]> Huawei Technologies

yuchaode@huawei.com

Nokia

s.belotti.ietf@gmail.com

Vodafone

jeff.bouquier@vodafone.com

FiberCop

fabio.peruzzini@fibercop.com

Cisco

phbedard@cisco.com

Operations and Management IVY Working Group next generation unicorn sparkling distributed ledger This document defines a base YANG data model for reporting network inventory. The scope of this base model is set to be application- and technology-agnostic. The base data model can be augmented with application- and technology-specific details. About This Document The latest revision of this draft can be found at . Status information for this document may be found at . Source for this draft and an issue tracker can be found at .

Introduction This document defines a base YANG data model for reporting network inventory that is application- and technology-agnostic. The base data model can be augmented to describe application- and technology-specific information. Please note that the usage of term "network inventory", in the context of this document, is to indicate that it is describing "network-wide" scope inventory information. Network inventory is a foundation for network management in all types of networks. Network operators need to keep a record of what equipment is planned and installed in their networks (including a variety of information such as product name, vendor, product series, embedded software, and hardware/software versions). Network inventories may be constructed from management system data to represent the expected devices present in the network, and also be used to audit and catalog what devices are discovered in the network, and to expose that information in a consistent way. Network inventory management is a critical component for ensuring the infrastructure remains up-to-date (e.g., identifying assets that need to be upgraded or decommissioned), stays healthy (e.g., auditing to identify faulty elements), and is maintained to meet strict performance objectives. Also, network inventory management allows operators to keep track of which devices are deployed in their networks, including relevant embedded software and hardware versions. Exposing standard interfaces to retrieve information relating to network element components as maintained in an inventory provides key enablers for many applications. For example, identifies a gap relating to the lack of YANG data models that could be used at Abstraction and Control of TE Networks (ACTN) Multi-Domain Service Coordinator-Provisioning Network Controller Interface (MPI) level to report whole or partial network hardware inventory information available at domain controller level towards upper layer systems (e.g., Multi-Domain Service Coordinator (MDSC) or Operations Support Systems (OSS) layers). defines a YANG data model for the management of the hardware on a single server and therefore it is more applicable to the domain controller towards the network elements rather than at the northbound interface of a network controller (e.g., toward an application or another hierarchical network controller). However, the YANG data model defined in has been used as a reference for defining the YANG network inventory data model presented in this document. Per the definition of and , the YANG data model defined in is a device model while the YANG data model defined in this document is a network model. As outlined in , the base network inventory model provides a read-only perspective of the installed network inventory data the controller is aware of. Therefore, other inventory data (e.g., inactive assets, warehouse spares, or planned assets) are outside the scope of this model. The distinction between a temporarily unreachable network element and one that has been removed from the network is outside the scope of this document and depends on the discovery mechanism used by the controller. As outlined in , the base inventory YANG data model defined in this document supports only physical network elements but generalizes the network element definition to allow supporting other types of network elements through proper augmentations. This document defines one YANG module "ietf-network-inventory" in . This base data model is application- and technology-agnostic (that is, valid for IP/MPLS, optical, and microwave networks as well as optical local loops, access networks, core networks, data centers, etc.) and can be augmented to include required application- and technology-specific inventory details together with specific hardware or software component's attributes. The YANG data model defined in the document is scoped to cover the common use cases for Inventory but at network-wide level, covering both hardware and base software information. The YANG data model defined in this document conforms to the Network Management Datastore Architecture .

Editorial Note (To be removed by RFC Editor)

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

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
• 2026-06-24 --> the actual date of the publication of this document

Terminology and Notations

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 when, and only when, they appear in all capitals, as shown here.

Terminology The following terms are defined in and are not redefined here:

• server
• augment
• data model
• data node

The following terms are defined in and are not redefined here:

• state data

The following terms are defined in and are not redefined here:

• Abstraction and Control of TE Networks (ACTN)
• Multi-Domain Service Coordinator (MDSC)
• Provisioning Network Controller (PNC)
• MDSC-PNC Interface (MPI)

The following terms are defined in the description statements of the corresponding YANG identities, defined in , and are not redefined here:

• backplane
• battery
• cpu
• fan
• module
• power supply
• sensor
• stack
• storage device

Also, the document makes use of the following terms:

Chassis:

A field replaceable equipment with a particular structural format and dimensions. A chassis can, but does not need to, include spaces (called slots) to take cards.

Elsewhere, a chassis can be called shelf, sub-rack, stand-alone unit, etc.

Port:

A component where networking traffic can be received and/or transmitted, e.g., by attaching networking cables.

In case of pluggable ports, the port may be empty when no pluggable module is plugged in.

Network Inventory:

A collection of data for network elements and their components with network-wide scope, managed by a specific management system.

Physical Network Element:

An implementation or application specific group of components (e.g., hardware components).

Network Element:

The generalization of the physical network element definition.

Hardware Component:

A general definition of category of components as defined in and (e.g., backplane, battery, container, central processing unit (CPU), chassis, fan, module, port, power supply, sensor, stack, and storage device components).

The list of hardware components can be extended in future versions of (and, consequently, of ().

Component:

A further extension of the hardware component definition to include other inventory objects which can be managed, from an inventory perspective, in the same way as hardware components.

Card:

Pluggable equipment with a particular structural format and dimensions which can be inserted into one or more slots (or sub-slots). A card can have spaces (called sub-slots) to take other cards.

Elsewhere, a card can be called board, module, circuit pack, etc..

Slot:

A space in a chassis that can be equipped with one card, which may be chosen from a limited range of types of cards. A slot can be subdivided into smaller spaces that can also be part of a Card (called sub-slots).

Container:

A hardware component class that is capable of containing one or more removable physical entities (e.g., a slot in a chassis is containing a board).

Tree Diagrams The meanings of the symbols in the YANG tree diagrams are defined in .

YANG Prefixes list the prefixes of the modules that are used in this document. Prefixes and corresponding YANG modules

Prefix	YANG Module	Reference
inet	ietf-inet-types
yang	ietf-yang-types
ianahw	iana-hardware
nwi	ietf-network-inventory	RFC XXXX

Artwork folding This document uses artwork folding for better formatting.

YANG Data Model for Network Inventory Overview The base network inventory model, defined in this document, provides a list of network elements and of network element components. The network-inventory top level container has been defined to support reporting other types of network inventory objects, besides the network elements and network element components. These additional types of network inventory objects can be defined, together with the associated YANG data model and the rationale for managing them as part of the network inventory, in other documents providing application- and technology-specific companion augmentation data models, such as . The network element definition is generalized to support physical network elements and other types of components' groups that can be managed as physical network elements from an inventory perspective. Physical network elements are usually devices such as hosts, gateways, terminal servers, and the like, which have management agents responsible for performing the network management functions requested by the network management stations (). The "ne-type" is defined as a YANG identity to describe the type of the network element. This document defines only the "physical-network-element" identity. Other types of network elements can be defined in other documents, together with the associated YANG identity and the rationale for managing them as network elements from an inventory perspective. The component definition is also generalized to support any types of component inventory objects that can be managed as hardware components from an inventory perspective. The data model for components defined in this document uses a list of components within each network element. Different types of components can be distinguished by the class of component. The component "class" is defined as a union between the hardware class identity, defined in "iana-hardware", and the "non-hardware" identity, defined in this document. Other types of components can be defined in other documents, together with the associated YANG identity and the rationale for managing them as components from an inventory perspective. The identity definition of additional types of "ne-type" and "non- hardware" identity of component are outside the scope of this document and could be defined in application- and technology-specific companion augmentation data models, such as . In , rack, chassis, slot, sub-slot, board and port are defined as components of network elements with generic attributes. While is used to manage the hardware of a single server (e.g., a network element), the Network Inventory YANG data model is used to retrieve the base inventory information that a controller discovers from all the network elements with network-wide scope under its control. However, the YANG data model defined in has been used as a reference for defining the YANG network inventory data model. This approach can simplify the implementation of this inventory model when the controller uses the YANG data model defined in to retrieve the hardware from the network elements under its control.

Common attributes for inventory object For all the inventory objects, there are some common attributes, including:

uuid:

The Universally Unique Identifier (UUID) of the inventory object, assigned by the server. Such identifiers are widely implemented with systems and guaranteed to be globally unique.

name:

A human-interpretable label of the inventory object, provided by a network operator or by the server. It could also be present on a Graphical User Interface (GUI).

alias:

A human-interpretable label of the inventory object, provided by a network operator. It could also be present on a GUI instead as well as the name.

description:

A human-interpretable description of the inventory object, provided by a network operator or by the server. The description provides more detailed information to prompt users when performing maintenance operations etc.

Common attributes for network elements and components To be consistent with the component definition, the following attributes defined in for components are reused for network elements:

mfg-name:

The name of the manufacturer of the entity (component or network element).

product-name:

The vendor-specific and human-interpretable string describing the entity (component or network element) type.

It is expected that vendors assign unique product names to different entities within the scope of the vendor.

Other software-related attributes are defined in and applicable to network elements and components.

Network Element In addition to the common attributes defined for network elements and components in , the following attributes are defined for the network elements:

ne-id:

The identifier that uniquely identifies the network element (NE) within the network, assigned by the server since the network elements cannot guarantee that their local identifier is unique within the network.

The ne-id should be assigned such that the same network element will always be identified through the same identifier, even if the network elements get disconnected from the network controller. Mechanisms to ensure this (e.g., checking the mfg-name, product-name, management IP address, physical location) are implementation specific and outside the scope of standardization.

ne-type:

The type of network element (e.g., physical network element). See for the definition of NE types.

product-rev:

A vendor-specific product revision string for the network-element.

Components The YANG data model for network inventory mainly follows the same approach as and reports the network hardware inventory as a list of components with different types (e.g., chassis, module, and port). In addition to the common attributes defined for network elements and components in , the following attributes are defined for the components:

component-id:

The identifier that uniquely identifies the component within the NE. It can be assigned by the NE or by the server.

class:

The type of component (e.g., chassis, module, port). See for the definition of component types.

hardware-rev:

The vendor-specific hardware revision string for the component.

The preferred value is the hardware revision identifier actually printed on the component itself (if present).

mfg-date:

The date of manufacturing of the component.

part-number:

The vendor-specific part number of the component type.

It is expected that vendors assign unique part numbers to different component types within the scope of the vendor.

• Although the part number is often an alphanumeric string and not a number, this document uses this term since it is widely used and well known in the industry.

serial-number:

The vendor-specific serial number of the component instance.

It is expected that vendors assign unique serial numbers to different component instances at least within the scope of the part-number.

• Although the serial number is often an alphanumeric string and not a number, this document uses this term since it is widely used and well known in the industry.

asset-id:

An asset tracking identifier for the component, provided by a network operator.

is-fru:

Indicates whether or not a component is considered a 'field-replaceable unit' by the vendor.

For state data like "admin-state", "oper-state", and so on, this document considers that they are related to device hardware management, not network inventory. Therefore, they are outside of the scope of this document. Same for the sensor-data, they should be defined in some other performance monitoring data models instead of the inventory data model.

Hardware Components Other models (e.g., ) classify the hardware components into two groups: holder group and equipment group. The holder group contains rack, chassis, slot, sub-slot while the equipment group contains network-element, board and port. This model, likewise , does not follow this classification and manages all the hardware components without distinguishing between holder and equipment groups. See , , and for concrete hardware component examples. describes the relationship between typical inventory objects in a physical network element.

Relationship between typical inventory objects in physical network elements | /sub-slot | | | +--------------+ +-----------+ || ||1:N \/ +-----------+ | port | +-----------+ ]]>

The "iana-hardware" module defines YANG identities for the hardware component types in the IANA-maintained "IANA-ENTITY-MIB" registry. Some of the definitions taken from are based on the ENTITY-MIB . Additional attributes of specific hardware, such as CPU, storage, port, or power supply are defined in the hardware extension.

Software Components Each instance of a network element or a component includes its own "software-rev" list which provides basic software attributes for each entity (network element and component). The scope of the list is to provide information about the software images that are running within the related entity. The term "running" here is intended as the software modules that the controller has discovered as running in the network element or component as explained in section . The way used by the controller to discover and keep synchronized running software information as well as manage transient state (e.g. reboot or loss of connectivity with the network element) is outside the scope of this document. The model supports scenarios where multiple software modules can be images running within the entity. For example, one Operating System and one or more Application software modules can be running in a network element, and, in the same way, one boot-loader, one firmware and one or more Field-Programmable Gate Array (FPGA) software modules can be running on a component like a circuit pack. For each software module running on the entity, the name and version information is provided. The management of inactive/standby software modules and of the software upgrade or downgrade life-cycle are outside the scope of the base inventory model and can be addressed in other models which augment the base inventory model such as the model defined in . The software and hardware components share the same attributes of the component and have similar replaceability requirements. Generally, the device also has other software data, for example, one or more records of software patches that have been applied. The software components lifecycle (such as activation, deactivation, installation, storage, removal, etc.) is outside the scope of this document and defined in other documents such as .

Changes Since RFC 8348 This document re-defines some attributes listed in , based on some integration experience for network inventory data.

Part Number According to the description in , the attribute named "model-name" under the component, is preferred to have a customer-visible part number value. "Model-name" is not straightforward to understand, and therefore, in this model the attribute is called "part-number".

Component identifiers There are some use cases where the name of the components are assigned and changed by the operator. In these cases, the assigned names are also not guaranteed to be always unique. In order to support these use cases, this model is not aligned with in defining the component name as the key for the component list. Instead, the name is defined as an optional attribute and the component-id is defined as the key for the component list (in alignment with the approach followed for the network-element list).

Parent relative position There are some use cases where the parent relative position is not reported as an integer but as a string. In order to support these use cases and allowing a straightforward match between the relative position definition in the device and in the network inventory, this model is defining the 'parent-rel-pos' data node as a string instead of as an integer. If the device reports the relative position as an integer, e.g., using the device model defined in , the integer value reported by the device can be mapped into a string within the network inventory.

Network Inventory Tree Diagram shows the tree diagram of the YANG data model defined in module "ietf-network-inventory" ().

Network inventory tree diagram ../../component/component-id +--ro parent-rel-pos? string +--ro is-main? boolean ]]>

YANG Data Model for Network Inventory

Network inventory YANG module WG List: Editor: Chaode Yu Editor: Sergio Belotti Editor: Jean-Francois Bouquier Editor: Fabio Peruzzini Editor: Phil Bedard "; description "This module defines a base model for retrieving network inventory. 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. 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."; revision 2026-09-16 { description "Initial version"; reference "RFC XXXX: A YANG Data Model for Network Inventory."; } /* * Identities */ identity non-hardware-component-class { description "Base identity for non hardware components (e.g., software components) in a managed device."; } identity ne-type { description "Base identity for network element (NE) types."; } identity ne-physical { base nwi:ne-type; description "A physical network element (NE). "; } /* * Types */ typedef ne-ref { type leafref { path "/nwi:network-inventory/nwi:network-elements" + "/nwi:network-element/nwi:ne-id"; require-instance false; } description "This type is intended to be used by data models that need to reference Network Element."; } /* * Groupings */ grouping component-ref { description "This grouping is intended to be used by data models that need to reference a component within a Network Element."; leaf ne-ref { type nwi:ne-ref; description "The reference to the Network Element which contains the component to be referenced."; } 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"; require-instance false; } description "The reference to the component."; } } grouping port-ref { description "This grouping is intended to be used by data models that need to reference a port component within a Network Element."; leaf ne-ref { type nwi:ne-ref; description "The reference to the Network Element which contains the port to be referenced."; } leaf port-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"; require-instance false; } description "The reference to the port component. Note: the class of the referenced port component MUST be 'ianahw:port' or a derived identity."; } } grouping basic-common-entity-attributes { description "The set of basic attributes which are common to all the entities (e.g., component, network elements, location, passive entities) defined in this module and in other inventory modules."; leaf uuid { type yang:uuid; description "The Universally Unique Identifier of the entity (e.g., component)."; } leaf name { type string; description "The name of the entity (e.g., component), as specified by a network operator, that provides a non-volatile 'handle' for the entity. The The network operator can specify a different value anytime during the entity lifetime. If no value is discovered, the server MAY set the value of this node to a locally unique value in the operational state."; } leaf alias { type string; description "The alias name of the entity (e.g., component). This alias name can be specified by a network operator."; } leaf description { type string; description "The textual description of the entity (e.g., component)."; } } grouping ne-component-common-entity-attributes { description "The set of attributes which are common to all the entities (e.g., component, network elements) defined in this module."; uses basic-common-entity-attributes; list software-rev { key "name"; description "The list of the software modules representing the running software images within the entity (e.g., component)."; leaf name { type string; description "The vendor-specific name of the software module."; } leaf revision { type string; description "The vendor-specific revision string of the software module when not implicitly defined as part of the name of the software module."; } list patch { key "revision"; description "The list of the running software patches for the software module."; leaf revision { type string; description "The vendor-specific revision string of the software patch when not implicitly defined as part of the name or revision of the software module."; } } } leaf mfg-name { type string; description "The name of the manufacturer of this entity (e.g., component)."; } leaf product-name { type string; description "The vendor-specific and human-interpretable string describing the entity (e.g., component) type. It is expected that vendors assign unique product names to different entity (e.g., component) types within the scope of the vendor."; } } grouping component-attributes { description "The set of common attributes of a component. This grouping is intended also to be re-used by data models that need to report the common attributes of a component."; leaf component-id { type string; description "An identifier that uniquely identifies the component in a node."; } leaf class { type union { type identityref { base ianahw:hardware-class; } type identityref { base nwi:non-hardware-component-class; } } mandatory true; description "The type of the component."; } uses ne-component-common-entity-attributes { refine "software-rev" { reference "RFC 6933: Entity MIB (Version 4) - entPhysicalSoftwareRev"; } refine "mfg-name" { description "The name of the manufacturer of this component. The preferred value is the manufacturer name string actually printed on the component itself (if present). Note that comparisons between instances of the 'part-number', 'software-rev', and 'serial-number' nodes are only meaningful amongst components with the same value of 'mfg-name'. If the manufacturer name string associated with the component is unknown to the server, then this node is not instantiated."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalMfgName"; } } leaf hardware-rev { type string; description "The vendor-specific hardware revision string for the component. The preferred value is the hardware revision identifier actually printed on the component itself (if present)."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalHardwareRev"; } leaf mfg-date { type yang:date-and-time; description "The date of manufacturing of the component."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalMfgDate"; } leaf part-number { type string; description "The vendor-specific part number of the component type. It is expected that vendors assign unique part numbers to different component types within the scope of the vendor."; } leaf serial-number { type string; description "The vendor-specific serial number of the component instance. It is expected that vendors assign unique serial numbers to different component instances within the scope of the 'part-number'."; } leaf asset-id { type string; description "This node is an asset tracking identifier for the component, as specified by a network operator. A server implementation MAY map this leaf to the entPhysicalAssetID MIB object. Such an implementation needs to use some mechanism to handle the differences in size and characters allowed between this leaf and entPhysicalAssetID. The definition of such a mechanism is outside the scope of this document."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalAssetID"; } leaf is-fru { type boolean; description "This node indicates whether or not this component is considered a 'field-replaceable unit' by the vendor. If this node contains the value 'true', then this component identifies a field-replaceable unit. For all components that are permanently contained within a field-replaceable unit, the value 'false' should be returned for this node."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalIsFRU"; } leaf-list uri { type inet:uri; description "This node contains identification information about the component."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalUris"; } } /* * Data Nodes */ container network-inventory { config false; description "Top-level container for network inventory."; container network-elements { description "The top-level container for the list of network elements within the network."; list network-element { key "ne-id"; description "The list of network elements within the network."; leaf ne-id { type string; description "An identifier that uniquely identifies the NE in a network."; } leaf ne-type { type identityref { base nwi:ne-type; } default "nwi:ne-physical"; description "The network element type."; reference "RFC XXXX: A YANG Data Model for Network Inventory, Section 3."; } uses ne-component-common-entity-attributes; leaf product-rev { type string; description "The vendor-specific product revision string for the network-element."; } container components { description "The top-level container for the list of components within a network element."; list component { key "component-id"; description "The list of components within a network element."; uses component-attributes; leaf-list parent { type leafref { path "../../component/component-id"; require-instance false; } description "The identifiers of all the components that physically contain this component. If this list is empty, this component is not contained in any other component but it is contained in the network-element."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalContainedIn"; } leaf parent-rel-pos { when 'count(../parent) < 2' { description "This data node is applicable only when this component is contained in the network-element or in only one parent component."; } type string; description "The relative position with respect to the parent component among all the sibling components. The format of this string is implementation-specific. When mapping from RFC 6933, the entPhysicalParentRelPos integer value SHOULD be encoded as an integer string."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalParentRelPos"; } leaf is-main { when "derived-from-or-self(../nwi:class, " + "'ianahw:chassis')"; type boolean; description "This node indicates whether the chassis is taking or not the 'main' role. This node is applicable only to scenarios where the network element contains chassis components which can take or not the 'main' role (e.g., multi-chassis network elements). It is therefore omitted in scenarios where the network element does not contain chassis components which can can take or not the 'main' role (e.g., single-chassis network elements)."; } } } } } } } ]]>

Operational Considerations The network inventory YANG data model defined in the document is intended to report the actual inventory data that a network controller knows of the network elements and components actually installed within the network. Therefore, this data model provides a read-only perspective of the network inventory information. It is worth noting that some information reported within this YANG data model can be configured on the device through mechanisms which are outside the scope of this document. As outlined in , per the definition of and , the network inventory model is a network model. This information can be provided by a network controller to a higher level hierarchical network controller, to an Inventory OSS or to any other type of application which needs to discover the network inventory information. For example, in the context of ACTN, the network inventory YANG data model can be used at the MPI interfaces, as defined in , or on an interface, not defined in between the MDSC and the Inventory OSS. The information in the model is discovered by the controller through mechanisms which are outside the scope of this document. Note that distinguishing between the cases where a NE is unreachable versus decommissioned depends on the mechanism used for discovering this information and is outside the scope of this document. For example, the network controller can collect this information by reading it from the devices using the device model supported by the devices. This model does not constrain the device models used on the device: the YANG data model defined in is an option but other options (e.g., vendor specific interfaces or YANG data models) are also allowed. In case some information is not provided by the device, the network controller SHALL omit this information unless this information is known by other sources of information (e.g., through local configuration within the network controller). In case of hierarchical controllers, a hierarchical network controller can also collect the network inventory information from its lower level network controllers using this YANG data model (or other mechanisms which are outside the scope of this document) and report the combined network inventory information to a higher level network controller, to an Inventory OSS or to any other type of application which needs to discover the network inventory information. Since this YANG data model reports what it is actually installed in the network, if a component (e.g., a board) is physically removed from the network, also its descendant components (e.g., daughter boards and ports) are also physically removed from the network and, as a consequence, from the inventory data being reported through this YANG data model. If the inventory system defined by this document is to be deployed into a network which has a preexisting inventory system, it is worth noting that existing deployments are based on proprietary Inventory OSS and that the migration path is highly dependent on the specific proprietary solution. Therefore, the migration processes are operator dependent: it is expected that the deployment of the standard YANG-based solution on the controllers will take some time and its integration with existing Inventory OSSes will also take longer time. In a longer term, the network controllers could provide inventory information, using this YANG data model, also to next generation OSSes. When this model is used, the source of truth for the inventory data in the scope of this model is the network controller providing this data. Some legacy inventory information (e.g., inactive assets, warehouse spares, procurement or commercial metadata) fall outside the scope of the base model.

Security Considerations This section is modeled after the template described in . The "ietf-network-inventory" YANG module defines a data model that is designed to be accessed via YANG-based management protocols, such as Network Configuration Protocol (NETCONF) and RESTCONF . These YANG-based management protocols (1) have to use a secure transport layer (e.g., SSH , TLS , and QUIC ) and (2) have to use mutual authentication. The Network Configuration Access Control Model (NACM) 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. 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. Specifically, the following subtrees and data nodes have particular sensitivities/vulnerabilities:

• "/nwi:network-elements"

• This subtree reports the inventory information for all the network elements and their hardware components deployed within the network as well as of the software modules being discovered as running on these network elements and components. Unauthorized access to this subtree can disclose this information. A malicious attacker can use this information to perform targeted attacks to network elements, hardware components or software modules with known vulnerabilities.

• In large networks, the massive volume of reported data can cause scalability issues, as reported in . A malicious attacker could leverage this to cause resource exhaustion.

Modules that use the groupings that are defined in this document should identify the corresponding security considerations. For example, reusing the 'component-attributes' grouping may expose sensitive information.

IANA Considerations IANA is requested to register the following URI in the "ns" registry within the "IETF XML Registry" group : IANA is requested to register the following YANG module in the "YANG Module Names" registry within the "YANG Parameters" registry group.

References Normative References IANA n.d. IANA n.d. This document defines a YANG data model for the management of hardware on a single server. Datastores are a fundamental concept binding the data models written in the YANG data modeling language to network management protocols such as the Network Configuration Protocol (NETCONF) and RESTCONF. This document defines an architectural framework for datastores based on the experience gained with the initial simpler model, addressing requirements that were not well supported in the initial model. This document updates RFC 7950. In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions for improvements. RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined special meanings. YANG is a data modeling language used to model configuration data, state data, Remote Procedure Calls, and notifications for network management protocols. This document describes the syntax and semantics of version 1.1 of the YANG language. YANG version 1.1 is a maintenance release of the YANG language, addressing ambiguities and defects in the original specification. There are a small number of backward incompatibilities from YANG version 1. This document also specifies the YANG mappings to the Network Configuration Protocol (NETCONF). The Network Configuration Protocol (NETCONF) defined in this document provides mechanisms to install, manipulate, and delete the configuration of network devices. It uses an Extensible Markup Language (XML)-based data encoding for the configuration data as well as the protocol messages. The NETCONF protocol operations are realized as remote procedure calls (RPCs). This document obsoletes RFC 4741. [STANDARDS-TRACK] This document defines a collection of common data types to be used with the YANG data modeling language. It includes several new type definitions and obsoletes RFC 6991. This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used for managing multiple logical and physical entities managed by a single Simple Network Management Protocol (SNMP) agent. This document specifies version 4 of the Entity MIB. This memo obsoletes version 3 of the Entity MIB module published as RFC 4133. The standardization of network configuration interfaces for use with the Network Configuration Protocol (NETCONF) or the RESTCONF protocol requires a structured and secure operating environment that promotes human usability and multi-vendor interoperability. There is a need for standard mechanisms to restrict NETCONF or RESTCONF protocol access for particular users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. This document defines such an access control model. This document obsoletes RFC 6536. YANG is a data modeling language used to model configuration and state data manipulated by the Network Configuration Protocol (NETCONF), NETCONF remote procedure calls, and NETCONF notifications. [STANDARDS-TRACK] Informative References TM Forum OpenConfig Working Group FiberCop Vodafone Huawei Old Dog Consulting Cisco This document explores the applicability of the Abstraction and Control of TE Networks (ACTN) architecture to Packet Optical Integration (POI) within the context of IP/MPLS and optical internetworking. It examines the YANG data models defined by the IETF that enable an ACTN-based deployment architecture and highlights specific scenarios pertinent to Service Providers. Existing IETF protocols and data models are identified for each multi-technology scenario (packet over optical), particularly emphasising the Multi-Domain Service Coordinator to Provisioning Network Controller Interface (MPI) within the ACTN architecture The IETF has produced many modules in the YANG modeling language. The majority of these modules are used to construct data models to model devices or monolithic functions. A small number of YANG modules have been defined to model services (for example, the Layer 3 Virtual Private Network Service Model (L3SM) produced by the L3SM working group and documented in RFC 8049). This document describes service models as used within the IETF and also shows where a service model might fit into a software-defined networking architecture. Note that service models do not make any assumption of how a service is actually engineered and delivered for a customer; details of how network protocols and devices are engineered to deliver a service are captured in other modules that are not exposed through the interface between the customer and the provider. Data models provide a programmatic approach to represent services and networks. Concretely, they can be used to derive configuration information for network and service components, and state information that will be monitored and tracked. Data models can be used during the service and network management life cycle (e.g., service instantiation, service provisioning, service optimization, service monitoring, service diagnosing, and service assurance). Data models are also instrumental in the automation of network management, and they can provide closed-loop control for adaptive and deterministic service creation, delivery, and maintenance. This document describes a framework for service and network management automation that takes advantage of YANG modeling technologies. This framework is drawn from a network operator perspective irrespective of the origin of a data model; thus, it can accommodate YANG modules that are developed outside the IETF. Traffic Engineered (TE) networks have a variety of mechanisms to facilitate the separation of the data plane and control plane. They also have a range of management and provisioning protocols to configure and activate network resources. These mechanisms represent key technologies for enabling flexible and dynamic networking. The term "Traffic Engineered network" refers to a network that uses any connection-oriented technology under the control of a distributed or centralized control plane to support dynamic provisioning of end-to- end connectivity. Abstraction of network resources is a technique that can be applied to a single network domain or across multiple domains to create a single virtualized network that is under the control of a network operator or the customer of the operator that actually owns the network resources. This document provides a framework for Abstraction and Control of TE Networks (ACTN) to support virtual network services and connectivity services. This document captures the current syntax used in YANG module tree diagrams. The purpose of this document is to provide a single location for this definition. This syntax may be updated from time to time based on the evolution of the YANG language. This document defines two strategies for handling long lines in width-bounded text content. One strategy, called the "single backslash" strategy, is based on the historical use of a single backslash ('\') character to indicate where line-folding has occurred, with the continuation occurring with the first character that is not a space character (' ') on the next line. The second strategy, called the "double backslash" strategy, extends the first strategy by adding a second backslash character to identify where the continuation begins and is thereby able to handle cases not supported by the first strategy. Both strategies use a self-describing header enabling automated reconstitution of the original content. Huawei Nokia Vodafone FiberCop Cisco This document defines a YANG data model for Network Inventory location (e.g., site, room, rack, geo-location data), which provides location information with different granularity levels for inventoried network elements. Accurate location information is useful for network planning, deployment, and maintenance. However, such information cannot be obtained or verified from the Network Elements themselves. This document defines a location model for network inventory that extends the base inventory with comprehensive location data. This RFC is a re-release of RFC 1098, with a changed "Status of this Memo" section plus a few minor typographical corrections. This memo defines a simple protocol by which management information for a network element may be inspected or altered by logically remote users. [STANDARDS-TRACK] Huawei China Mobile Huawei Orange This document extends the base Network Inventory YANG model to support non-physical network elements (NEs), such as controllers, virtual routers, and virtual firewalls, as well as software components like platform operating systems and software modules. In addition to the software revisions and patches already defined in the base model, this extension introduces software status and time stamp information. This document provides guidelines for authors and reviewers of specifications containing YANG data models, including IANA-maintained YANG modules. Recommendations and procedures are defined, which are intended to increase interoperability and usability of Network Configuration Protocol (NETCONF) and RESTCONF protocol implementations that utilize YANG modules. This document obsoletes RFC 8407; it also updates RFC 8126 by providing additional guidelines for writing the IANA considerations for RFCs that specify IANA-maintained YANG modules. This document describes an HTTP-based protocol that provides a programmatic interface for accessing data defined in YANG, using the datastore concepts defined in the Network Configuration Protocol (NETCONF). The Secure Shell Protocol (SSH) is a protocol for secure remote login and other secure network services over an insecure network. This document describes the SSH authentication protocol framework and public key, password, and host-based client authentication methods. Additional authentication methods are described in separate documents. The SSH authentication protocol runs on top of the SSH transport layer protocol and provides a single authenticated tunnel for the SSH connection protocol. [STANDARDS-TRACK] This document specifies version 1.3 of the Transport Layer Security (TLS) protocol. TLS allows client/server applications to communicate over the Internet in a way that is designed to prevent eavesdropping, tampering, and message forgery. This document obsoletes RFC 8446, which specified TLS 1.3. This document obsoletes RFC 5246 (specifying TLS 1.2) and RFCs 5077, 6961, 7627, and 8422, all of which pertain to TLS 1.2 or earlier, and updates RFCs 5705 and 6066. This document also specifies new requirements for TLS 1.2 implementations. This document defines the core of the QUIC transport protocol. QUIC provides applications with flow-controlled streams for structured communication, low-latency connection establishment, and network path migration. QUIC includes security measures that ensure confidentiality, integrity, and availability in a range of deployment circumstances. Accompanying documents describe the integration of TLS for key negotiation, loss detection, and an exemplary congestion control algorithm. This document describes an IANA maintained registry for IETF standards which use Extensible Markup Language (XML) related items such as Namespaces, Document Type Declarations (DTDs), Schemas, and Resource Description Framework (RDF) Schemas. This document describes a Uniform Resource Name (URN) namespace (RFC 3406) for the assignment of the Common Language Equipment Identifier (CLEI) code, which is used in messages standardized by ANSI. The URN namespace is managed by Telcordia Technologies, Inc., as the maintenance agent for ANSI T1.213. The CLEI code is a globally unique, ten-character alphanumeric intelligent code assigned by Telcordia Technologies at the request of equipment suppliers. The CLEI code identifies communications equipment by specifying product type and features. There is a one-to-one relationship between a CLEI code and supplier's product ID (the manufacturer's name and the part number along with its version number). This memo provides information for the Internet community. This document defines encoding rules for representing configuration data, state data, parameters of Remote Procedure Call (RPC) operations or actions, and notifications defined using YANG as JavaScript Object Notation (JSON) text. Futurewei Nokia Ciena FiberCop NBN This document presents a YANG data model for tracking and managing passive network inventory. The model augments the base network inventory model.

Comparison With OpenConfig Platform YANG Data Model Because an increasing number of devices implement OpenConfig, this appendix compares the OpenConfig Platform model, defined in , with the base network inventory model, defined in this document, to ensure network controllers can accurately report discovered data. The OpenConfig platform data model, defined by the "openconfig-platform" and "openconfig-platform-types" modules in , is a device model that uses a generic component concept to describe internal components and containers, similar to the models in and in this document. Therefore, compares the component attributes between the "openconfig-platform" YANG module in and the "ietf-network-inventory" module in . Comparison between openconfig platform and inventory data models

Attributes in "openconfig-platform"	Attributes in "ietf-network-inventory"	Remark
name	name
type	class	See for the comparison between "oc-platform-type:OPENCONFIG_HARDWARE_COMPONENT" and "ianahw:hardware-class"
id	uuid
location	location
description	description
mfg-name	mfg-name
mfg-date	mfg-date
hardware-version	hardware-rev
firmware-version	software-rev*	Items of "software-rev" list that provide firmware information
software-version	software-rev*	Items of "software-rev" list that provide software information
serial-no	serial-number
part-no	part-number
clei-code	uri	CLEI code can be mapped into a URI as defined in
removable	is-fru
oper-status		State data
empty		If there is no other component that refers to a holder as a parent, it can be considered empty
parent	parent-references
redundant-role		Functional information, may be part of a future augmentation
last-switchover-reason		State data
last-switchover-time		State data
last-reboot-reason		State data
last-reboot-time		State data
switchover-ready		State data
temperature		Performance data
memory		Performance data
allocated-power		State/performance data
used-power		State/performance data
pcie		Alarm data
properties		Generic properties can be handled as part of "description"
subcomponents

As mentioned in , state data, performance data, and alarm data are out of scope of the data model defined in this document, and they should be defined in other data models separately. For the same reason some component specific structures in "openconfig-platform", like the one defined for fan, backplane, controller-card, etc., are considered out of scope since they provide specialized operational and alarm data for those components. compares the identities derived from "oc-platform-type:OPENCONFIG_HARDWARE_COMPONENT" with those derived from "ianahw:hardware-class". This comparison highlights that the base network inventory model aligns with the OpenConfig Platform model also regarding hardware component "type"/"class" definition. Comparison between openconfig-platform OPENCONFIG_HARDWARE_COMPONENT and IANA hardware-class derived identities

"oc-platform-type:OPENCONFIG_HARDWARE_COMPONENT"	"ianahw:hardware-class"
CHASSIS	chassis
BACKPLANE	backplane
FABRIC	module
POWER_SUPPLY	power-supply
FAN	fan
FAN_TRAY	module
FAN_TRAY_CONTROLLER	module
SENSOR	sensor
LINECARD	module
CONTROLLER_CARD	module
PORT	port
USB_PORT	port
TRANSCEIVER	module
CPU	cpu
STORAGE	storage-drive
INTEGRATED_CIRCUIT	module
WIFI_ACCESS_POINT	N/A (technology specific)
FPGA	module

Overall, the analysis in this appendix confirms that the base network inventory YANG data model can be populated with data discovered from devices running OpenConfig.

Terminology of Container Within this document , term "container" represents an hardware component class capable of containing one or more removable physical entities, e.g., a slot in a chassis which is capabable to contain a board. terminology mapping

terminology of IVY base model	terminology in other models
container	holder

Efficiency Issue During the integration with OSS in some operators, some efficiency/scalability concerns have been discovered when synchronizing network inventory data for big networks. As outlined in , these efficiency and scalability issues can pose security issues. While implementing NACM and protocol-specific filtering mechanisms (e.g., RESTCONF filtering ) mitigates these efficiency and scalability concerns, full resolution may require further protocol enhancements beyond the scope of this document. Considering that relational databases are widely used by existing OSS systems and also by some network controllers, the inventory objects are most likely to be saved in different tables. With the model defined in this document, when doing a full synchronization, network controller needs to convert all inventory objects of each NE into component objects and combine them together into a single list, and then construct a response and send to OSS or MDSC. The OSS or MDSC needs to classify the component list and divide them into different groups, in order to save them in different tables. The combining-regrouping steps are impacting the network controller & OSS/MDSC processing, which may result in efficiency/scalability limitations in large scale networks. An alternative YANG model structure, which defines the inventory objects directly, instead of defining generic components, has also been analyzed. However, also with this model, there still could be some scalability limitations when synchronizing full inventory resources in large scale networks. This scalability limitation is caused by the limited transmission capabilities of HTTP protocol. This scalability limitation should be solved at protocol level rather than data model level. The model proposed by this document is designed to be as generic as possible so as to cover future special types of inventory objects that could be used in other technologies, that have not been identified yet. If the inventory objects were to be defined directly with fixed hierarchical relationships in the YANG model, this new type of inventory objects needs to be manually defined, which is not a backward compatible change and therefore is not an acceptable approach for implementation. With a generic model, it is only necessary to augment a new component class and extend some specific attributes for this new inventory component class, which is more flexible. The main scope of this documento is to define the generic data model, enabling a flexible and backward compatible approach for other technologies. Solution description to efficiency/scalability limitations mentioned above is considered as out-of-scope.

Examples of ports This appendix provides some examples of port implementations and how they can be modelled using the "ietf-network-inventory" module defined in . shows an example of a single board which contains three types of port:

1. An integrated port (non-pluggable);
2. An empty port;
3. A pluggable port

Example of a board with different types of ports

JSON Examples This appendix contains an example of an instance data tree in JSON encoding , instantiating the "ietf-network-inventory" module to describe the three types of ports on a single board, as shown in .

Example of multi-chassis network elements This appendix provides some examples of multi-chassis network elements and how they can be modelled using the "ietf-network-inventory" module defined in . Multi-chassis network elements are network elements comprised of two or more chassis interconnected, in principle, with any topology. Stacked switches are an example of multi-chassis which consist of multiple standalone switches that are interconnected through dedicated stack ports and cables and managed as a single logical unit. Stacked switches:

• are connected using a daisy-chain or a ring topology
• are managed using a single IP Address
• require synchronized software-upgrade
• use Priority/MAC-Addr(s) to decide Main/Members selection and communication.

and describe two examples of stacked switches with three switches (pizza boxes) connected in a daisy-chain or ring topology.

Example of stacked switches in a daisy chain topology

Example of stacked switches in a ring topology

Using the base network inventory YANG data model, each stackable switch can be modelled as a chassis within the same network element, which models the stacked switches. The stack ports are modelled like other ports. The stack cables are not reported using the base network inventory YANG data model but can be reported using the passive network inventory YANG data model under definition in . Cascaded switches are another example of multi-chassis which consist of multiple standalone switches that are interconnected and managed as a single logical unit. Cascaded switches:

• are usually connected in a tree topology
• are managed using a single IP Address
• the root of the tree is configured as Main.

describe an example of cascaded switches with three chassis connected in a tree topology.

Example of cascaded switches in a tree topology | 4 || | | | ... | | |+---+| | | | | | | | | | | | | | | | | |+---+| | | | ... | | ... || 6 |<-----+ | | ... | | | |+---+| | | | | | | | | | | | | | | | ... | | | | | | | | | | | |+---+| | | |+---+| | | ||10 || | | ||10 || | | |+---+| | | |+---+| | | +----------------------------------------------+ | | | | | | +-------------------------------+ | | | S1 | Chassis 2 | S16 | | | | | | | | | | | | | | | |+---+| | | | +---> 5 || | | | |+---+| | | | | | | | | | | | | | +-------------------------------+ | | | +-------------------------------+ | | S1 | Chassis 3 | S16 | | | | | | | | | | | | | | | | | | | |+---+| | | | || 7 |<--+ | | |+---+| | | | | +-------------------------------+ ]]>

Using the base network inventory YANG data model, each interconnected switch is modelled as a chassis component of the same network element. The ports used to interconnect these switches are normal (traffic) ports and modelled like other ports. The interconnecting cables are not reported using the base network inventory YANG data model but can be reported using the passive network inventory model under definition in .

JSON Examples This appendix contains an example of an instance data tree in JSON encoding , instantiating the "ietf-network-inventory" model to describe the three examples of multi-chassis NEs, as shown in , and .

• Note: the base inventory model allows reporting only the chassis and ports configuration. Reporting the link between the chassis of the same NE is outside the scope of the base inventory model. The YANG data model under definition in as an augmentation of the base inventory YANG data model can be used to provide this additional information.

Example of non-modular network elements This appendix provides some examples of non-modular network elements and how they can be modelled using the "ietf-network-inventory" module defined in . Non-modular network elements (also known as "pizza boxes") are network elements comprised of a single chassis as a self-contained system. A non-modular network element does not have any slots to take cards so it cannot take any non-field replaceable modules other than pluggable ports. describes an example of a pizza box with 8 ports.

Example of an 8 ports pizza box device

Using the base network inventory YANG data model a non-modular network element can be modelled as a network element containing only one chassis and ports (as child components of the chassis). Reporting the single chassis component within a non-modular network element is required because the chassis component is the type of component which provides the physical characteristics of the network element chassis (the network element is defined just as an assembly of components) and its location, using the network inventory YANG data model under definition in .

JSON Examples This appendix contains an example of an instance data tree in JSON encoding , instantiating the "ietf-network-inventory" module to describe the pizza box example, as shown in .

Acknowledgments The authors of this document would like to thank the authors of for having identified the gap and requirements to trigger this work. The authors of this document would like to thank Adrian Farrel, Alexander Clemm, Brad Peters, Camilo Cardona, Daniele Ceccarelli, Gabriele Galimberti, Jan Lindblad, Joe Clarke, Mahesh Jethanandani, Mohamed Boucadair, Prasenjit Manna, Rob Wilton, Qin Wu, Qiufang Ma, and Swamynathan Balasundaram for their valuable input to the technical discussions during the development of this document. The authors would like to thank Reshad Rahman for his YANG Doctor eview. The authors would like to thank Valery Smyslov, Samier Barguil, and for their Security Directorate, Operational Directorate (ops-dir), and General Area Review Team (Gen-ART) reviews. This document was prepared using kramdown.

Contributors Huawei Technologies

italo.busi@huawei.com

Futurewei Technologies

aihuaguo.ietf@gmail.com

Nokia

victor.lopez@nokia.com

Huawei Technologies

lana.wubo@huawei.com

China Unicom

zhangcf80@chinaunicom.cn

Telefonica

oscar.gonzalezdedios@telefonica.com

Ciena

ndavis@ciena.com

Cisco

rmanzott@cisco.com