CCAMP Working Group                                                C. Yu
Internet-Draft                                                   I. Busi
Intended status: Standards Track                     Huawei Technologies
Expires: 5 September 2022                                         A. Guo
                                                  Futurewei Technologies
                                                              S. Belotti
                                                                   Nokia
                                                          J.-F. Bouquier
                                                                Vodafone
                                                            F. Peruzzini
                                                                     TIM
                                                     O. Gonzalez de Dios
                                                              Telefonica
                                                                V. Lopez
                                                                   Nokia
                                                            4 March 2022


            A YANG Data Model for Network Hardware Inventory
              draft-yg3bp-ccamp-network-inventory-yang-00

Abstract

   This document defines a YANG data model for network hardware
   inventory data information.

   The YANG data model presented in this document is intended to be used
   as the basis toward a generic YANG data model for network hardware
   inventory data information which can be augmented, when required,
   with technology-specific (e.g., optical) inventory data, to be
   defined either in a future version of this document or in another
   document.

   The YANG data model defined in this document conforms to the Network
   Management Datastore Architecture (NMDA).

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
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.






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   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 5 September 2022.

Copyright Notice

   Copyright (c) 2022 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
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Revised BSD License text as
   described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology and Notations . . . . . . . . . . . . . . . .   4
     1.2.  Requirements Notation . . . . . . . . . . . . . . . . . .   5
     1.3.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   6
     1.4.  Prefix in Data Node Names . . . . . . . . . . . . . . . .   6
   2.  YANG Data Model for Network Hardware Inventory  . . . . . . .   6
     2.1.  YANG Model Overview . . . . . . . . . . . . . . . . . . .   6
     2.2.  Efficiency Issue  . . . . . . . . . . . . . . . . . . . .   9
   3.  Network Hardware Inventory Tree Diagram . . . . . . . . . . .  10
   4.  YANG Model for Network Hardware Inventory . . . . . . . . . .  11
   5.  Manageability Considerations  . . . . . . . . . . . . . . . .  17
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  18
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  18
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  18
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  18
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  19
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  19
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  19

1.  Introduction

   Network hardware inventory management is a key component in
   operators' OSS architectures.





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   Network inventory is a fundamental functionality in network
   management and was specified many years ago.  Given the emerging of
   data models and their deployment in operator's management and control
   systems, the traditional function of inventory management is also
   requested to be defined as a data model.

   Network inventory management and monitoring is a critical part of
   ensuring the network stays healthy, well-planned, and functioning in
   the operator's network.  Network inventory management allows the
   operator to keep track of what physical network devices are staying
   in the network including relevant software and hardware.

   The network inventory management also helps the operator to know when
   to acquire new assets and what is needed, or to decommission old or
   faulty ones, which can help to improve network performance and
   capacity planning.

   In [I-D.ietf-teas-actn-poi-applicability] a gap was identified
   regarding the lack of a YANG data model that could be used at ACTN
   MPI interface level to report whole/partial hardware inventory
   information available at PNC level towards north-bound systems (e.g.,
   MDSC or OSS layer).

   [RFC8345] initial goal was to make possible the augmentation of the
   YANG data model with network inventory data model but this was never
   developed and the scope was kept limited to network topology data
   only.

   It is key for operators to drive the industry towards the use of a
   standard YANG data model for network inventory data instead of using
   vendors proprietary APIs (e.g., REST API).

   In the ACTN architecture, this would bring also clear benefits at
   MDSC level for packet over optical integration scenarios since this
   would enable the correlation of the inventory information with the
   links information reported in the network topology model.

   The intention is to define a generic YANG data model that would be as
   much as possible technology agnostic (valid for IP, optical and
   microwave networks) and that could be augmented, when required, to
   include some technology-specific inventory details.

   [RFC8348] defines a YANG data model for the management of the
   hardware on a single server and therefore it is more applicable to
   the PNC South Bound Interface (SBI) towards the network elements
   rather than at the PNC MPI.  However, the YANG data model defined in
   [RFC8348] has been used as a reference for defining the YANG network
   hardware inventory data model.



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   For optical network hardware inventory, the network inventory YANG
   data model should support the use cases (4a and 4b) and requirements
   defined in [ONF_TR-547], in order to guarantee a seamless integration
   at MDSC/OSS/orchestration layers.

   The proposed YANG data model has been analyzed to cover the
   requirements and use cases for Optical Network Hardware Inventory.

   Being based on [RFC8348], this data model should be a good starting
   point toward a generic data model and applicable to any technology.
   However, further analysis of requirements and use cases is needed to
   extend the applicability of this YANG data model to other types of
   networks (IP and microwave) and to identify which aspects are generic
   and which aspects are technology-specific for optical networks.

   This document defines one YANG module: ietf-network-inventory.yang
   (Section 4).

   Note: review in future versions of this document the related modules,
   depending on the augmentation relationship.

   The YANG data model defined in this document conforms to the Network
   Management Datastore Architecture [RFC8342].

1.1.  Terminology and Notations

   The following terms are defined in [RFC7950] and are not redefined
   here:

   *  client

   *  server

   *  augment

   *  data model

   *  data node

   The following terms are defined in [RFC6241] and are not redefined
   here:

   *  configuration data

   *  state data

   The terminology for describing YANG data models is found in
   [RFC7950].



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   TBD: Recap the concept of chassis/slot/component/board/... in
   [TMF-MTOSI].

   Following terms are used for the representation of the hierarchies in
   the network hardware inventory.

   Network Element:

      a device installed on one or several chassis and can afford some
      specific transmission function independently.

   Rack:

      a holder of the device and provides power supply for the device in
      it.

   Chassis:

      a holder of the device installation.

   Slot:

      a holder of the board.

   Component:

      holders and equipments of the network element, including chassis,
      slot, sub-slot, board and port.

   Board/Card:

      a pluggable equipment can be inserted into one or several slots/
      sub-slots and can afford a specific transmission function
      independently.

   Port:

      an interface on board

1.2.  Requirements Notation

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.





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1.3.  Tree Diagram

   A simplified graphical representation of the data model is used in
   Section 3 of this document.  The meaning of the symbols in these
   diagrams is defined in [RFC8340].

1.4.  Prefix in Data Node Names

   In this document, names of data nodes and other data model objects
   are prefixed using the standard prefix associated with the
   corresponding YANG imported modules, as shown in the following table.

              +========+========================+===========+
              | Prefix | Yang Module            | Reference |
              +========+========================+===========+
              | ianahw | iana-hardware          | [RFC8348] |
              +--------+------------------------+-----------+
              | ni     | ietf-network-inventory | RFCXXX    |
              +--------+------------------------+-----------+
              | yang   | ietf-yang-types        | [RFC6991] |
              +--------+------------------------+-----------+

                  Table 1: Prefixes and corresponding YANG
                                  modules

   RFC Editor Note: Please replace XXXX with the RFC number assigned to
   this document.  Please remove this note.

2.  YANG Data Model for Network Hardware Inventory

2.1.  YANG Model Overview

   Based on TMF classification in [TMF-MTOSI], inventory objects can be
   divided into two groups, holder group and equipment group.  The
   holder group contains rack, chassis, slot, sub-slot while the
   equipment group contains network-element, board and port.  With the
   requirement of GIS and on-demand domain controller selection raised,
   the equipment room becomes a new inventory object to be managed
   besides TMF classification.

   Logically, the relationship between these inventory objects can be
   described by Figure 1 below:









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                   +-------------+
                   |  inventory  |
                   +-------------+
                       // \\
                 1:N  //   \\ 1:M
                     //     \\
     +----------------+     +-----------------+
     | equipment room |     | network element |
     +----------------+     +-----------------+
             ||                     ||
             || 1:N                 ||
             \/                     ||
       +------------+               ||1:M
       |    rack    |               ||
       +------------+               ||
             ||                     ||
             || 1:N                 \/
             ||______________\+------------+
             |---------------/|   chassis  |
                              +------------+
                                    ||
                     ______1:N______||_____1:M_______
                     ||------------------ ---------||
                     \/                            \/
              +--------------+               +-----------+
              | slot/subslot |               |   board   |
              +--------------+               +-----------+
                                                   ||
                                                   ||1:N
                                                   \/
                                             +-----------+
                                             |    port   |
                                             +-----------+

              Figure 1: Relationship between inventory objects

   In [RFC8348], rack, chassis, slot, sub-slot, board and port are
   defined as components of network elements with generic attributes.

   While [RFC8348] is used to manage the hardware of a single server
   (e.g., a Network Element), the Network Inventory YANG data model is
   used to retrieve the network hardware inventory information that a
   controller discovers from multiple Network Elements under its
   control.

   However, the YANG data model defined in [RFC8348] has been used as a
   reference for defining the YANG network inventory data model.  This
   approach can simplify the implementation of this network hardware



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   inventory model when the controller uses the YANG data model defined
   in [RFC8348] to retrieve the hardware from the network elements under
   its control.

   Note: review in future versions of this document which attributes
   from [RFC8348] are required also for network hardware inventory and
   whether there are attributes not defined in [RFC8348] which are
   required for network hardware inventory

   Note: review in future versions of this document whether to re-use
   definitions from [RFC8348] or use schema-mount.

     +--ro network-inventory
        +--ro equipment-rooms
        |  +--ro equipment-room* [uuid]
        |     +--ro uuid        yang:uuid
        |     ...................................
        |     +--ro rack* [uuid]
        |        +--ro uuid           yang:uuid
        |        ...................................
        |        +--ro chassis* [uuid]
        |           +--ro uuid            yang:uuid
        |           ...................................
        |           +--ro chassis-ref
        |              +--ro ne-ref?          leafref
        |              +--ro component-ref?   leafref
        +--ro network-elements
           +--ro network-element* [uuid]
              +--ro uuid          yang:uuid
              ...................................
              +--ro components
                 +--ro component* [uuid]
                    +--ro uuid              yang:uuid
                    ...................................

   The YANG data model for network hardware inventory follows the same
   approach of [RFC8348] and reports the network hardware inventory as a
   list of components with different types (e.g., chassis, module,
   port).












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     +--ro components
        +--ro component* [uuid]
           +--ro uuid              yang:uuid
           +--ro name?             string
           +--ro description?      string
           +--ro class?            identityref
           +--ro parent-rel-pos?   int32
           +--ro children* [child-ref]
           |  +--ro child-ref    -> ../../uuid
           +--ro parent
              +--ro parent-ref?   -> ../../uuid

   Note: review in future versions of this document whether the
   component list should be under the network-inventory instead of under
   the network-element container

   However, considering there are some special scenarios, the
   relationship between the rack and network elements is not 1 to 1 nor
   1 to n.  The network element cannot be the direct parent node of the
   rack.  So there should be n to m relationship between racks and
   network elements.  And the chassis in the rack should have some
   reference information to the component.

   Note that in [RFC8345], topology and inventory are two subsets of
   network information.  However, considering the complexity of the
   existing topology models and to have a better extension capability,
   we define a separate root for the inventory model.  We will consider
   some other ways to do some associations between the topology model
   and inventory model in the future.

   Note: review in future versions of this document whether network
   hardware inventory should be defined as an augmentation of the
   network model defined in [RFC8345] instead of under a new network-
   inventory root.

   The proposed YANG data model has been analysed to cover the
   requirements and use cases for Optical Network Inventory.

   Further analysis of requirements and use cases is needed to extend
   the applicability of this YANG data model to other types of networks
   (IP and microwave) and to identify which aspects are generic and
   which aspects are technology-specific for optical networks.

2.2.  Efficiency Issue

   During doing the design of integration with OSS, some efficiency
   issues have been discovered.  More discussion is needed to be done in
   the future to address this issue.



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   Considering relational database is widely used by traditional OSS
   systems and part of PNCs, the inventory objects are probably saved in
   different tables.  If the generic model is adopted, when doing a full
   amount synchronization, PNC needs to convert all inventory objects of
   each NE into component objects and mix them together into a list, and
   then construct a response and send to OSS or MDSC.  The OSS or MDSC
   needs to classify the component list and devide them into different
   groups, in order to save them in different tables.  The mixing-
   regrouping steps are actually waste of effort.

   And this efficiency issue will be more serious in a larger scale of
   network.

3.  Network Hardware Inventory Tree Diagram

   Figure 2 below shows the tree diagram of the YANG data model defined
   in module ietf-network-inventory.yang (Section 4).


































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   module: ietf-network-inventory
     +--ro network-inventory
        +--ro equipment-rooms
        |  +--ro equipment-room* [uuid]
        |     +--ro uuid        yang:uuid
        |     +--ro name?       string
        |     +--ro location?   string
        |     +--ro rack* [uuid]
        |        +--ro uuid           yang:uuid
        |        +--ro name?          string
        |        +--ro row-number?    uint32
        |        +--ro rack-number?   uint32
        |        +--ro chassis* [uuid]
        |           +--ro uuid              yang:uuid
        |           +--ro name?             string
        |           +--ro chassis-number?   uint8
        |           +--ro chassis-ref
        |              +--ro ne-ref?          leafref
        |              +--ro component-ref?   leafref
        +--ro network-elements
           +--ro network-element* [uuid]
              +--ro uuid          yang:uuid
              +--ro name?         string
              +--ro components
                 +--ro component* [uuid]
                    +--ro uuid              yang:uuid
                    +--ro name?             string
                    +--ro description?      string
                    +--ro class?            identityref
                    +--ro parent-rel-pos?   int32
                    +--ro children* [child-ref]
                    |  +--ro child-ref    -> ../../uuid
                    +--ro parent
                       +--ro parent-ref?   -> ../../uuid

                  Figure 2: Network inventory tree diagram

4.  YANG Model for Network Hardware Inventory

   <CODE BEGINS> file "ietf-network-inventory@2022-03-04.yang"
   module ietf-network-inventory {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-network-inventory";
     prefix ni;

     import ietf-yang-types {
       prefix yang;
       reference



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         "RFC6991: Common YANG Data Types.";
     }

     import iana-hardware {
       prefix ianahw;
       reference
         "RFC 8348: A YANG Data Model for Hardware Management.";
     }

     organization
       "IETF CCAMP Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/ccamp/>
        WG List:  <mailto:ccamp@ietf.org>

        Editor:   Chaode Yu
                  <yuchaode@huawei.com>

        Editor:   Italo Busi
                  <italo.busi@huawei.com>

        Editor:   Aihua Guo
                  <aihuaguo.ietf@gmail.com>

        Editor:   Sergio Belotti
                  <sergio.belotti@nokia.com>

        Editor:   Jean-Francois Bouquier
                  <jeff.bouquier@vodafone.com>

        Editor:   Fabio Peruzzini
                  <fabio.peruzzini@telecomitalia.it>";

     description
       "This module defines a model for retrieving network inventory.

       The model fully conforms to the Network Management
       Datastore Architecture (NMDA).

       Copyright (c) 2021 IETF Trust and the persons
       identified as authors of the code.  All rights reserved.

       Redistribution and use in source and binary forms, with or
       without modification, is permitted pursuant to, and subject
       to the license terms contained in, the Simplified BSD License
       set forth in Section 4.c of the IETF Trust's Legal Provisions
       Relating to IETF Documents
       (https://trustee.ietf.org/license-info).



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       This version of this YANG module is part of RFC XXXX; see
       the RFC itself for full legal notices.

       The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
       NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
       'MAY', and 'OPTIONAL' in this document are to be interpreted as
       described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
       they appear in all capitals, as shown here.";

     // RFC Ed.: replace XXXX with actual RFC number and remove this
     // note.
     // RFC Ed.: update the date below with the date of RFC publication
     // and remove this note.

     revision 2022-03-04 {
       description
         "Initial revision.";
       reference
         "draft-yg3bp-ccamp-inventory-yang-00: A YANG Data
         Model for Network Inventory.";
     }

     container network-inventory {
       config false;
       description
         "The top-level container for the network inventory
         information.";
       uses equipment-rooms-grouping;
       uses network-elements-grouping;
     }

     grouping common-entity-attributes {
       description
         "A set of attributes which are common to all the entities
         (e.g., component, equipment room) defined in this module.";
       leaf uuid {
         type yang:uuid;
         description
           "Uniquely identifies an entity (e.g., component).";
       }
       leaf name {
         type string;
         description
           "A name for an entity (e.g., component), as specified by
           a network manager, that provides a non-volatile 'handle'
           for the entity and that can be modified anytime during the
           entity lifetime.




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           If no configured value exists, the server MAY set the value
           of this node to a locally unique value in the operational
           state.";
       }
     }
     grouping network-elements-grouping {
       description
         "The attributes of the network elements.";
       container network-elements {
         description
           "The container for the list of network elements.";
         list network-element {
           key uuid;
           description
             "The list of network elements within the network.";
           uses common-entity-attributes;
           uses components-grouping;
         }
       }
     }

     grouping equipment-rooms-grouping {
       description
         "The attributes of the equipment rooms.";
       container equipment-rooms {
         description
           "The container for the list of equipment rooms.";
         list equipment-room {
           key uuid;
           description
             "The list of equipment rooms within the network.";
           uses common-entity-attributes;
           leaf location {
             type string;
             description
               "compared with the location information of the other
               inventory objects, a GIS address is preferred for
               equipment room";
           }
           list rack {
             key uuid;
             description
               "The list of racks within an equipment room.";
             uses common-entity-attributes;
             leaf row-number {
               type uint32;
               description
                 "Identifies the row within the equipment room where



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                 the rack is located.";
             }
             leaf rack-number {
               type uint32;
               description
                 "Identifies the physical location of the rack within
                 the row.";
             }
             list chassis {
               key uuid;
               description
                 "The list of chassis within a rack.";
               uses common-entity-attributes;
               leaf chassis-number {
                 type uint8;
                 description
                   "Identifies the location of the chassis within the
                   rack.";
               }
               container chassis-ref {
                 description
                   "The reference to the network element component
                   representing this chassis.";
                 leaf ne-ref {
                   type leafref {
                     path "/ni:network-inventory/ni:network-elements"
                       + "/ni:network-element/ni:uuid";
                   }
                   description
                     "The reference to the network element containing
                     the component.";
                 }
                 leaf component-ref {
                   type leafref {
                     path "/ni:network-inventory/ni:network-elements"
                        + "/ni:network-element[ni:uuid"
                        + "=current()/../ne-ref]/ni:components"
                        + "/ni:component/ni:uuid";
                   }
                   description
                     "The reference to the component within the network
                     element.";
                 }
               }
             }
           }
         }
       }



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     }

     grouping components-grouping {
       description
         "The attributes of the hardware components.";
       container components {
         description
           "The container for the list of components.";
         list component {
           key uuid;
           description
             "The list of components within a network element.";
           uses common-entity-attributes;
           leaf description {
             type string;
             description
               "A textual description of the component.";
             reference
               "RFC 8348: A YANG Data Model for Hardware Management.";
           }
           leaf class {
             type identityref {
               base ianahw:hardware-class;
             }
             description
               "An indication of the general hardware type of the
                component.";
             reference
               "RFC 8348: A YANG Data Model for Hardware Management.";
           }
           leaf parent-rel-pos {
             type int32 {
               range "0 .. 2147483647";
             }
             description
               "An indication of the relative position of this child
                component among all its sibling components.  Sibling
                components are defined as components that:

                  o share the same value of the 'parent' node and

                  o share a common base identity for the 'class' node.";
             reference
               "RFC 8348: A YANG Data Model for Hardware Management.";
           }
           list children {
             key child-ref;
             description



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               "The child components that are physically contained by
               this component.";

             leaf child-ref {
               type leafref {
                 path "../../ni:uuid";
               }
               description
                 "The reference to the child component.";
             }
           }
           container parent {
             description
               "The parent component that physically contains this
                component.

                If this container is not instantiated, it indicates
                that this component is not contained in any other
                component.

                In the event that a physical component is contained by
                more than one physical component (e.g., double-wide
                modules), this container contains the data of one of
                these components.  An implementation MUST use the same
                component every time this container is instantiated.";
             leaf parent-ref {
               type leafref {
                 path "../../ni:uuid";
               }
               description
                 "The reference to the parent component.";
             }
           }
         }
       }
     }
   }
   <CODE ENDS>

                  Figure 3: Network inventory YANG module

5.  Manageability Considerations

   <Add any manageability considerations>







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6.  Security Considerations

   <Add any security considerations>

7.  IANA Considerations

   <Add any IANA considerations>

8.  References

8.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8348]  Bierman, A., Bjorklund, M., Dong, J., and D. Romascanu, "A
              YANG Data Model for Hardware Management", RFC 8348,
              DOI 10.17487/RFC8348, March 2018,
              <https://www.rfc-editor.org/info/rfc8348>.




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   [TMF-MTOSI]
              TM Forum (TMF), "TMF MTOSI 4.0 Equipment Model", TMF
              SD2-20_EquipmentModel , 2008,
              <https://www.tmforum.org/resources/suite/mtosi-4-0/>.

8.2.  Informative References

   [I-D.ietf-teas-actn-poi-applicability]
              Peruzzini, F., Bouquier, J., Busi, I., King, D., and D.
              Ceccarelli, "Applicability of Abstraction and Control of
              Traffic Engineered Networks (ACTN) to Packet Optical
              Integration (POI)", Work in Progress, Internet-Draft,
              draft-ietf-teas-actn-poi-applicability-04, 17 January
              2022, <https://www.ietf.org/archive/id/draft-ietf-teas-
              actn-poi-applicability-04.txt>.

   [ONF_TR-547]
              Open Networking Foundation (ONF), "TAPI v2.1.3 Reference
              Implementation Agreement", ONF TR-547 TAPI RIA v1.0 , July
              2020, <https://opennetworking.org/wp-
              content/uploads/2020/08/TR-547-TAPI-v2.1.3-Reference-
              Implementation-Agreement-1.pdf>.

   [RFC8345]  Clemm, A., Medved, J., Varga, R., Bahadur, N.,
              Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
              Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
              2018, <https://www.rfc-editor.org/info/rfc8345>.

Acknowledgments

   The authors of this document would like to thank the authors of
   [I-D.ietf-teas-actn-poi-applicability] for having identified the gap
   and requirements to trigger this work.

   This document was prepared using kramdown.

Authors' Addresses

   Chaode Yu
   Huawei Technologies
   Email: yuchaode@huawei.com


   Italo Busi
   Huawei Technologies
   Email: italo.busi@huawei.com





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   Aihua Guo
   Futurewei Technologies
   Email: aihuaguo.ietf@gmail.com


   Sergio Belotti
   Nokia
   Email: sergio.belotti@nokia.com


   Jean-Francois Bouquier
   Vodafone
   Email: jeff.bouquier@vodafone.com


   Fabio Peruzzini
   TIM
   Email: fabio.peruzzini@telecomitalia.it


   Oscar Gonzalez de Dios
   Telefonica
   Email: oscar.gonzalezdedios@telefonica.com


   Victor Lopez
   Nokia
   Email: victor.lopez@nokia.com























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