Network Inventory YANG B. Wu, Ed. Internet-Draft Huawei Intended status: Standards Track M. Boucadair Expires: 23 April 2026 Orange C. Zhou China Mobile Q. Wu Huawei 20 October 2025 A YANG Network Data Model for Inventory Topology Mapping draft-ietf-ivy-network-inventory-topology-05 Abstract 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 This note is to be removed before publishing as an RFC. Discussion of this document takes place on the Network Inventory YANG Working Group mailing list (inventory-yang@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/inventory-yang/. Source for this draft and an issue tracker can be found at https://github.com/ietf-ivy-wg/network-inventory-topology. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." Wu, et al. Expires 23 April 2026 [Page 1] Internet-Draft Inventory Topology Mapping October 2025 This Internet-Draft will expire on 23 April 2026. Copyright Notice Copyright (c) 2025 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Editorial Note (To be removed by RFC Editor) . . . . . . 3 2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3 3. Sample Use Cases of the Data Model . . . . . . . . . . . . . 3 3.1. Determine Available Resources of Service Attachment Points (SAPs) . . . . . . . . . . . . . . . . . . . . . . . . . 4 3.2. "What-if" Scenarios . . . . . . . . . . . . . . . . . . . 4 4. Module Tree Structure . . . . . . . . . . . . . . . . . . . . 5 4.1. Cable-Level Extensions: cable-name and link-type . . . . 6 4.2. Port-Breakout Capability . . . . . . . . . . . . . . . . 6 5. Network Inventory Topology YANG Module . . . . . . . . . . . 7 6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 8.1. Normative References . . . . . . . . . . . . . . . . . . 12 8.2. Informative References . . . . . . . . . . . . . . . . . 13 Appendix A. "cable-name and "link-type" Usage Examples . . . . . 15 Appendix B. JSON Example of an MPO Breakout-Channel Port . . . . 15 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 16 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 1. Introduction [I-D.ietf-ivy-network-inventory-yang] 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 Wu, et al. Expires 23 April 2026 [Page 2] Internet-Draft Inventory Topology Mapping October 2025 Operating System (OS), software-modules, bios, or boot- loader [I-D.ietf-ivy-network-inventory-software]. In order to ease navigation from (or to) inventory and network topologies, this document extends the network topology data model [RFC8345] for network inventory mapping: "ietf-network-inventory- topology" (Section 5). 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)" [RFC9408], "A YANG Data Model for Layer 2 Network Topologies" [RFC8944], and "A YANG Data Model for Layer 3 Topologies" [RFC8346]. Similar to the base inventory data model [I-D.ietf-ivy-network-inventory-yang], 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. 1.1. 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 * AAAA --> the assigned RFC number for [I-D.ietf-ivy-network-inventory-yang] 2. Conventions and Definitions The meanings of the symbols in the YANG tree diagrams are defined in [RFC8340]. This document uses terms defined in [I-D.ietf-ivy-network-inventory-yang]. 3. Sample Use Cases of the Data Model Wu, et al. Expires 23 April 2026 [Page 3] Internet-Draft Inventory Topology Mapping October 2025 3.1. 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. Figure 1 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. +-----------------+ | Customer | +--------+--------+ Customer Service Models | (e.g., L3SM, L2SM) | +--------+--------+ | Service | | Orchestration | +------+---+------+ | | SAP Network Model | | Inventory Topology Model +------+---+------+ | Network | | Controller | +--------+--------+ | +---------------------+---------------------+ | Network | +-------------------------------------------+ Figure 1: An Example Usage of Network Inventory Topology 3.2. "What-if" Scenarios [I-D.irtf-nmrg-network-digital-twin-arch] 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. Wu, et al. Expires 23 April 2026 [Page 4] Internet-Draft Inventory Topology Mapping October 2025 The management system can use NDT to build multi-layer topology maps for networks and endpoints with relationship types and dependencies, and identify potential impacts on configuration management information from incidents, problems, and changes. More generally, the inventory topology data model can be used as part of the Service & Infrastructure Maps (SIMAP) [I-D.ietf-nmop-simap-concept]. The inventory topology data model can, for example, be used to emulate several "what-if" scenarios such as the impact of End of Life (EOL) or depletion of a hardware component (chipset) on the network resilience and service availability. 4. Module Tree Structure An overview of the structure of the "ietf-network-inventory-topology" module is shown in Figure 2. module: ietf-network-inventory-topology augment /nw:networks/nw:network/nw:node: +--ro inventory-mapping-attributes {topology-to-inventory-navigate}? +--ro ne-ref? nwi:ne-ref augment /nw:networks/nw:network/nt:link: +--ro inventory-mapping-attributes {topology-to-inventory-navigate}? +--ro cable-name? string +--ro link-type? string augment /nw:networks/nw:network/nw:node/nt:termination-point: +--ro inventory-mapping-attributes {topology-to-inventory-navigate}? +--ro ne-ref? nwi:ne-ref +--ro port-ref? leafref +--ro port-breakout! +--ro breakout-channel* [channel-id] +--ro channel-id uint16 augment /nwi:network-inventory/nwi:network-elements /nwi:network-element: +--ro node-ref? leafref {inventory-to-topology-navigate}? +--ro network-ref? -> /nw:networks/network/network-id {inventory-to-topology-navigate}? Figure 2: 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: Wu, et al. Expires 23 April 2026 [Page 5] Internet-Draft Inventory Topology Mapping October 2025 * 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. Also, the "ietf-network-inventory-topology" module augments the "ietf-network-inventory" to add required references to navigate from the inventory to topologies ('node-ref' and 'network-ref'). 4.1. Cable-Level Extensions: cable-name and link-type In order to provide a direct point-to-point cable or fibre between two devices, this document adds lightweight leaves to the topology link: * cable-name – optional asset identifier for a single physical cable (e.g., "CAB-2025-042"). * link-type – flexible-text hint such as "copper", "single-mode- fibre", "multi-mode-fibre", "coax". When the link is formed by a single physical cable (e.g., one factory-terminated patch cord), both leaves may be populated. If the link is composed of several passive elements (such as jumpers, adapters, patch panels, or splice points), the "cable-name" data node can be omitted, and the controller can derive the full path by traversing the TP → port-ref references and usig a more elaborated passive network inventory. An example of such module is defined [I-D.ygb-ivy-passive-network-inventory] which tracks and manages complex passive paths. 4.2. 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. Wu, et al. Expires 23 April 2026 [Page 6] Internet-Draft Inventory Topology Mapping October 2025 The container breakout-config 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 [RFC8944]. 5. Network Inventory Topology YANG Module This module augments the Network Topology [RFC8345]. This module imports the base network inventory [I-D.ietf-ivy-network-inventory-yang]. file "ietf-network-inventory-topology@2025-10-20.yang" module ietf-network-inventory-topology { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-network-inventory-topology"; prefix nwit; import ietf-network { prefix nw; reference "RFC 8345: A YANG Data Model for Network Topologies, Section 4.1"; } import ietf-network-topology { prefix nt; reference "RFC 8345: A YANG Data Model for Network Topologies, Section 4.2"; } import ietf-network-inventory { prefix nwi; reference Wu, et al. Expires 23 April 2026 [Page 7] Internet-Draft Inventory Topology Mapping October 2025 "RFC AAAA: A YANG Data Model for Network Inventory"; } organization "IETF Network Inventory YANG (ivy) Working Group"; contact "WG Web: WG List: 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) 2025 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 2025-10-20 { description "Initial revision."; reference "RFC XXXX: A Network Data Model for Inventory Topology Mapping"; } /* features */ Wu, et al. Expires 23 April 2026 [Page 8] Internet-Draft Inventory Topology Mapping October 2025 feature inventory-to-topology-navigate { description "Indicates support for navigating from inventory to topology."; } feature topology-to-inventory-navigate { description "Indicates support for navigating from topology to inventory."; } /* Groupings */ /* Node Grouping Feature with 1:1 mapping to NE*/ grouping node-inventory-feature-attributes { description "Network Inventory mapping node scope attributes"; container inventory-mapping-attributes { if-feature "topology-to-inventory-navigate"; config false; description "The container node attributes of Network Inventory mapping."; leaf ne-ref { type nwi:ne-ref; config false; description "1:1 mapping to the Network Element (NE) from which this node is abstracted."; } } } grouping tp-inventory-feature-attributes { description "Network Inventory mapping Termination Point (TP) scope attributes."; container inventory-mapping-attributes { if-feature "topology-to-inventory-navigate"; config false; description "Specifies the TP attributes of Network Inventory mapping."; /* 1:1 mapping to physical port component */ uses nwi:port-ref; // breakout channels (lightweight, per physical port) container port-breakout { presence "When present, it indicates that port breakout is supported."; description Wu, et al. Expires 23 April 2026 [Page 9] Internet-Draft Inventory Topology Mapping October 2025 "Breakout capability of the physical port represented by this TP. One TP = one physical port; channels are listed here."; list breakout-channel { key "channel-id"; description "A single lane or sub-port that the physical port can be partitioned into."; leaf channel-id { type uint16; description "Unique index of the breakout channel within the port."; } } // breakout-channel } // port-breakout } } grouping link-inventory-feature-attributes { description "Network Inventory mapping link scope attributes."; container inventory-mapping-attributes { if-feature "topology-to-inventory-navigate"; config false; description "Specifies the link attributes of network inventory mapping."; leaf cable-name { type string; config false; description "Reports the reference of the cable inventory from which this link is abstracted."; } leaf link-type { type string; config false; description "Reports the type of the link."; } } } /* Main blocks */ augment "/nw:networks/nw:network/nw:node" { description "Groups parameters for inventory at the node level."; Wu, et al. Expires 23 April 2026 [Page 10] Internet-Draft Inventory Topology Mapping October 2025 uses node-inventory-feature-attributes; } augment "/nw:networks/nw:network/nt:link" { description "Augments inventory topology link information."; uses link-inventory-feature-attributes; } augment "/nw:networks/nw:network/nw:node/nt:termination-point" { description "Augments inventory termination point information."; uses tp-inventory-feature-attributes; } /* Augment the network-inventory to add topology navigate */ augment "/nwi:network-inventory/nwi:network-elements" + "/nwi:network-element" { if-feature "inventory-to-topology-navigate"; description "Augments the network element with 1:1 mapping with the network the element is part of."; uses nw:node-ref; } } 6. Security Considerations This section is modeled after the template described in Section 3.7 of [I-D.ietf-netmod-rfc8407bis]. 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 [RFC6241] and RESTCONF [RFC8040]. These YANG-based management (1) have to use a secure transport layer (e.g., SSH [RFC4252], TLS [RFC8446], and QUIC {{?RFC9000]) and (2) have to use mutual authentication. The Network Configuration Access Control Model (NACM) [RFC8341] provides the means to restrict access for particular NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. No writable data nodes are defined in this module; all nodes are read-only ("config false"). Wu, et al. Expires 23 April 2026 [Page 11] Internet-Draft Inventory Topology Mapping October 2025 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 reference may be used to track the set of network elements. 7. IANA Considerations IANA is requested to register the following URI in the "ns" subregistry within the "IETF XML Registry" [RFC3688]: URI: urn:ietf:params:xml:ns:yang:ietf-network-inventory-topology Registrant Contact: The IESG. XML: N/A; the requested URI is an XML namespace. IANA is requested to register the following YANG module in the "YANG Module Names" registry [RFC6020] within the "YANG Parameters" registry group: Name: ietf-network-inventory-topology Namespace: urn:ietf:params:xml:ns:yang:ietf-network-inventory-topology Prefix: nwit Maintained by IANA? N Reference: RFC XXXX 8. References 8.1. Normative References [I-D.ietf-ivy-network-inventory-yang] Yu, C., Belotti, S., Bouquier, J., Peruzzini, F., and P. Bedard, "A Base YANG Data Model for Network Inventory", Work in Progress, Internet-Draft, draft-ietf-ivy-network- inventory-yang-11, 14 October 2025, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . Wu, et al. Expires 23 April 2026 [Page 12] Internet-Draft Inventory Topology Mapping October 2025 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . [RFC8345] Clemm, A., Medved, J., Varga, R., Bahadur, N., Ananthakrishnan, H., and X. Liu, "A YANG Data Model for Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March 2018, . [RFC9408] Boucadair, M., Ed., Gonzalez de Dios, O., Barguil, S., Wu, Q., and V. Lopez, "A YANG Network Data Model for Service Attachment Points (SAPs)", RFC 9408, DOI 10.17487/RFC9408, June 2023, . 8.2. Informative References [I-D.ietf-ivy-network-inventory-software] Wu, B., Zhou, C., Wu, Q., and M. Boucadair, "A YANG Network Data Model of Network Inventory Software Extensions", Work in Progress, Internet-Draft, draft-ietf- ivy-network-inventory-software-01, 10 June 2025, . [I-D.ietf-netmod-rfc8407bis] Bierman, A., Boucadair, M., and Q. Wu, "Guidelines for Authors and Reviewers of Documents Containing YANG Data Models", Work in Progress, Internet-Draft, draft-ietf- netmod-rfc8407bis-28, 5 June 2025, . [I-D.ietf-nmop-simap-concept] Havel, O., Claise, B., de Dios, O. G., and T. Graf, "SIMAP: Concept, Requirements, and Use Cases", Work in Progress, Internet-Draft, draft-ietf-nmop-simap-concept- 07, 18 October 2025, . Wu, et al. Expires 23 April 2026 [Page 13] Internet-Draft Inventory Topology Mapping October 2025 [I-D.irtf-nmrg-network-digital-twin-arch] Zhou, C., Yang, H., Duan, X., Lopez, D., Pastor, A., Wu, Q., Boucadair, M., and C. Jacquenet, "Network Digital Twin: Concepts and Reference Architecture", Work in Progress, Internet-Draft, draft-irtf-nmrg-network-digital- twin-arch-11, 6 July 2025, . [I-D.ygb-ivy-passive-network-inventory] Yu, C., Guo, A., Busi, I., Boroon, M., Belotti, S., van caenegem, T., S., S. 1., B., S., Davis, N., Tilocca, M., Peters, B., Yoon, B. Y., LIUYUCONG, Zhao, Y., and A. Sakalabhaktula, "A YANG Data Model for Passive Network Inventory", Work in Progress, Internet-Draft, draft-ygb- ivy-passive-network-inventory-02, 7 July 2025, . [RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH) Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252, January 2006, . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . [RFC7951] Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, August 2016, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8346] Clemm, A., Medved, J., Varga, R., Liu, X., Ananthakrishnan, H., and N. Bahadur, "A YANG Data Model for Layer 3 Topologies", RFC 8346, DOI 10.17487/RFC8346, March 2018, . [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . Wu, et al. Expires 23 April 2026 [Page 14] Internet-Draft Inventory Topology Mapping October 2025 [RFC8944] Dong, J., Wei, X., Wu, Q., Boucadair, M., and A. Liu, "A YANG Data Model for Layer 2 Network Topologies", RFC 8944, DOI 10.17487/RFC8944, November 2020, . Appendix A. "cable-name and "link-type" Usage Examples This appendix illustrates when to populate the link-level "cable- name" and "link-type" data nodes and when to rely on "ietf-passive- inventory" module for multi-segment passive paths. * Direct Point-to-Point Cable Topology: [TP-A] ——— 3 m duplex fibre ——— [TP-B] The link is realised by exactly one cable stock-keeping unit. "cable- name" is filled with the operator's asset tag; "link-type" is set to "fiber". * Three-Segment Passive Path of Fiber Distribution Terminal (FDT) Topology: [TP-A] —— FDT-1 —— segment —— FDT-2 —— [TP-B] The link spans two FDTs and one cable segment (no active inventory). "cable-name" is omitted; the controller derives the complete passive path by: 1. Retrieving "port-ref" of TP-A and TP-B. 2. Walking the passive-inventory relationships (FDT-1 ↔ cable ↔ FDT- 2). Appendix B. 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 [RFC7951] of the "port-breakout" container for this port. =============== NOTE: '' line wrapping per RFC 8792 ================ { "ietf-network-topology:networks": { "network": [ { "network-id": "example:underlay-topology-400g", "node": [ { "node-id": "example:n1", "termination-point": [ { "tp-id": "example:400g-1/0/1", "ietf-network-inventory-topology:inventory-mapping-\ attributes": { Wu, et al. Expires 23 April 2026 [Page 15] Internet-Draft Inventory Topology Mapping October 2025 "ne-ref": "example:NE-1", "port-ref": "example:port-1", "port- breakout": { "breakout-channel": [ { "channel-id": 1 }, { "channel- id": 2 }, { "channel-id": 3 }, { "channel-id": 4 } ] } } } ] } ] } ] } } 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 Chaode Yu Huawei Email: yuchaode@huawei.com Authors' Addresses Bo Wu (editor) Huawei Email: lana.wubo@huawei.com Mohamed Boucadair Orange Email: mohamed.boucadair@orange.com Cheng Zhou China Mobile Email: zhouchengyjy@chinamobile.com Qin Wu Huawei Email: bill.wu@huawei.com Wu, et al. Expires 23 April 2026 [Page 16]