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YANG Data Models for fine grain Optical Transport Network
draft-ietf-ccamp-fgotn-yang-01

Document Type Active Internet-Draft (ccamp WG)
Authors Yanxia Tan , Zheng Yanlei , Italo Busi , Chaode Yu , XingZhao
Last updated 2026-07-29
Replaces draft-tan-ccamp-fgotn-yang
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draft-ietf-ccamp-fgotn-yang-01
CCAMP Working Group                                               Y. Tan
Internet-Draft                                                  Y. Zheng
Intended status: Standards Track                            China Unicom
Expires: 30 January 2027                                         I. Busi
                                                                   C. Yu
                                                     Huawei Technologies
                                                                 X. Zhao
                                                                   CAICT
                                                            29 July 2026

       YANG Data Models for fine grain Optical Transport Network
                     draft-ietf-ccamp-fgotn-yang-01

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/.

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   Internet-Drafts are draft documents valid for a maximum of six months
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   Copyright (c) 2026 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
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   Please review these documents carefully, as they describe your rights
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   provided without warranty as described in the Revised BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Terminology and Notations . . . . . . . . . . . . . . . .   3
     1.2.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   4
     1.3.  Requirements Language . . . . . . . . . . . . . . . . . .   4
     1.4.  Prefixes in Model Names . . . . . . . . . . . . . . . . .   4
   2.  Fine grain Optical Transport Network Scenarios Overview . . .   5
     2.1.  Retrieve Server Tunnels Scenario of fgOTN . . . . . . . .   6
     2.2.  Multi-layer Path Splicing Scenario of fgOTN . . . . . . .   6
     2.3.  Hitless Bandwidth Adjustment Scenario of fgOTN  . . . . .   7
   3.  YANG Data Model for fine grain Optical Transport Network
           Overview  . . . . . . . . . . . . . . . . . . . . . . . .   9
   4.  YANG Data Model for fgOTN Topology  . . . . . . . . . . . . .  10
     4.1.  Fine Grain OTN Topology Data Model Overview . . . . . . .  10
     4.2.  Bandwidth Augmentation  . . . . . . . . . . . . . . . . .  11
     4.3.  Label Augmentation  . . . . . . . . . . . . . . . . . . .  12
   5.  YANG Data Model for fgOTN Tunnel  . . . . . . . . . . . . . .  12
     5.1.  Fine Grain OTN Tunnel Data Model Overview . . . . . . . .  12
     5.2.  Bandwidth Augmentation  . . . . . . . . . . . . . . . . .  13
     5.3.  Label Augmentation  . . . . . . . . . . . . . . . . . . .  13
   6.  YANG Data Model for fgOTN types . . . . . . . . . . . . . . .  14
   7.  YANG Tree for fgOTN topology  . . . . . . . . . . . . . . . .  15
   8.  YANG Data Model for fgOTN topology  . . . . . . . . . . . . .  15
   9.  YANG Tree for fgOTN tunnel  . . . . . . . . . . . . . . . . .  19
   10. YANG Data Model for fgOTN tunnel  . . . . . . . . . . . . . .  19
   11. Manageability Considerations  . . . . . . . . . . . . . . . .  23

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   12. Security Considerations . . . . . . . . . . . . . . . . . . .  23
   13. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  23
   14. References  . . . . . . . . . . . . . . . . . . . . . . . . .  23
     14.1.  Normative References . . . . . . . . . . . . . . . . . .  23
     14.2.  Informative References . . . . . . . . . . . . . . . . .  25
   Appendix A.  Multi-domain fgOTN Hitless Resizing Process  . . . .  25
   Appendix B.  JSON Examples  . . . . . . . . . . . . . . . . . . .  26
   Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . .  94
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  94
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  94

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.

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   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.

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            +=============+=====================+============+
            | 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   |
            +-------------+---------------------+------------+

             Table 1: Prefixes and corresponding YANG modules

   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.

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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-

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   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.

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   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.

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                                 +----------+
                  +--------------+   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:

   *  A single network topology instance is used to report both OTN and
      fgOTN topology information: fgOTN technology-specific attributes
      are therefore defined in the fgOTN topology model as augmentations
      of the OTN topology model, but without defining a new network type
      for fgOTN.

   *  The OTN tunnel model can be used to setup either an OTN or an
      fgOTN tunnel: fgOTN technology-specific attributes are therefore
      defined in the fgOTN tunnel model as augmentations of the OTN
      tunnel model, which are applicable only when the OTN tunnel is an
      fgOTN tunnel.

   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

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   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.

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       +--------------+      +-----------------------+
       | 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.

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     "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.

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                   +------------------+
                   |      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.

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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.

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     // 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 {

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       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

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        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

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         "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

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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

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   <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).

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        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"

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           + "/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;

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         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, 16 June 2026,
              <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

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              Topology", Work in Progress, Internet-Draft, draft-ietf-
              ccamp-otn-topo-yang-21, 16 June 2026,
              <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, 27
              May 2026, <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, 26
              March 2026, <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 , March 2024,
              <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 ,
              May 2025, <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, March 1997,
              <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, June 2011,
              <https://www.rfc-editor.org/rfc/rfc6241>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/rfc/rfc7950>.

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   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <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, March 2018,
              <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, March 2018,
              <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, 12 June 2026, <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, August 2016,
              <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, March
              2018, <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, August 2020,
              <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.

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   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

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   In this network example:

   *  nodes NE1, NE2, and NE4 support fgOTN switching, while node NE3
      does not support fgOTN;

   *  all the links are OTU2 links

   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": {},

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           "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"
                       }
                     ]

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                   },
                   "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
                             }
                           ]

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                         }
                       }
                     }
                   ],
                   "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
                             }

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                           }
                         },
                         "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
                             },
                             {

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                               "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

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                             }
                           }
                         },
                         "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": [
                             {

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                               "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,

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                         "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,

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                       "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,

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                         "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
                           }
                         ]
                       }
                     }

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                   },
                   "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",

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                       "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

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                           },
                           {
                             "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": {

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                 "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": [
                           {

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                             "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)"

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                 }
               }
             },
             {
               "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"

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                       }
                     ]
                   },
                   "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)"

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                 }
               }
             }
           ],
           "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": [

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                       {
                         "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"
                   }
                 }

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               ]
             },
             {
               "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"
                 }

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               },
               "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"
                   }
                 }
               ]
             }
           ]

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         },
         {
           "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
                             }
                           }

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                         },
                         "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": [

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                     {
                       "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"

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                     }
                   ],
                   "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
                           },
                           {

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                             "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)"
                 }
               }
             },
             {

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               "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",

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                             "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

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                             },
                             {
                               "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
                             }
                           }

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                         },
                         "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

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                             },
                             {
                               "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
                             }
                           }

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                         },
                         "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

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                           }
                         ]
                       }
                     }
                   },
                   "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": {

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                 "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"
                           }
                         ]

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                       }
                     ]
                   },
                   "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

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                             }
                           ]
                         }
                       }
                     }
                   ],
                   "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": {

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                           "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,

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                       "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"
                     }
                   ],

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                   "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
                           }
                         ]
                       }
                     }

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                   },
                   "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",

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                         "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",

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                   "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"
                       }
                     ],

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                     "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": [

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                       {
                         "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": {

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                 "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"
                           }
                         ]
                       }
                     ]

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                   },
                   "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
                             }
                           ]

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                         }
                       }
                     }
                   ],
                   "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
                             }

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                           }
                         },
                         "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": [
                             {

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                               "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,

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                         "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

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                           },
                           {
                             "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": {

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                 "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

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                           },
                           {
                             "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": {

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                 "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",

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                             "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

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                             },
                             {
                               "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
                             }
                           }

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                         },
                         "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

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                           }
                         ]
                       }
                     }
                   },
                   "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": {

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                 "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": {

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                     "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
                             }
                           ]
                         }
                       }

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                     }
                   ],
                   "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
                             }
                           }
                         },

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                         "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
                             }
                           ]
                         }
                       }

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                     }
                   ],
                   "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"
                   }
                 },
                 {

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                   "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"
                       }

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                     ],
                     "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",

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               "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"
                   }

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                 }
               ]
             }
           ]
         }
       ]
     }
   }

Acknowledgments

Contributors

   Zelin Wang
   China Unicom
   Beijing
   China
   Email: wangzl172@chinaunicom.cn

   Aihua Guo
   Huawei Technologiesicom
   Email: aihuaguo.ietf@gmail.com

   Chen Li
   Fiberhome Telecommunication Technologies Co.,LTD
   Email: lich@fiberhome.com

Authors' Addresses

   Yanxia Tan
   China Unicom
   Beijing
   China
   Email: tanyx11@chinaunicom.cn

   Yanlei Zheng
   China Unicom
   Beijing
   China
   Email: zhengyanlei@chinaunicom.cn

   Italo Busi
   Huawei Technologies

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   Email: italo.busi@huawei.com

   Chaode Yu
   Huawei Technologies
   China
   Email: yuchaode@huawei.com

   Xing Zhao
   CAICT
   China
   Email: zhaoxing@caict.ac.cn

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