of the present document, the following abbreviations apply:
5GC 5G Core
API Application Programming Interface
BBF BroadBand Forum
DB DataBase
Diffserv Differentiated services
EVC Ethernet Virtual Circuit
FIB Forwarding Information Base
GSM Global System for Mobile
GSMA GSM Alliance
GST Generic Slice Template
IETF Internet Engineering Task Force
Intserv Integrated services
IP Internet Protocol
IPPM IP Performance Measurement
MANO MANagement and Orchestration (of NFV framework)
MPLS Multi-Protocol Layer Switching
NEST NEtwork Slice Template
NS Network Slice
NFV Network Function Virtualization
NG Next Generation
NGMN Next Generation Mobile Networks
NGNS Next Generation Network Slice
NS Network Slice
NSA Network Slice Agent
NSI Network Slice Instance
NSP Network Slice Provider
NSS Network Slice Subnet
NSSP Network Slice Service Profile
OAM Operations, Administration and Maintenance
PCE Path Computation Element
PCEP Path Computation Element Protocol
QoS Quality Of Service
RAN Radio Access Network
RSVP Resource Reservation Protocol
SDN Software Defined Networking
SDO Standards Developing Organization
SFC Service Function Chaining
SLA Service Level Agreement
TCAM Ternary Content-Addressable Memory
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TE Traffic Engineering
TEAS Traffic Engineering Architecture and Signaling
TED Traffic Engineering Database
UCL University College Of London
VDI Virtual Device Interface
VM Virtual Machine
VPN Virtual Private Network
VXLAN Virtual eXtensible Local Area Networks
WG Work Group
4 Network Slicing Architecture
4.1 Overview
Network slicing concept allows support of logical networks that are tailored for a specific service or set of services over
a shared common network infrastructure for the purpose of efficient utilization of network resources. NGMN white
paper [i.1] states that "the intention of a 5G slice is to provide only the traffic treatment that is necessary for the use case
and avoid all other unnecessary functionality". In this regard network slice is a framework aimed at providing flexible
on-boarding of newer verticals as a consequence of higher definition broadband, machine to machine communication,
industrial automation, advanced emergency services and so on [i.17]. These verticals cannot be served cost-effectively
by traditional network architectures because of the diversity of requirements. Network slicing techniques abstract
several infrastructures and provide a communication framework for verticals to build their own services.
There are several aspects that need to be resolved in terms of efficient resource scheduling, reservation and placement
mechanisms at the lower layers. Many of those aspects are either hardware or particular technology related. However, a
technology independent generalized reference framework for network slicing is very much needed to demonstrate how
information flows for the purpose of alignment of applications and data over dissimilar communication infrastructures.
The Next-gen network slicing (NGNS) framework defined here is a generalized architecture that would allow different
network service providers to coordinate and concurrently operate different services as active network slices.
4.2 Informative Background
Network slicing is an end to end paradigm initially discussed in the context of 5G to support new kind of applications
that need absolute resource guarantees in terms of latencies, bandwidth, jitter, reliability and privacy. The goal is an
ability to use common end to end infrastructure that is capable of delivering diverse services with their corresponding
assurance. Network slicing will be expensive, due to its inherently stringent resource assurance demands. Therefore,
network slices will be used to implement specific vertical markets and it does not imply to provide QoS to individual
streams.
Network slicing is a multi-technology solution that spans across multiple planes. There are several SDO activities that
focus on different aspects of the network slicing.
Since SDN and NFV are considered enabling techniques for network slicing, ETSI MANO, NFV ISGs activities are
concerned with the orchestration perspective that involves transforming a service using NFV infrastructure.
Many other standard activities at IETF are involved in distribution of services using SFC [i.5], segment routing [i.18] or
VPN mechanisms. Some additional efforts such as deterministic networks [i.19] provide data plane centric lower level
functionality to meet service assurances of bounded latency and bandwidth requirements.
3GPP network slice management [i.13], [i.14], [i.15] and [i.16] together provide provisioning and resource management
of RAN and 5GC slices. BBF has recently begun work on study of network slicing in the context of BBF architecture
(SD-406) [i.21]. ITU-T SG13 and SG15 have published several documents [i.10], [i.11] and [i.12] on the topic
motivated by IMT-2020 initiative and bulk of the effort is aligned with 3GPP related work in 5G domain.
GSMA NEST is an internal taskforce set to define a common language in the form of GST through which all operators
can describe parameters of a given slice type. GST specification [i.22] complements 3GPP slice/service type work by
providing its characteristics. The GST defines attributes applicable to slices in a 5G networks such as maximum packet
size, terminal density, uplink/downlink bandwidth, reliability and so on. The work will help different operators describe
a particular kind of slice in a standardized manner but it still requires a framework for propagation and realization of
these attributes which is not part of GST work.
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In contrast, proposed framework in NGP is independent of any underlying assumption about the enabling architecture,
protocol or methodology. It is also technology independent and concerns with both management and control aspects of
network slices. The gap identified here is to look at holistic solution of implementing network slices so that parts of the
networks enabling slices in parts can use common information aspects. It is our expectation that architectures from
different SDOs can be reduced to details in the present document.
The section 8.7.4 in the NG Scenario definitions [i.4] discusses NG slicing aspects and provides a conceptual view of
network slicing coordinators and agents. In the following clauses these components will be described in greater detail.
The NGNS information model puts together major components, managed information objects and interfaces that
provide clarity about end to end network slicing functionality. It does not apply directly to low-level control and data
plane functionality and provides coordination guidelines at the network level.
4.3 High level description
A Network slice is a description of a service aware logical network composed of different physical or virtual network
elements, resources and functions. A network slice is an independently managed instance of a logical network; It shares
underlying infrastructure with other independently managed instances. Since the infrastructure itself comprises of
different interconnected domains, essentially a slice can be seen as concatenated network of subnetworks belonging to
different network domains.
The NS methods are aimed at providing custom design of networks suitable for a specific use case (vertical market).
Such methods need to be able to translate a service requirement into normalized description of resources across
different type of network domains based on NGMN's description of network slicing, 3-layer approach [i.2] and is
reproduced below in Figure 1.
Figure 1: NGMN 3-Layer Network Slice and Service Concept
Network slice supports multi-tenancy for new set of services described in [i.1]. The focus is on the use cases that do not
necessarily fit into traditional virtual networking or VPN solutions. They require much higher degree of resource
assurance as well as stricter guarantees of those resource availabilities. For example, low-latency communications for
V2X, high-throughput for immersive multimedia applications, extremely reliable network for emergency response
situations. There are several differentiating aspects among these use cases from traditional isolation techniques, such as:
a) once allocated, the resource may be under the control of the network slice service operator (or tenant) for
autonomous control of the resources,
b) absolute guarantees should be met with, even under active contention of resources in other best-effort flows,
c) every flow (per stream QoS) should receive the assured treatment, i.e. two flows within the same slice should
not compete with each other.
Aligning with the NGMN's network slicing concept, there are three key areas of consideration for the NS architecture.
1) Service description (corresponds to service instance layer): A sketch of services instantiated, independent of
any technology or underlying control plane.
2) Network slice to abstract resource mapping (corresponds to network slice instance layer).
3) Resource allocation (across different networks).
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The present document describes a top-down structure and creates an information model corresponding to generalized
service aware NS. Through this model, tenant of a slice is able to express service constraints and requirements. The
primary contribution of present document is to identify the actors in NS architecture, the data necessary to be exchanged
between different actors, how they use it and the methods associated with the information.
4.4 Network slicing design principles
4.4.1 Service Oriented Approach
In order to provide scalability and flexibility in basic network slice architecture follows these principles:
• Abstraction
• Loose coupling
• Reusability
• Autonomy
The subsequent clauses will demonstrate how these are relevant in the network slice architecture.
4.4.2 Network slice abstraction
4.4.2.1 Motivation
Abstractions hide details of underlying implementation and technologies. It is important across heterogeneous (different
technologies) access and transit networks. Network slices offer a network through which a consumer can fulfil its
service delivery objectives. It should be agnostic of whether a particular technology, topology or routing protocol are
used. The slice specification should be well-defined and not adheres to a specific underlying solution.
4.4.2.2 Service lifecycle abstraction
This form of abstraction is dependent upon how much of the service logic is exposed as its capabilities. Each network
slice has well-known create, modify, get and delete methods associated for network aspects of the service. The users or
subscribers of a slice or internal data are hidden information, and a slice need not expose them.
4.4.2.3 Technology information abstraction
Any information about the underlying technology used within the service would result exposing extra information. It
might result in design of a service favouring a particular technology. This takes away, flexibility and reuse aspect of a
network slice. Network operations and resources relating to networks can be standardized in logical or abstract form so
that they remain independent of whether underlying transport is optical or packet based, MPLS or IP, or whether the
topology is L2 or L3. There will still be need for interconnections of two networks with different technologies.
4.4.2.4 Quality abstraction
Quality abstraction relates to the details provided within the service's accompanying service level agreement (SLA).
Network slices should only concern with network resource information and only with the quality parameters that impact
the communication aspect of the service. Separation of network and service logic policies is also necessary.
4.4.3 Loose coupling
It should be possible for network slices to be added and removed and altered flexibly across multiple administrative
domains. A loosely coupled network slice ensures that changes made within one network slice domain has no adverse
effects or unanticipated changes within other network domains and other network slice instances for that
matter. Interconnections between domains should be clear to help isolate problems in a network slice instance.
4.4.4 Network slice reusability
Many services have similar set of network requirements. The ability to compose a slice and describe its operations in a
reusable manner reduces system complexity.
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4.4.5 Slice autonomy
A network slice should have control over its own runtime environment. Each slice being an independent entity should
not impact the operations or lead service disruptions for other slices. Different type of virtual networks such as VxLAN,
VLANs implement autonomy partially through isolation. This implies packets forwarded or identified in a virtual
network are visible to other instances. In addition, it should be possible for a tenant operator of a slice to control and
manage resources as well as allocate them to different users or flows with in its own network slice.
5 Information Model
5.1 Reference Component Architecture

Figure 2: NS Reference Framework
The complete architecture with all the components (or actors) is described in Figure 2. There are three entities
interacting for the use of a network slice namely:
1) tenant;
2) Network Slice Provider (NSP); and
3) Network Slice Agent (NSA), associated with network infrastructure provider.
A tenant is a user of a network slice. Tenant creates a service with a particular network slice type. A network slice type
distinguishes the kind of network resources need to fulfil service requirements. An NS type is used as a guidance in
preparation of computing resources for a slice.
An NSP provides network slice as a service to tenant for control and operations of resources in the service. There may
be multiple NSPs (for instance virtual network operators) that may operate and manage its slices and tenants
independently.
An NSA is a network slice entity in infrastructure provider's domain. It understands processes and maps NSP's
information with in its domain. NSA is capable of extracting topology and operational state of its own network and
thereby coordinating with NSP to maintain its own portion of the network slice.
To explain the working of the framework, three most important aspects are:
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• Network slice managed objects: These are containers of information that should be shared between different
components. The description of objects in terms their relationship, scope and role help clearly define the
operation of network slices. The state of network slice can be extracted through these objects.
• Network slice Interfaces: These are the communications path over which information is collected and
distributed. Each interface is associated with well-defined functions.
• Network slice related functions: These are the set of functions in the framework and help define complete
workings of network slices.
5.2 Network service resource concept
5.2.1 Types of resources
The resources in the networks required by a network slice can be generalized to be of two types:
• Link resources
• Node resources
5.2.2 Link resources
Link resources relate to traffic or path related constraints and metrics. They comprise of bandwidth, delay, cost, packet
loss, redundancy etc. It is the expectation from the network that the resources are available at the time allocated request
is made, so that the congestion on the path associated with a service cannot happen if that's the requirement. Only
conditions that can cause failure to meet service assurances are faults and/or topology changes. This implies the portion
of link dedicated for network slice services may not contend with similar service for the life of the connection.
Similarly, it is assumed that the requested latency is met with guarantee through new and advanced scheduling
techniques in the data plane.
5.2.3 Node resources
Node resources can be generalized in a form of either compute or store. These resources comprise of network functions
such as firewall, routers or the service-based logic node, etc. Their behaviour and the data are decided by the tenant and
its interpretation is opaque to the NSA or NSP.
5.3 Network slice managed objects
5.3.1 General description
A top-level diagram Figure 3 of different managed objects and a brief description of relationship among them. Different
terms are described as follows.
Network slices are logically isolated network over multi-domain, multi-technology physical networks that provide
resource guarantees. Network slice providers offer different types of network slices as services to tenants. Physical
networks that participate in a slice are referred to as network slice subnets. The network slice entities in network slice
subnets is called network slice agents. Resources are described as nodes that perform specific function or links with
constraints such as bandwidth, packet loss and delay variation. Network slice service profile is a standard definition of
a particular type of network slice. It is described in terms of a network slice service graph that consists of service
nodes and service edges that can be customized by tenants. Network slice instance is a runtime instance of a service
profile with specific parameters and description of resources. Network slice service context represents the mapping of
network slice service to infrastructure resources while operations are methods associated with the network slice
instance.
In the following clauses important data related to these objects is described. Since this is a reference framework the
details of data, its format and structure are omitted from present document.
ETSI
14 ETSI GR NGP 011 V1.1.1 (2018-09)

Figure 3: Managed objects in network slice provider and agents
5.3.2 Discovered objects
5.3.2.1 Network slice subnet object
A NS subnet comprises of NS path topology object. This object is a set of links that traverse through subnet with traffic
parameters of latency, bandwidth, metrics associated and is exposed to the NSP. A NS subnet node can either be a
compute, storage node or a network function. Parameters associated with a node
...