CCAMP Working Group I. Busi Internet-Draft Huawei Technologies Intended status: Standards Track A. Guo Expires: 28 November 2026 Futurewei Technologies S. Belotti Nokia 27 May 2026 A YANG Data Model for requesting Path Computation in an Optical Transport Network (OTN) draft-ietf-ccamp-otn-path-computation-yang-08 Abstract This document provides a mechanism to request path computation in an Optical Transport Network (OTN) by augmenting the Remote Procedure Calls (RPCs) defined in RFC YYYY. About This Document This note is to be removed before publishing as an RFC. The latest revision of this draft can be found at https://ietf-ccamp- wg.github.io/ietf-ccamp-otn-path-computation/draft-ietf-ccamp-otn- path-computation-yang.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-ietf-ccamp-otn- path-computation-yang/. Discussion of this document takes place on the Common Control and Measurement Plane Working Group mailing list (mailto:ccamp@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/ccamp/. Subscribe at https://www.ietf.org/mailman/listinfo/ccamp/. Source for this draft and an issue tracker can be found at https://github.com/ietf-ccamp-wg/ietf-ccamp-otn-path-computation. 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/. Busi, et al. Expires 28 November 2026 [Page 1] Internet-Draft YANG for OTN Path Computation May 2026 Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on 28 November 2026. Copyright Notice Copyright (c) 2026 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1.1. Editorial Note (To be removed by RFC Editor) . . . . . . 3 1.2. Terminology and Notations . . . . . . . . . . . . . . . . 3 1.3. Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 4 1.4. Prefix in Data Node Names . . . . . . . . . . . . . . . . 4 2. YANG Data Model for OTN Path Computation . . . . . . . . . . 4 2.1. YANG Model Overview . . . . . . . . . . . . . . . . . . . 5 2.2. Bandwidth Augmentation . . . . . . . . . . . . . . . . . 5 2.3. Label Augmentations . . . . . . . . . . . . . . . . . . . 5 3. YANG Model for OTN Path Computation . . . . . . . . . . . . . 5 4. Security Considerations . . . . . . . . . . . . . . . . . . . 12 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 6. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 6.1. Normative References . . . . . . . . . . . . . . . . . . 13 6.2. Informative References . . . . . . . . . . . . . . . . . 14 Appendix A. OTN Path Computation Tree Diagram . . . . . . . . . 15 Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 19 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 19 Contributors . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 20 Busi, et al. Expires 28 November 2026 [Page 2] Internet-Draft YANG for OTN Path Computation May 2026 1. Introduction [I-D.ietf-teas-yang-path-computation] describes key use cases, where a client needs to request underlying SDN controllers for path computation. In some of these use cases, the underlying SDN controller can control an Optical Transport Network (OTN). This document defines a YANG data model, which augment the generic Path Computation RPC defined in [I-D.ietf-teas-yang-path-computation], with OTN technology-specific augmentations required to request path computation to an underlying OTN SDN controller. These models allow a client to delegate path computation tasks to the underlying SDN controller without having to obtain OTN detailed information from the controller and performing feasible path computation itself. 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 * YYYY --> the assigned RFC number for [I-D.ietf-teas-yang-path-computation] * ZZZZ --> the assigned RFC number for [I-D.ietf-ccamp-layer1-types] * KKKK --> the assigned RFC number for [I-D.ietf-teas-yang-te] * 2026-05-19 --> the actual date of the publication of this document 1.2. Terminology and Notations Refer to [I-D.ietf-ccamp-otn-topo-yang] and [I-D.ietf-ccamp-layer1-types] for the OTN specific terms used in this document. The following terms are defined in [RFC7950] and are not redefined here: * client Busi, et al. Expires 28 November 2026 [Page 3] Internet-Draft YANG for OTN Path Computation May 2026 * server * augment * data model * data node The following terms are defined in [RFC6241] and are not redefined here: * configuration data * state data The terminology for describing YANG data models is found in [RFC7950]. 1.3. Tree Diagram A simplified graphical representation of the data model is used in Appendix A of this document. The meaning of the symbols in these diagrams is defined in [RFC8340]. 1.4. 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 Table 1. +==========+===========================+===========+ | Prefix | YANG module | Reference | +==========+===========================+===========+ | l1-types | ietf-layer1-types | [RFCZZZZ] | +----------+---------------------------+-----------+ | te | ietf-te | [RFCKKKK] | +----------+---------------------------+-----------+ | te-pc | ietf-te-path-computation | [RFCYYYY] | +----------+---------------------------+-----------+ | otn-pc | ietf-otn-path-computation | RFCXXXX | +----------+---------------------------+-----------+ Table 1: Prefixes and corresponding YANG modules 2. YANG Data Model for OTN Path Computation Busi, et al. Expires 28 November 2026 [Page 4] Internet-Draft YANG for OTN Path Computation May 2026 2.1. YANG Model Overview The YANG data model for requesting OTN path computation is defined as an augmentation of the generic Path Computation RPC defined in [I-D.ietf-teas-yang-path-computation], as shown in Figure 1. +--------------------------+ TE generic | ietf-te-path-computation | +--------------------------+ ^ | | Augments | +-------------+-------------+ OTN | ietf-otn-path-computation | +---------------------------+ Figure 1: Relationship between OTN and TE path computation models The entities and Traffic Engineering (TE) attributes, such as requested path and tunnel attributes, defined in [I-D.ietf-teas-yang-path-computation], are still applicable when requesting OTN path computation and the models defined in this document only specifies the additional OTN technology-specific attributes/information, using the attributes defined in [I-D.ietf-ccamp-layer1-types]. 2.2. Bandwidth Augmentation The OTN path computation model augments all the occurrences of the te-bandwidth container with the OTN technology-specific attributes using the otn-link-bandwidth and otn-path-bandwidth groupings defined in [I-D.ietf-ccamp-layer1-types]. 2.3. Label Augmentations The OTN path computation model augments all the occurrences of the label-restriction list with OTN technology-specific attributes using the otn-label-range-info grouping defined in [I-D.ietf-ccamp-layer1-types]. Moreover, the model augments all the occurrences of the te-label container with the OTN technology-specific attributes using the otn- label-start-end, otn-label-hop and otn-label-step groupings defined in [I-D.ietf-ccamp-layer1-types]. 3. YANG Model for OTN Path Computation Busi, et al. Expires 28 November 2026 [Page 5] Internet-Draft YANG for OTN Path Computation May 2026 file "ietf-otn-path-computation@2026-05-19.yang" module ietf-otn-path-computation { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-otn-path-computation"; prefix otn-pc; import ietf-te-path-computation { prefix te-pc; reference "RFC YYYY: A YANG Data Model for requesting path computation"; } import ietf-te { prefix te; reference "RFC KKKK: A YANG Data Model for Traffic Engineering Tunnels, Label Switched Paths, and Interfaces"; } import ietf-layer1-types { prefix l1-types; reference "RFC ZZZZ: Common YANG Data Types for Layer 1 Networks"; } organization "IETF CCAMP Working Group"; contact "WG Web: WG List: Editor: Aihua Guo Editor: Italo Busi Editor: Sergio Belotti "; description "This module defines a model for requesting OTN Path Computation. 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 Busi, et al. Expires 28 November 2026 [Page 6] Internet-Draft YANG for OTN Path Computation May 2026 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 2026-05-19 { description "Initial version."; reference "RFC XXXX: A YANG Data Model for requesting Path Computation in an Optical Transport Network (OTN)"; } /* * Data nodes */ /* * Augment TE bandwidth */ augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:te-bandwidth/te-pc:technology" { description "Augment TE bandwidth of the requested path."; case otn { uses l1-types:otn-path-bandwidth; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:tunnel-attributes/te-pc:te-bandwidth/" + "te-pc:technology" { description "Augment TE bandwidth of the requested tunnel attributes."; case otn { uses l1-types:otn-path-bandwidth; } } augment "/te:tunnels-path-compute/te:output/" + "te:path-compute-result/te-pc:response/" + "te-pc:computed-paths-properties/" + "te-pc:computed-path-properties/te-pc:path-properties/" Busi, et al. Expires 28 November 2026 [Page 7] Internet-Draft YANG for OTN Path Computation May 2026 + "te-pc:te-bandwidth/te-pc:technology" { description "Augment TE bandwidth of the computed path properties."; case otn { uses l1-types:otn-path-bandwidth; } } /* * Augment TE label range information */ augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-in-segment/" + "te-pc:label-restrictions/te-pc:label-restriction" { description "Augment TE label range information for the ingress segment of the requested path."; uses l1-types:otn-label-range-info; } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-out-segment/" + "te-pc:label-restrictions/te-pc:label-restriction" { description "Augment TE label range information for the egress segment of the requested path."; uses l1-types:otn-label-range-info; } /* * Augment TE label. */ augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:optimizations/te-pc:algorithm/" + "te-pc:metric/te-pc:optimization-metric/" + "te-pc:explicit-route-exclude-objects/" + "te-pc:route-object-exclude-object/te-pc:type/" + "te-pc:label/te-pc:label-hop/te-pc:te-label/" + "te-pc:technology" { description "Augment TE label hop for the optimization of the explicit route objects excluded by the path computation of the requested path."; case otn { uses l1-types:otn-label-hop; } Busi, et al. Expires 28 November 2026 [Page 8] Internet-Draft YANG for OTN Path Computation May 2026 } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:optimizations/te-pc:algorithm/" + "te-pc:metric/te-pc:optimization-metric/" + "te-pc:explicit-route-include-objects/" + "te-pc:route-object-include-object/te-pc:type/" + "te-pc:label/te-pc:label-hop/te-pc:te-label/" + "te-pc:technology" { description "Augment TE label hop for the optimization of the explicit route objects included by the path computation of the requested path."; case otn { uses l1-types:otn-label-hop; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:explicit-route-objects/" + "te-pc:route-object-exclude-always/" + "te-pc:type/te-pc:label/te-pc:label-hop/te-pc:te-label/" + "te-pc:technology" { description "Augment TE label hop for the explicit route objects always excluded by the path computation of the requested path."; case otn { uses l1-types:otn-label-hop; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:explicit-route-objects/" + "te-pc:route-object-include-exclude/te-pc:type/" + "te-pc:label/te-pc:label-hop/te-pc:te-label/" + "te-pc:technology" { description "Augment TE label hop for the explicit route objects included or excluded by the path computation of the requested path."; case otn { uses l1-types:otn-label-hop; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-in-segment/" + "te-pc:label-restrictions/te-pc:label-restriction/" + "te-pc:label-start/te-pc:te-label/te-pc:technology" { Busi, et al. Expires 28 November 2026 [Page 9] Internet-Draft YANG for OTN Path Computation May 2026 description "Augment TE label range start for the ingress segment of the requested path."; case otn { uses l1-types:otn-label-start-end; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-in-segment/" + "te-pc:label-restrictions/te-pc:label-restriction/" + "te-pc:label-end/te-pc:te-label/te-pc:technology" { description "Augment TE label range end for the ingress segment of the requested path."; case otn { uses l1-types:otn-label-start-end; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-in-segment/" + "te-pc:label-restrictions/te-pc:label-restriction/" + "te-pc:label-step/te-pc:technology" { description "Augment TE label range step for the ingress segment of the requested path."; case otn { uses l1-types:otn-label-step; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-out-segment/" + "te-pc:label-restrictions/te-pc:label-restriction/" + "te-pc:label-start/te-pc:te-label/te-pc:technology" { description "Augment TE label range start for the egress segment of the requested path."; case otn { uses l1-types:otn-label-start-end; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-out-segment/" + "te-pc:label-restrictions/te-pc:label-restriction/" + "te-pc:label-end/te-pc:te-label/te-pc:technology" { Busi, et al. Expires 28 November 2026 [Page 10] Internet-Draft YANG for OTN Path Computation May 2026 description "Augment TE label range end for the egress segment of the requested path."; case otn { uses l1-types:otn-label-start-end; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:path-request/te-pc:path-out-segment/" + "te-pc:label-restrictions/te-pc:label-restriction/" + "te-pc:label-step/te-pc:technology" { description "Augment TE label range end for the egress segment of the requested path."; case otn { uses l1-types:otn-label-step; } } augment "/te:tunnels-path-compute/te:input/te:path-compute-info/" + "te-pc:synchronization/te-pc:exclude-objects/" + "te-pc:excludes/te-pc:type/te-pc:label/te-pc:label-hop/" + "te-pc:te-label/te-pc:technology" { description "Augment TE label hop for the explicit route objects to always exclude from synchronized path computation."; case otn { uses l1-types:otn-label-hop; } } augment "/te:tunnels-path-compute/te:output/" + "te:path-compute-result/te-pc:response/" + "te-pc:computed-paths-properties/" + "te-pc:computed-path-properties/te-pc:path-properties/" + "te-pc:path-route-objects/te-pc:path-route-object/" + "te-pc:type/te-pc:label/" + "te-pc:label-hop/te-pc:te-label/te-pc:technology" { description "Augment TE label hop for the route object of the computed path."; case otn { uses l1-types:otn-label-hop; } } } Busi, et al. Expires 28 November 2026 [Page 11] Internet-Draft YANG for OTN Path Computation May 2026 Figure 2: OTN path computation YANG module 4. Security Considerations This section is modeled after the template described in Section 3.7 of [RFC9907]. The "ietf-otn-path-computation" 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 protocols (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. There are no particularly sensitive RPC or action operations. This YANG module uses groupings from other YANG modules that define nodes that may be considered sensitive or vulnerable in network environments. Refer to the Security Considerations of [I-D.ietf-ccamp-layer1-types] for information as to which nodes may be considered sensitive or vulnerable in network environments. The YANG module defined in this document augments the "tunnels-path- compute" and the "tunnel-actions" RPCs, defined in [I-D.ietf-teas-yang-te] and in [I-D.ietf-teas-yang-path-computation], with OTN technology-specific attributes. The security considerations provided in [I-D.ietf-teas-yang-te] and in [I-D.ietf-teas-yang-path-computation] are also applicable to the YANG module defined in this document. 5. IANA Considerations IANA is requested to register the following URI in the "ns" registry within the "IETF XML Registry" group [RFC3688]: URI: urn:ietf:params:xml:ns:yang:ietf-otn-path-computation 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. Busi, et al. Expires 28 November 2026 [Page 12] Internet-Draft YANG for OTN Path Computation May 2026 Name: ietf-otn-path-computation Maintained by IANA? N Namespace: urn:ietf:params:xml:ns:yang:ietf-otn-path-computation Prefix: otn-pc Reference: RFC XXXX 6. References 6.1. Normative References [I-D.ietf-ccamp-layer1-types] Zheng, H. and I. Busi, "Common YANG Data Types for Layer 1 Networks", Work in Progress, Internet-Draft, draft-ietf- ccamp-layer1-types-18, 23 February 2024, . [I-D.ietf-teas-yang-path-computation] Busi, I., Belotti, S., de Dios, O. G., Sharma, A., and Y. Shi, "A YANG Data Model for requesting path computation", Work in Progress, Internet-Draft, draft-ietf-teas-yang- path-computation-28, 12 May 2026, . [I-D.ietf-teas-yang-te] Saad, T., Gandhi, R., Liu, X., Beeram, V. P., and I. Bryskin, "A YANG Data Model for Traffic Engineering Tunnels, Label Switched Paths, and Interfaces", Work in Progress, Internet-Draft, draft-ietf-teas-yang-te-44, 26 March 2026, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [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, . [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . Busi, et al. Expires 28 November 2026 [Page 13] Internet-Draft YANG for OTN Path Computation May 2026 [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . 6.2. Informative References [I-D.draft-gbb-ccamp-optical-path-computation-yang] Busi, I., Guo, A., and S. Belotti, "YANG Data Models for requesting Path Computation in Optical Networks", Work in Progress, Internet-Draft, draft-gbb-ccamp-optical-path- computation-yang-02, 12 September 2022, . [I-D.ietf-ccamp-otn-topo-yang] Zheng, H., Busi, I., Liu, X., Belotti, S., and O. G. de Dios, "A YANG Data Model for Optical Transport Network Topology", Work in Progress, Internet-Draft, draft-ietf- ccamp-otn-topo-yang-20, 7 November 2024, . [I-D.ietf-teas-actn-poi-applicability] Peruzzini, F., Bouquier, J., Busi, I., King, D., and D. Ceccarelli, "Applicability of Abstraction and Control of Traffic Engineered Networks (ACTN) to Packet Optical Integration (POI)", Work in Progress, Internet-Draft, draft-ietf-teas-actn-poi-applicability-18, 14 March 2026, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH) Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252, January 2006, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . Busi, et al. Expires 28 November 2026 [Page 14] Internet-Draft YANG for OTN Path Computation May 2026 [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . [RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based Multiplexed and Secure Transport", RFC 9000, DOI 10.17487/RFC9000, May 2021, . [RFC9907] Bierman, A., Boucadair, M., Ed., and Q. Wu, "Guidelines for Authors and Reviewers of Documents Containing YANG Data Models", BCP 216, RFC 9907, DOI 10.17487/RFC9907, March 2026, . Appendix A. OTN Path Computation Tree Diagram Figure 3 below shows the tree diagram of the YANG data model defined in module ietf-otn-path-computation.yang. See [RFC8340] for an explanation of the symbols used. The data type of every leaf node is shown near the right end of the corresponding line. module: ietf-otn-path-computation augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:te-bandwidth/te-pc:technology: +--:(otn) +-- otn-bandwidth +-- odu-type? identityref +-- (oduflex-type)? +--:(generic) | +-- nominal-bit-rate union +--:(cbr) | +-- client-type identityref +--:(gfp-n-k) | +-- gfp-n uint8 | +-- gfp-k? gfp-k +--:(flexe-client) | +-- flexe-client flexe-client-rate +--:(flexe-aware) | +-- flexe-aware-n uint16 +--:(packet) +-- opuflex-payload-rate union augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:tunnel-attributes/te-pc:te-bandwidth /te-pc:technology: +--:(otn) +-- otn-bandwidth +-- odu-type? identityref Busi, et al. Expires 28 November 2026 [Page 15] Internet-Draft YANG for OTN Path Computation May 2026 +-- (oduflex-type)? +--:(generic) | +-- nominal-bit-rate union +--:(cbr) | +-- client-type identityref +--:(gfp-n-k) | +-- gfp-n uint8 | +-- gfp-k? gfp-k +--:(flexe-client) | +-- flexe-client flexe-client-rate +--:(flexe-aware) | +-- flexe-aware-n uint16 +--:(packet) +-- opuflex-payload-rate union augment /te:tunnels-path-compute/te:output/te:path-compute-result /te-pc:response/te-pc:computed-paths-properties /te-pc:computed-path-properties/te-pc:path-properties /te-pc:te-bandwidth/te-pc:technology: +--:(otn) +--ro otn-bandwidth +--ro odu-type? identityref +--ro (oduflex-type)? +--:(generic) | +--ro nominal-bit-rate union +--:(cbr) | +--ro client-type identityref +--:(gfp-n-k) | +--ro gfp-n uint8 | +--ro gfp-k? gfp-k +--:(flexe-client) | +--ro flexe-client flexe-client-rate +--:(flexe-aware) | +--ro flexe-aware-n uint16 +--:(packet) +--ro opuflex-payload-rate union augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-in-segment /te-pc:label-restrictions/te-pc:label-restriction: +-- otn-label-range +-- range-type? otn-label-range-type +-- tsg? identityref +-- odu-type-list* identityref +-- priority? uint8 augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-out-segment /te-pc:label-restrictions/te-pc:label-restriction: +-- otn-label-range +-- range-type? otn-label-range-type Busi, et al. Expires 28 November 2026 [Page 16] Internet-Draft YANG for OTN Path Computation May 2026 +-- tsg? identityref +-- odu-type-list* identityref +-- priority? uint8 augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:optimizations/te-pc:algorithm /te-pc:metric/te-pc:optimization-metric /te-pc:explicit-route-exclude-objects /te-pc:route-object-exclude-object/te-pc:type/te-pc:label /te-pc:label-hop/te-pc:te-label/te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- tsg? identityref +-- ts-list? string augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:optimizations/te-pc:algorithm /te-pc:metric/te-pc:optimization-metric /te-pc:explicit-route-include-objects /te-pc:route-object-include-object/te-pc:type/te-pc:label /te-pc:label-hop/te-pc:te-label/te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- tsg? identityref +-- ts-list? string augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:explicit-route-objects /te-pc:route-object-exclude-always/te-pc:type/te-pc:label /te-pc:label-hop/te-pc:te-label/te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- tsg? identityref +-- ts-list? string augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:explicit-route-objects /te-pc:route-object-include-exclude/te-pc:type /te-pc:label/te-pc:label-hop/te-pc:te-label /te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- tsg? identityref +-- ts-list? string augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-in-segment /te-pc:label-restrictions/te-pc:label-restriction /te-pc:label-start/te-pc:te-label/te-pc:technology: Busi, et al. Expires 28 November 2026 [Page 17] Internet-Draft YANG for OTN Path Computation May 2026 +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- ts? otn-ts augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-in-segment /te-pc:label-restrictions/te-pc:label-restriction /te-pc:label-end/te-pc:te-label/te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- ts? otn-ts augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-in-segment /te-pc:label-restrictions/te-pc:label-restriction /te-pc:label-step/te-pc:technology: +--:(otn) +-- otn-label-step +-- tpn? otn-tpn +-- ts? otn-ts augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-out-segment /te-pc:label-restrictions/te-pc:label-restriction /te-pc:label-start/te-pc:te-label/te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- ts? otn-ts augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-out-segment /te-pc:label-restrictions/te-pc:label-restriction /te-pc:label-end/te-pc:te-label/te-pc:technology: +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- ts? otn-ts augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:path-request/te-pc:path-out-segment /te-pc:label-restrictions/te-pc:label-restriction /te-pc:label-step/te-pc:technology: +--:(otn) +-- otn-label-step +-- tpn? otn-tpn +-- ts? otn-ts augment /te:tunnels-path-compute/te:input/te:path-compute-info /te-pc:synchronization/te-pc:exclude-objects /te-pc:excludes/te-pc:type/te-pc:label/te-pc:label-hop /te-pc:te-label/te-pc:technology: Busi, et al. Expires 28 November 2026 [Page 18] Internet-Draft YANG for OTN Path Computation May 2026 +--:(otn) +-- otn-label +-- tpn? otn-tpn +-- tsg? identityref +-- ts-list? string augment /te:tunnels-path-compute/te:output/te:path-compute-result /te-pc:response/te-pc:computed-paths-properties /te-pc:computed-path-properties/te-pc:path-properties /te-pc:path-route-objects/te-pc:path-route-object /te-pc:type/te-pc:label/te-pc:label-hop/te-pc:te-label /te-pc:technology: +--:(otn) +--ro otn-label +--ro tpn? otn-tpn +--ro tsg? identityref +--ro ts-list? string Figure 3: OTN path computation tree diagram Appendix B. Change Log The initial YANG data model requesting path computation in optical networks was draft-gbb-ccamp-optical-path-computation-yang-00. This document included path computation request capabilities for WSON, Flexi-Grid and OTN technologies. However, it was proposed at IETF 113 (March 25, 2022) to split the initial document into separate documents for WDM (WSON and Flexi-Grid) and OTN technologies, as each technology may be developed and implemented separately. The WDM technology capabilities were kept in [I-D.draft-gbb-ccamp-optical-path-computation-yang], and the OTN capabilities were moved into this document. Editors note, please remove this appendix before publication. Acknowledgments The authors of this document would like to thank the authors of [I-D.ietf-teas-actn-poi-applicability] for having identified the gap and requirements to trigger this work. This document was prepared using kramdown. Contributors Daniel King Old Dog Consulting Email: daniel@olddog.co.uk Busi, et al. Expires 28 November 2026 [Page 19] Internet-Draft YANG for OTN Path Computation May 2026 Authors' Addresses Italo Busi Huawei Technologies Email: italo.busi@huawei.com Aihua Guo Futurewei Technologies Email: aihuaguo.ietf@gmail.com Sergio Belotti Nokia Email: sergio.belotti@nokia.com Busi, et al. Expires 28 November 2026 [Page 20]