Internet-Draft Fine grain OTN YANG July 2026
Tan, et al. Expires 30 January 2027 [Page]
Workgroup:
CCAMP Working Group
Internet-Draft:
draft-ietf-ccamp-fgotn-yang-latest
Published:
Intended Status:
Standards Track
Expires:
Authors:
Y. Tan
China Unicom
Y. Zheng
China Unicom
I. Busi
Huawei Technologies
C. Yu
Huawei Technologies
X. Zhao
CAICT

YANG Data Models for fine grain Optical Transport Network

Abstract

This document defines YANG data models to describe the topology and tunnel information of a fine grain Optical Transport Network. The YANG data models defined in this document are designed to meet the requirements for efficient transmission of sub-1Gbit/s client signals in transport network.

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/draft-ietf-ccamp-fgotn-yang/draft-ietf-ccamp-fgotn-yang.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-ietf-ccamp-fgotn-yang/.

Discussion of this document takes place on the CCAMP Working Group 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/draft-ietf-ccamp-fgotn-yang.

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."

This Internet-Draft will expire on 30 January 2027.

▲

Table of Contents

1. Introduction

Optical Transport Networks (OTN) is a mainstream layer 1 technology for the transport network. Over the years, it has continued to evolve, to improve its transport functions for the emerging requirements. The topology and tunnel information in the OTN has already been defined by generic traffic-engineering models and technology-specific models, including [I-D.ietf-ccamp-otn-topo-yang] and [I-D.ietf-ccamp-otn-tunnel-model].

In the latest version of OTN, ITU-T G.709/Y.1331 Edition 6.5 [ITU-T_G.709], the fine grain OTN (fgOTN) is introduced for the efficient transmission of low rate client signals (e.g., sub-1G).

This document presents the control interface requirements of fgOTN, and defines three YANG data models for fgOTN topology, fgOTN tunnel, and fgOTN types. The topology model can capture topological and resource-related information pertaining to fgOTN. The fgOTN tunnel YANG data model defined in this document is used for the provisioning and management of fgOTN Traffic Engineering (TE) tunnels and Label Switched Paths (LSPs). The fgOTN types model contains a collection of YANG data types considered generally useful for fgOTN networks.

Furthermore, this document also imports the generic Layer 1 types defined in [I-D.ietf-ccamp-layer1-types].

The YANG data models defined in this document conform to the Network Management Datastore Architecture (NMDA) defined in [RFC8342].

1.1. Terminology and Notations

Some of the key terms used in this document are listed as follow.

  • fgTS: fine grain Tributary Slot.

  • fgODUflex: fine grain Optical channel Data Unit flex.

The following terms are defined in [RFC7950] and are not redefined here:

  • client

  • 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].

1.2. Tree Diagram

A simplified graphical representation of the data model is used in Section 7 of this document. The meaning of the symbols in this diagram is defined in [RFC8340].

1.3. Requirements Language

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 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here.

1.4. Prefixes in Model Names

In this documents, 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.

Table 1: Prefixes and corresponding YANG modules
Prefix Yang Module Reference
l1-types ietf-layer1-types [RFC YYYY]
otnt ietf-otn-topology [RFC ZZZZ]
te ietf-te [RFC KKKK]
otn-tnl ietf-otn-tunnel [RFC JJJJ]
fgotnt ietf-fgotn-topology RFC XXXX
fgotn-tnl ietf-fgotn-tunnel RFC XXXX
fgotn-types ietf-fgotn-types RFC XXXX

RFC Editor Note: Please replace XXXX with the number assigned to the RFC once this draft becomes an RFC. Please replace YYYY with the RFC numbers assigned to [I-D.ietf-ccamp-layer1-types]. Please replace ZZZZ with the RFC numbers assigned to [I-D.ietf-ccamp-otn-topo-yang]. Please replace KKKK with the RFC numbers assigned to [I-D.ietf-teas-yang-te]. Please replace JJJJ with the RFC numbers assigned to [I-D.ietf-ccamp-otn-tunnel-model]. Please remove this note.

2. Fine grain Optical Transport Network Scenarios Overview

OTN network will cover a larger scope of networks, it may include the backbone network, metro core, metro aggregation, metro access, and even the OTN CPE in the customers' networks [ITU-T_G.709.20]. In general, the metro OTN networks support both fgODUflex and ODUk switching. At the boundary nodes (e.g., metro-core nodes) of the metro OTN networks, the fgODUflexes to other metro OTN networks are multiplexed into ODUk of backbone networks. Therefore, the backbone OTN network could only support ODUk switching.

The typical scenarios for fgOTN is to provide low bit rate private line or private network services for customers. The interface function requirements of fgOTN mainly include topology resource reporting and service provisioning. Three scenarios that require special consideration are listed based on the characteristics of fgOTN.

2.1. Retrieve Server Tunnels Scenario of fgOTN

Figure 1 below shows an example of scenario to retrieve server tunnels for multi-domain fgOTN service. In this example, some small bandwidth fgOTN service are aggregated by the access ring (10G), and then aggregated into a bigger bandwidth in metro ring (100G). The allocation of TS to support fgOTN switching maybe different in access ring and metro ring. All link bandwidth information that supports fgOTN should be reported to MDSC by the PNC controller. E.g. there could be three ODU0 allocated in the access ring while there could be two ODU2 are allocated in the metro ring to support fgOTN switching. In this example, the server layer ODUk tunnel for fgOTN tunnel from node A to node E is ODU0, and the server layer tunnel from node E to node G is ODU2. The server layer tunnel for fgOTN tunnel will include one ODU0 tunnel and one ODU2 tunnel.

A Domain 1 Domain 2 10G B E G I 100G 100G C F H J 10G D
Figure 1: The Scenario to Retrieve Server Tunnels

2.2. Multi-layer Path Splicing Scenario of fgOTN

Some operators that would like to provide the paths when there could be different switching capabilities of nodes in their LSP, so that the MDSC coordinator can clearly display multi-layer paths and the relationship between primary-path and secondary-path. In the current network, not all nodes in the operator network support fgOTN, as shown in figure 2, node f1, f2, f3 and f4 support fgOTN, node N-f5 and node N-f6 do not support fgOTN. To present the end-to-end multi-layer primary-path and secondary-path of the services on the client side, it is necessary to complete the end-to-end path splicing based on the the ODU tunnel information associated with the fgotn tunnel.

In Figure 2, assuming that the server layer ODUk tunnel for the fgOTN primary tunnel from node f1 to node f2 is ODU0, the server layer tunnel from node f2 to node f3 is ODU2, and the server layer tunnel from node f3 to node f4 is ODU1. Assuming the server layer ODUk tunnel for the fgOTN secondary tunnel from node f1 to node f2 is ODU2. We need to setup four server layer ODUk tunnels before setting up an fgODUflex tunnel with a primary path and a secondary path to provide protection. To support multi-layer path splicing, we should make some extension on the dependency tunnel structure or on the path element, such as extending the working roles and index of the tunnels.

f2 f3 primary-path f1 f4 secondary-path N-f5 N-f6
Figure 2: Multi-layer Path Splicing Scenario of fgOTN

2.3. Hitless Bandwidth Adjustment Scenario of fgOTN

[ITU-T_G.709] defines the data plane procedure to support fgODUflex hitless resizing. The support of management of hitless resizing of fgODUflex needs to be carefully considered.

The range of fgOTN service's Bandwidth on Demand (BoD) cannot exceed its server layer's bandwidth.

The client needs to know how many bandwidth of a link is allocated for fgOTN. When performs hitless resizing, the client sends the fgODUflex identifier and the target bandwidth to the source node controller. After receiving the network management configuration information, the source node triggers the bandwidth adjustment. During the hitless bandwidth adjustment process, it is necessary to reserve or mark the corresponding bandwidth resources first, and then trigger the bandwidth adjustment actions.

Another point to note is that when performing bidirectional hitless resizing for fgODUflex service, the adjustment should be initiated by the client side to a single network management system. Specifically, the adjustment is first performed in the Node 1 to Node 6 direction, and then the reverse direction (Node 6 to Node 1) is automatically triggered for adjustment. For bidirectional hitless resizing, the adjustment shall be regarded as successful only when both directions are completed. If only one direction succeeds while the other fails, the controller may issue a command to perform forced bandwidth adjustment to ensure consistent status in both directions (which may be hit-impairing).

When 1+1 protection is configured for fgODUflex, if hitless bandwidth adjustment is performed on fgODUflex, both the working path and the protection path shall initiate the adjustment protocol and signaling transmission. Each node shall check the signaling delivered by both the working path and the protection path simultaneously during state processing.

Both single domain and multi-domain hitless resizing should be supported. For single domain and multi-domain hitless resizing scenario, the source controller alone report the bandwidth adjustment status to the MDSC coordinator upon completion.

MDSC Controller Controller Controller 1 2 3 End-to-end fgOTN service node node node node node node 1 2 3 4 5 6 source destination Domain 1 Domain 2 Domain 3
Figure 3: Hitless Resizing Scenario of fgOTN

3. YANG Data Model for fine grain Optical Transport Network Overview

In order to provide fgOTN capabilities, this document defines two extension YANG data models augmenting to OTN topology and OTN tunnel YANG model, as defined in [I-D.ietf-ccamp-otn-topo-yang] and [I-D.ietf-ccamp-otn-tunnel-model].

As defined in Annex M of [ITU-T_G.709], fgOTN is defining a new path layer network which complements the existing OTN. Therefore:

In other words, the same switching-capability and encoding types can be used for ODUk and fgODUflex. Accordingly, additional parameters are required to identify fgODUflex tunnels. This document defines a new YANG module ietf-fgotn-types containing fgOTN-specific type definitions. In order to identify the fgODUflex tunnel, a new identity fgODUflex based on the odu-type in [I-D.ietf-ccamp-layer1-types] is defined in ietf-fgotn-types YANG module.

4. YANG Data Model for fgOTN Topology

4.1. Fine Grain OTN Topology Data Model Overview

This document aims to describe the data model for fine grain OTN topology. The YANG module presented in this document augments from OTN topology data model, i.e., the ietf-otn-topology, as specified in [I-D.ietf-ccamp-otn-topo-yang]. In section 6 of [I-D.ietf-ccamp-otn-topo-yang], the guideline for augmenting OTN topology model was provided, and in this draft, we augment the OTN topology model to describe the topology characteristics of fgOTN.

Common types, identities and groupings defined in [I-D.ietf-ccamp-layer1-types] is reused in this document.

[RFC8345] defines an abstract (generic, or base) YANG data model for network/service topologies and inventories, and provides the fundamental model for [RFC8795]. OTN topology module in [I-D.ietf-ccamp-otn-topo-yang] augments from the TE topology YANG model defined in [RFC8795]. Figure 4 shows the augmentation relationship.

ietf-network ietf-network-topology Augments ietf-te-topology Augments ietf-otn-topology Augments ietf-fgotn-topology
Figure 4: Relationship between fgOTN topology and OTN topology model

The entities, TE attributes and OTN attributes, such as nodes, termination points and links, are still applicable for describing an fgOTN topology and the model presented in this document only specifies technology-specific attributes/information. The fgOTN-specific attributes including the fgTS, can be used to represent the bandwidth and label information. At the same time, it is necessary to extend the encoding and switching-capability enumeration values in [I-D.ietf-teas-rfc8776-update] to identify that the current Tunnel Termination Point (TTP) is a termination point of an fgOTN tunnel.

4.2. Bandwidth Augmentation

Building upon the OTN topology model, the odu-list structure within the OTN topology YANG module is leveraged to represent the maximum link bandwidth and unreserved bandwidth for fgOTN. As an illustration, if an OTU2 port supports fgOTN, fgOTN is enabled across the entire port. In this case, the odu-type shall be set to ietf-fgotn-types:fgODUflex, with the associated number equal to 952. When a portion of fgts on the port is occupied, the value of maximum link bandwidth remains unchanged, while the number representing available bandwidth decreases accordingly.

  "ietf-otn-topology:odulist": [{
    "odu-type": "ietf-fgotn-types:fgODUflex",
    "number": 952
  }]

4.3. Label Augmentation

The model augments the label-restriction list with fgOTN technology-specific label information using the otn-label-range-info grouping defined in [I-D.ietf-ccamp-layer1-types].

  augment /nw:networks/tet:te/tet:templates/tet:link-template
          /tet:te-link-attributes/tet:label-restrictions
          /tet:label-restriction:
    +--rw fgts-range* [odu-type odu-ts-number]
        +--rw odu-type           identityref
        +--rw odu-ts-number?     fgotnt:ts-list
        +--rw fgts-reserved?     fgotnt:ts-list
        +--rw fgts-unreserved?   fgotnt:ts-list

The fgts-range list is used to describe the availability of fgOTN timeslot in the server ODUk, including the fgts-reserved and fgts-unreserved. The odu-ts-number is used to indicate the index of server ODUk channel.

5. YANG Data Model for fgOTN Tunnel

5.1. Fine Grain OTN Tunnel Data Model Overview

This document aims to describe the data model for fgOTN tunnel. The fgOTN tunnel model augments to OTN tunnel [I-D.ietf-ccamp-otn-tunnel-model] with fgOTN-specific parameters, including the bandwidth information and label information. Figure 5 shows the augmentation relationship.

ietf-te Augments ietf-otn-tunnel Augments ietf-fgotn-tunnel
Figure 5: Relationship between fgOTN and OTN tunnel model

It's also worth noting that the fgOTN tunnel provisioning is usually based on the fgOTN topology. Therefore the fgOTN tunnel model is usually used together with fgOTN topology model specified in this document. The OTN tunnel model also imports a few type modules, including ietf-layer1-types and ietf-te-types.

A new identity based on odu-type should be defined in fgotn-types yang module to indicate the fgODUflex tunnel.

5.2. Bandwidth Augmentation

The model augment TE bandwidth information of fgOTN tunnel.

  augment /te:te/te:tunnels/te:tunnel/te:te-bandwidth/te:technology
          /otn-tnl:otn/otn-tnl:otn-bandwidth:
    +--rw fgoduflex-bandwidth?   string

The string value fgoduflex-bandwidth is used to indicate the bandwidth of this fgOTN tunnel.

5.3. Label Augmentation

The module augments TE label-hop for the explicit route objects included or excluded by the path computation of the primary-paths and secondary-paths using the fgts-numbers. The fgts-numbers is used to specify fgTS information on inter-domain ports of the routing path. When specifying the fgotn time slot in the routing constraint information, the ODU time slot must also be specified. We also augment the TE label-hop for the record route of the LSP using the fgts-numbers.

6. YANG Data Model for fgOTN types 

<CODE BEGINS> file "ietf-fgotn-types@2026-02-27.yang"

module ietf-fgotn-types {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-fgotn-types";
  prefix fgotn-types;

  import ietf-layer1-types {
    prefix l1-types;
    reference
      "This module defines Layer 1 YANG types.";
  }

  /* Note: The RFC Editor will replace YYYY with the number assigned
     to the RFC once draft-ietf-ccamp-layer1-types becomes an RFC.*/

  organization
    "Internet Engineering Task Force (IETF) CCAMP WG";
  contact
    "
      ID-draft editor:
        Yanxia Tan (tanyx11@chinaunicom.cn);
        Yanlei Zheng (zhengyanlei@chinaunicom.cn);
        Italo Busi (italo.busi@huawei.com);
        Chaode Yu (yuchaode@huawei.com);
        Xing Zhao (zhaoxing@caict.ac.cn);
    ";
  description
    "This module contains a collection of YANG data types considered
     generally useful for fine grain Optical Transport Network
     (fgOTN) networks.

     Copyright (c) 2026 IETF Trust and the persons
     identified as authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Revised BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // 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 2026-02-27 {
    description
      "initial version";
    reference
      "RFC XXXX: YANG Data Models for fine grain Optical Transport
                 Network";
  }

  identity fgODUflex {
    base l1-types:odu-type;
    description
      "fgODUflex type (fine grain flexible bit rate, resizable).";
  }
}

<CODE ENDS>
Figure 6: fgOTN types YANG module

7. YANG Tree for fgOTN topology

Figure 7 below shows the tree diagram of the YANG data model defined in module "ietf-fgotn-topology" (Figure 8).

module: ietf-fgotn-topology

  augment /nw:networks/nw:network/nt:link/tet:te
            /tet:te-link-attributes/tet:label-restrictions
            /tet:label-restriction:
    +--rw fgts-range* [odu-type odu-ts-number]
       +--rw odu-type           identityref
       +--rw odu-ts-number      fgotnt:ts-list
       +--rw fgts-reserved?     fgotnt:ts-list
       +--rw fgts-unreserved?   fgotnt:ts-list
Figure 7

8. YANG Data Model for fgOTN topology 

<CODE BEGINS> file "ietf-fgotn-topology@2026-07-23.yang"

module ietf-fgotn-topology {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-fgotn-topology";
  prefix fgotnt;

  import ietf-network {
    prefix nw;
    reference
      "RFC8345: A YANG Data Model for Network Topologies";
  }
  import ietf-network-topology {
    prefix nt;
    reference
      "RFC8345: A YANG Data Model for Network Topologies";
  }
  import ietf-te-topology {
    prefix tet;
    reference
      "RFC 8795: YANG Data Model for Traffic Engineering (TE)
                 Topologies";
  }
  import ietf-layer1-types {
    prefix l1-types;
    reference
      "RFC YYYY: A YANG Data Model for Layer 1 Types";
  }

  /* Note: The RFC Editor will replace YYYY with the number assigned
     to the RFC once draft-ietf-ccamp-layer1-types becomes an RFC.*/

  import ietf-otn-topology {
    prefix otnt;
    reference
      "RFC ZZZZ: A YANG Data Model for Optical Transport Network
                 Topology";
  }

  /* Note: The RFC Editor will replace ZZZZ with the number assigned
     to the RFC once draft-ietf-ccamp-otn-topo-yang becomes an RFC.*/

  organization
    "Internet Engineering Task Force (IETF) CCAMP WG";
  contact
    "
      ID-draft editor:
        Yanxia Tan (tanyx11@chinaunicom.cn);
        Yanlei Zheng (zhengyanlei@chinaunicom.cn);
        Italo Busi (italo.busi@huawei.com);
        Chaode Yu (yuchaode@huawei.com);
        Xing Zhao (zhaoxing@caict.ac.cn);
    ";
  description
    "This module defines a YANG data model for fgOTN-specific
     extension based on existing network topology models. The model
     fully conforms to the Network Management Datastore Architecture
     (NMDA).

     Copyright (c) 2026 IETF Trust and the persons
     identified as authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Revised BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.

     The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL
     NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED',
     'MAY', and 'OPTIONAL' in this document are to be interpreted as
     described in BCP 14 (RFC 2119) (RFC 8174) when, and only when,
     they appear in all capitals, as shown here.";

  // 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 2026-07-23 {
    description
      "initial version";
    reference
      "RFC XXXX: YANG Data Models for fine grain Optical Transport
                 Network";
  }

  typedef ts-list {
    type string {
      pattern '([1-9][0-9]{0,3}(-[1-9][0-9]{0,3})?'
            + '(,[1-9][0-9]{0,3}(-[1-9][0-9]{0,3})?)*)?';
    }
    description
      "A list of Tributary Slots (TS) ranging between 1 and 4095.

       If multiple values or ranges are given, they all MUST be
       disjoint and MUST be in ascending order.

       For example 1-20,25,50-1000.";
    reference
      "RFC 7139: GMPLS Signaling Extensions for Control
                 of Evolving G.709 Optical Transport Networks";
  }

  augment "/nw:networks/nw:network/nt:link/tet:te"
        + "/tet:te-link-attributes/tet:label-restrictions"
        + "/tet:label-restriction" {
    when "./otnt:otn-label-range/otnt:range-type = 'trib-slot'" {
      description
        "Valid only when range-type represented by trib-slot.";
    }
    description
      "specific augmentation of fgOTN label";
    list fgts-range {
      key "odu-type odu-ts-number";
      description
        "This structure is used to describe the availability of
         fgOTN timeslot in the server ODUk";
      leaf odu-type {
        type identityref {
          base l1-types:odu-type;
        }
        description
          "The granularity of server ODUk";
      }
      leaf odu-ts-number {
        type fgotnt:ts-list;
        description
          "The index of server ODUk channel";
      }
      leaf fgts-reserved {
        type fgotnt:ts-list;
        description
          "The reserved fgOTN timeslot in this server ODUk";
      }
      leaf fgts-unreserved {
        type fgotnt:ts-list;
        description
          "The unreserved fgOTN timeslot in this server ODUk";
      }
    }
  }
}

<CODE ENDS>
Figure 8: fgOTN topology YANG module

9. YANG Tree for fgOTN tunnel

Figure 9 below shows the tree diagram of the YANG data model defined in module "ietf-fgotn-tunnel" (Figure 10).

module: ietf-fgotn-tunnel

  augment /te:te/te:tunnels/te:tunnel/te:te-bandwidth/te:technology
            /otn-tnl:otn/otn-tnl:otn-bandwidth:
    +--rw fgoduflex-bandwidth?   string
  augment /te:te/te:tunnels/te:tunnel/te:primary-paths
            /te:primary-path/te:explicit-route-objects
            /te:route-object-include-exclude/te:type/te:label
            /te:label-hop/te:te-label/te:technology/otn-tnl:otn
            /otn-tnl:otn-label:
    +--rw fgts-numbers?   string
  augment /te:te/te:tunnels/te:tunnel/te:primary-paths
            /te:primary-path/te:primary-reverse-path
            /te:explicit-route-objects
            /te:route-object-include-exclude/te:type/te:label
            /te:label-hop/te:te-label/te:technology/otn-tnl:otn
            /otn-tnl:otn-label:
    +--rw fgts-numbers?   string
  augment /te:te/te:tunnels/te:tunnel/te:secondary-paths
            /te:secondary-path/te:explicit-route-objects
            /te:route-object-include-exclude/te:type/te:label
            /te:label-hop/te:te-label/te:technology/otn-tnl:otn
            /otn-tnl:otn-label:
    +--rw fgts-numbers?   string
  augment /te:te/te:tunnels/te:tunnel/te:secondary-reverse-paths
            /te:secondary-reverse-path/te:explicit-route-objects
            /te:route-object-include-exclude/te:type/te:label
            /te:label-hop/te:te-label/te:technology/otn-tnl:otn
            /otn-tnl:otn-label:
    +--rw fgts-numbers?   string
  augment /te:te/te:lsps/te:lsp/te:lsp-actual-route-information
            /te:lsp-actual-route-information/te:type/te:label
            /te:label-hop/te:te-label/te:technology/otn-tnl:otn
            /otn-tnl:otn-label:
    +--ro fgts-numbers?   string
Figure 9

10. YANG Data Model for fgOTN tunnel 

<CODE BEGINS> file "ietf-fgotn-tunnel@2026-02-27.yang"

module ietf-fgotn-tunnel {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-fgotn-tunnel";
  prefix fgotn-tnl;

  import ietf-te {
    prefix te;
    reference
      "RFC KKKK: A YANG Data Model for Traffic Engineering Tunnels,
                 Label Switched Paths and Interfaces";
  }
  import ietf-fgotn-types {
    prefix fgotn-types;
    reference
      "RFC XXXX: YANG Data Models for fine grain Optical Transport
       Network";
  }

  /* Note: The RFC Editor will replace KKKK with the number assigned
     to the RFC once draft-ietf-teas-yang-te becomes an RFC.*/

  import ietf-otn-tunnel {
    prefix otn-tnl;
    reference
      "RFC JJJJ: OTN Tunnel YANG Model";
  }

  /* Note: The RFC Editor will replace JJJJ with the number assigned
     to the RFC once draft-ietf-ccamp-otn-tunnel-model becomes
     an RFC.*/

  organization
    "Internet Engineering Task Force (IETF) CCAMP WG";
  contact
    "
      ID-draft editor:
        Yanxia Tan (tanyx11@chinaunicom.cn);
        Yanlei Zheng (zhengyanlei@chinaunicom.cn);
        Italo Busi (italo.busi@huawei.com);
        Chaode Yu (yuchaode@huawei.com);
        Xing Zhao (zhaoxing@caict.ac.cn);
    ";
  description
    "This module defines a YANG data model for fgOTN-specific
     extension based on existing network topology models. The model
     fully conforms to the Network Management Datastore Architecture
     (NMDA).

     Copyright (c) 2026 IETF Trust and the persons
     identified as authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Revised BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  // 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 2026-02-27 {
    description
      "initial version";
    reference
      "RFC XXXX: YANG Data Models for fine grain Optical Transport
                 Network";
  }

  augment "/te:te/te:tunnels/te:tunnel/"
        + "te:te-bandwidth/te:technology/"
        + "otn-tnl:otn/otn-tnl:otn-bandwidth" {
    description
      "augmentation of fgOTN tunnel on bandwidth structure";
    leaf fgoduflex-bandwidth {
      when 'derived-from-or-self(../otn-tnl:odu-type,'
         + '"fgotn-types:fgODUflex")' {
        description
          "Applicable when odu-type is fgODUflex.";
      }
      type string;
      description
        "Augment TE bandwidth of the fgOTN tunnel";
    }
  }

  augment "/te:te/te:tunnels/te:tunnel/"
        + "te:primary-paths/te:primary-path/"
        + "te:explicit-route-objects/"
        + "te:route-object-include-exclude/te:type/te:label/"
        + "te:label-hop/te:te-label/te:technology/otn-tnl:otn"
        + "/otn-tnl:otn-label" {
    description
      "augmentation of fgOTN label";
    leaf fgts-numbers {
      type string;
      description
        "Augment fgOTN timeslot information of this label hop";
    }
  }

  augment "/te:te/te:tunnels/te:tunnel/te:primary-paths"
        + "/te:primary-path/te:primary-reverse-path"
        + "/te:explicit-route-objects"
        + "/te:route-object-include-exclude/te:type/te:label"
        + "/te:label-hop/te:te-label/te:technology/otn-tnl:otn"
        + "/otn-tnl:otn-label" {
    description
      "augmentation of fgOTN label";
    leaf fgts-numbers {
      type string;
      description
        "Augment fgOTN timeslot information of this label hop";
    }
  }

  augment "/te:te/te:tunnels/te:tunnel/te:secondary-paths"
        + "/te:secondary-path/te:explicit-route-objects"
        + "/te:route-object-include-exclude/te:type/te:label"
        + "/te:label-hop/te:te-label/te:technology/otn-tnl:otn"
        + "/otn-tnl:otn-label" {
    description
      "augmentation of fgOTN label";
    leaf fgts-numbers {
      type string;
      description
        "fgOTN timeslot information of this label hop";
    }
  }

  augment "/te:te/te:tunnels/te:tunnel/te:secondary-reverse-paths"
        + "/te:secondary-reverse-path/te:explicit-route-objects"
        + "/te:route-object-include-exclude/te:type/te:label"
        + "/te:label-hop/te:te-label/te:technology/otn-tnl:otn"
        + "/otn-tnl:otn-label" {
    description
      "augmentation of fgOTN label";
    leaf fgts-numbers {
      type string;
      description
        "fgOTN timeslot information of this label hop";
    }
  }

  augment "/te:te/te:lsps/te:lsp/te:lsp-actual-route-information"
        + "/te:lsp-actual-route-information/te:type/te:label"
        + "/te:label-hop/te:te-label/te:technology/otn-tnl:otn"
        + "/otn-tnl:otn-label" {
    description
      "augmentation of fgOTN label";
    leaf fgts-numbers {
      type string;
      description
        "fgOTN timeslot information of this label hop";
    }
  }
}

<CODE ENDS>
Figure 10: fgOTN tunnel YANG module

11. Manageability Considerations

<Add any manageability considerations>

12. Security Considerations

<Add any security considerations>

13. IANA Considerations

<Add any IANA considerations>

14. References

14.1. 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-19, , <https://datatracker.ietf.org/doc/html/draft-ietf-ccamp-layer1-types-19>.
[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-21, , <https://datatracker.ietf.org/doc/html/draft-ietf-ccamp-otn-topo-yang-21>.
[I-D.ietf-ccamp-otn-tunnel-model]
Zheng, H., Busi, I., Belotti, S., Lopez, V., and Y. Xu, "A YANG Data Model for Optical Transport Network (OTN) Tunnels and Label Switched Paths", Work in Progress, Internet-Draft, draft-ietf-ccamp-otn-tunnel-model-25, , <https://datatracker.ietf.org/doc/html/draft-ietf-ccamp-otn-tunnel-model-25>.
[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, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-yang-te-44>.
[ITU-T_G.709]
International Telecommunication Union, "Interfaces for the optical transport network", ITU-T Recommendation G.709, Amendment 3 , , <https://www.itu.int/rec/T-REC-G.709/>.
[ITU-T_G.709.20]
International Telecommunication Union, "Overview of fine grain OTN", ITU-T Recommendation G.709.20, Amendment 1 , , <https://www.itu.int/rec/T-REC-G.709.20/>.
[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/rfc/rfc2119>.
[RFC6241]
Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, , <https://www.rfc-editor.org/rfc/rfc6241>.
[RFC7950]
Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, , <https://www.rfc-editor.org/rfc/rfc7950>.
[RFC8174]
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC8340]
Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, , <https://www.rfc-editor.org/rfc/rfc8340>.
[RFC8342]
Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., and R. Wilton, "Network Management Datastore Architecture (NMDA)", RFC 8342, DOI 10.17487/RFC8342, , <https://www.rfc-editor.org/rfc/rfc8342>.

14.2. Informative References

[I-D.ietf-teas-rfc8776-update]
Busi, I., Guo, A., Liu, X., Saad, T., and I. Bryskin, "Common YANG Data Types for Traffic Engineering", Work in Progress, Internet-Draft, draft-ietf-teas-rfc8776-update-24, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-rfc8776-update-24>.
[RFC7951]
Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, , <https://www.rfc-editor.org/rfc/rfc7951>.
[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, , <https://www.rfc-editor.org/rfc/rfc8345>.
[RFC8795]
Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and O. Gonzalez de Dios, "YANG Data Model for Traffic Engineering (TE) Topologies", RFC 8795, DOI 10.17487/RFC8795, , <https://www.rfc-editor.org/rfc/rfc8795>.

Appendix A. Multi-domain fgOTN Hitless Resizing Process

The process of multi-domain fgOTN hitless resizing include five steps. The source controller alone report the hitless bandwidth adjustment status to the MDSC coordinator. To be noted that, the resizing process is divided into two directions, and the resizing is considered successful when both directions have been adjusted.

Step 1: The MDSC coordinator sends an resizing command to the source node (Node1) via Controller 1.

Step 2: Controller 1 will report a bandwidth adjustment starting status notification, e.g. ietf-te-types:lsp-bandwidth-modifying, to the MDSC.

Step 3: Node 1 to node 6 will modify their configuration in the forward direction through data plane node by node. The detail of this process can reference to Annex O.2 of [ITU-T_G.709].

Step 4: At the same time, the reverse direction bandwidth resizing will be triggered auotmatically by the data plane in node 6. Controller 3 needs to report an bandwidth adjustment starting status notification, ietf-te-types:lsp-bandwidth-modifying, to the MDSC.

Step 5: After the reverse direction (Node 6 to Node 1) resizing is completed, Controller 1 will report an ending status notification, ietf-te-types:lsp-bandwidth-modified-ok, to the MDSC.

If the hitless resizing fails, the source controller (i.e., Controller 1) needs to report an bandwidth adjustment failure status notification, ietf-te-types:lsp-bandwidth-modify-failed, to the MDSC coordinator.

During the whole process, all domain controllers, including the intermediate domain Controller 2, need to report the notifications of topology and tunnel resource changes to the MDSC.

Appendix B. JSON Examples

This appendix contains an example of an instance data tree in JSON encoding [RFC7951].

The example instantiates the "ietf-fgotn-topology" model for the OTN topology depicted in Figure 11 below.

(1) (2) NE2 (2) (2) (1) (1) NE1 NE4 (3) (3) NE3 (1) (2)
Figure 11: Example of fgOTN topology

In this network example:

The topology examples, show how the topology changes in three different steps:

  1. No OTN or fgOTN tunnels are setup in the network;

  2. The following ODUk tunnels are setup as server layer tunnels to support fgOTN tunnels: - an ODU1 tunnel between NE1 and NE2;

    • two ODU0 server layer tunnels between NE2 and NE4;

    • one ODU1 server layer tunnel between NE1 and NE4 (through the NE1-NE3-NE4 path)

  3. The following fgOTN tunnels are setup in the network: - a 20M protected fgOTN tunnel between NE1 and NE4 with:

    • a workting path setup through the NE1-NE2 ODU1 tunnel and the NE2-NE4 ODU0 tunnel;

    • a protectin path setup through the NE1-NE3-NE4 ODU1 tunnel; - an 20M unprotected fgOTN tunnel throught the same NE2-NE4 ODU0 tunnel used by the other fgOTN tunnel.

=============== NOTE: '\' line wrapping per RFC 8792 ================

{
  "ietf-network:networks": {
    "network": [
      {
        "network-id": "example:otn-topology-example-1",
        "network-types": {
          "ietf-te-topology:te-topology": {
            "ietf-otn-topology:otn-topology": {}
          }
        },
        "ietf-te-topology:te-topology-identifier": {
          "client-id": 2,
          "provider-id": 1,
          "topology-id": "otn-topology-example-1"
        },
        "ietf-te-topology:te": {},
        "ietf-network-topology:link": [
          {
            "link-id": "example:link/NE1-2/NE2-1",
            "source": {
              "source-node": "NE1",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE2",
              "dest-tp": "1"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE2 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE2-1/NE1-2",
            "source": {
              "source-node": "NE2",
              "source-tp": "1"
            },
            "destination": {
              "dest-node": "NE1",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE2 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE1-3/NE3-1",
            "source": {
              "source-node": "NE1",
              "source-tp": "3"
            },
            "destination": {
              "dest-node": "NE3",
              "dest-tp": "1"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE3 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE3-1/NE1-3",
            "source": {
              "source-node": "NE3",
              "source-tp": "1"
            },
            "destination": {
              "dest-node": "NE1",
              "dest-tp": "3"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE3 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE4-2/NE2-2",
            "source": {
              "source-node": "NE4",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE2",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE2 and Node NE4 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE2-2/NE4-2",
            "source": {
              "source-node": "NE2",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE4",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE2 and Node NE4 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE4-3/NE3-2",
            "source": {
              "source-node": "NE4",
              "source-tp": "3"
            },
            "destination": {
              "dest-node": "NE3",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "oper-status": "up",
              "te-link-attributes": {
                "admin-status": "up",
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE3 and Node NE4 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE3-2/NE4-3",
            "source": {
              "source-node": "NE3",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE4",
              "dest-tp": "3"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "ff"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 1
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 4
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 8
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE3 and Node NE4 (\
                                                  forward direction)"
              }
            }
          }
        ],
        "node": [
          {
            "node-id": "example:NE1",
            "ietf-te-topology:te-node-id": "192.0.0.1",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE1"
              }
            },
            "ietf-network-topology:termination-point": [
            {
                "tp-id": "example:NE1-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "ietf-otn-topology:client-svc": {},
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE1"
                }
            },
            {
                "tp-id": "example:NE1-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE1"
                }
              },
              {
                "tp-id": "example:NE1-3",
                "ietf-te-topology:te-tp-id": 3,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 3 of Node NE1"
                }
              }
            ]
          },
          {
            "node-id": "example:NE2",
            "ietf-te-topology:te-node-id": "192.0.0.2",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE2"
              }
            },
            "ietf-network-topology:termination-point": [
              {
                "tp-id": "example:NE2-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE2"
                }
              },
              {
                "tp-id": "example:NE2-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE2"
                }
              }
            ]
          },
          {
            "node-id": "example:NE3",
            "ietf-te-topology:te-node-id": "192.0.0.3",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE3"
              }
            },
            "ietf-network-topology:termination-point": [
              {
                "tp-id": "example:NE3-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE3"
                }
              },
              {
                "tp-id": "example:NE3-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE3"
                }
              }
            ]
          },
          {
            "node-id": "example:NE4",
            "ietf-te-topology:te-node-id": "192.0.0.4",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE4"
              }
            },
            "ietf-network-topology:termination-point": [
            {
                "tp-id": "example:NE4-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "ietf-otn-topology:client-svc": {},
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE4"
                }
            },
            {
                "tp-id": "example:NE4-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE4"
                }
              },
              {
                "tp-id": "example:NE4-3",
                "ietf-te-topology:te-tp-id": 3,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 3 of Node NE4"
                }
              }
            ]
          }
        ]
      },
      {
        "network-id": "example:otn-topology-example-2",
        "network-types": {
          "ietf-te-topology:te-topology": {
            "ietf-otn-topology:otn-topology": {}
          }
        },
        "ietf-te-topology:te-topology-identifier": {
          "client-id": 2,
          "provider-id": 1,
          "topology-id": "otn-topology-example-2"
        },
        "ietf-te-topology:te": {},
        "ietf-network-topology:link": [
          {
            "link-id": "example:link/NE1-2/NE2-1",
            "source": {
              "source-node": "NE1",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE2",
              "dest-tp": "1"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE2 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE2-1/NE1-2",
            "source": {
              "source-node": "NE2",
              "source-tp": "1"
            },
            "destination": {
              "dest-node": "NE1",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE2 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE1-3/NE3-1",
            "source": {
              "source-node": "NE1",
              "source-tp": "3"
            },
            "destination": {
              "dest-node": "NE3",
              "dest-tp": "1"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE3 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE3-1/NE1-3",
            "source": {
              "source-node": "NE3",
              "source-tp": "1"
            },
            "destination": {
              "dest-node": "NE1",
              "dest-tp": "3"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE3 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE4-2/NE2-2",
            "source": {
              "source-node": "NE4",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE2",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "1",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-119"
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-119"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE2 and Node NE4 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE2-2/NE4-2",
            "source": {
              "source-node": "NE2",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE4",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "1",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-119"
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-119"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE2 and Node NE4 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE4-3/NE3-2",
            "source": {
              "source-node": "NE4",
              "source-tp": "3"
            },
            "destination": {
              "dest-node": "NE3",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "oper-status": "up",
              "te-link-attributes": {
                "admin-status": "up",
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE3 and Node NE4 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE3-2/NE4-3",
            "source": {
              "source-node": "NE3",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE4",
              "dest-tp": "3"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE3 and Node NE4 (\
                                                  forward direction)"
              }
            }
          }
        ],
        "node": [
          {
            "node-id": "example:NE1",
            "ietf-te-topology:te-node-id": "192.0.0.1",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE1"
              }
            },
            "ietf-network-topology:termination-point": [
            {
                "tp-id": "example:NE1-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "ietf-otn-topology:client-svc": {},
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE1"
                }
            },
            {
                "tp-id": "example:NE1-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE1"
                }
              },
              {
                "tp-id": "example:NE1-3",
                "ietf-te-topology:te-tp-id": 3,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 3 of Node NE1"
                }
              }
            ]
          },
          {
            "node-id": "example:NE2",
            "ietf-te-topology:te-node-id": "192.0.0.2",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE2"
              }
            },
            "ietf-network-topology:termination-point": [
              {
                "tp-id": "example:NE2-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE2"
                }
              },
              {
                "tp-id": "example:NE2-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE2"
                }
              }
            ]
          },
          {
            "node-id": "example:NE3",
            "ietf-te-topology:te-node-id": "192.0.0.3",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE3"
              }
            },
            "ietf-network-topology:termination-point": [
              {
                "tp-id": "example:NE3-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE3"
                }
              },
              {
                "tp-id": "example:NE3-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE3"
                }
              }
            ]
          },
          {
            "node-id": "example:NE4",
            "ietf-te-topology:te-node-id": "192.0.0.4",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE4"
              }
            },
            "ietf-network-topology:termination-point": [
            {
                "tp-id": "example:NE4-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "ietf-otn-topology:client-svc": {},
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE4"
                }
            },
            {
                "tp-id": "example:NE4-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE4"
                }
              },
              {
                "tp-id": "example:NE4-3",
                "ietf-te-topology:te-tp-id": 3,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 3 of Node NE4"
                }
              }
            ]
          }
        ]
      },
      {
        "network-id": "example:otn-topology-example-3",
        "network-types": {
          "ietf-te-topology:te-topology": {
            "ietf-otn-topology:otn-topology": {}
          }
        },
        "ietf-te-topology:te-topology-identifier": {
          "client-id": 2,
          "provider-id": 1,
          "topology-id": "otn-topology-example-3"
        },
        "ietf-te-topology:te": {},
        "ietf-network-topology:link": [
          {
            "link-id": "example:link/NE1-2/NE2-1",
            "source": {
              "source-node": "NE1",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE2",
              "dest-tp": "1"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "1-2",
                          "fgts-unreserved": "3-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 950
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE2 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE2-1/NE1-2",
            "source": {
              "source-node": "NE2",
              "source-tp": "1"
            },
            "destination": {
              "dest-node": "NE1",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "1-2",
                          "fgts-unreserved": "3-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 950
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE2 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE1-3/NE3-1",
            "source": {
              "source-node": "NE1",
              "source-tp": "3"
            },
            "destination": {
              "dest-node": "NE3",
              "dest-tp": "1"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "4-5",
                          "fgts-unreserved": "1-3,6-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE3 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE3-1/NE1-3",
            "source": {
              "source-node": "NE3",
              "source-tp": "1"
            },
            "destination": {
              "dest-node": "NE1",
              "dest-tp": "3"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE1 and Node NE3 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE4-2/NE2-2",
            "source": {
              "source-node": "NE4",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE2",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "1",
                          "fgts-reserved": "2-4,20",
                          "fgts-unreserved": "1,5-19,21-119"
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-119"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 948
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE2 and Node NE4 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE2-2/NE4-2",
            "source": {
              "source-node": "NE2",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE4",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "1",
                          "fgts-reserved": "2-4,20",
                          "fgts-unreserved": "1,5-19,21-119"
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "odu-ts-number": "2",
                          "fgts-reserved": "",
                          "fgts-unreserved": "1-119"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 948
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE2 and Node NE4 (\
                                                  forward direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE4-3/NE3-2",
            "source": {
              "source-node": "NE4",
              "source-tp": "3"
            },
            "destination": {
              "dest-node": "NE3",
              "dest-tp": "2"
            },
            "ietf-te-topology:te": {
              "oper-status": "up",
              "te-link-attributes": {
                "admin-status": "up",
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc",
                      "ietf-fgotn-topology:fgts-range": [
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "odu-ts-number": "1-2",
                          "fgts-reserved": "4-5",
                          "fgts-unreserved": "1-3,6-238"
                        }
                      ]
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        },
                        {
                          "odu-type": "ietf-fgotn-types:fgODUflex",
                          "number": 952
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          },
                          {
                            "odu-type": "ietf-fgotn-types:fgODUflex",
                            "number": 952
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE3 and Node NE4 (\
                                                  reverse direction)"
              }
            }
          },
          {
            "link-id": "example:link/NE3-2/NE4-3",
            "source": {
              "source-node": "NE3",
              "source-tp": "2"
            },
            "destination": {
              "dest-node": "NE4",
              "dest-tp": "3"
            },
            "ietf-te-topology:te": {
              "te-link-attributes": {
                "interface-switching-capability": [
                  {
                    "encoding": "ietf-te-types:lsp-encoding-oduk",
                    "switching-capability": "ietf-te-types:switching\
                                                                -otn"
                  }
                ],
                "label-restrictions": {
                  "label-restriction": [
                    {
                      "index": 1,
                      "restriction": "inclusive",
                      "ietf-otn-topology:otn-label-range": {
                        "range-type": "trib-slot"
                      },
                      "label-start": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 1
                          }
                        }
                      },
                      "label-end": {
                        "te-label": {
                          "ietf-otn-topology:otn-label": {
                            "ts": 8
                          }
                        }
                      },
                      "label-step": {
                        "generic": 1
                      },
                      "range-bitmap": "fc"
                    }
                  ]
                },
                "max-link-bandwidth": {
                  "te-bandwidth": {
                    "ietf-otn-topology:otn-bandwidth": {
                      "odulist": [
                        {
                          "odu-type": "ietf-layer1-types:ODU2",
                          "number": 1
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU1",
                          "number": 4
                        },
                        {
                          "odu-type": "ietf-layer1-types:ODU0",
                          "number": 8
                        }
                      ]
                    }
                  }
                },
                "unreserved-bandwidth": [
                  {
                    "priority": 7,
                    "te-bandwidth": {
                      "ietf-otn-topology:otn-bandwidth": {
                        "odulist": [
                          {
                            "odu-type": "ietf-layer1-types:ODU2",
                            "number": 0
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU1",
                            "number": 3
                          },
                          {
                            "odu-type": "ietf-layer1-types:ODU0",
                            "number": 6
                          }
                        ]
                      }
                    }
                  }
                ],
                "name": "Link between Node NE3 and Node NE4 (\
                                                  forward direction)"
              }
            }
          }
        ],
        "node": [
          {
            "node-id": "example:NE1",
            "ietf-te-topology:te-node-id": "192.0.0.1",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE1"
              }
            },
            "ietf-network-topology:termination-point": [
            {
                "tp-id": "example:NE1-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "ietf-otn-topology:client-svc": {},
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE1"
                }
            },
            {
                "tp-id": "example:NE1-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE1"
                }
              },
              {
                "tp-id": "example:NE1-3",
                "ietf-te-topology:te-tp-id": 3,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 3 of Node NE1"
                }
              }
            ]
          },
          {
            "node-id": "example:NE2",
            "ietf-te-topology:te-node-id": "192.0.0.2",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE2"
              }
            },
            "ietf-network-topology:termination-point": [
              {
                "tp-id": "example:NE2-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE2"
                }
              },
              {
                "tp-id": "example:NE2-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE2"
                }
              }
            ]
          },
          {
            "node-id": "example:NE3",
            "ietf-te-topology:te-node-id": "192.0.0.3",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE3"
              }
            },
            "ietf-network-topology:termination-point": [
              {
                "tp-id": "example:NE3-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE3"
                }
              },
              {
                "tp-id": "example:NE3-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE3"
                }
              }
            ]
          },
          {
            "node-id": "example:NE4",
            "ietf-te-topology:te-node-id": "192.0.0.4",
            "ietf-te-topology:te": {
              "te-node-attributes": {
                "name": "Node NE4"
              }
            },
            "ietf-network-topology:termination-point": [
            {
                "tp-id": "example:NE4-1",
                "ietf-te-topology:te-tp-id": 1,
                "ietf-te-topology:te": {
                  "ietf-otn-topology:client-svc": {},
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 1 of Node NE4"
                }
            },
            {
                "tp-id": "example:NE4-2",
                "ietf-te-topology:te-tp-id": 2,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 2 of Node NE4"
                }
              },
              {
                "tp-id": "example:NE4-3",
                "ietf-te-topology:te-tp-id": 3,
                "ietf-te-topology:te": {
                  "interface-switching-capability": [
                    {
                      "encoding": "ietf-te-types:lsp-encoding-oduk",
                      "switching-capability": "ietf-te-types:\
                                                       switching-otn"
                    }
                  ],
                  "name": "Interface 3 of Node NE4"
                }
              }
            ]
          }
        ]
      }
    ]
  }
}

Acknowledgments

Contributors

Zelin Wang
China Unicom
Beijing
China
Aihua Guo
Huawei Technologiesicom
Chen Li
Fiberhome Telecommunication Technologies Co.,LTD

Authors' Addresses

Yanxia Tan
China Unicom
Beijing
China
Yanlei Zheng
China Unicom
Beijing
China
Italo Busi
Huawei Technologies
Chaode Yu
Huawei Technologies
China
Xing Zhao
CAICT
China