A YANG Data Model for Passive Network Inventory
draft-ygb-ivy-passive-network-inventory-01

IVY Working Group                                                  C. Yu
Internet-Draft                                                    Huawei
Intended status: Standards Track                                  A. Guo
Expires: 5 January 2026                                        Futurewei
                                                                 I. Busi
                                                                  Huawei
                                                               M. Boroon
                                                              Highstreet
                                                              S. Belotti
                                                           T.V. Caenegem
                                                                 S.1. S.
                                                                   S. B.
                                                                   Nokia
                                                                N. Davis
                                                                   Ciena
                                                              M. Tilocca
                                                                FiberCop
                                                               B. Peters
                                                                     NBN
                                                                B.Y. Yun
                                                                    ETRI
                                                                  Y. Liu
                                                                 Y. Zhao
                                                            China Mobile
                                                       A. Sakalabhaktula
                                                                 Radisys
                                                             4 July 2025

            A YANG Data Model for Passive Network Inventory
               draft-ygb-ivy-passive-network-inventory-01

Abstract

   This document presents a YANG data model for tracking and managing
   passive network inventory.  The model enhances the base model
   outlined in [I-D.draft-ietf-ivy-network-inventory-yang] and is
   intended for use in the northbound interface of a domain controller
   as defined in [RFC8453].

Status of This Memo

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

Yu, et al.               Expires 5 January 2026                 [Page 1]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   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 5 January 2026.

Copyright Notice

   Copyright (c) 2025 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 . . . . . . . . . . . .   3
     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
   3.  Terminology and Notations . . . . . . . . . . . . . . . . . .   6
     3.1.  Requirements Notations  . . . . . . . . . . . . . . . . .   6
     3.2.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   6
     3.3.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   7
     3.4.  Prefixes in Data Node Names . . . . . . . . . . . . . . .   8
   4.  Modeling Considerations . . . . . . . . . . . . . . . . . . .   8
     4.1.  Relationship with Network Inventory . . . . . . . . . . .   8
     4.2.  Relationship with Topology  . . . . . . . . . . . . . . .   8
   5.  YANG Model Overview . . . . . . . . . . . . . . . . . . . . .   8
   6.  Model Tree Diagram  . . . . . . . . . . . . . . . . . . . . .   8
   7.  YANG Modules  . . . . . . . . . . . . . . . . . . . . . . . .  10
     7.1.  YANG Data Model for Passive Device Inventory  . . . . . .  10
   8.  Manageability Considerations  . . . . . . . . . . . . . . . .  21
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  21
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  22

Yu, et al.               Expires 5 January 2026                 [Page 2]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   11. Normative References  . . . . . . . . . . . . . . . . . . . .  22
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  24

1.  Introduction

   Passive infrastructure refers to the underlying infrastructure of a
   telecommunication network that is not actively detectable or
   managable.  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.

   [I-D.draft-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.draft-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.draft-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.

Yu, et al.               Expires 5 January 2026                 [Page 3]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

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.

   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

Yu, et al.               Expires 5 January 2026                 [Page 4]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

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.

   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

Yu, et al.               Expires 5 January 2026                 [Page 5]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

        Figure 2: Passive Infrastructure for Optical Access Networks

2.3.  Passive Infrastructure in Microwave Networks

   To be developed.

3.  Terminology and Notations

3.1.  Requirements Notations

   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.

3.2.  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.

Yu, et al.               Expires 5 January 2026                 [Page 6]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   *  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.draft-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.

3.3.  Tree Diagram

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

Yu, et al.               Expires 5 January 2026                 [Page 7]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

3.4.  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 | RFC XXXX  |
              +--------+------------------------+-----------+
              | nil    | ietf-ni-location       | RFC YYYY  |
              +--------+------------------------+-----------+

                  Table 1: Prefixes and Corresponding YANG
                                  Modules

   RFC Editor Note: Please replace XXXX with the RFC number assigned to
   [I-D.draft-ietf-ivy-network-inventory-yang].  Please replace YYYY
   with the RFC number assigned to
   [I-D.draft-ietf-ivy-network-inventory-location].  Please remove this
   note.

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.draft-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.  Model Tree Diagram

Yu, et al.               Expires 5 January 2026                 [Page 8]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   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)

Yu, et al.               Expires 5 January 2026                 [Page 9]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

       |           |  +--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

            Figure 3: Tree diagram for passive network inventory

7.  YANG Modules

7.1.  YANG Data Model for Passive Device Inventory

   <CODE BEGINS> file "ietf-nwi-passive-inventory@2025-06-30.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
       "RFCXXXX: A YANG Data Model for Network Inventory";
       //RFC Editor: replace XXXX with actual RFC number
       //and remove this note
     }
     import ietf-ni-location {
       prefix nil;
       reference
       "RFCYYYY: A YANG Data Model for Network Inventory Location";
       //RFC Editor: replace YYYY with actual RFC number
       //and remove this note
     }

Yu, et al.               Expires 5 January 2026                [Page 10]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

     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.

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

       Copyright (c) 2023 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.

       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 2024-10-21 {

Yu, et al.               Expires 5 January 2026                [Page 11]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

       description
         "Initial version";
       reference
         "RFC XXXX: A YANG Data Model for Passive Device Info in
          Network Inventory.";
         //RFC Editor: replace XXXX with actual RFC number, update date
         //information and remove this note
     }

     /* 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
         "ITU-T G.654 fiber.";
     }
     identity G655 {
       base fiber-type;
       description
         "ITU-T G.655 fiber.";

Yu, et al.               Expires 5 January 2026                [Page 12]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

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

     identity cable-role {

Yu, et al.               Expires 5 January 2026                [Page 13]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

       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.";
     }
     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.";
     }

Yu, et al.               Expires 5 January 2026                [Page 14]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

     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;
       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

Yu, et al.               Expires 5 January 2026                [Page 15]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

         "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;
         }
         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()/.."

Yu, et al.               Expires 5 January 2026                [Page 16]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

                  + "/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
           "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.";
       }

Yu, et al.               Expires 5 January 2026                [Page 17]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

       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.";
         }
         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:common-entity-attributes;

       leaf cable-type {
         type identityref {
           base cable-type;

Yu, et al.               Expires 5 January 2026                [Page 18]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

         }
         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.";
         }

         uses common-cable-attributes;
       }
     }

     grouping cables {
       description
         "Attributes applicable to cables.";

       list cable {
         key "id";
         description
           "List of cables.";

         uses cable-attributes;

Yu, et al.               Expires 5 January 2026                [Page 19]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

         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: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 {
         key "id";
         description
           "List of passive devices.";

         leaf id {
           type string;
           description
             "Cable identifier.";
         }

Yu, et al.               Expires 5 January 2026                [Page 20]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

         uses nwi: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 4: YANG model for passive network inventory

8.  Manageability Considerations

   TBD.

9.  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

Yu, et al.               Expires 5 January 2026                [Page 21]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   [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.

10.  IANA Considerations

   It is proposed to IANA to assign new URIs from the "IETF XML
   Registry" [RFC3688] as follows:

      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.

   This document registers the following YANG module in the YANG Module
   Names registry [RFC6020].

      name: ietf-nwi-passive-inventory
      namespace: urn:ietf:params:xml:ns:yang:ietf-nwi-passive-inventory
      prefix: nwi-passive
      reference: RFC XXXX

11.  Normative References

Yu, et al.               Expires 5 January 2026                [Page 22]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   [I-D.draft-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-01, 17 April 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-ivy-
              network-inventory-location-01>.

   [I-D.draft-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-06, 21 May 2025,
              <https://datatracker.ietf.org/doc/html/draft-ietf-ivy-
              network-inventory-yang-06>.

   [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>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/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/info/rfc6020>.

   [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>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/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/info/rfc7950>.

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

Yu, et al.               Expires 5 January 2026                [Page 23]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   [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>.

   [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/info/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/info/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/info/rfc8446>.

   [RFC8453]  Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
              Abstraction and Control of TE Networks (ACTN)", RFC 8453,
              DOI 10.17487/RFC8453, August 2018,
              <https://www.rfc-editor.org/info/rfc8453>.

   [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/info/rfc8795>.

Authors' Addresses

   Chaode Yu
   Huawei
   Email: yuchaode@huawei.com

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

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

Yu, et al.               Expires 5 January 2026                [Page 24]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

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

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

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

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

   Swaminathan B.
   Nokia
   Email: swaminathan.b@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

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

   Yucong Liu
   China Mobile
   Email: liuyucongyjy@chinamobile.com

Yu, et al.               Expires 5 January 2026                [Page 25]
Internet-Draft    Passive Network Inventory YANG Model         July 2025

   Yang Zhao
   China Mobile
   Email: zhaoyangyjy@chinamobile.com

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

Yu, et al.               Expires 5 January 2026                [Page 26]