]> Huawei Technologies

yuchaode@huawei.com

Huawei Technologies

italo.busi@huawei.com

Futurewei Technologies

aihuaguo.ietf@gmail.com

Nokia

sergio.belotti@nokia.com

Vodafone

jeff.bouquier@vodafone.com

TIM

fabio.peruzzini@telecomitalia.it

Telefonica

oscar.gonzalezdedios@telefonica.com

Nokia

victor.lopez@nokia.com

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

Introduction Network hardware inventory management is a key component in operators' OSS architectures. Network inventory is a fundamental functionality in network management and was specified many years ago. Given the emerging of data models and their deployment in operator's management and control systems, the traditional function of inventory management is also requested to be defined as a data model. Network inventory management and monitoring is a critical part of ensuring the network stays healthy, well-planned, and functioning in the operator's network. Network inventory management allows the operator to keep track of what physical network devices are staying in the network including relevant software and hardware. The network inventory management also helps the operator to know when to acquire new assets and what is needed, or to decommission old or faulty ones, which can help to improve network performance and capacity planning. In a gap was identified regarding the lack of a YANG data model that could be used at ACTN MPI interface level to report whole/partial hardware inventory information available at PNC level towards north-bound systems (e.g., MDSC or OSS layer). initial goal was to make possible the augmentation of the YANG data model with network inventory data model but this was never developed and the scope was kept limited to network topology data only. It is key for operators to drive the industry towards the use of a standard YANG data model for network inventory data instead of using vendors proprietary APIs (e.g., REST API). In the ACTN architecture, this would bring also clear benefits at MDSC level for packet over optical integration scenarios since this would enable the correlation of the inventory information with the links information reported in the network topology model. The intention is to define a generic YANG data model that would be as much as possible technology agnostic (valid for IP, optical and microwave networks) and that could be augmented, when required, to include some technology-specific inventory details. defines a YANG data model for the management of the hardware on a single server and therefore it is more applicable to the PNC South Bound Interface (SBI) towards the network elements rather than at the PNC MPI. However, the YANG data model defined in has been used as a reference for defining the YANG network hardware inventory data model. For optical network hardware inventory, the network inventory YANG data model should support the use cases (4a and 4b) and requirements defined in , in order to guarantee a seamless integration at MDSC/OSS/orchestration layers. The proposed YANG data model has been analyzed to cover the requirements and use cases for Optical Network Hardware Inventory. Being based on , this data model should be a good starting point toward a generic data model and applicable to any technology. However, further analysis of requirements and use cases is needed to extend the applicability of this YANG data model to other types of networks (IP and microwave) and to identify which aspects are generic and which aspects are technology-specific for optical networks. This document defines one YANG module: ietf-network-inventory.yang (). Note: review in future versions of this document the related modules, depending on the augmentation relationship. The YANG data model defined in this document conforms to the Network Management Datastore Architecture .

Terminology and Notations The following terms are defined in and are not redefined here: client server augment data model data node The following terms are defined in and are not redefined here: configuration data state data The terminology for describing YANG data models is found in . TBD: Recap the concept of chassis/slot/component/board/... in . Following terms are used for the representation of the hierarchies in the network hardware inventory. Network Element:

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

Rack:

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

Chassis:

• a holder of the device installation.

Slot:

• a holder of the board.

Component:

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

Board/Card:

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

Port:

• an interface on board

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

Tree Diagram A simplified graphical representation of the data model is used in of this document. The meaning of the symbols in these diagrams is defined in .

Prefix in Data Node Names In this document, names of data nodes and other data model objects are prefixed using the standard prefix associated with the corresponding YANG imported modules, as shown in the following table. Prefix Yang Module Reference ianahw iana-hardware ni ietf-network-inventory RFC XXXX yang ietf-yang-types RFC Editor Note: Please replace XXXX with the RFC number assigned to this document. Please remove this note.

YANG Data Model for Network Hardware Inventory

YANG Model Overview Based on TMF classification in , inventory objects can be divided into two groups, holder group and equipment group. The holder group contains rack, chassis, slot, sub-slot while the equipment group contains network-element, board and port. With the requirement of GIS and on-demand domain controller selection raised, the equipment room becomes a new inventory object to be managed besides TMF classification. Logically, the relationship between these inventory objects can be described by below:

In , rack, chassis, slot, sub-slot, board and port are defined as components of network elements with generic attributes. Considering there are some special scenarios, the relationship between the rack and network elements is not 1 to 1 nor 1 to n. The network element cannot be the direct parent node of the rack. So there should be n to m relationship between racks and network elements. And the chassis in the rack should have some reference information to the component. 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 network hardware inventory information that a controller discovers from multiple Network Elements 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 network hardware inventory model when the controller uses the YANG data model defined in to retrieve the hardware from the network elements under its control. Note: review in future versions of this document which attributes from are required also for network hardware inventory and whether there are attributes not defined in which are required for network hardware inventory Note: review in future versions of this document whether to re-use definitions from or use schema-mount.

Common Design for All Inventory Objects For all the inventory objects, there are some common attributes existing. Such as: Identifier: here we suggest to use uuid format which is widely used by development of systems. It could be globally unique easily. Name: name is a human-readable label information which could be used to present on GUI. This name is suggested to be provided by server. Alias: alias is also a human-readable label information which could be modified by user. It could also be present on GUI instead of name. Description: description is a human-readable information which could be also input by user. Description provides more detailed information to prompt users when maintaining. Location: location is a common management requirement of operators. This location could be absolute position, e.g. address, or relative position, e.g. port index. Different types of inventory objects require different types of position.

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

But we refined some attributes in , based on some integration experience we had.

Refinement of RFC8348

New Parent Identifiers' Reference provided an "parent-ref" attribute, which was an identifier reference to its parent component. When the MDSC or OSS systems want to find this component's grandparent or higher hierarchal level component, they need to retrieve this parent-ref step by step. To reduce this duplicated work, we tend to provide a list of hierarchical parent components' identifier reference.

The hierarchical components' identifier could be found by the "component-reference" list. The "index" in this list which starts from 0 is sort by the hierarchical relationship from topmost component to bottom component.

Component-Specific Info Design According to the management requirements from operators, some important attributes are not defined in . These attributes could be component specific and are not suitable to define under the component list node. So we define a choice-case structure for this component-specific extension, which is:

Note: The *-specific-info container is still under discussing, will be enriched in future.

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 quite recognized and we suggest to refine it to part number directly.

Equipment Room Note: add some more attributes about equipment room in the future.

Rack Besides the common attribute mentioned in above section, rack could have some specific attributes, such as attributes about appearance-related attributes and electricity-related attributes. The height, depth and width are described by the figure below (please imaged that the door of rack face to the user):

The attributes for rack includes:

Max-voltage: the maximum voltage could be supported by the rack.

Network Element We consider that some attributes defined in for components are also applicable for network element. Includes:

Note: the attributes of network element are still under discussing.

Efficiency Issue During doing the design of integration with OSS, some efficiency issues have been discovered. More discussion is needed to be done in the future to address this issue. Considering relational database is widely used by traditional OSS systems and part of PNCs, the inventory objects are probably saved in different tables. If the generic model is adopted, when doing a full synchronization, PNC 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 PNC & OSS/MDSC processing, which may result in efficiency issue in large scale networks. We also designed a YANG model which defines the inventory objects directly instead of defining with generic components. There still could be some scalability issues when synchronizing full inventory resource in large scale of networks. This scalability issue is caused by the small transmission capability of HTTP protocol. We think that this scalability should be solved on protocol level instead of some specific data model. In case there are some other special types of inventory objects could be used in other technologies and have not been recognized by us, we would like to provide a generic model. If we define the inventory objects directly and give them fix hierarchical relationships in YANG model, once there is a new type of inventory object needs to be introduced into the model, we need to break down our YANG model and insert the new one, this is incompatible change which is unacceptable by the developer to implement. In comparison, we only need to augment a new component class and extend some specific attributes for this new inventory if we adopt generic model, which is more acceptable. We think this compatible issue is prior to the efficiency issue mentioned above, therefore, we continue to work on generic component model.

Some Other Considerations Note: review in future versions of this document whether the component list should be under the network-inventory instead of under the network-element container Note that in , topology and inventory are two subsets of network information. However, considering the complexity of the existing topology models and to have a better extension capability, we define a separate root for the inventory model. We will consider some other ways to do some associations between the topology model and inventory model in the future. Note: review in future versions of this document whether network hardware inventory should be defined as an augmentation of the network model defined in instead of under a new network-inventory root. The proposed YANG data model has been analyzed to cover the requirements and use cases for Optical Network Inventory. Further analysis of requirements and use cases is needed to extend the applicability of this YANG data model to other types of networks (IP and microwave) and to identify which aspects are generic and which aspects are technology-specific for optical networks.

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

../uuid +--ro parent-rel-pos? int32 +--ro parent-references | +--ro equipment-room-uuid? leafref | +--ro ne-uuid? leafref | +--ro rack-uuid? leafref | +--ro component-references | +--ro component-reference* [index] | +--ro index uint8 | +--ro class? -> ../../../../class | +--ro uuid? -> ../../../../uuid +--ro hardware-rev? string +--ro firmware-rev? string +--ro software-rev? string +--ro serial-num? string +--ro mfg-name? string +--ro part-number? string +--ro asset-id? string +--ro is-fru? boolean +--ro mfg-date? | yang:date-and-time +--ro uri* inet:uri +--ro (component-class)? +--:(chassis) | +--ro chassis-specific-info +--:(container) | +--ro slot-specific-info +--:(module) | +--ro board-specific-info +--:(port) +--ro port-specific-info ]]>

YANG Model for Network Hardware Inventory

WG List: Editor: Chaode Yu Editor: Italo Busi Editor: Aihua Guo Editor: Sergio Belotti Editor: Jean-Francois Bouquier Editor: Fabio Peruzzini "; description "This module defines a model for retrieving network inventory. The model fully conforms to the Network Management Datastore Architecture (NMDA). Copyright (c) 2022 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 2022-07-11 { description "version 3.0.0"; reference "draft-yg3bp-ccamp-inventory-yang-01: A YANG Data Model for Network Inventory."; } revision 2022-03-04 { description "version 3.0.0"; reference "draft-yg3bp-ccamp-inventory-yang-00: A YANG Data Model for Network Inventory."; } revision 2021-11-09 { description "version 2.0.0"; reference "draft-yg3bp-ccamp-optical-inventory-yang-00: A YANG Data Model for Optical Network Inventory."; } revision 2021-10-25 { description "Initial revision."; reference "draft-yg3bp-ccamp-optical-inventory-yang-00: A YANG Data Model for Optical Network Inventory."; } container network-inventory { config false; description "The top-level container for the network inventory information."; uses equipment-rooms-grouping; uses network-elements-grouping; } grouping common-entity-attributes { description "A set of attributes which are common to all the entities (e.g., component, equipment room) defined in this module."; leaf uuid { type yang:uuid; description "Uniquely identifies an entity (e.g., component)."; } leaf name { type string; description "A name for an entity (e.g., component), as specified by a network manager, that provides a non-volatile 'handle' for the entity and that can be modified anytime during the entity lifetime. If no configured value exists, the server MAY set the value of this node to a locally unique value in the operational state."; } leaf description { type string; description "a textual description of inventory object"; } leaf alias { type string; description "a alias name of inventory objects. This alias name can be specified by network manager."; } } grouping network-elements-grouping { description "The attributes of the network elements."; container network-elements { description "The container for the list of network elements."; list network-element { key uuid; description "The list of network elements within the network."; uses common-entity-attributes; container ne-location { description "To be added."; leaf-list equipment-room-name { type leafref { path "/ni:network-inventory/ni:equipment-rooms/" + "ni:equipment-room/ni:name"; } description "Names of equipment rooms where the NE is located. Please note that a NE could be located in several equipment rooms."; } } uses ne-specific-info-grouping; uses components-grouping; } } } grouping ne-specific-info-grouping { description "To be added."; leaf hardware-rev { type string; description "The vendor-specific hardware revision string for the NE."; } leaf firmware-rev { type string; description "The vendor-specific firmware revision string for the NE."; } leaf software-rev { type string; description "The vendor-specific software revision string for the NE."; } leaf mfg-name { type string; description "The name of the manufacturer of this NE"; } leaf mfg-date { type yang:date-and-time; description "The date of manufacturing of the NE."; } leaf part-number { type string; description "The vendor-specific model name identifier string associated with this NE. The preferred value is the customer-visible part number, which may be printed on the NE itself."; } leaf serial-number { type string; description "The vendor-specific serial number string for the NE"; } leaf product-name { type string; description "indicates the vendor-spefic device type infomation."; } } grouping equipment-rooms-grouping { description "The attributes of the equipment rooms."; container equipment-rooms { description "The container for the list of equipment rooms."; list equipment-room { key uuid; description "The list of equipment rooms within the network."; uses common-entity-attributes; leaf location { type string; description "compared with the location information of the other inventory objects, a GIS address is preferred for equipment room"; } container racks { description "To be added."; list rack { key uuid; description "The list of racks within an equipment room."; uses common-entity-attributes; uses rack-specific-info-grouping; list contained-chassis { key "ne-ref component-ref"; description "The list of chassis within a rack."; leaf ne-ref { type leafref { path "/ni:network-inventory/ni:network-elements" + "/ni:network-element/ni:uuid"; } description "The reference to the network element containing the chassis component."; } leaf component-ref { type leafref { path "/ni:network-inventory/ni:network-elements" + "/ni:network-element[ni:uuid" + "=current()/../ne-ref]/ni:components" + "/ni:component/ni:uuid"; } description "The reference to the chassis component within the network element and contained by the rack."; } } } } } } } grouping rack-specific-info-grouping { description "To be added."; container rack-location { description "To be added."; leaf equipment-room-name { type leafref { path "/ni:network-inventory/ni:equipment-rooms" + "/ni:equipment-room/ni:name"; } description "Name of equipment room where this rack is located."; } leaf row-number { type uint32; description "Identifies the row within the equipment room where the rack is located."; } leaf column-number { type uint32; description "Identifies the physical location of the rack within the column."; } } leaf rack-number { type uint32; description "An integer identifier of rack."; } leaf height { type uint16; units millimeter; description "To be added."; } leaf width { type uint16; units millimeter; description "To be added."; } leaf depth { type uint16; units millimeter; description "To be added."; } leaf max-voltage { type uint16; units volt; description "The maximum voltage could be supported by the rack."; } } grouping components-grouping { description "The attributes of the hardware components."; container components { description "The container for the list of components."; list component { key uuid; description "The list of components within a network element."; uses common-entity-attributes; leaf location { type string; description "To be added. In optical transport network, the location string is using the following pattern: '/ne=[/r=][/sh= [/s_sh= ...]][[/sl= [/s_sl= ...]][/p= …]]' "; } leaf class { type identityref { base ianahw:hardware-class; } description "An indication of the general hardware type of the component."; reference "RFC 8348: A YANG Data Model for Hardware Management."; } leaf-list contained-child { type leafref { path "../ni:uuid"; } description "The child components' identifier that are physically contained by this component."; } leaf parent-rel-pos { type int32 { range "0 .. 2147483647"; } description "To be added."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalParentRelPos"; } container parent-references { description "To be added."; leaf equipment-room-uuid { type leafref { path "/ni:network-inventory/ni:equipment-rooms/" + "ni:equipment-room/ni:uuid"; } description "To be added."; } leaf ne-uuid { type leafref { path "/ni:network-inventory/ni:network-elements/" + "ni:network-element/ni:uuid"; } description "To be added."; } leaf rack-uuid { type leafref { path "/ni:network-inventory/ni:equipment-rooms/" + "ni:equipment-room/ni:racks/ni:rack/ni:uuid"; } description "To be added."; } container component-references { description "To be added."; list component-reference { key index; description "this list object is used to indicate its hierarchial parent components' identifier. This hierarchial relation can be found by index parameter. The topest parent component should be 0-index."; leaf index { type uint8; description "To be added."; } leaf class { type leafref { path "../../../../ni:class"; } description "To be added."; } leaf uuid { type leafref { path "../../../../ni:uuid"; } description "To be added."; } } } } 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 firmware-rev { type string; description "The vendor-specific firmware revision string for the component."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalFirmwareRev"; } leaf software-rev { type string; description "The vendor-specific software revision string for the component."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalSoftwareRev"; } leaf serial-num { type string; description "The vendor-specific serial number string for the component. The preferred value is the serial number string actually printed on the component itself (if present)."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalSerialNum"; } leaf mfg-name { type string; description "The name of the manufacturer of this physical component. The preferred value is the manufacturer name string actually printed on the component itself (if present). Note that comparisons between instances of the 'model-name', 'firmware-rev', 'software-rev', and 'serial-num' nodes are only meaningful amongst components with the same value of 'mfg-name'. If the manufacturer name string associated with the physical component is unknown to the server, then this node is not instantiated."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalMfgName"; } leaf part-number { type string; description "The vendor-specific model name identifier string associated with this physical component. The preferred value is the customer-visible part number, which may be printed on the component itself. If the model name string associated with the physical component is unknown to the server, then this node is not instantiated."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalModelName"; } leaf asset-id { type string; description "This node is a user-assigned asset tracking identifier for the component. 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 mfg-date { type yang:date-and-time; description "The date of manufacturing of the managed component."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalMfgDate"; } leaf-list uri { type inet:uri; description "This node contains identification information about the component."; reference "RFC 6933: Entity MIB (Version 4) - entPhysicalUris"; } uses component-specific-info-grouping; } } } grouping component-specific-info-grouping { description "In case if there are some missing attributes of component not defined by RFC8348. These attributes could be component-specific. Here we provide a extension structure for all the components we recognized. We will enrich these component specifc containers in the future."; choice component-class { description "To be added."; case chassis { when "./class = 'ianahw:chassis'"; container chassis-specific-info { description "This container contains some attributes belong to chassis only."; uses chassis-specific-info-grouping; } } case container { when "./class = 'ianahw:container'"; container slot-specific-info { description "This container contains some attributes belong to slot or sub-slot only."; uses slot-specific-info-grouping; } } case module { when "./ni:class = 'ianahw:module'"; container board-specific-info { description "This container contains some attributes belong to board only."; uses board-specific-info-grouping; } } case port { when "./ni:class = 'ianahw:port'"; container port-specific-info { description "This container contains some attributes belong to port only."; uses port-specific-info-grouping; } } //TO BE ADDED: transceiver } } grouping chassis-specific-info-grouping { //To be enriched in the future. description "To be added."; } grouping slot-specific-info-grouping { //To be enriched in the future. description "To be added."; } grouping board-specific-info-grouping { //To be enriched in the future. description "To be added."; } grouping port-specific-info-grouping { //To be enriched in the future. description "To be added."; } } ]]>

Manageability Considerations <Add any manageability considerations>

Security Considerations <Add any security considerations>

IANA Considerations <Add any IANA considerations>

TM Forum (TMF) 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. 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] 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. 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 introduces a collection of common data types to be used with the YANG data modeling language. This document obsoletes RFC 6021. Open Networking Foundation (ONF) TIM Vodafone Huawei Old Dog Consulting Ericsson This document considers the applicability of Abstraction and Control of TE Networks (ACTN) architecture to Packet Optical Integration (POI)in the context of IP/MPLS and optical internetworking. It identifies the YANG data models being defined by the IETF to support this deployment architecture and specific scenarios relevant for Service Providers. Existing IETF protocols and data models are identified for each multi-layer (packet over optical) scenario with a specific focus on the MPI (Multi-Domain Service Coordinator to Provisioning Network Controllers Interface)in the ACTN architecture. 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.

Acknowledgments The authors of this document would like to thank the authors of for having identified the gap and requirements to trigger this work. This document was prepared using kramdown.