



Network Inventory YANG                                            A. Guo
Internet-Draft                                                 Futurewei
Intended status: Standards Track                          T. V. Caenegem
Expires: 27 November 2026                                          Nokia
                                                                N. Davis
                                                                   Ciena
                                                              M. Tilocca
                                                                FiberCop
                                                               B. Peters
                                                                     NBN
                                                             26 May 2026


            A YANG Data Model for Passive Network Inventory
               draft-ygb-ivy-passive-network-inventory-05

Abstract

   This document presents a YANG data model for tracking and managing
   passive network inventory.  The model augments the base network
   inventory model.

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://aguoietf.github.io/draft-ygb-ivy-passive-network-inventory/
   draft-ygb-ivy-passive-network-inventory.html.  Status information for
   this document may be found at https://datatracker.ietf.org/doc/draft-
   ygb-ivy-passive-network-inventory/.

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

   Source for this draft and an issue tracker can be found at
   https://github.com/aguoietf/draft-ygb-ivy-passive-network-inventory.

Status of This Memo

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







Guo, et al.             Expires 27 November 2026                [Page 1]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   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/.

   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 27 November 2026.

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
   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  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Examples of Passive Network Inventory . . . . . . . . . . . .   4
     2.1.  Passive Infrastructure in Optical Transport Networks  . .   4
     2.2.  Passive Infrastructure in Optical Access Networks . . . .   5
     2.3.  Passive Infrastructure in Microwave Networks  . . . . . .   6
     2.4.  Editorial Note (To be removed by RFC Editor)  . . . . . .   6
   3.  Terminology and Notations . . . . . . . . . . . . . . . . . .   7
     3.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   7
     3.2.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   8
     3.3.  Prefixes in Data Node Names . . . . . . . . . . . . . . .   9
   4.  Modeling Considerations . . . . . . . . . . . . . . . . . . .   9
     4.1.  Relationship with Network Inventory . . . . . . . . . . .   9
     4.2.  Relationship with Topology  . . . . . . . . . . . . . . .   9
   5.  YANG Model Overview . . . . . . . . . . . . . . . . . . . . .   9
   6.  YANG Modules  . . . . . . . . . . . . . . . . . . . . . . . .   9
     6.1.  YANG Data Model for Passive Device Inventory  . . . . . .   9
   7.  Operational Considerations  . . . . . . . . . . . . . . . . .  21
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  21
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  21
   10. References  . . . . . . . . . . . . . . . . . . . . . . . . .  22



Guo, et al.             Expires 27 November 2026                [Page 2]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


     10.1.  Normative References . . . . . . . . . . . . . . . . . .  22
     10.2.  Informative References . . . . . . . . . . . . . . . . .  23
   Appendix A.  The Complete Schema Trees  . . . . . . . . . . . . .  23
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  29
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  29
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  30

1.  Introduction

   Passive infrastructure refers to the underlying infrastructure of a
   telecommunication network that is not actively detectable or
   manageable.  It typically includes non-powered, non-communicating
   devices and components, such as cabinets, cables, connectors,
   splitters, antennas, distribution frames, etc., that are either
   hosted within an actively managed device or deployed along the
   physical pathway between active devices.  Passive infrastructure
   serves as physical connections between active network devices,
   forming the backbone for network topology.  As a crucial part of
   communication networks,the inventory information for these devices is
   also essential for inventory management.

   Passive inventory contains a collection of inventory objects
   pertaining to the physical network infrastructure that are not
   powered and may have no direct management communication, and that are
   used to realize the underlying physical infrastructure carrying
   signals through a network.  Passive inventory includes elements such
   as optical cables, fiber segments, splice points, closures, ducts,
   and supporting structures that do not perform active processing,
   forwarding, or control functions.  These objects are maintained for
   purposes such as identification, location, connectivity, and
   lifecycle management.

   While passive inventory generally refers to non-powered
   infrastructure with no direct management communication, certain
   exceptions exist within the scope of passive inventory with respect
   to these characteristics.  Following are a non-exhausive list of
   exceptions:

   *  Fibers used in Raman amplification, where the fiber itself
      participates in amplification stimulated by an externally supplied
      pump laser.  In this scenario, the fiber is still considered as a
      passive element.

   *  Passive optical components embedded within an active device, such
      as an optical splitter located inside a managed network element.






Guo, et al.             Expires 27 November 2026                [Page 3]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   *  Fibers or other passive elements that are not currently lit or
      carrying traffic, but are still part of the physical
      infrastructure and require inventory representation.

   *  Passive devices that may have auxiliary or incidental powering
      (e.g., for environmental monitoring or enclosure heating) but do
      not perform active forwarding, processing, or control functions.
      [I-D.ietf-ivy-network-inventory-yang] incorporates the component
      concept from [RFC8348] to detail the equipment and holder
      information of a NE.  This encompasses chassis, slot/sub-slot,
      board/sub-board, port, and transceiver.  As these items are
      recognized by the NE through internal protocols, the passive
      devices that cannot be discovered by the NE are thus not included
      in the modeling and needs to be addressed.

   [I-D.ietf-ivy-network-inventory-location] emphasizes the relative and
   geographic location, e.g. equipment room, geo-loation for NE.  A
   passive device is deployed in a certain location visible by the
   operator, and thus can reference the location defined by
   [I-D.ietf-ivy-network-inventory-location].

   This document focuses on modeling passive device inventory.  The
   scope of this model is intended to be applicable to a varity types of
   networks, including but not limited to, IP/MPLS, optical access,
   optical transport and microwave networks.  The methods for learning
   about these devices are implementation-specific and fall outside the
   scope of this document.

2.  Examples of Passive Network Inventory

   Network segments built on different technologies share many common
   passive infrastructure components across the system.  To explore the
   practical applications of these components, we can examine example
   scenarios for optical access networks, optical transport systems, and
   microwave networks.

2.1.  Passive Infrastructure in Optical Transport Networks

   Passive infrastructure in optical transport networks serves as the
   backbone for high-capacity data transmission.  Key components include
   fiber optic cables, which act as the primary medium of long distance
   transmission.  Optical connectors, patch panels, and splice
   enclosures are crucial for joining and managing fiber links.
   Couplers and splitters are used for signal distribution and
   combining.






Guo, et al.             Expires 27 November 2026                [Page 4]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   Within a phyical network element (NE) there are also presence of
   passive components.  For example, fiber optic cables are used to
   connect the ports of different modules within the same or between
   different chassises.  Attenuators, on the other hand, are placed at
   places through connectors or built-in modules for reducing optical
   power.

   Figure 1 illustrates a typical passive infrastructure for a point-to-
   point optical transport network.

                                    Port
  +--------------+                  +-+                 +--------------+
  | +---+        |            +-----+ +----+            |        +---+ |
  | |  +++       |<--Cable--->|     +-+    |<--Cable--->|       +++  | |
  | |  ++* +---+ |            |    /   \   |            | +---+ *++  | |
  | |NE |\+++  | |Cable- Cable|  /      \  |Cable- Cable| |  +++/| NE| |
  | +---+ *++ +++|<-->| |<-->+++/        \+++<->| |<--->|+++ ++* +---+ |
  |        |  + +|----| |----+ |----------| +---| |-----|+ +  |        |
  |       +++ +++|----| |----+++\        /+++---| |-----|+++ +++       |
  | +---+/*++  | |     -      |  \      /  |     -      | |  ++*\+---+ |
  | |  +*+ |ODF| |    Joint   |   \    /   |    Joint   | |ODF| +*+  | |
  | |  +++ +---+ |    Box     |    \  /    |    Box     | +---+ +++  | |
  | |NE |        |            |     *-+    |            |        | NE| |
  | +---+        |            +-----+ +----+            |        +---+ |
  |Central Office|                  +-+                 |Central Office|
  +--------------+              Fiber                   +--------------+
                                Distribution
                                Terminal

     Figure 1: Passive Infrastructure for Optical Transport Networks

2.2.  Passive Infrastructure in Optical Access Networks

   Passive Optical Networks (PONs) are a typical type of optical access
   network with significant passive infrastructure.  The passive
   infrastructure in PON, often referred to as Optical Distribution
   Network (ODN), is the physical optical fiber-based network that
   connects the Optical Line Terminal (OLT) typically hosted in a
   central office to the Optical Network Unit/Terminal (ONU/ONT)
   typically deployed at the user's location.  The ODN is equipped with
   one or multiple cascaded passive optical splitter thus creating a
   physical point-to-multipoint fiber network between an OLT port and
   the multiple connected ONU/ONTs.








Guo, et al.             Expires 27 November 2026                [Page 5]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   The feeder segment of an ODN refers to the cabling between the OLT
   and the first splitter, whereas the distribution segment of the ODN
   comprises the fiber cabling between the first and second splitter
   stage.  The drop segment comprises the drop fibers between the ONT/
   ONU and the second splitter stage.

   The PON ODN hence comprises optical fiber cables and splitters but
   also many auxiliary components, such as connectors, fiber
   distribution terminals (FDT), fiber access terminals (FAT),
   wavelength co-existence elements, etc.  The passive components where
   the optical signals entering or leaving the optical fibers are split/
   combined or cross-connected are typically hosted in mini cabinets
   e.g. at street corners, manholes, attached to utility poles, etc.

   Figure 2 illustrates a typical passive infrastructure for optical
   access networks.

   +--------------+                                    <--Drop-->
   | +---+        |                                       Cable
   | |  +++       |<-Feeder Cable->    <--Distr.-->  /|----------+-+ONU
   | |  ++* +---+ |                       Cable     / |          +-+
   | |NE |\+++  | | Cable -  Cable   /|------------x  |FDT
   | +---+ *++ +++|<---->/ \<---->  / |             \ |
   | (OLT)  |  + +|------| |------x/  |              \|----------+-+ONU
   |       +++ +++|------| |------x   | cccccccc                 +-+
   | +---+/*++  | |      \ /       \  | c   /| c
   | |  +*+ |ODF| |       -         \ | c  / | c
   | |  +++ +---+ |     Joint        \|-c-x  | c
   | |NE |        |     Box        FDT  c  \ | c<---Drop Cable-->+-+ONU
   | +---+        |                     c   \|-c-----------------+-+
   | (OLT)        |                     c FDT <c
   |              |                     c      c
   |Central Office|                     cccccccc
   +--------------+                     Cabinet

        Figure 2: Passive Infrastructure for Optical Access Networks

2.3.  Passive Infrastructure in Microwave Networks

   To be developed.

2.4.  Editorial Note (To be removed by RFC Editor)

      Note to the RFC Editor: This section is to be removed prior to
      publication.






Guo, et al.             Expires 27 November 2026                [Page 6]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   This document contains placeholder values that need to be replaced
   with finalized values at the time of publication.  This note
   summarizes all of the substitutions that are needed.

   Please apply the following replacements:

   *  XXXX --> the assigned RFC number for this I-D

   *  YYYY --> the assigned RFC number for
      [I-D.ietf-ivy-network-inventory-yang]

   *  ZZZZ --> the assigned RFC number for
      [I-D.ietf-ivy-network-inventory-location]

   Please replace the revision date of the latest revision of the 'ietf-
   nwi-passive-inventory' module with the publication date of this I-D,
   using the the format (year-month-day).

   Please manually fix the YANG trees in Appendix A which have been
   generated by pyang and have some bugs.

3.  Terminology and Notations

3.1.  Terminology

   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 following terms are defined and used in this document.





Guo, et al.             Expires 27 November 2026                [Page 7]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   *  Passive device: refers to a physical device within a network that
      does not require external power to function, and simply
      manipulates signals through processes like transmission,
      reflection, splitting, filtering, or attenuation without actively
      amplifying or generating the signal.  Examples include optical
      fibers, splitters, couplers, and optical filters, all of which are
      used to direct signals within a system without needing power.  A
      passive device typically does not have management interfaces and
      is typically deployed in a location tracked by the network
      operator.

   *  Active device: refers to a physical device that contains hardware
      and software and is managable through communication interfaces.
      Network elements defined by [I-D.ietf-ivy-network-inventory-yang]
      are examples of active device.

   *  Guiding media: refers to physical transmission pathways - such as
      optical fiber cables, electrical cables, and coaxial cables - that
      direct and confine electromagnetic signals along a specific route.
      These media provide a bounded channel for data transmission,
      ensuring signal integrity, minimizing interference, and enabling
      high-speed communication over varying distances.  This category is
      also commonly known as guided media or wired transmission media.
      Guiding media can be concatenated to form longer guiding media.

   *  Optical Cable: refers to a type of guiding media that uses optical
      fiber as media to transmit optical signals.  An optical cable can
      contain one or multiple fiber cores, also known as fiber strands,
      each serving as an independent guiding media for data
      transmission.  Optical cables can be spliced or fused through
      joint boxes, optical distribution frames (ODF), or fiber jumpers.

   *  Electrical Cable: refers to a type of guiding media that uses
      metal conductors (such as copper or aluminum wires) as a medium to
      carry electrical signals for communication or power distribution.
      Common examples include twisted-pair cables (such as CAT-5/6 and
      DSL cables), and coaxial cables, which feature a single-core
      conductor commonly used in DOCSIS and MoCA-based broadband access
      networks.  Electrical cables can be connected through splicing,
      connectors, or junction boxes.

3.2.  Tree Diagram

   Tree diagrams used in this document follow the notation defined in
   [RFC8340].






Guo, et al.             Expires 27 November 2026                [Page 8]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


3.3.  Prefixes 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 Table 1.

             +==========+========================+===========+
             | Prefix   | YANG module            | Reference |
             +==========+========================+===========+
             | nwi      | ietf-network-inventory | [RFCYYYY] |
             +----------+------------------------+-----------+
             | nil      | ietf-ni-location       | [RFCZZZZ] |
             +----------+------------------------+-----------+
             | l0-types | ietf-layer0-types      | RFC XXXX  |
             +----------+------------------------+-----------+

              Table 1: Prefixes and corresponding YANG module

4.  Modeling Considerations

4.1.  Relationship with Network Inventory

   TBD

4.2.  Relationship with Topology

   TBD

5.  YANG Model Overview

   The YANG data model in this draft augments the model defined in
   [I-D.ietf-ivy-network-inventory-yang] with the following information:

   *  Passive devices: a list of passive devices with extended
      attributed reported by the domain controller.

   *  Cables: a list of cables with each containing an optional list of
      child cables.

6.  YANG Modules

6.1.  YANG Data Model for Passive Device Inventory









Guo, et al.             Expires 27 November 2026                [Page 9]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   <CODE BEGINS> file "ietf-nwi-passive-inventory@2026-03-19.yang"
   module ietf-nwi-passive-inventory {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-nwi-passive-inventory";
     prefix nwi-passive;

     import ietf-network-inventory {
       prefix nwi;
       reference
         "RFC YYYY: A YANG Data Model for Network Inventory";
     }
     import ietf-ni-location {
       prefix nil;
       reference
         "RFC ZZZZ: A YANG Data Model for Network Inventory Location";
     }

     organization
       "IETF Network Inventory YANG (IVY) Working Group";
     contact
       "WG Web:   <https://datatracker.ietf.org/wg/ivy/>
        WG List:  <mailto:inventory-yang@ietf.org>

        Editor:   Chaode Yu
                  <yuchaode@huawei.com>

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

        Editor:   Italo Busi
                  <italo.busi@huawei.com>";
     description
       "This YANG module specifies a data model for passive
        devices, such as fibers, cables, and passive sites,
        deployed within and between network elements.

        Copyright (c) 2026 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 Revised 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).

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



Guo, et al.             Expires 27 November 2026               [Page 10]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


     revision 2026-03-19 {
       description
         "Initial version";
       reference
         "RFC XXXX: A YANG Data Model for Passive Device Info in
                    Network Inventory.";
     }

     /* Identities */

     identity fiber-type {
       description
         "Base identity for fiber types.";
     }

     identity G652A {
       base fiber-type;
       description
         "ITU-T G.652A fiber.";
     }

     identity G652B {
       base fiber-type;
       description
         "ITU-T G.652B fiber.";
     }

     identity G652C {
       base fiber-type;
       description
         "ITU-T G.652C fiber.";
     }

     identity G652D {
       base fiber-type;
       description
         "ITU-T G.652D fiber.";
     }

     identity G653 {
       base fiber-type;
       description
         "ITU-T G.653 fiber.";
     }

     identity G654 {
       base fiber-type;
       description



Guo, et al.             Expires 27 November 2026               [Page 11]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


         "ITU-T G.654 fiber.";
     }

     identity G655 {
       base fiber-type;
       description
         "ITU-T G.655 fiber.";
     }

     identity G656 {
       base fiber-type;
       description
         "ITU-T G.656 fiber.";
     }

     identity G657A1 {
       base fiber-type;
       description
         "ITU-T G.657A1 fiber.";
     }

     identity G657A2 {
       base fiber-type;
       description
         "ITU-T G.657A2 fiber.";
     }

     identity G657B {
       base fiber-type;
       description
         "ITU-T G.657B fiber.";
     }

     identity other {
       base fiber-type;
       description
         "Other type of fiber.";
     }

     identity cable-type {
       description
         "Base identity for cable types.";
     }

     identity optical-fiber {
       base cable-type;
       description
         "Fiber optic cable.";



Guo, et al.             Expires 27 November 2026               [Page 12]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


     }

     identity electrical-cable {
       base cable-type;
       description
         "Electrical cable.";
     }

     identity coaxial-cable {
       base electrical-cable;
       description
         "Coaxial cable.";
     }

     identity cable-role {
       description
         "Base identity for cable roles.";
     }

     identity backbone {
       base cable-role;
       description
         "Backbone cable.";
     }

     identity aggregation {
       base cable-role;
       description
         "Aggregation cable.";
     }

     identity access {
       base cable-role;
       description
         "Access cable.";
     }

     identity trunk {
       base cable-role;
       description
         "Trunk cable.";
     }

     identity distribution {
       base cable-role;
       description
         "Distribution cable.";
     }



Guo, et al.             Expires 27 November 2026               [Page 13]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


     identity branch {
       base cable-role;
       description
         "Branch cable.";
     }

     identity passive-port-type {
       description
         "Base identity for passive port types.";
     }

     identity service-port {
       base passive-port-type;
       description
         "Service port.";
     }

     identity input-port {
       base passive-port-type;
       description
         "Input port.";
     }

     identity output-port {
       base passive-port-type;
       description
         "Output port.";
     }

     identity p2mp-port {
       base passive-port-type;
       description
         "Input port.";
     }

     identity connected-device-type {
       description
         "Base identity for connected device types.";
     }

     identity passive-device {
       base connected-device-type;
       description
         "Passive/unmanaged device.";
     }

     identity active-device {
       base connected-device-type;



Guo, et al.             Expires 27 November 2026               [Page 14]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


       description
         "Active device, e.g. network element.";
     }

     identity passive-device-type {
       description
         "Base identity for passive device types.";
     }

     identity ODF {
       base passive-device-type;
       description
         "Optical Distribution Frame.";
     }

     identity WDM {
       base passive-device-type;
       description
         "Wavelength Division Multiplexer.";
     }

     identity FAT {
       base passive-device-type;
       description
         "Fiber Access Terminal.";
     }

     identity FDT {
       base passive-device-type;
       description
         "Fiber Distribution Terminal.";
     }

     identity ATB {
       base passive-device-type;
       description
         "Access Terminal Box.";
     }

     /* Groupings */

     grouping connected-device-end {
       description
         "Attributes applicable to connected device end.";
       leaf device-type {
         type identityref {
           base connected-device-type;
         }



Guo, et al.             Expires 27 November 2026               [Page 15]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


         description
           "Type of connected device.";
       }
       choice connected-device-type {
         description
           "Device end based on the type of connected device.";
         case passive {
           leaf device-id {
             type string;
             must "derived-from-or-self(../device-type,
                   'nwi-passive:passive-device')";
             description
               "Connected passive device identifier.";
           }
         }
         case active {
           leaf ne-ref {
             type leafref {
               path "/nwi:network-inventory/nwi:network-elements"
                  + "/nwi:network-element/nwi:ne-id";
             }
             must "derived-from-or-self(../device-type,
                   'nwi-passive:active-device')";
             description
               "Referenced Network Element (NE).";
           }
           leaf component-ref {
             type leafref {
               path "/nwi:network-inventory/nwi:network-elements"
                  + "/nwi:network-element[nwi:ne-id=current()/.."
                  + "/ne-ref]/nwi:components/nwi:component"
                  + "/nwi:component-id";
             }
             must "derived-from-or-self(../device-type,
                   'nwi-passive:active-device')";
             description
               "Referenced connected active device's component,
                e.g. port component.";
           }
         }
       }
     }

     grouping connected-device-ref {
       description
         "Attributes applicable to connected devices.";
       container a-end {
         description



Guo, et al.             Expires 27 November 2026               [Page 16]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


           "A-end device reference";
         uses connected-device-end;
       }
       container z-end {
         description
           "Z-end device reference";
         uses connected-device-end;
       }
     }

     grouping common-cable-attributes {
       description
         "Common attributes of cables applicable to the cable
          and its child cables.";
       leaf id {
         type string;
         description
           "Cable identifier.";
       }
       leaf length {
         type uint32;
         units "meter";
         description
           "Length of the cable in meter.";
       }
       uses connected-device-ref;
     }

     grouping optical-cable-attributes {
       description
         "Attributes applicable to fiber optic cables.";
       container optical-cable {
         when "derived-from-or-self(../cable-type, 'optical-fiber')";
         description
           "Container for attributes associated with fiber
            optic cables.";
         leaf fiber-core-num {
           type uint32;
           description
             "Number of fiber cores within the cable.";
         }
         leaf fiber-type {
           type identityref {
             base fiber-type;
           }
           description
             "Type of fiber contained in the cable.";
         }



Guo, et al.             Expires 27 November 2026               [Page 17]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


         leaf attenuation {
           type decimal64 {
             fraction-digits 2;
           }
           units "dB";
           description
             "The fiber attenuation in dB.";
         }
       }
     }

     grouping cable-attributes {
       description
         "Attributes of cables.";
       uses common-cable-attributes;
       uses nwi:basic-common-entity-attributes;
       leaf cable-type {
         type identityref {
           base cable-type;
         }
         description
           "Type of cable.";
       }
       leaf cable-role {
         type identityref {
           base cable-role;
         }
         description
           "Role of cable.";
       }
       uses optical-cable-attributes;
     }

     grouping child-cables {
       description
         "Attributes applicable to child cables that are concatnated
          to form the cable.";
       list child-cable {
         key "index";
         min-elements 2;
         description
           "Ordered list of concatenated child cables.";
         leaf index {
           type uint8;
           description
             "An index number used to identify the concatenation
              order of the child cables.";
         }



Guo, et al.             Expires 27 November 2026               [Page 18]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


         uses common-cable-attributes;
       }
     }

     grouping cables {
       description
         "Attributes applicable to cables.";
       list cable {
         key "id";
         description
           "List of cables.";
         uses cable-attributes;
         uses child-cables;
       }
     }

     grouping passive-device-ports {
       description
         "Attributes applicable to passive device ports.";
       list passive-port {
         key "id";
         description
           "List of ports on a passive device.";
         leaf id {
           type string;
           description
             "Port identifier.";
         }
         uses nwi:basic-common-entity-attributes;
         leaf port-type {
           type identityref {
             base passive-port-type;
           }
           description
             "Type of passive port.";
         }
         leaf fiber-core-num {
           type uint32;
           description
             "Number of fiber cores within the port.";
         }
       }
     }

     grouping passive-devices {
       description
         "Attributes applicable to passive devices.";
       list passive-device {



Guo, et al.             Expires 27 November 2026               [Page 19]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


         key "id";
         description
           "List of passive devices.";
         leaf id {
           type string;
           description
             "Cable identifier.";
         }
         uses nwi:basic-common-entity-attributes;
         leaf device-type {
           type identityref {
             base passive-device-type;
           }
           description
             "Type of passive device.";
         }
         leaf-list custom-tags {
           type string;
           description
             "Customized tags, e.g. RFID, QR code that are
              attached to the device.";
         }
         leaf location-ref {
           type nil:ni-location-ref;
           description
             "Referenced location for the passive device.";
         }
         uses passive-device-ports;
       }
     }

     /* Augmentation */

     augment "/nwi:network-inventory" {
       description
         "Augment network inventory with information
          for optical cables and passive devices.";
       uses cables;
       uses passive-devices;
     }
   }
   <CODE ENDS>

             Figure 3: YANG model for passive network inventory







Guo, et al.             Expires 27 November 2026               [Page 20]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


7.  Operational Considerations

   TBC per [I-D.opsarea-rfc5706bis].

8.  Security Considerations

   The YANG module specified in this document defines a schema for data
   that is designed to be accessed via network management protocols such
   as NETCONF [RFC6241] or RESTCONF [RFC8040].  The lowest NETCONF layer
   is the secure transport layer, and the mandatory-to-implement secure
   transport is Secure Shell (SSH) [RFC6242].  The lowest RESTCONF layer
   is HTTPS, and the mandatory-to-implement secure transport is TLS
   [RFC8446].

   The NETCONF access control model [RFC8341] provides the means to
   restrict access for particular NETCONF or RESTCONF users to a
   preconfigured subset of all available NETCONF or RESTCONF protocol
   operations and content.

   There are a number of data nodes defined in this YANG module that are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive or vulnerable
   in some network environments.  Write operations (e.g., edit-config)
   to these data nodes without proper protection can have a negative
   effect on network operations.  Considerations in Section 8 of
   [RFC8795] are also applicable to their subtrees in the module defined
   in this document.

   Some of the readable data nodes in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control read access (e.g., via get, get-config, or
   notification) to these data nodes.  Considerations in Section 8 of
   [RFC8795] are also applicable to their subtrees in the module defined
   in this document.

9.  IANA Considerations

   IANA is requested to register the following URI in the "ns" registry
   within the "IETF XML Registry" group [RFC3688]:

      URI: urn:ietf:params:xml:ns:yang:ietf-nwi-passive-inventory
      Registrant Contact: The IESG
      XML: N/A; the requested URI is an XML namespace.

   IANA is requested to register the following YANG module in the "YANG
   Module Names" registry [RFC6020] within the "YANG Parameters"
   registry group.




Guo, et al.             Expires 27 November 2026               [Page 21]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


      name: ietf-nwi-passive-inventory
      Maintained by IANA? N
      namespace: urn:ietf:params:xml:ns:yang:ietf-nwi-passive-inventory
      prefix: nwi-passive
      reference: RFC XXXX

10.  References

10.1.  Normative References

   [I-D.ietf-ivy-network-inventory-location]
              Wu, B., Belotti, S., Bouquier, J., Peruzzini, F., and P.
              Bedard, "A YANG Data Model for Network Inventory
              Location", Work in Progress, Internet-Draft, draft-ietf-
              ivy-network-inventory-location-05, 28 February 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-ivy-
              network-inventory-location-05>.

   [I-D.ietf-ivy-network-inventory-yang]
              Yu, C., Belotti, S., Bouquier, J., Peruzzini, F., and P.
              Bedard, "A Base YANG Data Model for Network Inventory",
              Work in Progress, Internet-Draft, draft-ietf-ivy-network-
              inventory-yang-17, 13 May 2026,
              <https://datatracker.ietf.org/doc/html/draft-ietf-ivy-
              network-inventory-yang-17>.

   [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/rfc/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/rfc/rfc6242>.

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

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/rfc/rfc8040>.

   [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/rfc/rfc8340>.





Guo, et al.             Expires 27 November 2026               [Page 22]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/rfc/rfc8341>.

   [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/rfc/rfc8348>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/rfc/rfc8446>.

   [RFC8795]  Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
              O. Gonzalez de Dios, "YANG Data Model for Traffic
              Engineering (TE) Topologies", RFC 8795,
              DOI 10.17487/RFC8795, August 2020,
              <https://www.rfc-editor.org/rfc/rfc8795>.

10.2.  Informative References

   [I-D.opsarea-rfc5706bis]
              Claise, B., Clarke, J., Farrel, A., Barguil, S.,
              Pignataro, C., and R. Chen, "Guidelines for Considering
              Operations and Management in IETF Specifications", Work in
              Progress, Internet-Draft, draft-opsarea-rfc5706bis-06, 20
              October 2025, <https://datatracker.ietf.org/doc/html/
              draft-opsarea-rfc5706bis-06>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/rfc/rfc3688>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/rfc/rfc6020>.

Appendix A.  The Complete Schema Trees

   This appendix presents the complete tree of the Passive Network
   Inventory data model.  See [RFC8340] for an explanation of the
   symbols used.  The data type of every leaf node is shown near the
   right end of the corresponding line.






Guo, et al.             Expires 27 November 2026               [Page 23]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   module: ietf-nwi-passive-inventory

     augment /nwi:network-inventory:
       +--rw cable* [id]
       |  +--rw id               string
       |  +--rw length?          uint32
       |  +--rw a-end
       |  |  +--rw device-type?           identityref
       |  |  +--rw (connected-device-type)?
       |  |     +--:(passive)
       |  |     |  +--rw device-id?       string
       |  |     +--:(active)
       |  |        +--rw ne-ref?          leafref
       |  |        +--rw component-ref?   leafref
       |  +--rw z-end
       |  |  +--rw device-type?           identityref
       |  |  +--rw (connected-device-type)?
       |  |     +--:(passive)
       |  |     |  +--rw device-id?       string
       |  |     +--:(active)
       |  |        +--rw ne-ref?          leafref
       |  |        +--rw component-ref?   leafref
       |  +--ro uuid?            yang:uuid
       |  +--rw name?            string
       |  +--rw description?     string
       |  +--rw alias?           string
       |  +--rw cable-type?      identityref
       |  +--rw cable-role?      identityref
       |  +--rw optical-cable
       |  |  +--rw fiber-core-num?   uint32
       |  |  +--rw fiber-type?       identityref
       |  |  +--rw attenuation?      decimal64
       |  +--rw child-cable* [index]
       |     +--rw index     uint8
       |     +--rw id?       string
       |     +--rw length?   uint32
       |     +--rw a-end
       |     |  +--rw device-type?           identityref
       |     |  +--rw (connected-device-type)?
       |     |     +--:(passive)
       |     |     |  +--rw device-id?       string
       |     |     +--:(active)
       |     |        +--rw ne-ref?          leafref
       |     |        +--rw component-ref?   leafref
       |     +--rw z-end
       |        +--rw device-type?           identityref
       |        +--rw (connected-device-type)?
       |           +--:(passive)



Guo, et al.             Expires 27 November 2026               [Page 24]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


       |           |  +--rw device-id?       string
       |           +--:(active)
       |              +--rw ne-ref?          leafref
       |              +--rw component-ref?   leafref
       +--rw passive-device* [id]
          +--rw id              string
          +--ro uuid?           yang:uuid
          +--rw name?           string
          +--rw description?    string
          +--rw alias?          string
          +--rw device-type?    identityref
          +--rw custom-tags*    string
          +--rw location-ref?   nil:ni-location-ref
          +--rw passive-port* [id]
             +--rw id                string
             +--ro uuid?             yang:uuid
             +--rw name?             string
             +--rw description?      string
             +--rw alias?            string
             +--rw port-type?        identityref
             +--rw fiber-core-num?   uint32

     grouping connected-device-end:
       +-- device-type?           identityref
       +-- (connected-device-type)?
          +--:(passive)
          |  +-- device-id?       string
          +--:(active)
             +-- ne-ref?          leafref
             +-- component-ref?   leafref
     grouping connected-device-ref:
       +-- a-end
       |  +-- device-type?           identityref
       |  +-- (connected-device-type)?
       |     +--:(passive)
       |     |  +-- device-id?       string
       |     +--:(active)
       |        +-- ne-ref?          leafref
       |        +-- component-ref?   leafref
       +-- z-end
          +-- device-type?           identityref
          +-- (connected-device-type)?
             +--:(passive)
             |  +-- device-id?       string
             +--:(active)
                +-- ne-ref?          leafref
                +-- component-ref?   leafref
     grouping common-cable-attributes:



Guo, et al.             Expires 27 November 2026               [Page 25]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


       +-- id?       string
       +-- length?   uint32
       +-- a-end
       |  +-- device-type?           identityref
       |  +-- (connected-device-type)?
       |     +--:(passive)
       |     |  +-- device-id?       string
       |     +--:(active)
       |        +-- ne-ref?          leafref
       |        +-- component-ref?   leafref
       +-- z-end
          +-- device-type?           identityref
          +-- (connected-device-type)?
             +--:(passive)
             |  +-- device-id?       string
             +--:(active)
                +-- ne-ref?          leafref
                +-- component-ref?   leafref
     grouping optical-cable-attributes:
       +-- optical-cable
          +-- fiber-core-num?   uint32
          +-- fiber-type?       identityref
          +-- attenuation?      decimal64
     grouping cable-attributes:
       +-- id?              string
       +-- length?          uint32
       +-- a-end
       |  +-- device-type?           identityref
       |  +-- (connected-device-type)?
       |     +--:(passive)
       |     |  +-- device-id?       string
       |     +--:(active)
       |        +-- ne-ref?          leafref
       |        +-- component-ref?   leafref
       +-- z-end
       |  +-- device-type?           identityref
       |  +-- (connected-device-type)?
       |     +--:(passive)
       |     |  +-- device-id?       string
       |     +--:(active)
       |        +-- ne-ref?          leafref
       |        +-- component-ref?   leafref
       +--ro uuid?            yang:uuid
       +-- name?            string
       +-- description?     string
       +-- alias?           string
       +-- cable-type?      identityref
       +-- cable-role?      identityref



Guo, et al.             Expires 27 November 2026               [Page 26]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


       +-- optical-cable
          +-- fiber-core-num?   uint32
          +-- fiber-type?       identityref
          +-- attenuation?      decimal64
     grouping child-cables:
       +-- child-cable* [index]
          +-- index     uint8
          +-- id?       string
          +-- length?   uint32
          +-- a-end
          |  +-- device-type?           identityref
          |  +-- (connected-device-type)?
          |     +--:(passive)
          |     |  +-- device-id?       string
          |     +--:(active)
          |        +-- ne-ref?          leafref
          |        +-- component-ref?   leafref
          +-- z-end
             +-- device-type?           identityref
             +-- (connected-device-type)?
                +--:(passive)
                |  +-- device-id?       string
                +--:(active)
                   +-- ne-ref?          leafref
                   +-- component-ref?   leafref
     grouping cables:
       +-- cable* [id]
          +-- id?              string
          +-- length?          uint32
          +-- a-end
          |  +-- device-type?           identityref
          |  +-- (connected-device-type)?
          |     +--:(passive)
          |     |  +-- device-id?       string
          |     +--:(active)
          |        +-- ne-ref?          leafref
          |        +-- component-ref?   leafref
          +-- z-end
          |  +-- device-type?           identityref
          |  +-- (connected-device-type)?
          |     +--:(passive)
          |     |  +-- device-id?       string
          |     +--:(active)
          |        +-- ne-ref?          leafref
          |        +-- component-ref?   leafref
          +--ro uuid?            yang:uuid
          +-- name?            string
          +-- description?     string



Guo, et al.             Expires 27 November 2026               [Page 27]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


          +-- alias?           string
          +-- cable-type?      identityref
          +-- cable-role?      identityref
          +-- optical-cable
          |  +-- fiber-core-num?   uint32
          |  +-- fiber-type?       identityref
          |  +-- attenuation?      decimal64
          +-- child-cable* [index]
             +-- index     uint8
             +-- id?       string
             +-- length?   uint32
             +-- a-end
             |  +-- device-type?           identityref
             |  +-- (connected-device-type)?
             |     +--:(passive)
             |     |  +-- device-id?       string
             |     +--:(active)
             |        +-- ne-ref?          leafref
             |        +-- component-ref?   leafref
             +-- z-end
                +-- device-type?           identityref
                +-- (connected-device-type)?
                   +--:(passive)
                   |  +-- device-id?       string
                   +--:(active)
                      +-- ne-ref?          leafref
                      +-- component-ref?   leafref
     grouping passive-device-ports:
       +-- passive-port* [id]
          +-- id                string
          +--ro uuid?             yang:uuid
          +-- name?             string
          +-- description?      string
          +-- alias?            string
          +-- port-type?        identityref
          +-- fiber-core-num?   uint32
     grouping passive-devices:
       +-- passive-device* [id]
          +-- id              string
          +--ro uuid?           yang:uuid
          +-- name?           string
          +-- description?    string
          +-- alias?          string
          +-- device-type?    identityref
          +-- custom-tags*    string
          +-- location-ref?   nil:ni-location-ref
          +-- passive-port* [id]
             +-- id                string



Guo, et al.             Expires 27 November 2026               [Page 28]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


             +--ro uuid?             yang:uuid
             +-- name?             string
             +-- description?      string
             +-- alias?            string
             +-- port-type?        identityref
             +-- fiber-core-num?   uint32

            Figure 4: Tree diagram for passive network inventory

Acknowledgments

   TODO acknowledge.

Contributors

   Chaode Yu
   Huawei
   Email: yuchaode@huawei.com


   Mohammad Boroon
   Highstreet
   Email: mohammad.boroon@highstreet-technologies.com


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


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


   Swaminathan 1. S.
   Nokia
   Email: swaminathan.1.s@nokia.com


   Swaminathan B.
   Nokia
   Email: swaminathan.b@nokia.com


   Bin Yu Yun
   ETRI
   Email: byyun@etri.re.kr



Guo, et al.             Expires 27 November 2026               [Page 29]

Internet-Draft    Passive Network Inventory YANG Model          May 2026


   Yucong Liu
   China Mobile
   Email: liuyucongyjy@chinamobile.com


   Yang Zhao
   China Mobile
   Email: zhaoyangyjy@chinamobile.com


   Avinash Sakalabhaktula
   Radisys
   Email: Avinash.Sakalabhaktula@radisys.com


Authors' Addresses

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


   Tom Van Caenegem
   Nokia
   Email: tom.van_caenegem@nokia.com


   Nigel Davis
   Ciena
   Email: ndavis@ciena.com


   Mauro Tilocca
   FiberCop
   Email: mauro.tilocca@fibercop.it


   Brad Peters
   NBN
   Email: bradpeters@nbnco.com.au











Guo, et al.             Expires 27 November 2026               [Page 30]
