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ONSEN Problem Statement
draft-kbf-onsen-problem-statement-00

Document Type Active Internet-Draft (individual)
Authors Samier Barguil , Kris Lambrechts , Chongfeng Xie
Last updated 2026-07-06
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draft-kbf-onsen-problem-statement-00
ONSEN Working Group                                           S. Barguil
Internet-Draft                                                     Nokia
Intended status: Informational                             K. Lambrechts
Expires: 7 January 2027                                          Intwine
                                                                  C. Xie
                                                           China Telecom
                                                             6 July 2026

                        ONSEN Problem Statement
                  draft-kbf-onsen-problem-statement-00

Abstract

   The IETF has produced numerous YANG data models for automating the
   provisioning and delivery of network and connectivity services,
   including L2SM, L3SM, L2NM, L3NM, Attachment Circuits, and Network
   Slicing models.  Despite their wide availability, operators report
   persistent challenges in operationalizing these abstractions in a
   consistent, scalable, and automatable manner.  This document
   describes the problem space for the ONSEN Working Group, identifying
   the operational gaps and deficiencies in existing IETF service and
   network abstraction models that prevent effective end-to-end
   automation.  The problems documented here are drawn from operator
   experience and from the findings of the IAB NEMOPS Workshop.  This
   document does not propose solutions, protocols, or new data models.

About This Document

   This note is to be removed before publishing as an RFC.

   The latest revision of this draft can be found at
   https://sbarguil.github.io/ONSEN_Problem_Statement/draft-kbf-onsen-
   problem-statement.html.  Status information for this document may be
   found at https://datatracker.ietf.org/doc/draft-kbf-onsen-problem-
   statement/.

   Discussion of this document takes place on the ONSEN Working Group
   mailing list (mailto:onsen@ietf.org), which is archived at
   https://mailarchive.ietf.org/arch/browse/onsen/.  Subscribe at
   https://www.ietf.org/mailman/listinfo/onsen/.

   Source for this draft and an issue tracker can be found at
   https://github.com/sbarguil/ONSEN_Problem_Statement.

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Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
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   Internet-Drafts are draft documents valid for a maximum of six months
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   time.  It is inappropriate to use Internet-Drafts as reference
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   This Internet-Draft will expire on 7 January 2027.

Copyright Notice

   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.
   Please review these documents carefully, as they describe your rights
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   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Conventions and Definitions . . . . . . . . . . . . . . . . .   4
   3.  Background  . . . . . . . . . . . . . . . . . . . . . . . . .   5
     3.1.  The RFC8969 Framework . . . . . . . . . . . . . . . . . .   5
     3.2.  The Service Models (LxSM) . . . . . . . . . . . . . . . .   7
     3.3.  The Network Models (LxNM) . . . . . . . . . . . . . . . .   7
     3.4.  Attachment Circuits (AC) and Service Attachment Points
           (SAP) . . . . . . . . . . . . . . . . . . . . . . . . . .   8
   4.  Operational Problems with Service and Network Abstractions  .   8
     4.1.  Fragmented Operational Lifecycles . . . . . . . . . . . .   8
       4.1.1.  Difficulty Integrating Different Management
               Domains . . . . . . . . . . . . . . . . . . . . . . .   8
       4.1.2.  Differing Lifecycle Semantics Across Abstractions . .   8
       4.1.3.  No Native Exposure of Lifecycle Attributes  . . . . .   9
       4.1.4.  Limited Support for Dynamic Lifecycle Management  . .   9

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       4.1.5.  Lack of Templates for Common Lifecycle Patterns . . .   9
       4.1.6.  Operational Silos . . . . . . . . . . . . . . . . . .   9
     4.2.  Inconsistent Models at the Same Abstraction Layer . . . .   9
       4.2.1.  Inconsistent Parameter Availability and Naming  . . .   9
       4.2.2.  Cannot Combine Service Instances Across LxSM
               Models  . . . . . . . . . . . . . . . . . . . . . . .   9
       4.2.3.  LxSM and Network Slice Service Relationship . . . . .  10
     4.3.  Misalignment Between Abstraction Layers . . . . . . . . .  10
       4.3.1.  No Clear Mapping From Service to Network Models . . .  10
       4.3.2.  No Clear Mapping From Network to Service Models . . .  10
       4.3.3.  Different Control-Plane Behaviors Across Vendors  . .  10
       4.3.4.  Inconsistent Service Semantics  . . . . . . . . . . .  10
     4.4.  Limited Observability and Feedback  . . . . . . . . . . .  11
       4.4.1.  Lack of Operational State in LxSM and LxNM Models . .  11
     4.5.  OSS/BSS Interface and API Interoperability  . . . . . . .  12
       4.5.1.  TMF 640/641 APIs and YANG Model Alignment . . . . . .  12
       4.5.2.  Divergence Between YANG Models and Generated APIs . .  12
     4.6.  Lack of Architectural Guidance and Documentation  . . . .  12
   5.  Evidence from the IAB NEMOPS Workshop . . . . . . . . . . . .  12
   6.  Operator Experiences  . . . . . . . . . . . . . . . . . . . .  13
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  13
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   9.  Informative References  . . . . . . . . . . . . . . . . . . .  13
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  14

1.  Introduction

   The IETF has produced several YANG data models that are instrumental
   for automating the provisioning and delivery of connectivity
   services, as described in [RFC8969].  These include models such as
   L3SM [RFC8299], L3NM [RFC9182], L2SM [RFC8466], L2NM [RFC9291] and
   Service Attachment Points (SAPs) [RFC9408].  Current IETF work adds
   on a YANG model for Network Slice Service [RFC9543],
   in[draft-ietf-teas-ietf-network-slice-nbi-yang-26].

   While some of these abstractions have been deployed, operators report
   persistent challenges in operationalizing them.  As highlighted by
   the IAB NEMOPS Workshop [NEMOPS], these challenges are systemic and
   operational in nature.  They are not confined to a specific
   technology or service type, but recur across abstraction domains and
   deployment environments.

   In addition, despite the availability of numerous YANG data models -
   covering configuration, assurance, and fault management - and the
   ongoing effort to make these models coexist within a common framework
   under the IETF umbrella, operators continue to face significant
   challenges in operationalizing YANG-based service APIs in a
   consistent, scalable, and interoperable manner.  While models such as

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   the L3SM, L2SM, L3NM, L2NM, AC/SAP abstractions and Network Slice
   Service each address specific aspects of service delivery, it is not
   always clear which models should be used together, in which
   scenarios, or to what extent a given implementation actually supports
   the full model.  The usage of these APIs remains fragmented - often
   partially implemented - and difficult to automate end-to-end.  In
   practice, APIs generated from similar YANG models often differ in
   service semantics, and the lack of clear guidance on model
   composition and interoperability complicates integration across
   systems, vendors, and deployment environments.

   The Operationalizing Network and SErvice abstractioNs (ONSEN) Working
   Group is chartered to address this problem space by focusing on the
   operational aspects of network and service abstractions.  It aims to
   make it easier to implement and use the IETF's service and network
   abstractions, with the goal of improving network automation,
   operational efficiency, and interoperability.

   This document defines the problem space for ONSEN.  It does not
   propose solutions, protocols, or new data models.

2.  Conventions and Definitions

   The following terms are used in this document:

   AC:  Attachment Circuit.

   Abstraction:  The process of defining simplified, high-level
      constructs that represent network and service-level capabilities,
      while hiding the details of their underlying realization.
      Abstraction enables interaction between management and automation
      systems without requiring direct exposure of device-specific
      configurations or protocol behaviors.

   LxNM:  Layer x Network Model (L2NM or L3NM).

   LxSM:  Layer x Service Model (L2SM or L3SM).

   NEMOPS:  Next Era of Network Management Operations.

   ONSEN:  Operationalizing Network and SErvice abstractioNs.

   OSS:  Operation Support Systems.

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3.  Background

   This section provides a brief overview of the existing IETF YANG
   model landscape relevant to the ONSEN problem space and the RFC 8969
   framework.  It describes the key data models that form the foundation
   of this work, including the L3VPN and L2VPN Service Models (L3SM,
   L2SM), the L3VPN and L2VPN Network Models (L3NM, L2NM), and the
   Attachment Circuit (AC) and Service Attachment Point (SAP)
   abstractions.  Together, these models define how services are
   specified, provisioned, and delivered across a provider's network.

3.1.  The RFC8969 Framework

   The YANG Automation Framework provides a programmatic approach to
   representing services and networks through data models.  It is
   designed to automate the management life cycle-including
   instantiation, provisioning, optimization, and monitoring-while
   enabling closed-loop control for adaptive service maintenance.

   The framework uses a layered approach to promote data reusability and
   prevent feature duplication across different management levels:

   *  Service Models: These are customer-facing modules that define
      high-level network services (e.g., L3VPN) independently of
      specific technologies.  They capture customer requirements such as
      communication scope (pipe, hose, or funnel) and performance
      guarantees.

   *  Network Models: These describe network-level abstractions across
      multiple devices, including topologies, resources, and protocols
      at the link and network layers.

   *  Device Models: Also known as Network Element models, these are
      technology-specific modules (e.g., BGP, ACL, or interface
      management) used to realize services on individual functions or
      hardware.

   The framework organizes automation into two primary procedural
   blocks:

   *  Service Life-Cycle Management: This manages the end-to-end service
      from a technology-independent perspective.

      -  Service Exposure: Captures services offered to customers via
         model catalogs.

      -  Service Creation/Modification: Validates resources and maps
         service requests to specific network or device models.

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      -  Service Assurance & Optimization: Uses telemetry to monitor
         performance against Service Level Agreements (SLAs) and
         dynamically adjusts configuration if objectives are not met.

      -  Service Diagnosis & Decommission: Provides OAM (Operations,
         Administration, and Maintenance) for troubleshooting and
         handles the release of resources when a service is terminated.

   *  Service Fulfillment Management: Focused on the technical execution
      and operational state at the device level.

      -  Intended Configuration Provision: Maps high-level service views
         into detailed device settings such as VRF definitions, IP
         layers, and QoS features.

      -  Configuration Validation: Ensures the intended configuration
         successfully takes effect in the operational datastore.

      -  Monitoring & Fault Diagnostics: Aggregates operational states
         to build network visibility and uses RPC (Remote Procedure
         Call) commands for fault isolation.

   The framework translates end-to-end abstract views into domain-
   specific views (mapping) and then into specific device-level modules
   (decomposition).  In practice, YANG Module Integration mechanisms
   such as Schema Mount allow multiple YANG modules to be combined into
   a tailored model for specific use cases.  It also includes Closed-
   Loop Control: by correlating telemetry data with configuration data,
   the framework allows orchestrators to continuously adjust network
   resources to meet intended service parameters.

   The primary benefits of the framework are:

   *  Vendor-Agnosticism: Enables unified management of multi-vendor
      environments through standardized interfaces.

   *  Operational Agility: Moves away from manual, device-specific
      configuration toward network-wide provisioning.

   *  Unified Orchestration: Allows orchestrators and controllers to
      manage resources across different network domains and layers.

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3.2.  The Service Models (LxSM)

   The L3VPN Service Model (L3SM) and the L2VPN Service Model (L2SM) are
   customer-facing YANG data models used to define the characteristics
   of network services between a customer and a service provider.  Both
   models act as abstracted interfaces for management systems (such as
   orchestrators) to automate the provisioning and management of VPN
   services.

   Defined in [RFC8299], the L3SM is used to deliver Layer 3 provider-
   provisioned VPN services, specifically limited to BGP PE-based VPNs.

   Defined in [RFC8466], the L2SM is used to configure and manage Layer
   2 provider-provisioned VPN services.  It supports point-to-point
   Virtual Private Wire Services (VPWS), multipoint Virtual Private LAN
   Services (VPLS), and Ethernet VPNs (EVPNs).  Both models include
   parameters for bandwidth, MTU, QoS, BUM traffic, and availability.

   Neither model is intended for the direct configuration of network
   elements; instead, an orchestration layer takes these models as input
   and translates them into technology-specific device models (such as
   BGP or interface configurations).

3.3.  The Network Models (LxNM)

   The L3VPN Network Model (L3NM) and the L2VPN Network Model (L2NM) are
   network-centric YANG data models designed to manage VPN services
   within a service provider's network.  While the Service Models focus
   on the customer's requirements, these Network Models provide an
   internal, resource-facing view used by controllers to automate
   technical configurations across multiple devices.  Both models
   preserve specific parameters for traffic management, covering
   bandwidth, MTU, QoS, and BUM traffic.

   Defined in [RFC9182], the L3NM is used for the internal provisioning
   of Layer 3 VPN services, specifically focusing on BGP PE-based VPNs
   and Multicast VPNs.

   Defined in [RFC9291], the L2NM is the network-centric counterpart to
   the L2SM, providing the internal view required to instantiate Layer 2
   services.  It covers a wide range of L2VPNs, including VPLS, VPWS,
   and various EVPN flavors (EVPN over MPLS, VXLAN, and PBB-EVPN).

   Unlike customer-facing service models, these models can expose
   internal operational states and performance metrics to help
   controllers continuously adjust the network to meet SLAs.

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3.4.  Attachment Circuits (AC) and Service Attachment Points (SAP)

   In the context of the YANG Automation Framework, Attachment Circuits
   (ACs) and Service Attachment Points (SAPs) are fundamental
   abstractions used to define how customer networks connect to a
   provider's network and where services are delivered.

   An Attachment Circuit, as defined in [RFC9408], is a physical or
   logical channel that connects a Customer Edge (CE) device to a
   Provider Edge (PE) device.

   A Service Attachment Point is an abstract network reference point -
   typically the PE side of an AC - where network services are actually
   delivered or "grafted" to the customer.  The SAP Network Model {
   {RFC9408}} provides an abstract view of the provider's topology,
   exposing only the nodes and interfaces where services can be
   attached.

4.  Operational Problems with Service and Network Abstractions

   This section identifies the core operational problems that motivate
   the ONSEN Working Group.  Each problem is described in terms of its
   operational impact and why it cannot be resolved by implementing
   automation of the existing LxNM/LxSM models in their current forms.

4.1.  Fragmented Operational Lifecycles

   Operational workflows associated with service abstractions - service
   instantiation, monitoring, modification, troubleshooting, and
   decommissioning - are often fragmented and inconsistently handled.

4.1.1.  Difficulty Integrating Different Management Domains

   Despite the availability of numerous YANG data models, operators
   depend on a heterogeneous mix of models, vendor-specific APIs, and
   legacy mechanisms (CLI, SNMP), even within a single deployment.

4.1.2.  Differing Lifecycle Semantics Across Abstractions

   Lifecycle actions initiated through YANG-based service APIs often
   require coordination across orchestration systems, controllers, and
   device configurations, but these components are rarely aligned in
   terms of lifecycle semantics or data models.

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4.1.3.  No Native Exposure of Lifecycle Attributes

   Existing service and network abstractions lack native constructs to
   express lifecycle attributes such as activation time, duration,
   expiration, or rollback behavior.  Transient service intents must
   therefore be tracked and enforced outside the abstraction framework.

4.1.4.  Limited Support for Dynamic Lifecycle Management

   Existing service and network abstractions are primarily designed for
   static, long-lived services.  They provide limited support for
   dynamic lifecycle management, such as on-demand service
   instantiation, dynamic bandwidth adjustment, or temporary service
   suspension.  Operators must implement custom lifecycle management
   logic outside the abstraction framework, which increases operational
   complexity and reduces automation reliability.

4.1.5.  Lack of Templates for Common Lifecycle Patterns

   The LxSM models do not provide templates or reusable constructs to
   aid operators in reducing the input parameters required for common
   site deployment patterns.  Operators must manually configure each
   service instance, which increases the risk of misconfiguration and
   reduces operational efficiency.

4.1.6.  Operational Silos

   Configuration management and the collection of statistics / telemetry
   data continue to exist as separate silos in both the organizational
   chart and technology stacks/APIs.

4.2.  Inconsistent Models at the Same Abstraction Layer

4.2.1.  Inconsistent Parameter Availability and Naming

   Very similar, if not identical, features and functionality across
   different models at the same abstraction layer are often using
   slightly different parameters names, a different YANG data type or is
   not configurable to the same level of detail.

4.2.2.  Cannot Combine Service Instances Across LxSM Models

   An operator offering a diverse set of services (L3VPN, L2VPN,
   internet access, etc.) cannot use the LxSM models to offer a
   combination of these services through a consistent representation on
   the same orchestrator.

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4.2.3.  LxSM and Network Slice Service Relationship

   The published LxSM models and
   [draft-ietf-teas-ietf-network-slice-nbi-yang-26] act as Service
   Models with a similar level of abstraction.  Operators need guidance
   on the use cases for both model sets, and when one should be used
   versus the other or whether both can, and should be, combined for a
   given deployment scenarios.

4.3.  Misalignment Between Abstraction Layers

   Service abstractions are realized through a combination of service-
   level models, network-level models, control-plane behavior, and
   management interfaces.  These layers are often developed
   independently, with limited coordination across working groups or
   operational domains.

4.3.1.  No Clear Mapping From Service to Network Models

   Some service abstractions do not have a clear mapping to underlying
   network models, making it difficult to implement and automate end-to-
   end service provisioning.

4.3.2.  No Clear Mapping From Network to Service Models

   The Network Models (LxNM) expose parameters that are have no
   equivalent in the Service Models (LxSM), making it difficult to
   implement a consistent mapping.

4.3.3.  Different Control-Plane Behaviors Across Vendors

   Control-plane behaviors (vendor differentiators) that are difficult
   to correlate with service-level intent.

4.3.4.  Inconsistent Service Semantics

   Abstraction models frequently rely on metrics, attributes, or
   parameters whose semantics vary across vendors, models,
   implementations, or consumption contexts.  Concepts such as cost,
   availability, or performance may be represented using different
   definitions, units, scopes, or update frequencies.

   *  APIs derived from similar intentions differ in service semantics
      across vendors and deployments, complicating integration for
      operators and OSS/BSS systems.

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   *  The lack of consistent guidance on how abstractions should be
      modeled, exposed, and consumed results in APIs that vary
      significantly across vendors and deployments.

   *  Inconsistent semantics complicate integration between systems and
      undermine the reliability of automation, typically addressed
      through custom logic or manual processes that reduce portability
      and interoperability.

4.4.  Limited Observability and Feedback

   Existing abstractions primarily focus on configuration and offer
   limited standardized mechanisms for reporting whether requested
   behaviors have been successfully applied or remain valid over time.

   *  Operators have limited ability to validate whether service intent
      is being met over time or to correlate operational state across
      abstraction layers.  Operational considerations such as alarms,
      notifications, and state changes triggered by service updates are
      not comprehensively addressed in the existing Service and Network
      Models, further hindering end-to-end observability.

   *  The lack of consistent feedback undermines closed-loop automation
      and complicates troubleshooting, particularly in multi-vendor and
      multi-domain environments.

   *  This lack of feedback assurance increases reliance on manual
      monitoring and intervention.

4.4.1.  Lack of Operational State in LxSM and LxNM Models

   Some of the LxSM and LxNM models provide operational state
   information, but this is not consistent across models, and the
   information provided is often insufficient for operators to determine
   whether the service is functioning as intended.

   For example, the L3SM model does not provide any operational state
   information, while the L2SM model provides some operational state
   information, but it is limited to the status of the service and does
   not include e.g. details on SLO violations or other operational
   metrics that would be useful for troubleshooting and monitoring.

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4.5.  OSS/BSS Interface and API Interoperability

   YANG data models are commonly used as the basis for APIs that expose
   service abstractions to external systems.  However, existing work
   provides limited guidance on how these abstractions should be
   exposed, versioned, or consumed in a predictable and interoperable
   manner.

4.5.1.  TMF 640/641 APIs and YANG Model Alignment

   Some operators adopt TMF640/641 as APIs for service ordering from
   their BSS, but how these interfaces can be aligned with service/
   network YANG models is not specified.  Operators face the challenge
   of either paying commercial OSS/BSS providers to create bespoke
   interfaces or building an adaptation layer themselves.

4.5.2.  Divergence Between YANG Models and Generated APIs

   APIs generated from similar YANG models often differ in service
   semantics, complicating integration across systems, vendors, and
   deployment environments.

4.6.  Lack of Architectural Guidance and Documentation

   A recurring theme from the NEMOPS discussions is the absence of
   architectural documentation and operational guidance explaining how
   existing abstractions, models, protocols, and tools are intended to
   work together as a system.

   *  Operators express difficulty understanding which abstractions to
      use, how they should be combined, and how responsibilities are
      divided across layers and working groups.

   *  The absence of cohesive guidance leads to divergent
      interpretations and inconsistent deployments.

5.  Evidence from the IAB NEMOPS Workshop

   This section summarizes the relevant findings of the IAB NEMOPS
   Workshop [NEMOPS] that corroborate the problems identified in
   Section 4.

   *  Despite significant progress in protocol development and data
      modeling, operational workflows remain fragmented and difficult to
      automate end-to-end.

   *  Model-driven network management is generally successful, yet
      insufficient on its own to address higher-level operational needs.

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   *  Gaps between device-level and service-level abstractions: existing
      models often lack the semantic alignment and contextual
      information required by orchestration and OSS/BSS systems.

   *  Operators must perform extensive model mapping, data
      transformation, and system-specific integration outside the scope
      of standardized abstractions.

   *  Limited ability to validate whether service intent is being met
      over time or to correlate operational state across abstraction
      layers.

   *  Additional operator-reported challenges to be added here from
      contributors.

6.  Operator Experiences

   TODO

   This section documents operational problems reported directly by
   network operators.  To be populated by operator contributors.

7.  IANA Considerations

   This memo includes no request to IANA.

8.  Security Considerations

   TODO

9.  Informative References

   [draft-ietf-teas-ietf-network-slice-nbi-yang-26]
              "A YANG Data Model for the RFC 9543 Network Slice
              Service", n.d., <https://datatracker.ietf.org/doc/html/
              draft-ietf-teas-ietf-network-slice-nbi-yang-26>.

   [NEMOPS]   "IAB Workshop Report: Next Era of Network Management
              Operations (NEMOPS)", n.d.,
              <https://datatracker.ietf.org/doc/draft-ietf-nemops-
              workshop-report/>.

   [RFC8299]  Wu, Q., Ed., Litkowski, S., Tomotaki, L., and K. Ogaki,
              "YANG Data Model for L3VPN Service Delivery", RFC 8299,
              DOI 10.17487/RFC8299, January 2018,
              <https://www.rfc-editor.org/rfc/rfc8299>.

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   [RFC8466]  Wen, B., Fioccola, G., Ed., Xie, C., and L. Jalil, "A YANG
              Data Model for Layer 2 Virtual Private Network (L2VPN)
              Service Delivery", RFC 8466, DOI 10.17487/RFC8466, October
              2018, <https://www.rfc-editor.org/rfc/rfc8466>.

   [RFC8969]  Wu, Q., Ed., Boucadair, M., Ed., Lopez, D., Xie, C., and
              L. Geng, "A Framework for Automating Service and Network
              Management with YANG", RFC 8969, DOI 10.17487/RFC8969,
              January 2021, <https://www.rfc-editor.org/rfc/rfc8969>.

   [RFC9182]  Barguil, S., Gonzalez de Dios, O., Ed., Boucadair, M.,
              Ed., Munoz, L., and A. Aguado, "A YANG Network Data Model
              for Layer 3 VPNs", RFC 9182, DOI 10.17487/RFC9182,
              February 2022, <https://www.rfc-editor.org/rfc/rfc9182>.

   [RFC9291]  Boucadair, M., Ed., Gonzalez de Dios, O., Ed., Barguil,
              S., and L. Munoz, "A YANG Network Data Model for Layer 2
              VPNs", RFC 9291, DOI 10.17487/RFC9291, September 2022,
              <https://www.rfc-editor.org/rfc/rfc9291>.

   [RFC9408]  Boucadair, M., Ed., Gonzalez de Dios, O., Barguil, S., Wu,
              Q., and V. Lopez, "A YANG Network Data Model for Service
              Attachment Points (SAPs)", RFC 9408, DOI 10.17487/RFC9408,
              June 2023, <https://www.rfc-editor.org/rfc/rfc9408>.

   [RFC9543]  Farrel, A., Ed., Drake, J., Ed., Rokui, R., Homma, S.,
              Makhijani, K., Contreras, L., and J. Tantsura, "A
              Framework for Network Slices in Networks Built from IETF
              Technologies", RFC 9543, DOI 10.17487/RFC9543, March 2024,
              <https://www.rfc-editor.org/rfc/rfc9543>.

Authors' Addresses

   Samier Barguil
   Nokia
   Email: samier.barguil_giraldo@nokia.com

   Kris Lambrechts
   Intwine
   Email: kris@intwine.net

   Chongfeng Xie
   China Telecom
   Email: xiechf@chinatelecom.cn

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