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Versions: 00 01 02                                                      
TEAS Working Group                                               I. Busi
Internet-Draft                                                    Huawei
Intended status: Informational                                    X. Liu
Expires: 13 January 2022                                  Volta Networks
                                                              I. Bryskin
                                                              Individual
                                                               V. Beeram
                                                                 T. Saad
                                                        Juniper Networks
                                                     O. Gonzalez de Dios
                                                              Telefonica
                                                            12 July 2021


       Profiles for Traffic Engineering (TE) Topology Data Model
                draft-busi-teas-te-topology-profiles-02

Abstract

   This document describes how profiles of the Traffic Engineering (TE)
   Topology Model, defined in RFC8795, can be used to address
   applications beyond "Traffic Engineering".

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on 13 January 2022.

Copyright Notice

   Copyright (c) 2021 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents (https://trustee.ietf.org/
   license-info) in effect on the date of publication of this document.



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   Please review these documents carefully, as they describe your rights
   and restrictions with respect to this document.  Code Components
   extracted from this document must include Simplified BSD License text
   as described in Section 4.e of the Trust Legal Provisions and are
   provided without warranty as described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Examples of non-TE scenarios  . . . . . . . . . . . . . . . .   3
     2.1.  UNI Topology Discovery  . . . . . . . . . . . . . . . . .   3
     2.2.  Administrative and Operational status management  . . . .   5
     2.3.  Geolocation . . . . . . . . . . . . . . . . . . . . . . .   6
     2.4.  Overlay and Underlay non-TE Topologies  . . . . . . . . .   7
     2.5.  Nodes with switching limitations  . . . . . . . . . . . .   8
   3.  Technology-specific augmentations . . . . . . . . . . . . . .   9
     3.1.  Multi-inheritance . . . . . . . . . . . . . . . . . . . .  11
     3.2.  Example (Link augmentation) . . . . . . . . . . . . . . .  12
   4.  Implemented profiles  . . . . . . . . . . . . . . . . . . . .  13
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  14
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  14
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Introduction

   There are many network scenarios being discussed in various IETF
   Working Groups (WGs) that are not classified as "Traffic Engineering"
   but can be addressed by a sub-set (profile) of the Traffic
   Engineering (TE) Topology YANG data model, defined in [RFC8795].

   Traffic Engineering (TE) is defined in [I-D.ietf-teas-rfc3272bis] as
   aspects of Internet network engineering that deal with the issues of
   performance evaluation and performance optimization of operational IP
   networks.  TE encompasses the application of technology and
   scientific principles to the measurement, characterization, modeling,
   and control of Internet traffic.

   The TE Topology Model is augmenting the Network Topology Model
   defined in [RFC8345] with generic and technology-agnostic features
   that some are strictly applicable to TE networks, while others
   applicable to both TE and non-TE networks.






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   Examples of such features that are applicable to both TE and non-TE
   networks are: inter-domain link discovery (plug-id), geo-
   localization, and admin/operational status.

   It is also worth noting that the TE Topology Model is quite an
   extensive and comprehensive model in which most features are
   optional.  Therefore, even though the full model appears to be
   complex, at the first glance, a sub-set of the model (profile) can be
   used to address specific scenarios, e.g. suitable also to non-TE use
   cases.

   The implementation of such TE Topology profiles can simplify and
   expedite adoption of the full TE topology YANG data model, and allow
   for its reuse even for non-TE use case.  The key question being
   whether all or some of the attributes defined in the TE Topology
   Model are needed to address a given network scenario.

   Section 2 provides examples where profiles of the TE Topology Model
   can be used to address some generic use cases applicable to both TE
   and non-TE technologies.

2.  Examples of non-TE scenarios

2.1.  UNI Topology Discovery

   UNI Topology Discovery is independent from whether the network is TE
   or non-TE.

   The TE Topology Model supports inter-domain link discovery (including
   but not being limited to UNI link discovery) using the plug-id
   attribute.  This solution is quite generic and does not require the
   network to be a TE network.

   The following profile of the TE Topology model can be used for the
   UNI Topology Discovery:

     module: ietf-te-topology
       augment /nw:networks/nw:network/nw:network-types:
         +--rw te-topology!
       augment /nw:networks/nw:network/nw:node/nt:termination-point:
         +--rw te-tp-id?   te-types:te-tp-id
         +--rw te!
            +--rw admin-status?
            |       te-types:te-admin-status
            +--rw inter-domain-plug-id?          binary
            +--ro oper-status?                   te-types:te-oper-status

                          Figure 1: UNI Topology



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   The profile data model shown in Figure 1 can be used to discover TE
   and non TE UNIs as well as to discover UNIs for TE or non TE
   networks.

   Such a UNI TE Topology profile model can also be used with
   technology-specific UNI augmentations, as described in section 3.

   For example, in [I-D.ietf-ccamp-eth-client-te-topo-yang], the eth-svc
   container is defined to represent the capabilities of the Termination
   Point (TP) to be configured as an Ethernet client UNI, together with
   the Ethernet classification and VLAN operations supported by that TP.

   The [I-D.ietf-ccamp-otn-topo-yang] provides another example, where:

   *  the client-svc container is defined to represent the capabilities
      of the TP to be configured as an transparent client UNI (e.g.,
      STM-N, Fiber Channel or transparent Ethernet);

   *  the OTN technology-specific Link Termination Point (LTP)
      augmentations are defined to represent the capabilities of the TP
      to be configured as an OTN UNI, together with the information
      about OTN label and bandwidth availability at the OTN UNI.

      For example, the UNI TE Topology profile can be used to model
      features defined in [I-D.ogondio-opsawg-uni-topology]:

   *  The inter-domain-plug-id attribute would provide the same
      information as the attachment-id attribute defined in
      [I-D.ogondio-opsawg-uni-topology];

   *  The admin-status and oper-status that exists in this TE topology
      profile can provide the same information as the admin-status and
      oper-status attributes defined in
      [I-D.ogondio-opsawg-uni-topology].

      Following the same approach in
      [I-D.ietf-ccamp-eth-client-te-topo-yang] and
      [I-D.ietf-ccamp-otn-topo-yang], the type and encapsulation-type
      attributes can be defined by technology- specific UNI
      augmentations to represent the capability of a TP to be configured
      as a L2VPN/L3VPN UNI Service Attachment Point (SAP).

      The advantages of using a TE Topology profile would be having
      common solutions for:

   *  discovering UNIs as well as inter-domain NNI links, which is
      applicable to any technology (TE or non TE) used at the UNI or
      within the network;



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   *  modelling non TE UNIs such as Ethernet, and TE UNIs such as OTN,
      as well as UNIs which can configured as TE or non-TE (e.g., being
      configured as either Ethernet or OTN UNI).

2.2.  Administrative and Operational status management

   The TE Topology Model supports the management of administrative and
   operational state, including also the possibility to associate some
   administrative names, for nodes, termination points and links.  This
   solution is generic and also does not require the network to be a TE
   network.

   The following profile of the TE Topology Model can be used for
   administrative and operational state management:

    module: ietf-te-topology
      augment /nw:networks/nw:network/nw:network-types:
        +--rw te-topology!
      augment /nw:networks/nw:network:
        +--rw te-topology-identifier
        |  +--rw provider-id?   te-global-id
        |  +--rw client-id?     te-global-id
        |  +--rw topology-id?   te-topology-id
        +--rw te!
           +--rw name?                     string
      augment /nw:networks/nw:network/nw:node:
        +--rw te-node-id?   te-types:te-node-id
        +--rw te!
           +--rw te-node-attributes
           |  +--rw admin-status?               te-types:te-admin-status
           |  +--rw name?                       string
           +--ro oper-status?                   te-types:te-oper-status
      augment /nw:networks/nw:network/nt:link:
        +--rw te!
           +--rw te-link-attributes
           |  +--rw name?                       string
           |  +--rw admin-status?               te-types:te-admin-status
           +--ro oper-status?                   te-types:te-oper-status
      augment /nw:networks/nw:network/nw:node/nt:termination-point:
        +--rw te-tp-id?   te-types:te-tp-id
        +--rw te!
           +--rw admin-status?                  te-types:te-admin-status
           +--rw name?                          string
           +--ro oper-status?                   te-types:te-oper-status

      Figure 2: Generic Topology with admin and operational state





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   The TE topology data model profile shown in Figure 2 is applicable to
   any technology (TE or non-TE) that requires management of the
   administrative and operational state and administrative names for
   nodes, termination points and links.

2.3.  Geolocation

   The TE Topology model supports the management of geolocation
   coordinates for nodes and termination points.  This solution is
   generic and does not necessarily require the network to be a TE
   network.

   The TE topology data model profile shown in Figure 3 can be used to
   model geolocation data for networks.

      module: ietf-te-topology
        augment /nw:networks/nw:network/nw:network-types:
          +--rw te-topology!
        augment /nw:networks/nw:network/nw:node/nt:termination-point:
          +--rw te-tp-id?   te-types:te-tp-id
          +--rw te!
             +--ro geolocation
                +--ro altitude?    int64
                +--ro latitude?    geographic-coordinate-degree
                +--ro longitude?   geographic-coordinate-degree
        augment /nw:networks/nw:network/nw:node:
          +--rw te-node-id?   te-types:te-node-id
          +--rw te!
             +--ro geolocation
                +--ro altitude?    int64
                +--ro latitude?    geographic-coordinate-degree
                +--ro longitude?   geographic-coordinate-degree
        augment /nw:networks/nw:network/nw:node/nt:termination-point:
          +--rw te-tp-id?   te-types:te-tp-id
          +--rw te!
             +--ro geolocation
                +--ro altitude?    int64
                +--ro latitude?    geographic-coordinate-degree
                +--ro longitude?   geographic-coordinate-degree

          Figure 3: Generic Topology with geolocation information

   This profile is applicable to any network technology (TE or non-TE)
   that requires management of the geolocation information for its nodes
   and termination points.






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2.4.  Overlay and Underlay non-TE Topologies

   The TE Topology model supports the management of overlay/underlay
   relationship for nodes and links, as described in section 5.8 of
   [RFC8795].  This solution is generic and does not require the network
   to be a TE network.

   The following TE topology data model profile can be used to manage
   overlay/underlay network data:

    module: ietf-te-topology
      augment /nw:netorks/nw:network/nw:network-types:
        +--rw te-topology!
      augment /nw:networks/nw:network/nw:node:
        +--rw te-node-id?   te-types:te-node-id
        +--rw te!
           +--rw te-node-attributes
              +--rw underlay-topology {te-topology-hierarchy}?
                 +--rw network-ref?   -> /nw:networks/network/network-id
      augment /nw:networks/nw:network/nt:link:
        +--rw te!
           +--rw te-link-attributes
              +--rw underlay {te-topology-hierarchy}?
                 +--rw enabled?                     boolean
                 +--rw primary-path
                    +--rw network-ref?
                    |       -> /nw:networks/network/network-id
                    +--rw path-element* [path-element-id]
                       +--rw path-element-id              uint32
                       +--rw (type)?
                          +--:(numbered-link-hop)
                          |  +--rw numbered-link-hop
                          |     +--rw link-tp-id    te-tp-id
                          |     +--rw hop-type?     te-hop-type
                          |     +--rw direction?    te-link-direction
                          +--:(unnumbered-link-hop)
                             +--rw unnumbered-link-hop
                                +--rw link-tp-id    te-tp-id
                                +--rw node-id       te-node-id
                                +--rw hop-type?     te-hop-type
                                +--rw direction?    te-link-direction

      Figure 4: Generic Topology with overlay/underlay information








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   This profile is applicable to any technology (TE or non-TE) when it
   is needed to manage the overlay/underlay information.  It is also
   allows a TE underlay network to support a non-TE overlay network and,
   vice versa, a non-TE underlay network to support a TE overlay
   network.

2.5.  Nodes with switching limitations

   A node can have some switching limitations where connectivity is not
   possible between all its TP pairs, for example when:

   *  the node represents a physical device with switching limitations;

   *  the node represents an abstraction of a network topology.

   This scenario is generic and applies to both TE and non-TE
   technologies.

   A connectivity TE Topology profile data model supports the management
   of the node connectivity matrix to represent feasible connections
   between termination points across the nodes.  This solution is
   generic and does not necessarily require a TE enabled network.

   The following profile of the TE Topology model can be used for nodes
   with connectivity constraints:

      module: ietf-te-topology
        augment /nw:networks/nw:network/nw:network-types:
          +--rw te-topology!
        augment /nw:networks/nw:network/nw:node:
          +--rw te-node-id?   te-types:te-node-id
          +--rw te!
             +--rw te-node-attributes
                +--rw connectivity-matrices
                   +--rw number-of-entries?     uint16
                   +--rw is-allowed?            boolean
                   +--rw connectivity-matrix* [id]
                      +--rw id                  uint32
                      +--rw from
                      |  +--rw tp-ref?               leafref
                      +--rw to
                      |  +--rw tp-ref?               leafref
                      +--rw is-allowed?              boolean

          Figure 5: Generic Topology with connectivity constraints






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   The TE topology data model profile shown in Figure 5 is applicable to
   any technology (TE or non-TE) networks that requires managing nodes
   with certain connectivity constraints.  When used with TE
   technologies, additional TE attributes, as defined in [RFC8795], can
   also be provided.

3.  Technology-specific augmentations

   There are two main options to define technology-specific Topology
   Models which can use the attributes defined in the TE Topology Model
   [RFC8795].

   Both options are applicable to any possible profile of the TE
   Topology Model, such as those defined in Section 2.

   The first option is to define a technology-specific TE Topology Model
   which augments the TE Topology Model, as shown in Figure 6:

                              +-------------------+
                              | Network Topology  |
                              +-------------------+
                                        ^
                                        |
                                        | Augments
                                        |
                            +-----------+-----------+
                            |      TE Topology      |
                            |       (profile)       |
                            +-----------------------+
                                        ^
                                        |
                                        | Augments
                                        |
                             +----------+----------+
                             | Technology-Specific |
                             |     TE Topology     |
                             +---------------------+

                 Figure 6: Augmenting the TE Topology Model

   This approach is more suitable for cases when the technology-specific
   TE topology model provides augmentations to the TE Topology
   constructs, such as bandwidth information (e.g., link bandwidth),
   tunnel termination points (TTPs) or connectivity matrices.  It also
   allows providing augmentations to the Network Topology constructs,
   such as nodes, links, and termination points (TPs).





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   This is the approach currently used in
   [I-D.ietf-ccamp-eth-client-te-topo-yang] and
   [I-D.ietf-ccamp-otn-topo-yang].

   It is worth noting that a profile of the technology-specific TE
   Topology model not using any TE topology attribute or constructs can
   be used to address any use case that do not require these attributes.
   In this case, only the te-topology presence container of the TE
   Topology Model needs to be implemented.

   The second option is to define a technology-specific Network Topology
   Model which augments the Network Topology Model and to rely on the
   multiple inheritance capability, which is implicit in the network-
   types definition of [RFC8345], to allow using also the generic
   attributes defined in the TE Topology model:

                       +-----------------------+
                       |    Network Topology   |
                       +-----------------------+
                           ^               ^
                           |               |
              Augments +---+               +--+ Augments
                       |                      |
             +---------+---+       +----------+----------+
             | TE Topology |       | Technology-specific |
             |  (profile)  |       |  Network Topology   |
             +-------------+       +---------------------+

        Figure 7: Augmenting the Network Topology Model with multi-
                                inheritance

   This approach is more suitable in cases where the technology-specific
   Network Topology Model provides augmentation only to the constructs
   defined in the Network Topology Model, such as nodes, links, and
   termination points (TPs).  Therefore, with this approach, only the
   generic attributes defined in the TE Topology Model could be used.

   It is also worth noting that in this case, technology-specific
   augmentations for the bandwidth information could not be defined.

   In principle, it would be also possible to define both a technology
   specific TE Topology Model which augments the TE Topology Model, and
   a technology-specific Network Topology Model which augments the
   Network Topology Model and to rely on the multiple inheritance
   capability, as shown in Figure 8:






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                       +-----------------------+
                       |    Network Topology   |
                       +-----------------------+
                           ^               ^
                           |               |
              Augments +---+               +--+ Augments
                       |                      |
             +---------+---+       +----------+----------+
             | TE Topology |       | Technology-specific |
             |  (profile)  |       |  Network Topology   |
             +-------------+       +---------------------+
                    ^                         ^
                    |                         |
                    | Augments                | References
                    |                         |
         +----------+----------+              |
         | Technology-Specific +--------------+
         |     TE Topology     |
         +---------------------+

        Figure 8: Augmenting both the Network and TE Topology Models

   This option does not provide any technical advantage with respect to
   the first option, shown in Figure 6, but could be useful to add
   augmentations to the TE Topology constructs and to re-use an already
   existing technology-specific Network Topology Model.

   It is worth noting that the technology-specific TE Topology model can
   reference constructs defined by the technology-specific Network
   Topology model but it could not augment constructs defined by the
   technology-specific Network Topology model.

3.1.  Multi-inheritance

   As described in section 4.1 of [RFC8345], the network types should be
   defined using presence containers to allow the representation of
   network subtypes.

   The hierachy of netwok subtypes can be single hierarchy, as shown in
   Figure 6.  In this case, each presence container contains at most one
   child presence container, as shows in the JSON code below:










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   {
     "ietf-network:ietf-network": {
       "ietf-te-topology:te-topology": {
         "example-te-topology": {}
       }
     }
   }

   The hierachy of netwok subtypes can also be multi-hierarchy, as shown
   in Figure 7 and Figure 8.  In this case, one presence container can
   contain more than one child presence containers, as show in the JSON
   codes below:

   {
     "ietf-network:ietf-network": {
       "ietf-te-topology:te-topology": {}
       "example-network-topology": {}
     }
   }

   {
     "ietf-network:ietf-network": {
       "ietf-te-topology:te-topology": {
         "example-te-topology": {}
       }
       "example-network-topology": {}
     }
   }

   Other examples of multi-hierarchy topologies are described in
   [I-D.ietf-teas-yang-sr-te-topo].

3.2.  Example (Link augmentation)

   This section provides an example on how technology-specific
   attributes can be added to the Link construct:















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         +--rw link* [link-id]
            +--rw link-id            link-id
            +--rw source
            |  +--rw source-node?   -> ../../../nw:node/node-id
            |  +--rw source-tp?     leafref
            +--rw destination
            |  +--rw dest-node?   -> ../../../nw:node/node-id
            |  +--rw dest-tp?     leafref
            +--rw supporting-link* [network-ref link-ref]
            |  +--rw network-ref
            |  |       -> ../../../nw:supporting-network/network-ref
            |  +--rw link-ref       leafref
            +--rw example-link-attributes
            |   <...>
            +--rw te!
               +--rw te-link-attributes
                  +--rw name?                             string
                  +--rw example-te-link-attributes
                  |   <...>
                  +--rw max-link-bandwidth
                     +--rw te-bandwidth
                        +--rw (technology)?
                           +--:(generic)
                           |  +--rw generic?   te-bandwidth
                           +--:(example)
                              +--rw example?   example-bandwidth

     Figure 9: Augmenting the Link with technology-specific attributes

   The technology-specific attributes within the example-link-attributes
   container can be defined either in the technology-specific TE
   Topology Model (Option 1) or in the technology-specific Network
   Topology Model (Option 2 or Option 3).  These attributes can only be
   non-TE and do not require the implementation of the te container.

   The technology-specific attributes within the example-te-link-
   attributes container as well as the example max-link-bandwidth can
   only be defined in the technology-specific TE Topology Model (Option
   1 or Option 3).  These attributes can be TE or non-TE and require the
   implementation of the te container.

4.  Implemented profiles

   When a server implements a profile of the TE topology model, it is
   not clear how the server can report to the client the subset of the
   model being implemented.





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   It is also worth noting that the supported profile may also depend on
   other attributes (for example the network type).

   In case the TE topology profile is reported by the server to the
   client, the server will report in the operational datastore only the
   leaves which have been implemented, as described in section 5.3 of
   [RFC8342].

   More investigation is required in case the TE topology profile is
   configured by the client.

5.  Security Considerations

   This document provides only information about how the TE Topology
   Model, as defined in [RFC8795], can be profiled to address some
   scenarios which are not considered as TE.

   As such, this document does not introduce any additional security
   considerations besides those already defined in [RFC8795].

6.  IANA Considerations

   This document requires no IANA actions.

7.  References

7.1.  Normative References

   [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/info/rfc8342>.

   [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/info/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/info/rfc8795>.

7.2.  Informative References






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   [I-D.ietf-ccamp-eth-client-te-topo-yang]
              Zheng, H., Guo, A., Busi, I., Xu, Y., Zhao, Y., and X.
              Liu, "A YANG Data Model for Ethernet TE Topology", Work in
              Progress, Internet-Draft, draft-ietf-ccamp-eth-client-te-
              topo-yang-00, 9 March 2021,
              <https://www.ietf.org/archive/id/draft-ietf-ccamp-eth-
              client-te-topo-yang-00.txt>.

   [I-D.ietf-ccamp-otn-topo-yang]
              Zheng, H., Busi, I., Liu, X., Belotti, S., and O. G. D.
              Dios, "A YANG Data Model for Optical Transport Network
              Topology", Work in Progress, Internet-Draft, draft-ietf-
              ccamp-otn-topo-yang-13, 12 July 2021,
              <https://www.ietf.org/archive/id/draft-ietf-ccamp-otn-
              topo-yang-13.txt>.

   [I-D.ietf-teas-rfc3272bis]
              Farrel, A., "Overview and Principles of Internet Traffic
              Engineering", Work in Progress, Internet-Draft, draft-
              ietf-teas-rfc3272bis-12, 15 May 2021,
              <https://www.ietf.org/archive/id/draft-ietf-teas-
              rfc3272bis-12.txt>.

   [I-D.ietf-teas-yang-sr-te-topo]
              Liu, X., Bryskin, I., Beeram, V. P., Saad, T., Shah, H.,
              and S. Litkowski, "YANG Data Model for SR and SR TE
              Topologies on MPLS Data Plane", Work in Progress,
              Internet-Draft, draft-ietf-teas-yang-sr-te-topo-10, 6 July
              2021, <https://www.ietf.org/archive/id/draft-ietf-teas-
              yang-sr-te-topo-10.txt>.

   [I-D.ogondio-opsawg-uni-topology]
              Dios, O. G. D., Barguil, S., Wu, Q., and M. Boucadair, "A
              YANG Model for User-Network Interface (UNI) Topologies",
              Work in Progress, Internet-Draft, draft-ogondio-opsawg-
              uni-topology-01, 2 April 2020,
              <https://www.ietf.org/archive/id/draft-ogondio-opsawg-uni-
              topology-01.txt>.

Contributors

   Aihua Guo
   Futurewei Inc.

   Email: aihuaguo.ietf@gmail.com






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Internet-Draft            TE Topology Profiles                 July 2021


   Haomian Zheng
   Huawei

   Email: zhenghaomian@huawei.com


   Sergio Belotti
   Nokia

   Email: sergio.belotti@nokia.com


Authors' Addresses

   Italo Busi
   Huawei

   Email: italo.busi@huawei.com


   Xufeng Liu
   Volta Networks

   Email: xufeng.liu.ietf@gmail.com


   Igor Bryskin
   Individual

   Email: i_bryskin@yahoo.com


   Vishnu Pavan Beeram
   Juniper Networks

   Email: vbeeram@juniper.net


   Tarek Saad
   Juniper Networks

   Email: tsaad@juniper.net


   Oscar Gonzalez de Dios
   Telefonica

   Email: oscar.gonzalezdedios@telefonica.com



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