Internet-Draft NRPs YANG January 2024
Wu, et al. Expires 6 July 2024 [Page]
Workgroup:
Network Working Group
Internet-Draft:
draft-wdbsp-teas-nrp-yang-04
Published:
Intended Status:
Standards Track
Expires:
Authors:
B. Wu
Huawei Technologies
D. Dhody
Huawei Technologies
V.P. Beeram
Juniper Networks
T. Saad
Cisco Systems
S. Peng
ZTE Corporation

A YANG Data Model for Network Resource Partitions (NRPs)

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 Service Level Objective (SLO) and Service Level Expectation (SLE) characteristics to be created. This document defines a YANG data model for Network Resource Partitions (NRPs). The model can be used, in particular, for the realization of the IETF Network Slice Services in IP/MPLS networks.

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 6 July 2024.

1. Introduction

As specified in Section 7.4 [I-D.ietf-teas-ietf-network-slices], 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). [I-D.ietf-teas-ietf-network-slices] defines a framework for IETF Network Slice Services, which provide connectivity coupled with network resources commitment between a number of Service Demarcation Points (SDPs) over a shared network infrastructure. The IETF Network Slice service is expressed in terms of one or more connectivity constructs, which can be of a connection type (point-to-point (P2P), point-to-multipoint (P2MP), or any-to-any (A2A)) and any combination of these types. One or more connectivity constructs from one or more IETF Network Slices are mapped to an NRP for ensuring Service Level Objective (SLO) and Service Level Expectation (SLE) and network scalability.

This document defines a YANG module of NRPs. An IETF Network Slice Controller (NSC) can use it to manage NRP instances in order to implement Network Slice Services.

An NRP Policy [I-D.ietf-teas-ns-ip-mpls] 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.Section 3.1 describes the detailed definition of NRP policy in NRP instantiation.

According to the YANG model classification of [RFC8309], the NRPs model is a network configuration model.

2. Terminology

The following terms are defined in [RFC6241] and are used in this specification:

  • configuration data

  • state data

The following terms are defined in [RFC7950] and are used in this specification:

  • augment

  • data model

  • data node

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

The tree diagram used in this document follows the notation defined in [RFC8340].

3. NRPs Data Model

There are multiple modes of NRPs operations to be supported as follows:

  • NRPs instantiation: Depending on the slice service types and also network status, there can be two types of approaches. One method is to create an NRP instance before the network controller processes the IETF Network Slice service request. Another one is that the network controller may start creating an NRP instance while configuring the IETF Network Slice service request.

  • NRPs modification: When the capacity of an existing NPR link is close to capacity, the bandwidth of the link could be increased. And when an NRP links or nodes resources are insufficient, new NRP links and nodes could be added.

  • NRPs Deletion: If the NSC determines that no slice service is using an NRP, the NSC can delete the NRP instance.

  • NRPs Monitoring: The NSC can use the NRPs model to track and monitor NRPs resource status and usage.

3.1. NRPs Instantiation

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 partition 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 NRP and to apply the corresponding Per-Hop Behavior (PHB) or forwarding mechanism that determines the forwarding treatment of the packets belonging to the NRP. When catering to IETF Network Slices, this NRP identification is referred to as the NRP selector and may 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 management.

'nrp-policy' is defined to enable NRP Stateful Traffic Engineering (NRP-TE) [I-D.ietf-teas-nrp-scalability][I-D.ietf-teas-ns-ip-mpls] and/or NRP IGP forwarding in IP/MPLS networks.

The high-level model structure of NRP policy defined by this document is as shown in Figure 1:

module: ietf-nrp
  augment /nw:networks:
    +--rw nrp-policies
       +--rw nrp-policy* [name]
          +--rw name                    string
          +--rw nrp-id?                 uint32
          +--rw mode?                   identityref
          +--rw resource-reservation
          |     ...
          +--rw selector
          |     ...
          +--rw phb-profile?            string
          +--rw topology
                ...
Figure 1: NRP Policy subtree high-level structure

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.

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 an NRP. Each entry also carries an 'nrp-id' leaf which uniquely identifies the NRP created by the enforcement of this policy.

The description of the 'nrp-policies' data nodes are as follows, and the other key elements of each nrp-policy entry are discussed in the following sub-sections.

  • 'nrp-id': Is an identifier that is used to uniquely identify an NRP instance within an NSC network scope.

  • 'mode': Refers to control plane resource partition, data plane resource partition, or a combination of both types.

3.1.1. Resource Reservation

The 'resource-reservation' container specifies the bandwidth resource allocated to an NRP instance, or can be overridden by the configuration of the link specific 'resource-reservation' nodes of 'nrp-topology'.

+--rw resource-reservation
  +--rw (max-bw-type)?
     +--:(bw-value)
     |  +--rw maximum-bandwidth?           uint64
     +--:(bw-percentage)
        +--rw maximum-bandwidth-percent?   rt-types:percentage
Figure 2: NRP Resource Reservation YANG subtree structure

3.1.2. NRP Selector

NRP selector defines the data plane encapsulation types and values that are used to identify NRP-specific network resources.

[I-D.ietf-teas-nrp-scalability] discusses several candidate NRP selector encapsulation schemes, including IP, MPLS, or SRv6, for example, the IPv6 Hop-by-Hop extension header defined in [I-D.ietf-6man-enhanced-vpn-vtn-id], or the SRv6 SID defined in [I-D.ietf-spring-sr-for-enhanced-vpn]. Since the MPLS encapsulation schemes are still under discussion, the model only provides a place holder for future updates. Additionally, the use of NRP-specific IP addresses to identify NRP resources, or the use of specific ACLs, are optional NRP selector mechanisms.

+--rw selector
|  +--rw ipv4
|  |  +--rw destination-prefix*   inet:ipv4-prefix
|  +--rw ipv6
|  |  +--rw (selector-type)?
|  |     +--:(dedicated)
|  |     |  +--rw ipv6-hbh-eh?          uint32
|  |     +--:(srv6-sid-derived)
|  |     |  +--rw srv6-sid*             inet:ipv6-prefix
|  |     +--:(ipv6-destination-derived)
|  |        +--rw destination-prefix*   inet:ipv6-prefix
|  +--rw mpls
|  +--rw acl-ref*   nrp-acl-ref
Figure 3: NRP Selector YANG subtree structure

3.1.3. Per-Hop Behavior (PHB)

PHB and NRP selector are combined mechanisms. PHB is used to specify the forwarding treatment of packets belonging to a specific NRP selector, such as bandwidth control, congestion control (e.g., Section 3.4 [RFC3644]). The exact definition of PHB is locally defined by the device or controller managing the NRPs. The 'phb-profile' leaf carries a name of a PHB profile available on the topological element where the policy is being enforced. Some examples of "phb-probile" may be standard PHBs, such as "Assured Forwarding (AF)", "Expedited Forwarding (EF)", or a customized local policies, such as "High", "Low", "Standard".

+--rw phb-profile?            string
Figure 4: PHB YANG subtree structure

3.1.4. NRP Topology

'nrp-topology' defines a dedicated NRP topology.

When an NRP support IGP forwarding, the topology of the NRP must be congruent with an IGP instance.The topology used for IGP route computation and forwarding can be derived using Multi-Topology Routing (MTR) or Flex-algo. Multi-Topology Routing (MTR) is defined in [RFC4915], [RFC5120], and [I-D.ietf-lsr-isis-sr-vtn-mt] or Flex-algo is defined in [RFC9350].

Figure 5 shows an example of NRP-1 enabling "igp-congruent", which indicates that this NRP instance uses the same IGP topology with the specified 'multi-topology-id' or 'algo-id'. As illustrated, NRP-1 has different link resource attributes from those of the IGP, but shares the same the nodes and termination point (TPs) of the IGP topology.

                          # O #### O #### O
                        #  #      #      #
                       O   #      #      #
                        #  #      #      #
                         # O #### O #### O
                                 NRP-1

                                  ||
                                  vv
                            O-----O-----O
                          / |     |     |
                         O  |     |     |
                          \ |     |     |
                            O-----O-----O
                        IGP Topology (MT or Flex-algo)
     Legend

     O     Virtual node
     ---   IGP links
     ###   Virtual links with a set of reserved resources
Figure 5: IGP Congruency Example

The 'selection' container consists of a list of select subset of links of an underlay topology or a pre-built topology.

The 'filter' container consists of a list of filters where each entry references a topology filter [I-D.bestbar-teas-yang-topology-filter]. The topological elements that satisfy the membership criteria can optionally override the default resource-reservation and nrp-selector specific leafs.

+--rw topology
   +--rw igp-congruent!
   |  +--rw multi-topology-id?   uint32
   |  +--rw algo-id?             uint32
   |  +--rw sharing?             boolean
   +--rw (topology-type)?
      +--:(selection)
      |  +--rw select
      |     +--rw topology-group* [group-id]
      |        +--rw group-id                string
      |        +--rw base-topology-ref
      |        |     ...
      |        +--rw links* [link-ref]
      |        |     ...
      |        +--rw resource-reservation
      |        |     ...
      |        +--rw link-partition-type?
      |        |       identityref
      |        +--rw phb-profile?            string
      +--:(filter)
         +--rw filters
            +--rw filter* [filter-ref]
               +--rw filter-ref
               |       nrp-topo-filter-ref
               +--rw resource-reservation
               |     ...
               +--rw selector
               |     ...
               +--rw phb-profile?            string
Figure 6: NRP Topology YANG subtree structure

3.2. NRPs monitoring

The NRPs model can be used to track and monitor operational status and resource usage of NRPs.

  augment /nw:networks/nw:network/nw:network-types:
    +--rw nrp!
  augment /nw:networks/nw:network/nw:node:
    +--ro nrp
       +--ro nrp-aware-dp-id
             ...
  augment /nw:networks/nw:network/nt:link:
    +--ro nrp
       +--ro link-partition-type?   identityref
       +--ro bandwidth-value?       uint64
       +--ro nrp-aware-dp-id
       |     ...
       +--ro statistics
             ...
  augment /nw:networks/nw:network/nw:node:
    +--ro nrps* [nrp-id]
       +--ro nrp-id    uint32
       +--ro nrp
             ...
  augment /nw:networks/nw:network/nt:link:
    +--ro nrps* [nrp-id]
       +--ro nrp-id                 uint32
       +--ro link-partition-type?   identityref
       +--ro bandwidth-value?       uint64
       +--ro nrp-aware-dp-id
             ...
Figure 7: NRPs Monitoring YANG subtree structure

3.3. NRPs Device Model Description

The device-specific NRPs model is defined in module 'ietf-nrp-device' as shown in Figure 10, which augments NRPs YANG data model in Figure 9 and adds interface attributes, including resource reservation, NRP selector, and PHB profile, that are specific to an NRP device.

Figure below shows the tree diagram of the device NRPs YANG model defined in modules 'ietf-nrp-device.yang'.

module: ietf-nrp-device
  augment /nw:networks/nrp:nrp-policies/nrp:nrp-policy:
    +--rw interfaces
       +--rw interface* [interface]
          +--rw interface               if:interface-ref
          +--rw resource-reservation
          |  +--rw (max-bw-type)?
          |     +--:(bw-value)
          |     |     ...
          |     +--:(bw-percentage)
          |           ...
          +--rw selector
          |  +--rw ipv4
          |  |  +--rw destination-prefix*   inet:ipv4-prefix
          |  +--rw ipv6
          |  |  +--rw (selector-type)?
          |  |        ...
          |  +--rw mpls
          |  |  +--rw (selector-type)?
          |  |        ...
          |  +--rw acl-ref*   nrp-acl-ref
          +--rw phb-profile?            string
Figure 8: NRPs Device YANG subtree high-level structure

4. NRPs Yang Module

The 'ietf-nrp' module uses types defined in [RFC8345], [RFC8294],[RFC8776], [RFC6991], [RFC8519], [I-D.ietf-spring-srv6-yang], and [I-D.bestbar-teas-yang-topology-filter].

<CODE BEGINS> file "ietf-nrp@2024-01-03.yang"

module ietf-nrp {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-nrp";
  prefix nrp;

  import ietf-network {
    prefix nw;
    reference
      "RFC 8345: A YANG Data Model for Network Topologies";
  }
  import ietf-network-topology {
    prefix nt;
    reference
      "RFC 8345: A YANG Data Model for Network Topologies";
  }
  import ietf-routing-types {
    prefix rt-types;
    reference
      "RFC 8294: Common YANG Data Types for the Routing Area";
  }
  import ietf-te-types {
    prefix te-types;
    reference
      "RFC 8776: Traffic Engineering Common YANG Types";
  }
  import ietf-te-packet-types {
    prefix te-packet-types;
    reference
      "RFC 8776: Traffic Engineering Common YANG Types";
  }
  import ietf-inet-types {
    prefix inet;
    reference
      "RFC 6991: Common YANG Data Types";
  }
  import ietf-access-control-list {
    prefix acl;
    reference
      "RFC 8519: YANG Data Model for Network Access Control Lists
       (ACLs)";
  }
  import ietf-srv6-types {
    prefix srv6-types;
    reference
      "draft-ietf-spring-srv6-yang: YANG Data Model for SRv6 Base
       and Static";
  }
  import ietf-topology-filter {
    prefix topo-filt;
    reference
      "draft-bestbar-teas-yang-topology-filter: YANG Data Model
       for Topology Filter";
  }

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

     Editor:   Bo Wu
            <mailto:lana.wubo@huawei.com>
     Editor:   Dhruv Dhody
            <mailto:dhruv.ietf@gmail.com>

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

     Editor:   Tarek Saad
               <mailto:tsaad.net@gmail.com>

     Editor:   Shaofu Peng
               <mailto:peng.shaofu@zte.com.cn>";
  description
    "This YANG module defines a data model for
     Network Resource Partitions (NRPs) managment.

     Copyright (c) 2024 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject
     to the license terms contained in, the Revised BSD License
     set forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX
     (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
     for full legal notices.";

  revision 2024-01-03 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A YANG Data Model for Network Resource
       Partitions (NRPs)";
  }

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

  identity nrp-partition-mode {
    description
      "Base identity for NRP partition type.";
  }

  identity nrp-control-plane-partition {
    base nrp-partition-mode;
    description
      "Identity for NRP control plane partition.";
  }

  identity nrp-data-plane-partition {
    base nrp-partition-mode;
    description
      "Identity for NRP data plane partition.";
  }

  identity nrp-hybrid-plane-partition {
    base nrp-partition-mode;
    description
      "Identity for both control and data planes partitions of NRP.";
  }

  identity nrp-link-partition-type {
    description
      "Base identity for NRP interface partition type.";
  }

  identity virtual-sub-interface-partition {
    base nrp-link-partition-type;
    description
      "Identity for NRP virtual interface or sub-interface partition,
       e.g. FlexE.";
  }

  identity queue-partition {
    base nrp-link-partition-type;
    description
      "Identity for NRP queue partition type.";
  }

  /*
   * T Y P E D E F S
   */

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

  typedef nrp-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.";
    reference
      "draft-bestbar-teas-yang-topology-filter: YANG Data Model
       for Topology Filter";
  }

  /*
   * Grouping - NRP Resource Reservation
   */

  grouping nrp-resource-reservation {
    description
      "Grouping for NRP resource reservation.";
    container resource-reservation {
      description
        "Container for NRP resource reservation.";
      choice max-bw-type {
        description
          "Choice of maximum bandwidth specification.";
        case bw-value {
          leaf maximum-bandwidth {
            type uint64;
            units "bits/second";
            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.";
          }
        }
      }
    }
  }

  /*
   * Grouping - NRP Selector Configuration
   */

  grouping nrp-selector-config {
    description
      "Grouping for NRP selector configuration.";
    container selector {
      description
        "Container for NRP selector.";
      container ipv4 {
        description
          "Container for IPv4 NRP selector.";
        leaf-list destination-prefix {
          type inet:ipv4-prefix;
          description
            "Any prefix from the specified set of IPv4
             destination prefixes can be the selector.";
        }
      }
      container ipv6 {
        description
          "Container for IPv6 NRP selector.";
        choice selector-type {
          description
            "Choices for IPv6 selector type.";
          case dedicated {
            leaf ipv6-hbh-eh {
              type uint32;
              description
                "The selector value carried in Hop-by-Hop
                 Option of IPv6 extension header.";
              reference
                "draft-ietf-6man-enhanced-vpn-vtn-id: Carrying Virtual
                 Transport Network (VTN) Information in IPv6 Extension
                 Header";
            }
          }
          case srv6-sid-derived {
            leaf-list srv6-sid {
              type srv6-types:srv6-sid;
              description
                "Any SID from the specified set of SRv6 SID can
                 be the selector.";
              reference
                "draft-ietf-spring-sr-for-enhanced-vpn: Segment
                 Routing based Virtual Transport Network (VTN) for
                 Enhanced VPN";
            }
          }
          case ipv6-destination-derived {
            leaf-list destination-prefix {
              type inet:ipv6-prefix;
              description
                "Any prefix from the specified set of IPv6
                 destination prefixes can be the selector.";
            }
          }
        }
      }
      container mpls {
        description
          "Container for MPLS NRP selector. This is a placeholder
           for future updates based on the MPLS solutions.";
      }
      leaf-list acl-ref {
        type nrp-acl-ref;
        description
          "Selection is done based on the specified list of ACLs.";
        reference
          "RFC 8519: YANG Data Model for Network Access Control Lists
           (ACLs)";
      }
    }
  }

  /*
   * Grouping - NRP QoS PHB profile
   */

  grouping nrp-qos-phb-profile {
    description
      "Grouping for NRP QoS PHB profile.";
    leaf phb-profile {
      type string;
      description
        "PHB profile identifier, specifying the forwarding treatment
         of packets belonging to a specific NRP selector, such as
         bandwidth control, congestion control
         (e.g., Section 3.4 [RFC3644]).  The PHB may be standard PHB,
         such as Assured Forwarding (AF), Expedited Forwarding (EF),
         or a customized local policy, such as 'High', 'Low',
         'Standard'.";
    }
  }

  /*
   * Grouping - NRP IGP congruent
   */

  grouping nrp-igp-congruent {
    description
      "Grouping for NRP IGP congruent attributes.";
    container igp-congruent {
      presence "Indicates NRP IGP congruency.";
      description
        "The presence of the container node describes NRP IGP
         congruent, which indicates that the NRP instance uses the same
         IGP topology with the specified 'multi-topology-id'
         and 'algo-id'. That is, the nodes and termination point of the
         NRP topology and the IGP topology are the same, while the link
         attributes of the NRP are different from those of the IGP.";
      leaf multi-topology-id {
        type uint32;
        description
          "Indicates the MT-id of the NRP IGP instance.";
        reference
          "RFC 5120:  M-ISIS: Multi Topology (MT) Routing in
           Intermediate System to Intermediate Systems (IS-ISs)
           RFC 4915:  Multi-Topology (MT) Routing in OSPF";
      }
      leaf algo-id {
        type uint32;
        description
          "Indicates the algo-id of the NRP IGP instance.";
        reference
          "RFC 9350: IGP Flexible Algorithm";
      }
      leaf sharing {
        type boolean;
        default "true";
        description
          "'true' if the the NRP IGP instance can be shared with
           other NRPs;
           'false' if the the NRP IGP instance is dedicated
           to this NRP.";
      }
    }
  }

  /*
   * Grouping - NRP Topology Filter
   */

  grouping nrp-topology-filter {
    description
      "Grouping for NRP filter topology.";
    container filters {
      description
        "Container for filters.";
      list filter {
        key "filter-ref";
        description
          "List of filters.";
        leaf filter-ref {
          type nrp-topo-filter-ref;
          description
            "Reference to a specific topology filter from the
             list of global topology filters.";
        }
        uses nrp-resource-reservation;
        uses nrp-selector-config;
        uses nrp-qos-phb-profile;
      }
    }
  }

  /*
   * Grouping - NRP Select Topology
   */

  grouping nrp-select-topology {
    description
      "NRP topology specified by selection.";
    container select {
      description
        "The container of NRP select topology.";
      list topology-group {
        key "group-id";
        description
          "List of groups for NRP topology elements (node or links)
           that share common attributes.";
        leaf group-id {
          type string;
          description
            "The NRP topology group identifier.";
        }
        container base-topology-ref {
          description
            "Container for the base topology reference.";
          uses nw:network-ref;
        }
        list links {
          key "link-ref";
          description
            "A list of links with common attributes";
          leaf link-ref {
            type leafref {
              path
                "/nw:networks/nw:network[nw:network-id=current()"
              + "/../../base-topology-ref/network-ref]"
              + "/nt:link/nt:link-id";
            }
            description
              "A reference to a link in the base topology.";
          }
        }
        uses nrp-resource-reservation;
        leaf link-partition-type {
          type identityref {
            base nrp-link-partition-type;
          }
          description
            "Indicates the resource reservation type of an NRP link.";
        }
        uses nrp-qos-phb-profile;
      }
    }
  }

  /*
   * Grouping - NRP Topology
   */

  grouping nrp-topology {
    description
      "Grouping for NRP topology.";
    container topology {
      description
        "Container for NRP topology.";
      uses nrp-igp-congruent;
      choice topology-type {
        description
          "Choice of NRP topology type.";
        case selection {
          uses nrp-select-topology;
        }
        case filter {
          uses nrp-topology-filter;
        }
      }
    }
  }

  /*
   * Grouping - NRP Policy
   */

  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.";
        }
        leaf mode {
          type identityref {
            base nrp-partition-mode;
          }
          default "nrp-hybrid-plane-partition";
          description
            "Indicates the resource partition mode of the NRP, such as
             control plane partition, data plane partition,
             or hybrid partition.";
        }
        uses nrp-resource-reservation;
        uses nrp-selector-config;
        uses nrp-qos-phb-profile;
        uses nrp-topology;
      }
    }
  }

  /*
   * Grouping - NRP Selector State
   */

  grouping nrp-selector-state {
    description
      "The grouping of NRP selector.";
    container selector {
      config false;
      description
        "The container of NRP selector.";
      leaf srv6 {
        type srv6-types:srv6-sid;
        description
          "Indicates the SRv6 SID value as the NRP selector.";
      }
    }
  }

  /*
   * Grouping - NRP node attributes
   */

  grouping nrp-node-attributes {
    description
      "NRP node scope attributes.";
    container nrp {
      config false;
      description
        "Containing NRP attributes.";
      uses nrp-selector-state;
    }
  }

  /*
   * Grouping - NRP Link Attributes
   */

  grouping nrp-link-attributes {
    description
      "NRP link scope attributes.";
    leaf link-partition-type {
      type identityref {
        base nrp-link-partition-type;
      }
      config false;
      description
        "Indicates the resource partition type of an NRP link.";
    }
    leaf bandwidth-value {
      type uint64;
      units "bits/second";
      config false;
      description
        "Bandwidth allocation for the NRP as absolute value.";
    }
    uses nrp-selector-state;
  }

  /*
   * Grouping - NRP Bandwidth Metrics
   */

  grouping nrp-bandwidth-metrics {
    description
      "Grouping for NRP bandwidth metrics.";
    leaf one-way-available-bandwidth {
      type uint64;
      units "bits/second";
      description
        "Available bandwidth that is defined to be NRP link
         bandwidth minus bandwidth utilization..";
    }
    leaf one-way-utilized-bandwidth {
      type uint64;
      units "bits/second";
      description
        "Bandwidth utilization that represents the actual
         utilization of the link (i.e. as measured in the router).";
    }
  }

  // nrp-link-statistics

  grouping nrp-statistics-per-link {
    description
      "Statistics attributes per NRP link.";
    container statistics {
      config false;
      description
        "Statistics for NRP link.";
      leaf admin-status {
        type te-types:te-admin-status;
        description
          "The administrative state of the link.";
      }
      leaf oper-status {
        type te-types:te-oper-status;
        description
          "The current operational state of the link.";
      }
      uses nrp-bandwidth-metrics;
      uses te-packet-types:one-way-performance-metrics-packet;
    }
  }

  // nrp-network-type

  grouping nrp-network-type {
    description
      "Identifies the network type to be NRP.";
    container nrp {
      presence "Indicates NRP network topology.";
      description
        "The presence of the container node indicates NRP network.";
    }
  }

  /*
   * Augment - Network Resource Partition Policies.
   */

  augment "/nw:networks" {
    description
      "Augment networks with NRP policies.";
    uses nrp-pol;
  }

  /*
   * Augment - NRP type.
   */

  augment "/nw:networks/nw:network/nw:network-types" {
    description
      "Indicates the network type of NRP";
    uses nrp-network-type;
  }

  /*
   * Augment - NRP node operational status.
   */

  augment "/nw:networks/nw:network/nw:node" {
    when '../nw:network-types/nrp:nrp' {
      description
        "Augment only for NRP network topology.";
    }
    description
      "Augment node configuration and state.";
    uses nrp-node-attributes;
  }

  /*
   * Augment - NRP link operational status.
   */

  augment "/nw:networks/nw:network/nt:link" {
    when '../nw:network-types/nrp:nrp' {
      description
        "Augment only for NRP network topology.";
    }
    description
      "Augment link configuration and state.";
    container nrp {
      config false;
      description
        "Containing NRP attributes.";
      uses nrp-link-attributes;
      uses nrp-statistics-per-link;
    }
  }

  /*
   * Augment - Native topology with NRPs node operational status.
   */

  augment "/nw:networks/nw:network/nw:node" {
    description
      "Augment node with NRPs aware attributes.";
    list nrps {
      key "nrp-id";
      config false;
      description
        "List of NRPs.";
      leaf nrp-id {
        type uint32;
        description
          "NRP identifier";
      }
      uses nrp-node-attributes;
    }
  }

  /*
   * Augment - Native topology with NRPs link operational status.
   */

  augment "/nw:networks/nw:network/nt:link" {
    description
      "Augment link with NRPs aware attributes.";
    list nrps {
      key "nrp-id";
      config false;
      description
        "List of NRPs.";
      leaf nrp-id {
        type uint32;
        description
          "NRP identifier";
      }
      uses nrp-link-attributes;
    }
  }
}


<CODE ENDS>
Figure 9: NRPs data model YANG module

5. NRPs Device YANG module

The device NRPs YANG module ('ietf-nrp-device') models augments the NRPs YANG module ('ietf-nrp') and adds the attributes of NRP interfaces that are local to an NRP device.

The device NRPs YANG module imports the following module(s): ietf-interfaces defined in [RFC8343], ietf-network defined in [RFC8345], and grouping defined in this document.

<CODE BEGINS> file "ietf-nrp-device@2024-01-03.yang"

module ietf-nrp-device {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-nrp-device";
  prefix nrp-dev;

  /* Import IETF Network module */

  import ietf-network {
    prefix nw;
    reference
      "RFC 8345: RFC 8345: A YANG Data Model for Network Topologies";
  }

  /* Import IETF interface module */

  import ietf-interfaces {
    prefix if;
    reference
      "RFC8343: A YANG Data Model for Interface Management";
  }

  /* Import NRPs module */

  import ietf-nrp {
    prefix nrp;
    reference
      "RFCXXXX: A YANG Data Model for Network Resource
       Partitions (NRPs)";
  }

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

     Editor:   Bo Wu
            <mailto:lana.wubo@huawei.com>

     Editor:   Dhruv Dhody
            <mailto:dhruv.ietf@gmail.com>

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

     Editor:   Tarek Saad
               <mailto:tsaad.net@gmail.com>

     Editor:   Shaofu Peng
               <mailto:peng.shaofu@zte.com.cn>";
  description
    "This YANG module defines a data model for Network Resource
     Partitions (NRPs) device configurations and states. The model
     fully conforms to the Network Management Datastore
     Architecture (NMDA).

     Copyright (c) 2024 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

     Redistribution and use in source and binary forms, with or
     without modification, is permitted pursuant to, and subject to
     the license terms contained in, the Revised BSD License set
     forth in Section 4.c of the IETF Trust's Legal Provisions
     Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX
     (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself
     for full legal notices.";

  // RFC Ed.: replace XXXX with actual RFC number and remove this
  // note.
  // RFC Ed.: update the date below with the date of RFC publication
  // and remove this note.

  revision 2024-01-03 {
    description
      "Initial revision.";
    reference
      "RFCXXXX: A YANG Data Model for Network Resource Partitions (NRPs)
       Device";
  }

  /* NRP device configuraiton */

  augment "/nw:networks/nrp:nrp-policies/nrp:nrp-policy" {
    description
      "NRP policy list.";
    /* NRP Interface Configuration Data */
    container interfaces {
      description
        "Configuration data model for NRP interfaces.";
      list interface {
        key "interface";
        description
          "NRP interfaces.";
        leaf interface {
          type if:interface-ref;
          description
            "NRP interface name.";
        }
        uses nrp:nrp-resource-reservation;
        uses nrp:nrp-selector-config;
        uses nrp:nrp-qos-phb-profile;
      }
    }
  }
}

<CODE ENDS>
Figure 10: NRPs Device data model YANG module

6. Security Considerations

The YANG model defined in this document 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 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.

There are a number of data nodes defined in this YANG model 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.

nrp-link: A malicious client could attempt to remove a link from a topology, add a new link. In each case, the structure of the topology would be sabotaged, and this scenario could, for example, result in an NRP topology that is less than optimal.

The entries in the nodes above include the whole network configurations corresponding with the NRP, and indirectly create or modify the PE or P device configurations. Unexpected changes to these entries could lead to service disruption and/or network misbehavior.

7. IANA Considerations

This document registers a 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
   Registrant Contact: The IESG.
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:ietf-nrp-device
   Registrant Contact: The IESG.
   XML: N/A, the requested URI is an XML namespace.

This document requests to register a YANG module in the YANG Module Names registry [RFC7950].

           Name: ietf-nrp
           Namespace: urn:ietf:params:xml:ns:yang:ietf-nrp
           Maintained by IANA: N
           Prefix: nrp
           Reference: RFC XXXX

           Name: ietf-nrp-device
           Namespace: urn:ietf:params:xml:ns:yang:ietf-nrp-device
           Maintained by IANA: N
           Prefix: nrp-dev
           Reference: RFC XXXX

8. Acknowledgments

The authors would like to thank Krzysztof Szarkowicz, Jie Dong, Qin Wu, Yao Zhao, Zhenbing Li, Ying Cheng, Liyan Gong, and many others for their helpful comments and suggestions.

9. Contributor

The following individuals, authors of [I-D.bestbar-teas-yang-nrp-policy] and [I-D.wd-teas-nrp-yang], contributed to this consolidated document:

   Xufeng Liu
   IBM Corporation
   Email: xufeng.liu.ietf@gmail.com

   Mohamed Boucadair
   Orange
   Email: mohamed.boucadair@orange.com

   Daniele Ceccarelli

   Bin Wen
   Comcast
   Email: Bin_Wen@cable.comcast.com

   Ran Chen
   ZTE Corporation
   Email: chen.ran@zte.com.cn

   Luis M. Contreras
   Telefonica
   Email: luismiguel.contrerasmurillo@telefonica.com

   Ying Cheng
   China Unicom
   Email: chengying10@chinaunicom.cn

   Liyan Gong
   China Mobile
   Email: gongliyan@chinamobile.com

10. References

10.1. Normative References

[I-D.bestbar-teas-yang-topology-filter]
Beeram, V. P., Saad, T., Gandhi, R., and X. Liu, "YANG Data Model for Topology Filter", Work in Progress, Internet-Draft, draft-bestbar-teas-yang-topology-filter-04, , <https://datatracker.ietf.org/doc/html/draft-bestbar-teas-yang-topology-filter-04>.
[I-D.ietf-6man-enhanced-vpn-vtn-id]
Dong, J., Li, Z., Xie, C., Ma, C., and G. S. Mishra, "Carrying Virtual Transport Network (VTN) Information in IPv6 Extension Header", Work in Progress, Internet-Draft, draft-ietf-6man-enhanced-vpn-vtn-id-05, , <https://datatracker.ietf.org/doc/html/draft-ietf-6man-enhanced-vpn-vtn-id-05>.
[I-D.ietf-spring-srv6-yang]
Raza, S., Agarwal, S., Liu, X., Hu, Z., Hussain, I., Shah, H. C., Voyer, D., Matsushima, S., Horiba, K., Rajamanickam, J., and A. Abdelsalam, "YANG Data Model for SRv6 Base and Static", Work in Progress, Internet-Draft, draft-ietf-spring-srv6-yang-02, , <https://datatracker.ietf.org/doc/html/draft-ietf-spring-srv6-yang-02>.
[RFC3688]
Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, , <https://www.rfc-editor.org/info/rfc3688>.
[RFC4915]
Psenak, P., Mirtorabi, S., Roy, A., Nguyen, L., and P. Pillay-Esnault, "Multi-Topology (MT) Routing in OSPF", RFC 4915, DOI 10.17487/RFC4915, , <https://www.rfc-editor.org/info/rfc4915>.
[RFC5120]
Przygienda, T., Shen, N., and N. Sheth, "M-ISIS: Multi Topology (MT) Routing in Intermediate System to Intermediate Systems (IS-ISs)", RFC 5120, DOI 10.17487/RFC5120, , <https://www.rfc-editor.org/info/rfc5120>.
[RFC6241]
Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, , <https://www.rfc-editor.org/info/rfc6241>.
[RFC6242]
Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, , <https://www.rfc-editor.org/info/rfc6242>.
[RFC6991]
Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, , <https://www.rfc-editor.org/info/rfc6991>.
[RFC7950]
Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, , <https://www.rfc-editor.org/info/rfc7950>.
[RFC7951]
Lhotka, L., "JSON Encoding of Data Modeled with YANG", RFC 7951, DOI 10.17487/RFC7951, , <https://www.rfc-editor.org/info/rfc7951>.
[RFC8040]
Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, , <https://www.rfc-editor.org/info/rfc8040>.
[RFC8294]
Liu, X., Qu, Y., Lindem, A., Hopps, C., and L. Berger, "Common YANG Data Types for the Routing Area", RFC 8294, DOI 10.17487/RFC8294, , <https://www.rfc-editor.org/info/rfc8294>.
[RFC8340]
Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, , <https://www.rfc-editor.org/info/rfc8340>.
[RFC8341]
Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, , <https://www.rfc-editor.org/info/rfc8341>.
[RFC8343]
Bjorklund, M., "A YANG Data Model for Interface Management", RFC 8343, DOI 10.17487/RFC8343, , <https://www.rfc-editor.org/info/rfc8343>.
[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, , <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, , <https://www.rfc-editor.org/info/rfc8446>.
[RFC8519]
Jethanandani, M., Agarwal, S., Huang, L., and D. Blair, "YANG Data Model for Network Access Control Lists (ACLs)", RFC 8519, DOI 10.17487/RFC8519, , <https://www.rfc-editor.org/info/rfc8519>.
[RFC8776]
Saad, T., Gandhi, R., Liu, X., Beeram, V., and I. Bryskin, "Common YANG Data Types for Traffic Engineering", RFC 8776, DOI 10.17487/RFC8776, , <https://www.rfc-editor.org/info/rfc8776>.

10.2. Informative References

[I-D.bestbar-teas-yang-nrp-policy]
Beeram, V. P., Saad, T., Wen, B., Ceccarelli, D., Peng, S., Chen, R., Contreras, L. M., and X. Liu, "YANG Data Model for Network Resource Partition Policy", Work in Progress, Internet-Draft, draft-bestbar-teas-yang-nrp-policy-03, , <https://datatracker.ietf.org/doc/html/draft-bestbar-teas-yang-nrp-policy-03>.
[I-D.ietf-lsr-isis-sr-vtn-mt]
Xie, C., Ma, C., Dong, J., and Z. Li, "Applicability of IS-IS Multi-Topology (MT) for Segment Routing based Network Resource Partition (NRP)", Work in Progress, Internet-Draft, draft-ietf-lsr-isis-sr-vtn-mt-06, , <https://datatracker.ietf.org/doc/html/draft-ietf-lsr-isis-sr-vtn-mt-06>.
[I-D.ietf-spring-sr-for-enhanced-vpn]
Dong, J., Miyasaka, T., Zhu, Y., Qin, F., and Z. Li, "Segment Routing based Virtual Transport Network (VTN) for Enhanced VPN", Work in Progress, Internet-Draft, draft-ietf-spring-sr-for-enhanced-vpn-06, , <https://datatracker.ietf.org/doc/html/draft-ietf-spring-sr-for-enhanced-vpn-06>.
[I-D.ietf-teas-ietf-network-slices]
Farrel, A., Drake, J., Rokui, R., Homma, S., Makhijani, K., Contreras, L. M., and J. Tantsura, "A Framework for Network Slices in Networks Built from IETF Technologies", Work in Progress, Internet-Draft, draft-ietf-teas-ietf-network-slices-25, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-ietf-network-slices-25>.
[I-D.ietf-teas-nrp-scalability]
Dong, J., Li, Z., Gong, L., Yang, G., Mishra, G. S., and F. Qin, "Scalability Considerations for Network Resource Partition", Work in Progress, Internet-Draft, draft-ietf-teas-nrp-scalability-03, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-nrp-scalability-03>.
[I-D.ietf-teas-ns-ip-mpls]
Saad, T., Beeram, V. P., Dong, J., Wen, B., Ceccarelli, D., Halpern, J. M., Peng, S., Chen, R., Liu, X., Contreras, L. M., Rokui, R., and L. Jalil, "Realizing Network Slices in IP/MPLS Networks", Work in Progress, Internet-Draft, draft-ietf-teas-ns-ip-mpls-03, , <https://datatracker.ietf.org/doc/html/draft-ietf-teas-ns-ip-mpls-03>.
[I-D.wd-teas-nrp-yang]
Wu, B., Dhody, D., Boucadair, M., Cheng, Y., and L. Gong, "A YANG Data Model for Network Resource Partitions (NRPs)", Work in Progress, Internet-Draft, draft-wd-teas-nrp-yang-02, , <https://datatracker.ietf.org/doc/html/draft-wd-teas-nrp-yang-02>.
[RFC3644]
Snir, Y., Ramberg, Y., Strassner, J., Cohen, R., and B. Moore, "Policy Quality of Service (QoS) Information Model", RFC 3644, DOI 10.17487/RFC3644, , <https://www.rfc-editor.org/info/rfc3644>.
[RFC8309]
Wu, Q., Liu, W., and A. Farrel, "Service Models Explained", RFC 8309, DOI 10.17487/RFC8309, , <https://www.rfc-editor.org/info/rfc8309>.
[RFC9350]
Psenak, P., Ed., Hegde, S., Filsfils, C., Talaulikar, K., and A. Gulko, "IGP Flexible Algorithm", RFC 9350, DOI 10.17487/RFC9350, , <https://www.rfc-editor.org/info/rfc9350>.

Appendix A. An Example

This section contains an example of an instance data tree in JSON encoding [RFC7951]. The example below instantiates an NRP for the topology that is depicted in the following diagram. There are three nodes, D1, D2, and D3. D1 has three termination points, 1-0-1, 1-2-1, and 1-3-1. D2 has three termination points as well, 2-1-1, 2-0-1, and 2-3-1. D3 has two termination points, 3-1-1 and 3-2-1. In addition there are six links, two between each pair of nodes with one going in each direction.



             +------------+                   +------------+
             |     D1     |                   |     D2     |
            /-\          /-\                 /-\          /-\
            | | 1-0-1    | |---------------->| | 2-1-1    | |
            | |    1-2-1 | |<----------------| |    2-0-1 | |
            \-/  1-3-1   \-/                 \-/  2-3-1   \-/
             |   /----\   |                   |   /----\   |
             +---|    |---+                   +---|    |---+
                 \----/                           \----/
                  |  |                             |  |
                  |  |                             |  |
                  |  |                             |  |
                  |  |       +------------+        |  |
                  |  |       |     D3     |        |  |
                  |  |      /-\          /-\       |  |
                  |  +----->| | 3-1-1    | |-------+  |
                  +---------| |    3-2-1 | |<---------+
                            \-/          \-/
                             |            |
                             +------------+
Figure 11: An NRP Instance Example

An corresponding IGP congruent NRP instance data tree is depicted below:

{
  "ietf-network:networks": {
    "nrp-policies": {
      "nrp-policy": [
        {
          "name": "NRP1",
          "nrp-id": "foo:nrp-example1",
          "mode": "nrp-hybrid-plane-partition",
          "resource-reservation": {
            "bw-value": "10000"
          },
          "selector": {
            "ipv6": {
              "ipv6-hbh-eh:": "100"
            }
          },
          "phb-profile:": "High",
          "topology": {
            "igp-congruent": {
              "multi-topology-id": "2"
            },
            "select": {
              "topology-group": [
                {
                  "group-id": "access-group",
                  "base-topology-ref": {
                    "network-ref": "native-topology"
                  },
                  "link": [
                    {
                      "link-ref": "D1,1-2-1,D2,2-1-1"
                    },
                    {
                      "link-ref": "D2,2-1-1,D1,1-2-1"
                    },
                    {
                      "link-ref": "D1,1-3-1,D3,3-1-1"
                    },
                    {
                      "link-ref": "D3,3-1-1,D1,1-3-1"
                    },
                    {
                      "link-ref": "D2,2-3-1,D3,3-2-1"
                    },
                    {
                      "link-ref": "D3,3-2-1,D2,2-3-1"
                    }
                  ],
                  "link-partition-type": "virtual-sub-interface-partition"
                }
              ]
            }
          }
        }
      ]
    }
  }
}
Figure 12: Instance data tree

In addition, an exampe of an NRP that supports the control plane partition mode is shown in the following figure.

{
  "ietf-network:networks": {
    "nrp-policies": {
      "nrp-policy": [
        {
          "name": "NRP2",
          "nrp-id": "foo:nrp-example2",
          "mode": "nrp-control-plane-partition",
          "resource-reservation": {
            "bw-value": "10000"
          },
          "phb-profile:": "EF",
          "topology": {
            "filters": {
              "filter": [
                {
                  "filter-ref": "te-topology-filter1"
                }
              ]
            }
          }
        }
      ]
    }
  }
}

Appendix B. NRPs YANG Module Tree

Figure 13 shows the full tree diagram of the NRPs YANG model defined in module 'ietf-nrp.yang'.

module: ietf-nrp
  augment /nw:networks:
    +--rw nrp-policies
       +--rw nrp-policy* [name]
          +--rw name                    string
          +--rw nrp-id?                 uint32
          +--rw mode?                   identityref
          +--rw resource-reservation
          |  +--rw (max-bw-type)?
          |     +--:(bw-value)
          |     |  +--rw maximum-bandwidth?           uint64
          |     +--:(bw-percentage)
          |        +--rw maximum-bandwidth-percent?
          |                rt-types:percentage
          +--rw selector
          |  +--rw ipv4
          |  |  +--rw destination-prefix*   inet:ipv4-prefix
          |  +--rw ipv6
          |  |  +--rw (selector-type)?
          |  |     +--:(dedicated)
          |  |     |  +--rw ipv6-hbh-eh?          uint32
          |  |     +--:(srv6-sid-derived)
          |  |     |  +--rw srv6-sid*
          |  |     |          inet:ipv6-prefix
          |  |     +--:(ipv6-destination-derived)
          |  |        +--rw destination-prefix*
          |  |                inet:ipv6-prefix
          |  +--rw mpls
          |  +--rw acl-ref*   nrp-acl-ref
          +--rw phb-profile?            string
          +--rw topology
             +--rw igp-congruent!
             |  +--rw multi-topology-id?   uint32
             |  +--rw algo-id?             uint32
             |  +--rw sharing?             boolean
             +--rw (topology-type)?
                +--:(selection)
                |  +--rw select
                |     +--rw topology-group* [group-id]
                |        +--rw group-id                string
                |        +--rw base-topology-ref
                |        |  +--rw network-ref?   leafref
                |        +--rw links* [link-ref]
                |        |  +--rw link-ref    leafref
                |        +--rw resource-reservation
                |        |  +--rw (max-bw-type)?
                |        |     +--:(bw-value)
                |        |     |  +--rw maximum-bandwidth?
                |        |     |          uint64
                |        |     +--:(bw-percentage)
                |        |        +--rw maximum-bandwidth-percent?
                |        |                rt-types:percentage
                |        +--rw link-partition-type?
                |        |       identityref
                |        +--rw phb-profile?            string
                +--:(filter)
                   +--rw filters
                      +--rw filter* [filter-ref]
                         +--rw filter-ref
                         |       nrp-topo-filter-ref
                         +--rw resource-reservation
                         |  +--rw (max-bw-type)?
                         |     +--:(bw-value)
                         |     |  +--rw maximum-bandwidth?
                         |     |          uint64
                         |     +--:(bw-percentage)
                         |        +--rw maximum-bandwidth-percent?
                         |                rt-types:percentage
                         +--rw selector
                         |  +--rw ipv4
                         |  |  +--rw destination-prefix*
                         |  |          inet:ipv4-prefix
                         |  +--rw ipv6
                         |  |  +--rw (selector-type)?
                         |  |     +--:(dedicated)
                         |  |     |  +--rw ipv6-hbh-eh?
                         |  |     |          uint32
                         |  |     +--:(srv6-sid-derived)
                         |  |     |  +--rw srv6-sid*
                         |  |     |          inet:ipv6-prefix
                         |  |     +--:(ipv6-destination-derived)
                         |  |        +--rw destination-prefix*
                         |  |                inet:ipv6-prefix
                         |  +--rw mpls
                         |  +--rw acl-ref*   nrp-acl-ref
                         +--rw phb-profile?            string
  augment /nw:networks/nw:network/nw:network-types:
    +--rw nrp!
  augment /nw:networks/nw:network/nw:node:
    +--ro nrp
       +--ro selector
          +--ro srv6?   srv6-types:srv6-sid
  augment /nw:networks/nw:network/nt:link:
    +--ro nrp
       +--ro link-partition-type?   identityref
       +--ro bandwidth-value?       uint64
       +--ro selector
       |  +--ro srv6?   srv6-types:srv6-sid
       +--ro statistics
          +--ro admin-status?
          |       te-types:te-admin-status
          +--ro oper-status?
          |       te-types:te-oper-status
          +--ro one-way-available-bandwidth?   uint64
          +--ro one-way-utilized-bandwidth?    uint64
          +--ro one-way-min-delay?             uint32
          +--ro one-way-max-delay?             uint32
          +--ro one-way-delay-variation?       uint32
          +--ro one-way-packet-loss?           decimal64
  augment /nw:networks/nw:network/nw:node:
    +--ro nrps* [nrp-id]
       +--ro nrp-id    uint32
       +--ro nrp
          +--ro selector
             +--ro srv6?   srv6-types:srv6-sid
  augment /nw:networks/nw:network/nt:link:
    +--ro nrps* [nrp-id]
       +--ro nrp-id                 uint32
       +--ro link-partition-type?   identityref
       +--ro bandwidth-value?       uint64
       +--ro selector
          +--ro srv6?   srv6-types:srv6-sid
Figure 13

Appendix C. NRPs Device YANG Module Tree

Figure 14 shows the full tree diagram of the NRPs device YANG model defined in module 'ietf-nrp-device.yang'.

module: ietf-nrp-device
  augment /nw:networks/nrp:nrp-policies/nrp:nrp-policy:
    +--rw interfaces
       +--rw interface* [interface]
          +--rw interface               if:interface-ref
          +--rw resource-reservation
          |  +--rw (max-bw-type)?
          |     +--:(bw-value)
          |     |  +--rw maximum-bandwidth?           uint64
          |     +--:(bw-percentage)
          |        +--rw maximum-bandwidth-percent?
          |                rt-types:percentage
          +--rw selector
          |  +--rw ipv4
          |  |  +--rw destination-prefix*   inet:ipv4-prefix
          |  +--rw ipv6
          |  |  +--rw (selector-type)?
          |  |     +--:(dedicated)
          |  |     |  +--rw ipv6-hbh-eh?          uint32
          |  |     +--:(srv6-sid-derived)
          |  |     |  +--rw srv6-sid*
          |  |     |          srv6-types:srv6-sid
          |  |     +--:(ipv6-destination-derived)
          |  |        +--rw destination-prefix*
          |  |                inet:ipv6-prefix
          |  +--rw mpls
          |  +--rw acl-ref*   nrp-acl-ref
          +--rw phb-profile?            string
Figure 14

Authors' Addresses

Bo Wu
Huawei Technologies
101 Software Avenue, Yuhua District
Nanjing
Jiangsu, 210012
China
Dhruv Dhody
Huawei Technologies
Divyashree Techno Park
Bangalore 560066
Karnataka
India
Vishnu Pavan Beeram
Juniper Networks
Tarek Saad
Cisco Systems
Shaofu Peng
ZTE Corporation