]> Huawei

lana.wubo@huawei.com

Orange

mohamed.boucadair@orange.com

China Mobile

zhouchengyjy@chinamobile.com

Huawei

bill.wu@huawei.com

Operations and Management Network Inventory YANG Automation Network Digital Map Network Inventory Network Operation Network Topology This document defines a YANG data model to map the network inventory data with the topology data to form a base underlay network. The data model facilitates the correlation between the layer (e.g., Layer 2 or Layer 3) topology information and the inventory data of the underlay network for better service provisioning, network maintenance operations, and other assessment scenarios. Discussion Venues Discussion of this document takes place on the Network Inventory YANG Working Group mailing list (inventory-yang@ietf.org), which is archived at . Source for this draft and an issue tracker can be found at .

Introduction defines the base network inventory model to aggregate the inventory data of Network Elements (NEs). This data includes identification of these NEs and their hardware, firmware, and software components. Examples of inventory hardware components could be rack, shelf, slot, board, or physical port. Examples of inventory software components could be platform Operating System (OS), software-modules, bios, or boot-loader . In order to ease navigation from (or to) inventory and network topologies, this document extends the network topology data model for network inventory mapping: "ietf-network-inventory-topology" (). This data model provides a mechanism for the correlation with existing network and topology data models, such as "A YANG Network Data Model for Service Attachment Points (SAPs)" , "A YANG Data Model for Layer 2 Network Topologies" , and "A YANG Data Model for Layer 3 Topologies" . Similar to the base inventory data model , the network inventory topology does not make any assumption about involved NEs and their roles in topologies. As such, the mapping model can be applied independent of the network type (optical local loops, access network, core network, etc.) and application.

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:

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Conventions and Definitions The meanings of the symbols in the YANG tree diagrams are defined in . This document uses terms defined in .

Sample Use Cases of the Data Model

Determine Available Resources of Service Attachment Points (SAPs) The inventory topology data model can be used as a basis for correlating underlay information, such as physical port components. exemplifies this usage. During service provisioning, to check available physical port resources, the SAPs information can be associated with the underlay inventory information and interface information associated with the inventory topology, e.g., "parent-termination-point" of SAP Model can be associated with the "port-component-ref" of the inventory topology data model, which can be used to check the availability and capacity of physical ports.

An Example Usage of Network Inventory Topology

"What-if" Scenarios defines Network Digital Twin (NDT) as a virtual representation of the physical network. Such representation is meant to be used to analyze, diagnose, emulate, and then manage the physical network based on data, models, and interfaces. defines Service and Infrastructure Maps (SIMAP) as an abstraction model that provides a unified view of both service and infrastructure information, enabling correlation between service requirements and underlying resource capabilities. Both architectures require accurate mapping between logical network topology and physical inventory as a foundational data layer. This model provides the essential physical resource information to such systems, enabling them to perform accurate "what-if" analysis (e.g., impact prediction of hardware EOL, path re-optimization under resource constraints, service availability assessment).

Module Tree Structure An overview of the structure of the "ietf-network-inventory-topology" module is shown in .

The Structure of the Network Inventory Mapping Data Model

The module defines two features "inventory-to-topology-navigate" and "topology-to-inventory-navigate" to control the navigation direction (from topology to inventory and vice versa). The module augments the "ietf-network-topology" module as follows:

• Inventory mapping attributes for nodes, links, and termination points: The corresponding containers augments the topology module with the references to the base network inventory The inventory topology model associates inventory data with overlay topologies. It can be used as the "supporting-networks" of SAP, Layer 2, or Layer 3 topologies.

Link Extensions This document adds a lightweight "link-type" leaf to the topology link mapping to enable basic physical media classification.

• "link-type" – A string indicating the link media type, such as "copper", "fiber", or "coax". For wireless media, values such as "microwave", or "wifi" may be used

The "link-type" serves as a lightweight discriminator that guides to the appropriate specialized inventory model for detailed resource information. For example, wired media (fiber, copper) typically reference a passive network inventory model, such as the one defined in .

Port-Breakout Capability High-density Ethernet ports (e.g., 400 Gb/s DR4) can be split into multiple independent lower-speed channels. The breakout channels represent the intrinsic capability of the port to be partitioned, regardless of whether the port is currently configured as a trunk or as a breakout port. A trunk port is associated with exactly one physical interface. A breakout port is a port that is decomposed into two or more physical interfaces; those interfaces may run at the same or different speeds and may consume the same or a different number of breakout channels. The container "port-breakout" is added under the termination-point augmentation. It lists the logical channels into which the single physical port can be divided. Only termination-points whose parent port is breakout-capable need to instantiate the container; otherwise the container is omitted, keeping the topology model minimal for the common non-breakout case. Breakout channel is an atomic resource element obtained by partitioning a breakout port. One physical interface may be associated with one or more breakout channels, but one breakout channel MUST NOT be associated with more than one physical interface. Appendix B provides example configurations. It is assumed that a port which supports breakout can be configured either as a trunk port or as a breakout port. Interface channelisation (e.g., VLAN sub-interfaces) is outside the scope of this document and is addressed by the Layer 2 network topology model .

Network Inventory Topology YANG Module This module augments the Network Topology . This module imports the base network inventory . WG List: IVY Editor: Bo Wu Editor: Mohamed Boucadair Author: Cheng Zhou Author: Qin Wu "; description "This YANG module defines a YANG module for network topology and inventory mapping. 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). All revisions of IETF and IANA published modules can be found at the YANG Parameters registry group (https://www.iana.org/assignments/yang-parameters). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; revision 2026-02-28 { description "Initial revision."; reference "RFC XXXX: A Network Data Model for Inventory Topology Mapping"; } // Groupings // Node Grouping with 1:1 mapping to NE grouping node-inventory-mapping-attributes { description "Attributes for mapping a topology node to a Network Element (NE) in the physical inventory."; container inventory-mapping-attributes { description "Container for inventory mapping attributes of a node."; leaf ne-ref { type nwi:ne-ref; description "Reference to the NE in the inventory that corresponds to this topology node. This reference establishes a 1:1 mapping between the logical node and its physical NE."; } } } // TP Grouping with 1:1 mapping to physical port grouping tp-inventory-mapping-attributes { description "Attributes for mapping a topology termination point (TP) to a physical port in the network inventory."; container inventory-mapping-attributes { description "Container for inventory mapping attributes of a TP."; uses nwi:port-ref { refine "port-ref" { description "Reference to the physical port component in the network inventory. This reference establishes a 1:1 mapping between the logical TP and its physical port component."; } } // breakout channels (lightweight, per physical port) container port-breakout { presence "Indicates the port supports channel breakout."; config false; description "Breakout capability of the physical port represented by this TP. One TP maps to one physical port; channels are listed here. This container is present only when the underlying hardware supports partitioning the port into multiple independent channels (e.g., 400G to 4x100G)."; list breakout-channel { key "channel-id"; description "List of breakout channels available on this port. Each entry represents an independent lane or sub-port that can be used for channelized interfaces."; leaf channel-id { type uint16; description "Unique identifier for the breakout channel within the scope of the parent port."; } } // breakout-channel } // port-breakout } } // Link Grouping with placeholder for future augumentation grouping link-inventory-mapping-attributes { description "Attributes for classifying link media type. Detailed inventory reference is intentionally omitted from this model; implementations should use the appropriate specialized inventory modules based on the indicated link-type."; container inventory-mapping-attributes { description "Container for inventory-related attributes of a link. This container provides lightweight media classification. The link-type indicates which specialized inventory model contains detailed resource information: - Wired media (fiber, copper): passive network inventory - Wireless media (microwave, Wi-Fi): wireless-specific inventory Detailed inventory references may be added in future modules."; leaf link-type { type string; description "Classification of the link media type at the topology layer. Example values include 'copper', 'fiber', 'microwave', or 'wifi'."; } } } // Main blocks augment "/nw:networks/nw:network/nw:node" { description "Augments the network topology node with inventory mapping attributes. This enables correlation between the logical node and its physical network element."; uses node-inventory-mapping-attributes; } augment "/nw:networks/nw:network/nt:link" { description "Augments the network topology link with inventory-related attributes."; uses link-inventory-mapping-attributes; } augment "/nw:networks/nw:network/nw:node/nt:termination-point" { description "Augments the TP with inventory mapping attributes for physical port correlation and breakout capability reporting."; uses tp-inventory-mapping-attributes; } } ]]>

Operational Considerations This model enables a network controller to report discovered network topology and inventory information. Automatic discovery serves as the primary mechanism, with selective configuration capabilities provided for scenarios where discovery is not feasible. For typical operations such as service provisioning and network planning, the model offers read-only query access to authoritative mappings between logical topology and physical inventory. The inventory-mapping-attributes containers are defined as read-write (config true) to accommodate cases where automatic discovery is not possible, including:

• Customer-premises equipment (CPE) outside the operator's management domain
• Leased lines and third-party transport resources
• Planned or hypothetical resources for future deployment

In these cases, the operator manually configures the mapping to maintain accurate topology-to-inventory correlation. The following nodes are read-only (config false) as they represent hardware-determined state: port-breakout: Hardware capability determined by physical port characteristics

Security Considerations This section is modeled after the template described in . The "ietf-network-inventory-topology" YANG module defines a data model that is designed to be accessed via YANG-based management protocols, such as NETCONF and RESTCONF . These YANG-based management (1) have to use a secure transport layer (e.g., SSH , TLS , and QUIC {{?RFC9000]) 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. 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). All writable data nodes are likely to be sensitive or vulnerable in some network environments. Write operations (e.g., edit-config) and delete operations to these data nodes without proper protection or authentication can have a negative effect on network operations. The following subtrees and data nodes have particular sensitivities/vulnerabilities: 'ne-ref', 'port-ref', 'link-type': These nodes are sensitive as they establish the mapping between logical topology and physical inventory. Unauthorized modification could lead to incorrect resource allocation or service disruption. 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: 'ne-ref': The references may be used to track the set of network elements. While read-only, they may reveal network infrastructure details. 'port-breakout': This node exposes hardware capabilities.

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

References Normative References Huawei Technologies Nokia Vodafone FiberCop Cisco 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. This document defines an abstract (generic, or base) YANG data model for network/service topologies and inventories. The data model serves as a base model that is augmented with technology-specific details in other, more specific topology and inventory data models. This document defines a YANG data model for representing an abstract view of the provider network topology that contains the points from which its services can be attached (e.g., basic connectivity, VPN, network slices). Also, the model can be used to retrieve the points where the services are actually being delivered to customers (including peer networks). This document augments the 'ietf-network' data model defined in RFC 8345 by adding the concept of Service Attachment Points (SAPs). The SAPs are the network reference points to which network services, such as Layer 3 Virtual Private Network (L3VPN) or Layer 2 Virtual Private Network (L2VPN), can be attached. One or multiple services can be bound to the same SAP. Both User-to-Network Interface (UNI) and Network-to-Network Interface (NNI) are supported in the SAP data model. 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. 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. 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 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 defines a YANG data model for Layer 2 network topologies. In particular, this data model augments the generic network and network topology data models with topology attributes that are specific to Layer 2. This document defines a YANG data model for Layer 3 network topologies. 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. China Mobile China Mobile China Mobile Huawei Orange Orange Digital Twin technology has seen rapid adoption in Industry 4.0. The application of Digital Twin technology in the networking field is meant to develop various rich network applications, realize efficient and cost-effective data-driven network management, and accelerate network innovation. This document presents an overview of the concepts of Network Digital Twin, provides the basic definitions and a reference architecture, lists a set of application scenarios, and discusses such technology's benefits and key challenges. Huawei Everything OPS Telefonica Swisscom This document defines the concept of Service & Infrastructure Maps (SIMAP) and identifies a set of SIMAP requirements and use cases. The SIMAP was previously known as Digital Map. The document intends to be used as a reference for the assessment of the various topology modules to meet SIMAP requirements. Huawei Futurewei Huawei Highstreet Nokia Nokia Nokia Nokia Ciena FiberCop NBN ETRI China Mobile China Mobile Radisys 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]. YumaWorks Orange Huawei This document provides guidelines for authors and reviewers of specifications containing YANG data models, including IANA-maintained 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. Also, this document updates RFC 8126 by providing additional guidelines for writing the IANA considerations for RFCs that specify IANA-maintained modules. 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 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 updates RFCs 5705 and 6066, and obsoletes RFCs 5077, 5246, and 6961. This document also specifies new requirements for TLS 1.2 implementations. 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.

"link-type" Usage Examples This appendix provides examples illustrating the usage of the link-type data node. Scenario: Device SW-1 and device SW-2 are directly connected by a fiber. Physical topology: Key parts of the JSON example is as follows:

JSON Example of an MPO Breakout-Channel Port This appendix provides an example of a 400 Gb/s DR4 port that is physically implemented as four independent 100 Gb/s lanes (an MPO breakout). The lanes are exposed as breakout-channel entries so that the port can later be configured as either a single 400G trunk or four 100G breakout interfaces. The instance data below shows the minimal JSON encoding of the "port-breakout" container for this port.

Acknowledgments The authors wish to thank Italo Busi, Olga Havel, Aihua Guo, Oscar Gonzalez de Dios, and many others for their helpful comments and suggestions.

Contributors Huawei

yuchaode@huawei.com