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Versions: 00 01 02 draft-ietf-ccamp-mw-topo-yang

CCAMP Working Group                                           M. Ye, Ed.
Internet-Draft                                                    A. Guo
Intended status: Standards Track                     Huawei Technologies
Expires: January 1, 2019                                      J. Ahlberg
                                                             Ericsson AB
                                                                   X. Li
                                            NEC Laboratories Europe GmbH
                                                            D. Spreafico
                                                              Nokia - IT
                                                           June 30, 2018


                A YANG Data Model for Microwave Topology
                     draft-ye-ccamp-mw-topo-yang-01

Abstract

   This document defines a YANG data model to describe the topologies of
   microwave/millimeter.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC2119].

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 January 1, 2019.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.




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   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include 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.  Terminology and Definitions . . . . . . . . . . . . . . . . .   2
   2.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   3.  YANG Data Model (Tree Structure)  . . . . . . . . . . . . . .   3
     3.1.  The YANG Tree . . . . . . . . . . . . . . . . . . . . . .   3
     3.2.  Relationship with microwave interface YANG model  . . . .   3
   4.  YANG Module . . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .   7
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .   8
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .   8
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .   8
     7.2.  Informative References  . . . . . . . . . . . . . . . . .   9
   Appendix A.  Appendix A Examples of microwave topology  . . . . .  10
     A.1.  Appendix A.1 A topology with single microwave radio link   10
     A.2.  Appendix A.2 A topology with microwave radio links
           bundling  . . . . . . . . . . . . . . . . . . . . . . . .  12
   Appendix B.  Contributors . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Terminology and Definitions

   The following acronyms are used in this document:

   PNC Provisioning Network Controller

   MDSC Multi Domain Service Coordinator

2.  Introduction

   This document defines a YANG data model to describe the topologies of
   microwave/millimeter(hereafter microwave is used to simplify the
   text).  The microwave topology model augments the TE topology model
   defines in [I-D.ietf-teas-yang-te-topo].

   The microwave topology model is expected to be used between a
   Provisioning Network Controller(PNC) and a Multi Domain Service




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   Coordinator(MDSC)([I-D.ietf-teas-actn-framework]).  Possible use
   cases of microwave topology models include:

   1.  The microwave link frequency could be used to understand the
       current frequency usage, enabling a whole view of the network
       topology information, and as an input for network frequency
       planning.

   2.  The microwave radio link could change its bandwidth according to
       the environments under the adaptive modulation mode, e.g., the
       bandwidth will degrade when there's a heavy rain.  To get to know
       of current microwave link bandwidth is important for path
       computation and service provisioning across different
       technologies/networks.

   3.  Due to bandwidth changing feature, availability is normally used
       to describe the microwave radio link characteristic.  [RFC8330]
       defines a mechanism to report bandwidth-availability information
       through OSPF-TE.  It's also necessary to include the information
       in the YANG data model to optimize the path/route computation.

3.  YANG Data Model (Tree Structure)

3.1.  The YANG Tree


module: ietf-microwave-topology
  augment /nw:networks/nw:network/nw:network-types/tet:te-topology:
    +--rw mw-topology!
  augment /nw:networks/nw:network/nt:link/tet:te/tet:te-link-attributes:
        +--rw mw-link-frequency?             uint32
        +--rw mw-link-channel-separation?    uint32
        +--ro mw-link-nominal-bandwidth? rt-types:bandwidth-ieee-float32
        +--ro mw-link-current-bandwidth? rt-types:bandwidth-ieee-float32
        +--rw mw-unreserved-bandwidth    rt-types:bandwidth-ieee-float32
        +--rw mw-link-availability* [availability]
           +--rw mw-link-availability    rt-types:percentage
           +--ro mw-link-bandwidth       rt-types:bandwidth-ieee-float32
  augment /nw:networks/nw:network/nw:node/nt:termination-point /tet:te:
    +-- mp interface-root


3.2.  Relationship with microwave interface YANG model

   The microwave topology model is expected to be used between a PNC and
   a MDSC.  [I-D.ietf-ccamp-mw-yang] defines an interface YANG model for
   microwave radio link which is used between the PNC and the physical
   device for device configuration.  The PNC is able to convert the



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   information received from the topology model into the interface
   model.  For example, the link frequency in the topology model is
   mapped to the tx-frequency of the carrier termination in the
   interface model.

   If the purpose is to access more information of the microwave
   interface YANG model through the microwave topology model, a schema
   mount mechanism could be used, see the "interface-root" in the
   microwave topology model.  [I-D.ietf-netmod-schema-mount] defines a
   mechanism to add the schema trees defined by a set of YANG modules
   onto a mount point defined in the schema tree in some YANG module.
   The current defined schema mount mechanism allows mounting of
   complete data models only.  If complete mounting of the microwave
   interface YANG model is not neceesary, a deviation model could be
   created to remove unneeded schema in the microwave interface model,
   and be mounted to the topology model.

4.  YANG Module


   <CODE BEGINS> file "ietf-microwave-topology.yang"

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

     prefix "mwtopo";

     import ietf-network {
       prefix "nw";
     }

     import ietf-network-topology {
       prefix "nt";
     }

     import ietf-te-topology {
       prefix "tet";
     }

     import ietf-routing-types {
       prefix "rt-types";
     }

     import ietf-yang-schema-mount {
          prefix yangmnt;
          reference "draft-ietf-netmod-schema-mount: YANG Schema Mount";
        }



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    organization
     "Internet Engineering Task Force (IETF) CCAMP WG";
    contact
     "
     WG List: <mailto:ccamp@ietf.org>

     ID-draft authors:
      Min Ye (amy.yemin@huawei.com);
      Aihua Guo (aihuaguo@huawei.com);
      Jonas Ahlberg (jonas.ahlberg@ericsson.com);
      Xi Li (Xi.Li@neclab.eu);
      Daniela Spreafico (daniela.spreafico@nokia.com)
     ";

    description
     "This is a module for microwave topology.";

      revision 2018-06-30 {
       description
       "Updated version to add mount point to the interface model.";
       reference "";
     }

      revision 2018-03-05 {
       description
       "Initial version.";
       reference "";
     }


     /*
      * Groupings
      */
     grouping mw-link-attributes {
        description "Microwave link attributes";

            leaf mw-link-frequency {
              type uint32;
              units "kHz";
              description "Frequency of the link";
              }

            leaf mw-link-channel-separation {
              type uint32;
              units "kHz";
              description "The distance
               between adjacent channels in a radio frequency channel
               arrangement used in this link";



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              reference "ETSI EN 302 217-1";
              }

             leaf mw-link-nominal-bandwidth {
               type rt-types:bandwidth-ieee-float32;
                   units "Mbps";
                   config false;
                   description "The nominal bandwidth of the link";
             }

             leaf mw-link-current-bandwidth {
              type rt-types:bandwidth-ieee-float32;
              units "Mbps";
              config false;
              description "The current bandwidth of the link";
              }

             leaf mw-unreserved-bandwidth {
              type rt-types:bandwidth-ieee-float32;
              units "Mbps";
              description "the unreserved bandwidth of the link";
              }


             list mw-link-availability{
                   key "availability";
                   description "List of availability and corresponding
                                link bandwidth";

                   leaf availability {
                     type rt-types:percentage;
                     description "availability level of the link";
                   }

                   leaf mw-link-bandwidth {
                     type rt-types:bandwidth-ieee-float32;
                     units "Mbps";
                     config false;
                     description "The link bandwidth corresponding
                                  to the availability level";
                     }
        }

         container "interface-root" {
              description
                "Container for mount point.";
              yangmnt:mount-point "interface-root" {
                description



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                  "Root for microwave rado interface model.
                               It could contain an interface instance.";
              }
            }

           }

     /*
      * Data nodes
      */
      augment "/nw:networks/nw:network/nw:network-types/"
           + "tet:te-topology" {
       container mw-topology {
         presence "indicates a topology type of microwave.";
         description "microwave topology type";
       }
       description "augment network types to include microwave network";
     }

     augment "/nw:networks/nw:network/nt:link/tet:te/"
           + "tet:te-link-attributes" {
       when "../../../nw:network-types/tet:te-topology/"
          + "mwtopo:mw-topology" {
         description "This augment is only valid for microwave.";
       }
       description "Microwave link augmentation";

       uses mw-link-attributes;
     }

    }
   <CODE ENDS>


5.  Security Considerations

   The YANG module specified in this document defines a schema for data
   that is designed to be accessed via network management protocols such
   as NETCONF [RFC6241] or RESTCONF [RFC8040][RFC8040].  The lowest
   NETCONF layer is the secure transport layer, and the mandatory-to-
   implement secure transport is Secure Shell (SSH) [RFC6242].  The
   lowest RESTCONF layer is HTTPS, and the mandatory-to-implement secure
   transport is TLS [RFC5246].

   The NETCONF access control model [RFC8341] provides the means to
   restrict access for particular NETCONF or RESTCONF users to a
   preconfigured subset of all available NETCONF or RESTCONF protocol
   operations and content.



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   There are a number of data nodes defined in this YANG module that are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive or vulnerable
   in some network environments.  Write operations (e.g., edit-config)
   to these data nodes without proper protection can have a negative
   effect on network operations.  These are the subtrees and data nodes
   and their sensitivity/vulnerability:

   TBD.(list subtrees and data nodes and state why they are sensitive)

   Some of the readable data nodes in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control read access (e.g., via get, get-config, or
   notification) to these data nodes.  These are the subtrees and data
   nodes and their sensitivity/vulnerability:

   TBD.(list subtrees and data nodes and state why they are sensitive)

6.  IANA Considerations

   IANA has assigned a new URI from the "IETF XML Registry" [RFC3688].

             URI: urn:ietf:params:xml:ns:yang:ietf-microwave-topology
             Registrant Contact: The IESG
             XML: N/A; the requested URI is an XML namespace.

   IANA has recorded a YANG module name in the "YANG Module Names"
   registry [RFC6020] as follows:

          Name: ietf-microwave-topology
          Namespace: urn:ietf:params:xml:ns:yang:ietf-microwave-topology
          Prefix: mwtopo
          Reference: RFC xxxx

7.  References

7.1.  Normative References

   [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/info/rfc2119>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.





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   [RFC5246]  Dierks, T. and E. Rescorla, "The Transport Layer Security
              (TLS) Protocol Version 1.2", RFC 5246,
              DOI 10.17487/RFC5246, August 2008,
              <https://www.rfc-editor.org/info/rfc5246>.

   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [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/info/rfc6241>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

7.2.  Informative References

   [I-D.ietf-ccamp-mw-yang]
              Ahlberg, J., Ye, M., Li, X., Spreafico, D., and M.
              Vaupotic, "A YANG Data Model for Microwave Radio Link",
              draft-ietf-ccamp-mw-yang-06 (work in progress), June 2018.

   [I-D.ietf-netmod-schema-mount]
              Bjorklund, M. and L. Lhotka, "YANG Schema Mount", draft-
              ietf-netmod-schema-mount-10 (work in progress), April
              2018.

   [I-D.ietf-teas-actn-framework]
              Ceccarelli, D. and Y. Lee, "Framework for Abstraction and
              Control of Traffic Engineered Networks", draft-ietf-teas-
              actn-framework-15 (work in progress), May 2018.







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   [I-D.ietf-teas-yang-te-topo]
              Liu, X., Bryskin, I., Beeram, V., Saad, T., Shah, H., and
              O. Dios, "YANG Data Model for Traffic Engineering (TE)
              Topologies", draft-ietf-teas-yang-te-topo-18 (work in
              progress), June 2018.

   [RFC8330]  Long, H., Ye, M., Mirsky, G., D'Alessandro, A., and H.
              Shah, "OSPF Traffic Engineering (OSPF-TE) Link
              Availability Extension for Links with Variable Discrete
              Bandwidth", RFC 8330, DOI 10.17487/RFC8330, February 2018,
              <https://www.rfc-editor.org/info/rfc8330>.

Appendix A.  Appendix A Examples of microwave topology

A.1.  Appendix A.1 A topology with single microwave radio link

   Microwave is a transport technology which can be used to transport
   client services, such as ETH.  When an ETH service is transported by
   a single microwave radio link, the topology could be shown as the
   Figure 3.  Note that the figure just shows an example, there might be
   other possiblities to demonstrate the topology.

      Node 1                              Node 2
+---------------+                     +---------------+
|               |                     |               |
| +-----------+ |                     | +-----------+ |
| |    LTP11  | |                     | |   LTP21   | | --ETH topo
| +-------o---+ |  ETH-TE-Link-1      | +---o-------+ |
|         |---------------------------------|         |
|               |                     |               |
| +-----------+ |                     | +-----------+ |
| | TTP-1 __  | | microwave tunnel-11 | |  __ TTP-1 | |
| |       \/@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\/       | |
| |        *  | |                     | |  *        | | --Microwave topo
| |         * | | microwave link 12   | | *         | |
| |    LTP-1 *o ------------------------o* LTP-1    | |
| |           | |                     | |           | |
| +-----------+ |                     | +-----------+ |
|               |                     |               |
+---------------+                     +---------------+

        Figure 3: ETH transported on a single microwave radio link

   In the above ETH topology, the ETH-TE-link is encoded in JSON as
   below:






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     ...
     "ietf-network-topology:link": [
       {
         "link-id": "N1,LTP11,N2,LTP21",
         "source": {
           "source-node": "N1",
           "source-tp": "LTP11"
         }
         "destination": {
           "dest-node": "N2",
           "dest-tp": "LTP21"
         }
       }
     ]
     "ietf-te-topology:link/te/te-link-attributes/": [
       {
         "enabled": ture,
             "primary-path":{
              "path-element": {
                "path-element-id": "MW-11"
                    //no backup-path
                    //no protection-type
              }
             }
             "tunnel-termination-points": {
               "source": "N1/TTP-1",
                   "destination": "N2/TTP-1"
             }
             "tunnels" : {
              "sharing": "false",
              "tunnel":{
                "tunnel-name": "MW-11",
                    "sharing": "false"
              }
             }
           }
     ]

   Note that the example above just shows the particular ETH link, not
   the full ETH topology.

   In the microwave topology, the microwave link is encoded in JSON as
   below:








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     ...
     "ietf-network-topology:link": [
       {
         "link-id": "N1,LTP1,N2,LTP1",
         "source": {
           "source-node": "N1",
           "source-tp": "LTP1"
         }
         "destination": {
           "dest-node": "N2",
           "dest-tp": "LTP1"
         }
       }
     ]
     "ietf-te-topology:link/te/te-link-attributes/underlay": [
       {
            "mw-link-frequency":  10728000,
            "mw-link-channel-separation": "28000",
            "mw-link-actual-tx-cm":"qam-512",
            "mw-link-nominal-bandwidth": "1000",
            "mw-link-current-bandwidth": "1000",
            "mw-link-availability":{
             "mw-link-availability":"0.9999",
             "mw-link-bandwidth": "1000"
            }
           }
     ]

A.2.  Appendix A.2 A topology with microwave radio links bundling

   When a ETH service is transported over two microwave radio links, the
   topologies could be shown as in Figure 4.  Note that the figure just
   shows one example, there might be other possiblities to demonstrate
   the topology.

















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      Node 1                              Node 2
+---------------+                     +---------------+
|               |                     |               |
| +-----------+ |                     | +-----------+ |
| |    LTP11  | |                     | |   LTP21   | | --ETH topo
| +-------o---+ |  ETH-TE-Link-1      | +---o-------+ |
|         |---------------------------------|         |
|               |                     |               |
| +-----------+ |                     | +-----------+ |
| | TTP-1 __  | | microwave tunnel-11 | |  __ TTP-1 | |
| |       \/@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@\/       | |
| |        *  | |                     | |  *        | | --Microwave topo
| |         * | | mw bundled link 33  | | *         | |
| |    LTP-3 *o ------------------------o* LTP-3    | |
| |           | |                     | |           | |
| |    LTP-2  o |                     | o  LTP-2    | |
| |    LTP-1  o |                         | o  LTP-1    | |
| +-----------+ |                     | +-----------+ |
|               |                     |               |
+---------------+                     +---------------+

         Figure 4: ETH transported on single microwave radio links

   In the ETH topology, the ETH-TE-link is encoded in JSON as below:



























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     ...
     "ietf-network-topology:link": [
       {
         "link-id": "N1,LTP11,N2,LTP21",
         "source": {
           "source-node": "N1",
           "source-tp": "LTP11"
         }
         "destination": {
           "dest-node": "N2",
           "dest-tp": "LTP21"
         }
       }
     ]
     "ietf-te-topology:link/te/te-link-attributes/": [
       {
         "enabled": ture,
             "primary-path":{
              "path-element": {
                "path-element-id": "MW-33"
                    //no backup-path
                    //no protection-type
              }
             }
             "tunnel-termination-points": {
               "source": "N1/TTP-1",
                   "destination": "N2/TTP-1"
             }
             "tunnels" : {
              "sharing": "false",
              "tunnel":{
                "tunnel-name": "MW-11",
                    "sharing": "false"
              }
             }
           }
     ]

   Note that the example above just shows the specific ETH link, not the
   full ETH topology.

   In the microwave topology, the micorwave link is encoded in JSON as
   below:








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     ...
     "ietf-network-topology:link": [
       {
         "link-id": "N1,LTP1,N2,LTP1",
         "source": {
           "source-node": "N1",
           "source-tp": "LTP3"
         }
         "destination": {
           "dest-node": "N2",
           "dest-tp": "LTP3"
         }
       }
     ]
     "ietf-te-topology:link/te/te-link-config": [
       {
            "bundle-stack-level":{
              "component" {
                "component-links-1": {
              "sequence": "mw-11",
              "src-tp-ref": "N1-LTP1",
              "des-tp-ref" : "N2-LTP1"
                    }
                     "component-links-2": {
              "sequence": "mw-22",
              "src-tp-ref": "N1-LTP2"
              "des-tp-ref" : "N2-LTP2"
                    }
              }
            }
           }
     ]

   Note that the example above just shows the microwave component links,
   it doesn't show the full microwave topology.

Appendix B.  Contributors

     Italo Busi
     Huawei Technologies
     Email: italo.busi@huawei.com

     Xufeng Liu
     Jabil
     Email: Xufeng_Liu@jabil.com






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Authors' Addresses

   Ye Min (editor)
   Huawei Technologies
   No.1899, Xiyuan Avenue
   Chengdu  611731
   P.R.China

   Email: amy.yemin@huawei.com


   Aihua Guo
   Huawei Technologies

   Email: aihuaguo@huawei.comm


   Jonas Ahlberg
   Ericsson AB
   Lindholmspiren 11
   Goteborg  417 56
   Sweden

   Email: jonas.ahlberg@ericsson.com


   Xi Li
   NEC Laboratories Europe GmbH
   Kurfuersten-Anlage 36
   Heidelberg  69115
   Germany

   Email: Xi.Li@neclab.eu


   Daniela Spreafico
   Nokia - IT
   Via Energy Park, 14
   Vimercate (MI)  20871
   Italy

   Email: daniela.spreafico@nokia.com









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