A YANG data model for Traffic Engineering for Bit Index Explicit Replication (BIER-TE)
draft-ietf-bier-te-yang-02

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BIER WG                                                         Z. Zhang
Internet-Draft                                           ZTE Corporation
Intended status: Standards Track                                 C. Wang
Expires: February 13, 2021                                    Individual
                                                                 R. Chen
                                                         ZTE Corporation
                                                                   F. Hu
                                                              Individual
                                                            M. Sivakumar
                                                        Juniper networks
                                                                 H. Chen
                                                           China Telecom
                                                         August 12, 2020

    A YANG data model for Traffic Engineering for Bit Index Explicit
                         Replication (BIER-TE)
                       draft-ietf-bier-te-yang-02

Abstract

   This document defines a YANG data model for Traffic Engineering for
   Bit Index Explicit Replication (BIER-TE) configuration and operation.

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 February 13, 2021.

Copyright Notice

   Copyright (c) 2020 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

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   (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.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Design of the Data Model  . . . . . . . . . . . . . . . . . .   2
   3.  BIER-TE configuration . . . . . . . . . . . . . . . . . . . .   4
   4.  Notifications . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  RPCs  . . . . . . . . . . . . . . . . . . . . . . . . . . . .   4
   6.  BIER TE YANG model  . . . . . . . . . . . . . . . . . . . . .   4
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  14
   8.  Acknowledgement . . . . . . . . . . . . . . . . . . . . . . .  15
   9.  Normative References  . . . . . . . . . . . . . . . . . . . .  15
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16

1.  Introduction

   [I-D.ietf-bier-te-arch] introduces an architecture for BIER-TE:
   Traffic Engineering for Bit Index Explicit Replication (BIER).  This
   document defines a YANG data model for BIER TE.  The content is in
   keeping with the TE architecture draft.  In addition, this YANG data
   model contains BIER TE frr items of [I-D.eckert-bier-te-frr].

2.  Design of the Data Model

   The BIER TE YANG model includes BIER TE adjancency configuration and
   forwarding items configuration.  Some features can also be used to
   enhance BIER TE function, like ECMP and FRR.

 module: ietf-bier-te
   augment /rt:routing/rt:control-plane-protocols
             /rt:control-plane-protocol:
     +--rw bier-te
        +--rw te-adj
        |  +--rw adj-if* [name]
        |     +--rw name         if:interface-ref
        |     +--rw subdomain* [subdomain-id]
        |     |  +--rw subdomain-id    uint16
        |     |  +--rw si* [si]
        |     |     +--rw si        uint16
        |     |     +--rw adj-id*   uint16
        |     +--rw adj-type?    enumeration

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        +--rw te-fwd
           +--rw subdomain* [subdomain-id]
              +--rw subdomain-id    uint16
              +--rw bsl* [fwd-bsl]
              |  +--rw fwd-bsl    uint16
              |  +--rw si* [si]
              |     +--rw si            uint16
              |     +--rw te-bift-id
              |     |  +--rw type?    enumeration
              |     |  +--rw value    rt-types:mpls-label
              |     +--rw fwd-items* [te-bp]
              |        +--rw te-bp       uint16
              |        +--rw te-ecmp?    boolean {bier-te-ecmp}?
              |        +--rw out-info
              |        |  +--rw out-if-list* [fwd-intf]
              |        |     +--rw fwd-intf          if:interface-ref
              |        |     +--rw dnr-flag?         boolean
              |        |     +--rw fwd-type
              |        |     |  +--rw (fwd-type)
              |        |     |     +--:(connected)
              |        |     |     +--:(routed)
              |        |     |     +--:(local-decap)
              |        |     |     +--:(other)
              |        |     +--rw te-out-bift-id
              |        |        +--rw type?    enumeration
              |        |        +--rw value    rt-types:mpls-label
              |        +--rw te-frr {bier-te-frr}?
              |           +--rw frr-index?
                          -> ../../../../../te-frr-items/btaft/frr-index
              |           +--rw resetbitmask
              |              +--rw bit-string* [index]
              |                 +--rw index      uint8
              |                 +--rw bitmask?   uint32
              +--rw te-frr-items {bier-te-frr}?
                 +--rw btaft* [frr-index]
                    +--rw frr-index     uint16
                    +--rw frr-si        uint16
                    +--rw frr-bsl       uint16
                    +--rw addbitmask
                       +--rw bit-string* [index]
                          +--rw index      uint8
                          +--rw bitmask?   uint32

   notifications:
     +---n bier-te-notification
        +--ro bp-is-zero* [if-index]
           +--ro if-index    if:interface-ref
           +--ro adj-type?   enumeration

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3.  BIER-TE configuration

   The BIER-TE forwarding item is indexed by the combination of sub-
   domain-id, BitStringLength and set identifier.

   One interface can be used in different sub-domain, so the BIER TE
   adjacency information is managed by BIER TE function other than by
   interface itself.

   Because the BIER-TE is controlled by controller now, the information
   about IGP is not defined.  If in the future the IGP is used to carry
   the information about BIER-TE, the IGP extension will be added in
   this document.

4.  Notifications

   If the adjacency id of one adjacency is set to zero, the value is
   invalid.  The notification should be sent to controller and network
   manager.

5.  RPCs

   TBD.

6.  BIER TE YANG model

<CODE BEGINS> file "ietf-bier-te@2020-02-05.yang"
module ietf-bier-te {

  yang-version 1.1;

  namespace "urn:ietf:params:xml:ns:yang:ietf-bier-te";

  prefix bier-te;

  import ietf-routing {
    prefix "rt";
    reference
      "RFC 8349: A YANG Data Model for Routing Management
                 (NMDA Version)";
  }

  import ietf-interfaces {
    prefix "if";
    reference
      "RFC 8343: A YANG Data Model for Interface Management";
  }

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  import ietf-routing-types {
    prefix "rt-types";
    reference
      "RFC 8294: Common YANG Data Types for the Routing Area";
  }

  organization " IETF BIER (Bit Indexed Explicit Replication)
                 Working Group";
  contact
    "WG Web:   <http://tools.ietf.org/wg/bier/>
     WG List:  <mailto:bier@ietf.org>

     Editor:   Zheng Zhang
               <mailto:zhang.zheng@zte.com.cn>
     Editor:   Cui Wang
               <mailto:wang.cui1@zte.com.cn>
     Editor:   Ran Chen
               <mailto:chen.ran@zte.com.cn>
     Editor:   Fangwei Hu
               <mailto:hu.fangwei@zte.com.cn>
     Editor:   Mahesh Sivakumar
               <mailto:masivaku@cisco.com>
     Editor:   Huanan Chen
               <mailto:chenhuanan@gsta.com>
    ";

  description
    "The module defines the YANG definitions for Traffic
     Engineering for Bit Index Explicit Replication (BIER-TE).

     Copyright (c) 2020 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 Simplified 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
     (https://www.rfc-editor.org/info/rfcXXXX); 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)

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     (RFC 8174) when, and only when, they appear in all
     capitals, as shown here.";

  revision 2020-02-05 {
    description
    "Initial revision.";
    reference
      "I-D.ietf-bier-te-arch: Traffic Engineering for Bit Index
       Explicit Replication (BIER-TE)";
  }

  /*
  * Features
  */
  feature bier-te-frr {
    description
      "Support Fast Re-route feature in BIER TE.";
    reference
      "I-D.eckert-bier-te-frr: Protection Methods for BIER-TE";
  }
  feature bier-te-ecmp {
    description
      "Support ECMP feature in BIER TE.";
    reference
      "I-D.ietf-bier-te-arch: Traffic Engineering for Bit Index
       Explicit Replication (BIER-TE), section 3.2.3";
  }

  /*
   * Identities
   */

  identity bier-te {
    base rt:control-plane-protocol;
    description
      "Identity for the Traffic Engineering for Bit Index Explicit
       Replication (BIER-TE).";
    reference
      "I-D.ietf-bier-te-arch: Traffic Engineering for Bit Index
       Explicit Replication (BIER-TE)";
  }

  grouping bit-string {
    description
      "The bit string which each bit represents an adjacency.
       It is encapsulated in BIER header.";
    reference
        "I-D.ietf-bier-te-arch: Traffic Engineering for Bit Index

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         Explicit Replication (BIER-TE), section 3.3.
         RFC8279: Multicast Using Bit Index Explicit Replication
         (BIER).
         RFC8296: Encapsulation for Bit Index Explicit Replication
         (BIER) in MPLS and Non-MPLS Networks.";

    list bit-string {
      key "index";
      description
        "As the definition in RFC 8279, the bit-string lengths are
         64, 128, 256, 512, 1024, 2048, 4096 bits. The according
         encapsulation is defined in RFC8296. BIER-TE uses the
         similar function for bit string.";

      leaf index {
        type uint8 {
          range "2..128";
        }
        description
          "The index of bit-mask. The minimum index value is 64 and
           the corresponding bit string length is 64 bits. The
           maximum index value is 128 and the corresponding
           bit-string length is 4096 bits.";
      }
      leaf bitmask {
        type uint32;
        description "The bit-string in 4-octet units.";
      }
    }
  } // bit-string

  grouping adj-type {
    description "The collection of all possible adjacency type.";

    leaf adj-type {
      type enumeration {
        enum p2p {
          description "Describes p2p adjacency.";
        }
        enum bfer {
          description "Describes bfer adjacency.";
        }
        enum leaf-bfer {
          description
            "Describes leaf-bfer adjacency. There is no next BFR that
             the packet should be forwarded.";
        }
        enum lan {

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          description "Describes lan adjacency.";
        }
        enum spoke {
          description "Describes spoke adjacency of hub-and-spoke.";
        }
        enum ring-clockwise {
          description "Describes clockwise adjacency in ring.";
        }
        enum ring-counterclockwise {
          description "Describes counterclockwise adjacency in ring.";
        }
        enum ecmp {
          description
            "Describes ecmp adjacency. When the type is set to ecmp,
             the corresponding ecmp entry should be used to balance
             the load.";
        }
        enum virtual-link {
          description
            "Describes virtual adjacency between two indirect connect
             nodes.";
        }
        enum other {
          description "Describes other id type of adjacency.";
        }
      }
      description "The collection of all possible adjacency type.";
    }
  } // adj-type

  grouping te-bift-id {
    description "The index of BIER forwarding items. It usually
                 represents the combination of [SD, BSL, SI].";
    leaf type {
      type enumeration {
        enum mpls {
          description
            "The bift-id value is represent the BIER TE mpls
             forwarding plane. It is a mpls label.";
        }
        enum eth {
          description
            "The bift-id value is represent the BIER TE ethernet
             forwarding plane. It is an index of ethernet
             encapsulation.";
        }
        enum other {
          description "Describes other type of te-bift-id.";

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        }
      }
      description "The types of BIER TE bift-id. If this type
                   is not set, mpls is default type.";
    }
    leaf value {
      type rt-types:mpls-label;
      mandatory true;
      description
        "The bift-id value of the forwarding item. It can be a mpls
         label or an index of ethernet encapsulation which is used
         to represent specific combination of [SD, BSL, SI]. The
         ethernet index value is the same range (20bits) as mpls
         label.";
    }
  } // te-bift-id

  grouping te-items {
    description "The BIER TE forwarding items collection.";

    container out-info {
      description
        "The information of out forwarding packets. Includes the
         outbound interface and the bift-id of next hop.";

      list out-if-list {
        key "fwd-intf";
        description
          "The outbound interface information for forwarding.";

        leaf fwd-intf {
          type if:interface-ref;
          mandatory true;
          description
            "The out interface of this forwarding item.";
        }
        leaf dnr-flag {
          type boolean;
          description
            "When the flag is set to 1, the BP of adjacency should not
             be reset when packet copies are created. The flag makes
             sense only when the forwarding type is 'connected'.";
        }
        container fwd-type {
          description
            "The collection of all possible forwarding types.";
          choice fwd-type {
            mandatory true;

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            case connected {
              description
                "The forwarding type is connected. Mostly connected
                 interfaces.";
            }
            case routed {
              description
                "The forwarding type is routed. Mostly not connected
                 interfaces.";
            }
            case local-decap {
              description
                "Means that the packet should be decapsulated and
                 forward out of BIER domain.";
             }
            case other {
              description
                "Means that the packet should be discarded.";
            }
            description
              "The collection of all possible forwarding types.";
          }
        } // fwd-type

        container te-out-bift-id {
          description
            "The bift-id information corresponding to a specific
             outbound interface.";
          uses te-bift-id;
        }
      }
    }
  } // te-items

  /*
  * data nodes
  */
  augment "/rt:routing/rt:control-plane-protocols/"
       +"rt:control-plane-protocol" {
    description "The BIER TE information.";
    container bier-te {
      description "The BIER TE information container.";

      container te-adj {
        description "The BIER TE adjacency information.";
        list adj-if {
          key "name";
          description "List of BIER-TE interfaces.";

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          leaf name {
            type if:interface-ref;
            description "Interface name reference.";
          }
          list subdomain {
            key "subdomain-id";
            description
              "The sub-domain which the interface belongs to.
               One interface can belong to many subdomains.";

            leaf subdomain-id {
              type uint16;
              description "The sub-domain-id of this sub-domain.";
              reference
                "RFC 8279: Multicast Using Bit Index Explicit
                 Replication (BIER)";
            }
            list si {
              key "si";
              description "The set identifier value.";

              leaf si{
                type uint16;
                mandatory true;
                description
                  "The set identifier of this forwarding item.";
              }
              leaf-list adj-id {
                type uint16;
                description "The ID of an adjacency.";
              }
            }
          }
          uses adj-type;
        }
      } // te-adj

      container te-fwd {
        description "The BIER TE forwarding information.";

        list subdomain {
          key "subdomain-id";
          description
            "The sub-domain which the interface belongs to.
             One interface can belong to many subdomains.";

          leaf subdomain-id {
            type uint16;

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            description "The sub-domain-id of this sub-domain.";
            reference
              "RFC 8279: Multicast Using Bit Index Explicit
               Replication (BIER)";
          }
          list bsl {
            key "fwd-bsl";
            description "The forwarding items in one BSL.";
            leaf fwd-bsl {
              type uint16;
              description "The value of bitstringlength.";
            }
              list si {
                key "si";
                description
                  "The forwarding items in one combination of SD,
                   BSL and SI.";
                leaf si{
                  type uint16;
                  mandatory true;
                  description
                    "The set identifier of this forwarding item.";
                }
                            container te-bift-id {
                  description
                    "The bift-id which is used to locate the specific
                     forwarding item.";
                  uses te-bift-id;
                }

                list fwd-items {
                  key "te-bp";
                  description
                    "The forwarding information of one BIER TE item.";
                  leaf te-bp {
                    type uint16;
                    mandatory true;
                    description
                      "The bit index of a BIER TE forwarding item.";
                  }

                  leaf te-ecmp {
                    if-feature bier-te-ecmp;
                    type boolean;
                    description
                      "The list of the ecmp paths. When the type of
                       BP is set to ecmp, this interface ecmp list
                       should be used to balance the load on each

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                       interface.";
                  }
                  uses te-items;

                  container te-frr {
                    if-feature bier-te-frr;
                    leaf frr-index {
                      type leafref {
                        path "../../../../../" +
                             "te-frr-items/btaft/frr-index";
                      }
                      description "The index of this frr path.";
                    }
                    container resetbitmask {
                      description
                        "The deleting bitmask of the forwarding item.";
                      uses bit-string;
                    }
                    description
                      "If this link is protected, frr items can be used to
                       forward flows when this link is down.";
                  } // te-frr
                } // fwd-items
              } // si
          } // bsl

          container te-frr-items {
            if-feature bier-te-frr;
            description "The TE fast re-route information.";
              list btaft {
              key "frr-index";
              description
                "The index of the frr paths. This item can be used
                 for multiple links protection in different SI.";
              leaf frr-index {
                type uint16;
                mandatory true;
                description "The frr item index.";
              }
              leaf frr-si{
                type uint16;
                mandatory true;
                description
                  "The set identifier of this forwarding item.";
              }
              leaf frr-bsl {
                type uint16;
                mandatory true;

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                description "The value of bitstringlength.";
              }
              container addbitmask {
                description
                  "The adding bitmask of the forwarding item.
                   This item should be merged into the packet's
                   bit-string.";
                uses bit-string;
              }
            } // btaft
          } // te-frr-items
        } // subdomain
      } // te-fwd
    } // bier-te
  }

  /*
  * Notifications
  */
  notification bier-te-notification {
      description
        "The notification is sent when a condition changes.";
      list bp-is-zero {
          key "if-index";
          description "The adjacency id is zero. It is invalid.";
          leaf if-index {
              type if:interface-ref;
              description "The adjacency id is zero.";
          }
          uses adj-type;
      }
  }
}
<CODE ENDS>

7.  IANA Considerations

   The IANA is requested to assign two new URIs from the IETF XML
   registry ([RFC3688]).  Authors are suggesting the following URI:

   URI: urn:ietf:params:xml:ns:yang:ietf-bier-te

   Registrant Contact: BIER WG

   XML: N/A, the requested URI is an XML namespace

   This document also requests one new YANG module name in the YANG
   Module Names registry ([RFC6020]) with the following suggestion:

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   name: ietf-bier-te

   namespace: urn:ietf:params:xml:ns:yang:ietf-bier-te

   prefix: bier-te

   reference: RFC XXXX

8.  Acknowledgement

   The authors would like to thank Min Gu (gumin20181129@163.com) for
   her testing, verification and valuable suggestion.  And the authors
   would like to thank Benjamin R for his valuable comments.

9.  Normative References

   [I-D.eckert-bier-te-frr]
              Eckert, T., Cauchie, G., Braun, W., and M. Menth,
              "Protection Methods for BIER-TE", draft-eckert-bier-te-
              frr-03 (work in progress), March 2018.

   [I-D.ietf-bier-bier-yang]
              Chen, R., hu, f., Zhang, Z., dai.xianxian@zte.com.cn, d.,
              and M. Sivakumar, "YANG Data Model for BIER Protocol",
              draft-ietf-bier-bier-yang-06 (work in progress), February
              2020.

   [I-D.ietf-bier-te-arch]
              Eckert, T., Cauchie, G., and M. Menth, "Tree Engineering
              for Bit Index Explicit Replication (BIER-TE)", draft-ietf-
              bier-te-arch-08 (work in progress), July 2020.

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

   [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>.

   [RFC6087]  Bierman, A., "Guidelines for Authors and Reviewers of YANG
              Data Model Documents", RFC 6087, DOI 10.17487/RFC6087,
              January 2011, <https://www.rfc-editor.org/info/rfc6087>.

   [RFC7223]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 7223, DOI 10.17487/RFC7223, May 2014,
              <https://www.rfc-editor.org/info/rfc7223>.

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   [RFC8279]  Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
              Przygienda, T., and S. Aldrin, "Multicast Using Bit Index
              Explicit Replication (BIER)", RFC 8279,
              DOI 10.17487/RFC8279, November 2017,
              <https://www.rfc-editor.org/info/rfc8279>.

   [RFC8296]  Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A.,
              Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation
              for Bit Index Explicit Replication (BIER) in MPLS and Non-
              MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January
              2018, <https://www.rfc-editor.org/info/rfc8296>.

   [RFC8349]  Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for
              Routing Management (NMDA Version)", RFC 8349,
              DOI 10.17487/RFC8349, March 2018,
              <https://www.rfc-editor.org/info/rfc8349>.

Authors' Addresses

   Zheng(Sandy) Zhang
   ZTE Corporation
   Nanjing
   China

   Email: zhang.zheng@zte.com.cn

   Cui(Linda) Wang
   Individual

   Email: lindawangjoy@gmail.com

   Ran Chen
   ZTE Corporation
   Nanjing
   China

   Email: chen.ran@zte.com.cn

   Fangwei Hu
   Individual
   Shanghai
   China

   Email: hufwei@gmail.com

Zhang, et al.           Expires February 13, 2021              [Page 16]
Internet-Draft             BIER TE YANG Model                August 2020

   Mahesh Sivakumar
   Juniper networks
   1133 Innovation Way
   Sunnyvale, CALIFORNIA 94089
   United States

   Email: sivakumar.mahesh@gmail.com

   Huanan Chen
   China Telecom
   109 West Zhongshan Ave
   Guangzhou, Guangdong  510630
   China

   Phone: +86 20 38639346
   Email: chenhuanan@gsta.com

Zhang, et al.           Expires February 13, 2021              [Page 17]