TEAS Working Group                                               T. Saad
Internet-Draft                                                 V. Beeram
Intended status: Standards Track                        Juniper Networks
Expires: September 8, 2022                                        B. Wen
                                                                 Comcast
                                                           D. Ceccarelli
                                                                Ericsson
                                                                 S. Peng
                                                                 R. Chen
                                                         ZTE Corporation
                                                           LM. Contreras
                                                              Telefonica
                                                                  X. Liu
                                                         IBM Corporation
                                                           March 7, 2022


         YANG Data Model for Network Resource Partition Policy
                 draft-bestbar-teas-yang-nrp-policy-00

Abstract

   A Network Resource Partition (NRP) is a collection of resources
   identified in the underlay network to support services (like IETF
   Network Slices) that need logical network structures with required
   characteristics to be created.  An NRP policy is a policy construct
   that enables instantiation of mechanisms in support of service
   specific control and data plane behaviors on select topological
   elements associated with the NRP.  This document defines a YANG data
   model for the management of NRP policies on NRP capable nodes and
   controllers in IP/MPLS networks.

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.

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




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   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 September 8, 2022.

Copyright Notice

   Copyright (c) 2022 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.  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  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   4
     1.2.  Tree Structure  . . . . . . . . . . . . . . . . . . . . .   4
   2.  NRP Policy Data Model . . . . . . . . . . . . . . . . . . . .   4
     2.1.  Model Usage . . . . . . . . . . . . . . . . . . . . . . .   4
     2.2.  Model Structure . . . . . . . . . . . . . . . . . . . . .   4
     2.3.  NRP Policies  . . . . . . . . . . . . . . . . . . . . . .   5
       2.3.1.  Resource Reservation  . . . . . . . . . . . . . . . .   5
       2.3.2.  Flow Aggregate Selector . . . . . . . . . . . . . . .   6
       2.3.3.  Per-Hop-Behavior  . . . . . . . . . . . . . . . . . .   7
       2.3.4.  Topology  . . . . . . . . . . . . . . . . . . . . . .   7
     2.4.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .   9
   3.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  19
   4.  Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  19
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  19
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  20
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  20
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  20
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  22
   Appendix A.  Complete Model Tree Structure  . . . . . . . . . . .  22
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  25



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1.  Introduction

   An IETF Network Slice [I-D.ietf-teas-ietf-network-slices] is a
   service that provides connectivity coupled with a set of specific
   commitments of network resources between a number of endpoints over a
   shared underlay network.  The IETF Network Slice service is expressed
   in terms of one or more connectivity constructs.  One or more
   connectivity constructs from one or more IETF Network Slices are
   mapped to a set of network resources called a Network Resource
   Partition (NRP).  An NRP is a collection of resources identified in
   the underlay network to support the IETF Network Slice service (or
   any other service that needs logical network structures with required
   characteristics to be created).  An NRP Policy
   [I-D.bestbar-teas-ns-packet] is a policy construct that enables
   instantiation of mechanisms in support of service specific control
   and data plane behaviors on select topological elements associated
   with the NRP.

   An NRP policy specifies the rules for determining the topology
   associated with the NRP and dictates how an NRP can be realized in
   IP/MPLS networks using one of three modes.  The NRP policy dictates
   if the partitioning of the shared network resources can be achieved
   in (a) just the data plane or in (b) just the control plane or in (c)
   both the control and data planes.

   The NRP policy modes (a) and (c) require the forwarding engine on
   each NRP capable node to identify the traffic belonging to a specific
   flow aggregate and to apply the corresponding Per-Hop Behavior (PHB)
   that determines the forwarding treatment of the packets belonging to
   the flow aggregate.  The identification of the flow aggregate that
   the packet belongs to and the corresponding forwarding treatment that
   needs to be applied to the packet is dictated by the NRP policy.
   When catering to IETF Network Slices, this flow aggregate is referred
   to as the Slice-Flow Aggregate [I-D.bestbar-teas-ns-packet] and
   comprises of traffic streams from one or more connectivity constructs
   (belonging to one or more IETF network slices) mapped to a specific
   NRP.

   The NRP policy modes (b) and (c) require the distributed/centralized
   resource reservation manager in the control plane to manage NRP
   resource reservation.  The provisions for enabling NRP state aware
   traffic engineering (NRP-TE) [I-D.bestbar-teas-ns-packet] are
   dictated by the NRP policy.

   This document defines a YANG data model for the management of NRP
   policies on NRP capable nodes and controllers in IP/MPLS networks.





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1.1.  Terminology

   The terminology for describing YANG data models is found in
   [RFC7950].

   The reader is expected to be familiar with the terminology specified
   in [I-D.ietf-teas-ietf-network-slices] and
   [I-D.bestbar-teas-ns-packet].

1.2.  Tree Structure

   A simplified graphical representation of the data model is presented
   in Appendix A of this document.  The tree format defined in [RFC8340]
   is used for the YANG data model tree representation.

2.  NRP Policy Data Model

2.1.  Model Usage

   A controller that consumes the IETF Network Slice service requests
   determines which specific connectivity constructs from one or more
   slices can be grouped together.  This could be based on a specific
   set of SLOs and SLEs, or on any administrative or operational reason.
   A controller function that has visibility of the underlay network and
   its resources maps these connectivity constructs onto the NRP.  It
   also constructs and distributes the network wide consistent NRP
   policy (using the data model defined in this document) to the
   relevant NRP capable nodes and controllers.

2.2.  Model Structure

   The high-level model structure defined by this document is as shown
   below:


















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   module: ietf-nrp-policy
     augment /nw:networks:
       +--rw nrp-policies
          +--rw nrp-policy* [name]
             +--rw name                    string
             +--rw nrp-id?                 uint32
             +--rw resource-reservation
             |  +  ............
             +--rw flow-agg-selector
             |  +  ............
             +--rw phb?                    string
             +--rw topology
                +--rw filters
                   +--rw filter* [filter-ref]
                   +  ............
                   +--rw resource-reservation
                   |  +  ............
                   +--rw flow-agg-selector
                   |  +  ............
                   +--rw phb?                    string


   The 'networks' container from the 'ietf-network' module [RFC8345]
   provides a placeholder for an inventory of nodes in the network.
   This container is augmented to carry a set of NRP policies.

2.3.  NRP Policies

   The 'nrp-policies' container carries a list of NRP policies.  Each
   'nrp-policy' entry is identified by a name and holds the set of
   attributes needed to instantiate the NRP.  Each entry also carries an
   'nrp-id' leaf which uniquely identifies the NRP created by the
   enforcement of this policy.  The key elements of each nrp-policy
   entry are discussed in the following sub-sections.

2.3.1.  Resource Reservation

   The 'resource-reservation' container carries data nodes that are used
   to support NRP state aware bandwidth engineering.  The data nodes in
   this container facilitate preference-based preemption of NRP state
   aware TE paths, sharing of resources amongst a group of NRPs and
   backup path bandwidth protection.









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              +--rw resource-reservation
              |  +--rw preference?                        uint16
              |  +--rw (max-bw-type)?
              |  |  +--:(bw-value)
              |  |  |  +--rw maximum-bandwidth?           uint64
              |  |  +--:(bw-percentage)
              |  |     +--rw maximum-bandwidth-percent?
              |  |             rt-types:percentage
              |  +--rw shared-resource-groups*            uint32
              |  +--rw protection
              |     +--rw backup-nrp-id?                    uint32
              |     +--rw (backup-bw-type)?
              |        +--:(backup-bw-value)
              |        |  +--rw backup-bandwidth?           uint64
              |        +--:(backup-bw-percentage)
              |           +--rw backup-bandwidth-percent?
              |                   rt-types:percentage

2.3.2.  Flow Aggregate Selector

   The 'flow-agg-selector' container carries data nodes that specify the
   rules for identifying which packets belong to the flow aggregate that
   this NRP caters to.




























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             +--rw flow-agg-selector
             |  +--rw mpls
             |  |  +--rw (fas-type)?
             |  |     +--:(label)
             |  |     |  +--rw (specification-type)?
             |  |     |     +--:(derived)
             |  |     |     |  +--rw forwarding-label?        empty
             |  |     |     +--:(explicit)
             |  |     |        +--rw label?
             |  |     |        |       rt-types:mpls-label
             |  |     |        +--rw label-position?
             |  |     |        |       identityref
             |  |     |        +--rw label-position-offset?   uint8
             |  |     +--:(label-ranges)
             |  |        +--rw label-range* [index]
             |  |           +--rw index                    string
             |  |           +--rw start-label?
             |  |           |       rt-types:mpls-label
             |  |           +--rw end-label?
             |  |           |       rt-types:mpls-label
             |  |           +--rw label-position?          identityref
             |  |           +--rw label-position-offset?   uint8
             |  +--rw ipv4
             |  |  +--rw destination-prefix*   inet:ipv4-prefix
             |  +--rw ipv6
             |  |  +--rw (fas-type)?
             |  |     +--:(ipv6-destination)
             |  |     |  +--rw destination-prefix*   inet:ipv6-prefix
             |  |     +--:(ipv6-hbh-eh)
             |  |        +--rw fas-hbh-eh*           uint32
             |  +--rw acl-ref*   nrp-policy-acl-ref

2.3.3.  Per-Hop-Behavior

   The 'phb' leaf carries a name of a PHB profile available on the
   topological element where the policy is being enforced.

             +--rw phb?                    string

2.3.4.  Topology

   The 'topology' container consists of a list of filters where each
   entry references a topology filter
   [I-D.bestbar-teas-yang-topology-filter].  The resultant topology from
   the union of these filters is referred to as the NRP topology.  The
   topological elements that satisfy the membership criteria can
   optionally override the default resource-reservation, flow-agg-
   selector and phb specific leafs.



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             +--rw topology
                +--rw filters
                   +--rw filter* [filter-ref]
                      +--rw filter-ref
                      |       nrp-policy-topo-filter-ref
                      +--rw resource-reservation
                      |  +--rw preference?                        uint16
                      |  +--rw (max-bw-type)?
                      |  |  +--:(bw-value)
                      |  |  |  +--rw maximum-bandwidth?           uint64
                      |  |  +--:(bw-percentage)
                      |  |     +--rw maximum-bandwidth-percent?
                      |  |             rt-types:percentage
                      |  +--rw shared-resource-groups*            uint32
                      |  +--rw protection
                      |     +--rw backup-nrp-id?
                      |     |       uint32
                      |     +--rw (backup-bw-type)?
                      |        +--:(backup-bw-value)
                      |        |  +--rw backup-bandwidth?
                      |        |          uint64
                      |        +--:(backup-bw-percentage)
                      |           +--rw backup-bandwidth-percent?
                      |                   rt-types:percentage
                      +--rw flow-agg-selector
                      |  +--rw mpls
                      |  |  +--rw (fas-type)?
                      |  |     +--:(label)
                      |  |     |  +--rw (specification-type)?
                      |  |     |     +--:(derived)
                      |  |     |     |  +--rw forwarding-label?
                      |  |     |     |          empty
                      |  |     |     +--:(explicit)
                      |  |     |        +--rw label?
                      |  |     |        |       rt-types:mpls-label
                      |  |     |        +--rw label-position?
                      |  |     |        |       identityref
                      |  |     |        +--rw label-position-offset?
                      |  |     |                uint8
                      |  |     +--:(label-ranges)
                      |  |        +--rw label-range* [index]
                      |  |           +--rw index
                      |  |           |       string
                      |  |           +--rw start-label?
                      |  |           |       rt-types:mpls-label
                      |  |           +--rw end-label?
                      |  |           |       rt-types:mpls-label
                      |  |           +--rw label-position?



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                      |  |           |       identityref
                      |  |           +--rw label-position-offset?
                      |  |                   uint8
                      |  +--rw ipv4
                      |  |  +--rw destination-prefix*   inet:ipv4-prefix
                      |  +--rw ipv6
                      |  |  +--rw (fas-type)?
                      |  |     +--:(ipv6-destination)
                      |  |     |  +--rw destination-prefix*
                      |  |     |          inet:ipv6-prefix
                      |  |     +--:(ipv6-hbh-eh)
                      |  |        +--rw fas-hbh-eh*           uint32
                      |  +--rw acl-ref*   nrp-policy-acl-ref
                      +--rw phb?                    string

2.4.  YANG Module

   <CODE BEGINS> file "ietf-nrp-policy@2022-03-07.yang"
   module ietf-nrp-policy {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-nrp-policy";
     prefix nrp-pol;

     import ietf-inet-types {
       prefix inet;
       reference
         "RFC 6991: Common YANG Data Types";
     }
     import ietf-routing-types {
       prefix rt-types;
       reference
         "RFC 8294: Common YANG Data Types for the Routing Area";
     }
     import ietf-network {
       prefix nw;
       reference
         "RFC 8345: A YANG Data Model for Network Topologies";
     }
     import ietf-access-control-list {
       prefix acl;
       reference
         "RFC 8519: YANG Data Model for Network Access Control Lists
          (ACLs)";
     }
     import ietf-topology-filter {
       prefix topo-filt;
       reference
         "draft-bestbar-teas-yang-topology-filter: YANG Data Model



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          for Topology Filter";
     }

     organization
       "IETF Traffic Engineering Architecture and Signaling (TEAS)
        Working Group.";
     contact
       "WG Web:   <http://tools.ietf.org/wg/teas/>
        WG List:  <mailto:teas@ietf.org>

        Editor:   Vishnu Pavan Beeram
                  <mailto:vbeeram@juniper.net>

        Editor:   Tarek Saad
                  <mailto:tsaad@juniper.net>

        Editor:   Bin Wen
                  <mailto:Bin_Wen@cable.comcast.com>

        Editor:   Daniele Ceccarelli
                  <mailto:daniele.ceccarelli@ericsson.com>

        Editor:   Shaofu Peng
                  <mailto:peng.shaofu@zte.com.cn>

        Editor:   Ran Chen
                  <mailto:chen.ran@zte.com.cn>

        Editor:   Luis M. Contreras
                  <mailto:luismiguel.contrerasmurillo@telefonica.com>

        Editor:   Xufeng Liu
                  <mailto:xufeng.liu.ietf@gmail.com>";
     description
       "This YANG module defines a data model for managing Network
        Resource Partition Policies on Network Resource Partition
        capable nodes and controllers.

        Copyright (c) 2022 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).




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

     revision 2022-03-07 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: YANG Data Model for Network Resource Partition
          Policies.";
     }

     /*
      * I D E N T I T I E S
      */

     /*
      * Identity:
      * MPLS Flow Aggregate Selector (FAS) Label Position Type.
      */

     identity fas-mpls-label-position-type {
       description
         "Base identity for the position of the MPLS FAS label.";
     }

     identity fas-mpls-label-position-top {
       base fas-mpls-label-position-type;
       description
         "MPLS FAS label is at the top of the label stack.";
     }

     identity fas-mpls-label-position-bottom {
       base fas-mpls-label-position-type;
       description
         "MPLS FAS label is either at the bottom or at a specific
          offset from the bottom of the label stack.";
     }

     identity fas-mpls-label-position-indicator {
       base fas-mpls-label-position-type;
       description
         "MPLS FAS is preceded by a special purpose
          indicator label in the label stack.";
     }


     /*
      * T Y P E D E F S



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      */

     typedef nrp-policy-acl-ref {
       type leafref {
         path "/acl:acls/acl:acl/acl:name";
       }
       description
         "This type is used to reference an ACL.";
     }

     typedef nrp-policy-topo-filter-ref {
       type leafref {
         path "/nw:networks/topo-filt:topology-filters/"
            + "topo-filt:topology-filter/topo-filt:name";
       }
       description
         "This type is used to reference a Topology Filter.";
     }

     /*
      * G R O U P I N G S
      */

     /*
      * Grouping - MPLS FAS label location specific fields
      */

     grouping nrp-pol-fas-mpls-label-location {
       description
         "Grouping for MPLS FAS label location specific fields.";
       leaf label-position {
         type identityref {
           base fas-mpls-label-position-type;
         }
         description
           "MPLS FAS label position.";
       }
       leaf label-position-offset {
         when "derived-from-or-self(../label-position,"
            + "'nrp-pol:fas-mpls-label-position-bottom')" {
           description
             "MPLS label position offset is relevant only when the
              label-position is set to 'bottom'.";
         }
         type uint8;
         description
           "MPLS label position offset.";
       }



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     }

     /*
      * Grouping - Flow-Aggregate Selector (FAS)
      */

     grouping nrp-pol-flow-agg-selector {
       description
         "Grouping for Flow-Aggregate Selector (FAS).";
       container flow-agg-selector {
         description
           "Container for FAS.";
         container mpls {
           description
             "Container for MPLS FAS.";
           choice fas-type {
             description
               "Choices for MPLS FAS.";
             case label {
               choice specification-type {
                 description
                   "Choices for MPLS label specification.";
                 case derived {
                   leaf forwarding-label {
                     type empty;
                     description
                       "MPLS FAS Label is derived from
                        forwarding label.";
                   }
                 }
                 case explicit {
                   leaf label {
                     type rt-types:mpls-label;
                     description
                       "MPLS FAS Label is explicitly
                        specified.";
                   }
                   uses nrp-pol-fas-mpls-label-location;
                 }
               }
             }
             case label-ranges {
               list label-range {
                 key "index";
                 unique "start-label end-label";
                 description
                   "Any label from the specified set of MPLS label
                    ranges can be used as the FAS.";



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                 leaf index {
                   type string;
                   description
                     "A string that uniquely identifies a label
                      range.";
                 }
                 leaf start-label {
                   type rt-types:mpls-label;
                   must '. <= ../end-label' {
                     error-message
                       "The start-label must be less than or equal "
                       + "to end-label";
                   }
                   description
                     "Label-range start.";
                 }
                 leaf end-label {
                   type rt-types:mpls-label;
                   must '. >= ../start-label' {
                     error-message
                       "The end-label must be greater than or equal "
                       + "to start-label";
                   }
                   description
                     "Label-range end.";
                 }
                 uses nrp-pol-fas-mpls-label-location;
               }
             }
           }
         }
         container ipv4 {
           description
             "Container for IPv4 FAS.";
           leaf-list destination-prefix {
             type inet:ipv4-prefix;
             description
               "Any prefix from the specified set of IPv4
                destination prefixes can be the FAS.";
           }
         }
         container ipv6 {
           description
             "Container for IPv6 FAS.";
           choice fas-type {
             description
               "Choices for IPv6 FAS.";
             case ipv6-destination {



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               leaf-list destination-prefix {
                 type inet:ipv6-prefix;
                 description
                   "Any prefix from the specified set of IPv6
                    destination prefixes can be the FAS.";
               }
             }
             case ipv6-hbh-eh {
               leaf-list fas-hbh-eh {
                 type uint32;
                 description
                   "Set of FAS values carried in Hop-by-Hop
                    Option of IPv6 extension header.";
               }
             }
           }
         }
         leaf-list acl-ref {
           type nrp-policy-acl-ref;
           description
             "Flow Aggregate selection is done based on the
              specified list of ACLs.";
         }
       }
     }

     /*
      * Grouping - NRP Policy Resource Reservation
      */

     grouping nrp-pol-resource-reservation {
       description
         "Grouping for NRP policy resource reservation.";
       container resource-reservation {
         description
           "Container for NRP policy resource reservation.";
         leaf preference {
           type uint16;
           description
             "Control plane preference for the corresponding
              Network Resource Partition (NRP). A higher
              preference indicates a more favorable resource
              reservation than a lower preference.";
         }
         choice max-bw-type {
           description
             "Choice of maximum bandwidth specification.";
           case bw-value {



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             leaf maximum-bandwidth {
               type uint64;
               description
                 "The maximum bandwidth allocated to an NRP
                  - specified as absolute value.";
             }
           }
           case bw-percentage {
             leaf maximum-bandwidth-percent {
               type rt-types:percentage;
               description
                 "The maximum bandwidth allocated to an NRP
                  - specified as percentage of link
                  capacity.";
             }
           }
         }
         leaf-list shared-resource-groups {
           type uint32;
           description
             "List of shared resource groups that an NRP
              shares its allocated resources with.";
         }
         container protection {
           description
             "Container for NRP protection reservation.";
           leaf backup-nrp-id {
             type uint32;
             description
               "The ID that identifies the NRP used for
                backup paths that protect primary paths
                setup over a specific NRP.";
           }
           choice backup-bw-type {
             description
               "Choice of backup bandwidth specification.";
             case backup-bw-value {
               leaf backup-bandwidth {
                 type uint64;
                 description
                   "The maximum bandwidth on a network resource that
                    is allocated for backup traffic - specified as
                    absolute value.";
               }
             }
             case backup-bw-percentage {
               leaf backup-bandwidth-percent {
                 type rt-types:percentage;



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                 description
                   "The maximum bandwidth on a network resource that
                    is allocated for backup traffic - specified as
                    percentage of the link capacity.";
               }
             }
           }
         }
       }
     }

     /*
      * Grouping - NRP policy - PHB (NRP-PHB)
      */

     grouping nrp-pol-phb {
       description
         "Grouping for NRP-PHB.";
       leaf phb {
         type string;
         description
           "PHB profile identifier.";
       }
     }

     /*
      * Grouping - NRP Policy - Topology
      */

     grouping nrp-pol-topology {
       description
         "Grouping for NRP topology.";
       container topology {
         description
           "Container for NRP topology.";
         container filters {
           description
             "Container for filters.";
           list filter {
             key "filter-ref";
             description
               "List of filters.";
             leaf filter-ref {
               type nrp-policy-topo-filter-ref;
               description
                 "Reference to a specific topology filter from the
                  list of global topology filters.";
             }



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             uses nrp-pol-resource-reservation;
             uses nrp-pol-flow-agg-selector;
             uses nrp-pol-phb;
           }
         }
       }
     }


     /*
      * Grouping - Network Resource Partition Policies
      */

     grouping nrp-pol {
       description
         "Grouping for NRP policies.";
       container nrp-policies {
         description
           "Container for nrp policies.";
         list nrp-policy {
           key "name";
           unique "nrp-id";
           description
             "List of NRP policies.";
           leaf name {
             type string;
             description
               "A string that uniquely identifies the NRP policy.";
           }
           leaf nrp-id {
             type uint32;
             description
               "A 32-bit ID that uniquely identifies the NRP
                created by the enforcement of this NRP policy.";
           }
           uses nrp-pol-resource-reservation;
           uses nrp-pol-flow-agg-selector;
           uses nrp-pol-phb;
           uses nrp-pol-topology;
         }
       }
     }

     /*
      * Augment - Network Resource Partition Policies.
      */
     augment "/nw:networks" {
       description



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         "Augment networks with network resource partition
          policies.";
       uses nrp-pol;
     }
   }
   <CODE ENDS>

3.  Acknowledgements

   The authors would like to thank Krzysztof Szarkowicz for his input
   from discussions.

4.  Contributors

   The following individuals contributed to this document:

   Colby Barth
   Juniper Networks
   Email: cbarth@juniper.net

   Srihari R.  Sangli
   Juniper Networks
   Email: ssangli@juniper.net

   Chandra Ramachandran
   Juniper Networks
   Email: csekar@juniper.net


5.  IANA Considerations

   This document registers the following URI in the IETF XML registry
   [RFC3688].  Following the format in [RFC3688], the following
   registration is requested to be made.

   URI: urn:ietf:params:xml:ns:yang:ietf-nrp-policy
   Registrant Contact: The TEAS WG of the IETF.
   XML: N/A, the requested URI is an XML namespace.

   This document registers a YANG module in the YANG Module Names
   registry [RFC6020].

   name: ietf-nrp-policy
   namespace: urn:ietf:params:xml:ns:yang:ietf-nrp-policy
   prefix: sl-pol
   reference: RFCXXXX





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6.  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].  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
   [RFC8446].

   The Network Configuration Access Control Model (NACM) [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.

   The data nodes defined in this YANG module that are
   writable/creatable/deletable (i.e., config true, which is the
   default) 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:

   *  "/networks/nrp-policies": This subtree specifies the
      configurations for NRP policies on a given network element.  By
      manipulating these data nodes, a malicious attacker may cause
      unauthorized and improper behavior to be provided for the flow
      aggregate traffic on the network element.

   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:

   *  "/networks/nrp-policies": Unauthorized access to this subtree can
      disclose the NRP policy definitions on the network element.

7.  References

7.1.  Normative References

   [I-D.bestbar-teas-ns-packet]
              Saad, T., Beeram, V. P., Dong, J., Wen, B., Ceccarelli,
              D., Halpern, J., Peng, S., Chen, R., Liu, X., Contreras,
              L. M., Rokui, R., and L. Jalil, "Realizing Network Slices
              in IP/MPLS Networks", draft-bestbar-teas-ns-packet-08
              (work in progress), February 2022.



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   [I-D.bestbar-teas-yang-topology-filter]
              Beeram, V. P., Saad, T., Gandhi, R., and X. Liu, "YANG
              Data Model for Topology Filter", draft-bestbar-teas-yang-
              topology-filter-02 (work in progress), October 2021.

   [I-D.ietf-teas-ietf-network-slices]
              Farrel, A., Drake, J., Rokui, R., Homma, S., Makhijani,
              K., Contreras, L. M., and J. Tantsura, "Framework for IETF
              Network Slices", draft-ietf-teas-ietf-network-slices-07
              (work in progress), March 2022.

   [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>.

   [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>.

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

   [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>.

   [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/info/rfc8174>.






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   [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>.

   [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>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

7.2.  Informative References

   [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/info/rfc8340>.

Appendix A.  Complete Model Tree Structure

   module: ietf-nrp-policy
     augment /nw:networks:
       +--rw nrp-policies
          +--rw nrp-policy* [name]
             +--rw name                    string
             +--rw nrp-id?                 uint32
             +--rw resource-reservation
             |  +--rw preference?                        uint16
             |  +--rw (max-bw-type)?
             |  |  +--:(bw-value)
             |  |  |  +--rw maximum-bandwidth?           uint64
             |  |  +--:(bw-percentage)
             |  |     +--rw maximum-bandwidth-percent?
             |  |             rt-types:percentage
             |  +--rw shared-resource-groups*            uint32
             |  +--rw protection
             |     +--rw backup-nrp-id?                    uint32
             |     +--rw (backup-bw-type)?
             |        +--:(backup-bw-value)
             |        |  +--rw backup-bandwidth?           uint64
             |        +--:(backup-bw-percentage)
             |           +--rw backup-bandwidth-percent?
             |                   rt-types:percentage
             +--rw flow-agg-selector
             |  +--rw mpls
             |  |  +--rw (fas-type)?



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             |  |     +--:(label)
             |  |     |  +--rw (specification-type)?
             |  |     |     +--:(derived)
             |  |     |     |  +--rw forwarding-label?        empty
             |  |     |     +--:(explicit)
             |  |     |        +--rw label?
             |  |     |        |       rt-types:mpls-label
             |  |     |        +--rw label-position?
             |  |     |        |       identityref
             |  |     |        +--rw label-position-offset?   uint8
             |  |     +--:(label-ranges)
             |  |        +--rw label-range* [index]
             |  |           +--rw index                    string
             |  |           +--rw start-label?
             |  |           |       rt-types:mpls-label
             |  |           +--rw end-label?
             |  |           |       rt-types:mpls-label
             |  |           +--rw label-position?          identityref
             |  |           +--rw label-position-offset?   uint8
             |  +--rw ipv4
             |  |  +--rw destination-prefix*   inet:ipv4-prefix
             |  +--rw ipv6
             |  |  +--rw (fas-type)?
             |  |     +--:(ipv6-destination)
             |  |     |  +--rw destination-prefix*   inet:ipv6-prefix
             |  |     +--:(ipv6-hbh-eh)
             |  |        +--rw fas-hbh-eh*           uint32
             |  +--rw acl-ref*   nrp-policy-acl-ref
             +--rw phb?                    string
             +--rw topology
                +--rw filters
                   +--rw filter* [filter-ref]
                      +--rw filter-ref
                      |       nrp-policy-topo-filter-ref
                      +--rw resource-reservation
                      |  +--rw preference?                        uint16
                      |  +--rw (max-bw-type)?
                      |  |  +--:(bw-value)
                      |  |  |  +--rw maximum-bandwidth?           uint64
                      |  |  +--:(bw-percentage)
                      |  |     +--rw maximum-bandwidth-percent?
                      |  |             rt-types:percentage
                      |  +--rw shared-resource-groups*            uint32
                      |  +--rw protection
                      |     +--rw backup-nrp-id?
                      |     |       uint32
                      |     +--rw (backup-bw-type)?
                      |        +--:(backup-bw-value)



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                      |        |  +--rw backup-bandwidth?
                      |        |          uint64
                      |        +--:(backup-bw-percentage)
                      |           +--rw backup-bandwidth-percent?
                      |                   rt-types:percentage
                      +--rw flow-agg-selector
                      |  +--rw mpls
                      |  |  +--rw (fas-type)?
                      |  |     +--:(label)
                      |  |     |  +--rw (specification-type)?
                      |  |     |     +--:(derived)
                      |  |     |     |  +--rw forwarding-label?
                      |  |     |     |          empty
                      |  |     |     +--:(explicit)
                      |  |     |        +--rw label?
                      |  |     |        |       rt-types:mpls-label
                      |  |     |        +--rw label-position?
                      |  |     |        |       identityref
                      |  |     |        +--rw label-position-offset?
                      |  |     |                uint8
                      |  |     +--:(label-ranges)
                      |  |        +--rw label-range* [index]
                      |  |           +--rw index
                      |  |           |       string
                      |  |           +--rw start-label?
                      |  |           |       rt-types:mpls-label
                      |  |           +--rw end-label?
                      |  |           |       rt-types:mpls-label
                      |  |           +--rw label-position?
                      |  |           |       identityref
                      |  |           +--rw label-position-offset?
                      |  |                   uint8
                      |  +--rw ipv4
                      |  |  +--rw destination-prefix*   inet:ipv4-prefix
                      |  +--rw ipv6
                      |  |  +--rw (fas-type)?
                      |  |     +--:(ipv6-destination)
                      |  |     |  +--rw destination-prefix*
                      |  |     |          inet:ipv6-prefix
                      |  |     +--:(ipv6-hbh-eh)
                      |  |        +--rw fas-hbh-eh*           uint32
                      |  +--rw acl-ref*   nrp-policy-acl-ref
                      +--rw phb?                    string








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Authors' Addresses

   Tarek Saad
   Juniper Networks

   Email: tsaad@juniper.net


   Vishnu Pavan Beeram
   Juniper Networks

   Email: vbeeram@juniper.net


   Bin Wen
   Comcast

   Email: Bin_Wen@cable.comcast.com


   Daniele Ceccarelli
   Ericsson

   Email: daniele.ceccarelli@ericsson.com


   Shaofu Peng
   ZTE Corporation

   Email: peng.shaofu@zte.com.cn


   Ran Chen
   ZTE Corporation

   Email: chen.ran@zte.com.cn


   Luis M. Contreras
   Telefonica

   Email: luismiguel.contrerasmurillo@telefonica.com


   Xufeng Liu
   IBM Corporation

   Email: xufeng.liu.ietf@gmail.com



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