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Versions: (draft-aguado-opsawg-l3sm-l3nm) 00 01 02 03 04 05

OPSAWG                                                        S. Barguil
Internet-Draft                                  O. Gonzalez de Dios, Ed.
Intended status: Standards Track                              Telefonica
Expires: April 19, 2021                                M. Boucadair, Ed.
                                                                  Orange
                                                                L. Munoz
                                                                Vodafone
                                                               A. Aguado
                                                                   Nokia
                                                        October 16, 2020


                    A Layer 3 VPN Network YANG Model
                     draft-ietf-opsawg-l3sm-l3nm-05

Abstract

   This document defines a L3VPN Network YANG Model (L3NM) that can be
   used to manage the provisioning of Layer 3 Virtual Private Network
   (VPN) services within a Service Provider's network.  The model
   provides a network-centric view of L3VPN services.

   L3NM is meant to be used by a Network Controller to derive the
   configuration information that will be sent to relevant network
   devices.  The model can also facilitate the communication between a
   service orchestrator and a network controller/orchestrator.

Editorial Note (To be removed by RFC Editor)

   Please update these statements within the document with the RFC
   number to be assigned to this document:

   o  "This version of this YANG module is part of RFC XXXX;"

   o  "RFC XXXX: Layer 3 VPN Network Model";

   o  reference: RFC XXXX

   Also, please update the "revision" date of the YANG module.

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 April 19, 2021.

Copyright Notice

   Copyright (c) 2020 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
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   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
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   4
   3.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . .   4
   4.  L3NM Reference Architecture . . . . . . . . . . . . . . . . .   6
   5.  Relation with other YANG Models . . . . . . . . . . . . . . .   8
   6.  Sample Uses of the L3NM Data Model  . . . . . . . . . . . . .  10
     6.1.  Enterprise Layer 3 VPN Services . . . . . . . . . . . . .  10
     6.2.  Multi-Domain Resource Management  . . . . . . . . . . . .  10
     6.3.  Management of Multicast Services  . . . . . . . . . . . .  11
   7.  Description of the L3NM YANG Module . . . . . . . . . . . . .  11
     7.1.  Overall Structure of the Module . . . . . . . . . . . . .  11
     7.2.  VPN Profiles  . . . . . . . . . . . . . . . . . . . . . .  12
     7.3.  Modeling a Layer 3 VPN Service  . . . . . . . . . . . . .  13
       7.3.1.  Service Status  . . . . . . . . . . . . . . . . . . .  15
       7.3.2.  Concept of Import/Export Profiles . . . . . . . . . .  15
       7.3.3.  Underlay Transport  . . . . . . . . . . . . . . . . .  16
       7.3.4.  VPN Node  . . . . . . . . . . . . . . . . . . . . . .  17
         7.3.4.1.  RT/RD Assignment/auto-assignment  . . . . . . . .  19
         7.3.4.2.  VPN Network Access  . . . . . . . . . . . . . . .  20
           7.3.4.2.1.  Connection  . . . . . . . . . . . . . . . . .  21
           7.3.4.2.2.  IP Connections  . . . . . . . . . . . . . . .  23



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           7.3.4.2.3.  Security  . . . . . . . . . . . . . . . . . .  27
           7.3.4.2.4.  CE-PE Routing Protocols . . . . . . . . . . .  27
           7.3.4.2.5.  Services  . . . . . . . . . . . . . . . . . .  36
         7.3.4.3.  Multicast . . . . . . . . . . . . . . . . . . . .  42
   8.  Layer 3 Network Model . . . . . . . . . . . . . . . . . . . .  43
   9.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  89
   10. Security Considerations . . . . . . . . . . . . . . . . . . .  89
   11. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  91
   12. Contributors  . . . . . . . . . . . . . . . . . . . . . . . .  91
   13. References  . . . . . . . . . . . . . . . . . . . . . . . . .  92
     13.1.  Normative References . . . . . . . . . . . . . . . . . .  92
     13.2.  Informative References . . . . . . . . . . . . . . . . .  93
   Appendix A.  L3VPN Examples . . . . . . . . . . . . . . . . . . .  96
     A.1.  4G VPN Provisioning Example . . . . . . . . . . . . . . .  96
     A.2.  Multicast VPN Provisioning Example  . . . . . . . . . . . 100
   Appendix B.  Implementation Status  . . . . . . . . . . . . . . . 104
     B.1.  Nokia Implementation  . . . . . . . . . . . . . . . . . . 104
     B.2.  Huawei Implementation . . . . . . . . . . . . . . . . . . 104
     B.3.  Infinera Implementation . . . . . . . . . . . . . . . . . 104
     B.4.  Ribbon-ECI Implementation . . . . . . . . . . . . . . . . 104
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . . 105

1.  Introduction

   [RFC8299] defines a L3VPN Service YANG data Model (L3SM) that can be
   used for communication between customers and network operators.  Such
   model is focused on describing the customer view of the Virtual
   Private Network (VPN) services, and provides an abstracted view of
   the customer's requested services.  That approach limits the usage of
   the L3SM module to the role of a Customer Service Model, according to
   the terminology defined in [RFC8309].

   This document defined a YANG module called L3VPN Network Model
   (L3NM).  The L3NM is aimed at providing a network-centric view of
   Layer 3 (L3) VPN Services.  This data model can be used to facilitate
   communication between the service orchestrator (or a network
   operator) and the network controller/orchestrator by allowing for
   more network-centric information to be included.  It enables further
   capabilities, such as resource management or to serve as a multi-
   domain orchestration interface, where logical resources (such as
   route targets or route distinguishers) must be synchronized.

   This document uses the common VPN YANG module defined in
   [I-D.ietf-opsawg-vpn-common].

   This document does not obsolete, but uses, the definitions in
   [RFC8299].  These two modules are used for similar objectives but
   with different scopes and views.



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   The L3NM YANG module is initially built with a prune and extend
   approach, taking as a starting points the YANG module described in
   [RFC8299].  Nevertheless, this module is not defined as an augment to
   L3SM because a specific structure is required to meet network-
   oriented L3 needs.

   Some of the information captured in the L3SM can be passed by the
   Orchestrator in the L3NM (e.g., customer) or be used to fed some of
   the L3NM attributes (e.g., actual forwarding policies).  Some of the
   information captured in L3SM may be maintained locally within the
   Orchestrator; which is in charge of maintaining the correspondence
   between a Customer view and its network instantiation.  Likewise,
   some of the information captured and exposed using L3NM can fed the
   service layer (e.g., capabilities) to derive L3SM and drive VPN
   service order handling.

   The L3NM does not attempt to address all deployment cases especially
   those where the L3VPN connectivity is supported through the
   coordination of different VPNs in different underlying networks.
   More complex deployment scenarios involving the coordination of
   different VPN instances and different technologies to provide end-to-
   end VPN connectivity are addressed by a complementary YANG model
   defined in [I-D.evenwu-opsawg-yang-composed-vpn].

   L3NM focuses on BGP PE-based Layer 3 VPNs as described in
   [RFC4026][RFC4110][RFC4364] and Multicast VPNs as described in
   [RFC6037][RFC6513][RFC7988].

   The YANG data model in this document conforms to the Network
   Management Datastore Architecture (NMDA) defined in [RFC8342].

2.  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.

3.  Terminology

   This document assumes that the reader is familiar with the contents
   of [RFC6241], [RFC7950], [RFC8299], [RFC8309], and [RFC8453] and uses
   the terminology defined in those documents.

   The meaning of the symbols in tree diagrams is defined in [RFC8340].





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   The document is aimed at modeling BGP PE-based VPNs in a service
   provider network, so the terms defined in [RFC4026] and [RFC4176] are
   used.

   This document makes use of the following terms:

   o  Layer 3 VPN Customer Service Model (L3SM): A YANG module that
      describes the requirements of a L3VPN that interconnects a set of
      sites from the point of view of the customer.  The customer
      service model does not provide details on the service provider
      network.  The L3VPN Customer Service model is defined in
      [RFC8299].

   o  Layer 3 VPN Service Network Model (L3NM): A YANG module that
      describes a VPN Service in the service provider network.  It
      contains information of the Service Provider network and might
      include allocated resources.  It can be used by network
      controllers to manage and control the VPN Service configuration in
      the Service Provider network.  The YANG module can be consumed by
      a Service Orchestrator to request a VPN Service to a Network
      controller.

   o  Service Orchestrator: A functional entity that interacts with the
      customer of a L3VPN.  The Service Orchestrator interacts with the
      customer using L3SM.  The Service Orchestrator is responsible of
      the Customer Edge (CE) - the Provider Edge (PE) attachment
      circuits, the PE selection, and requesting the VPN service to the
      network controller.

   o  Network Orchestrator: A functional entity that is hierarchically
      intermediate between Service Orchestrator and Network Controllers.
      A network orchestrator can manage one or several Network
      Controllers.

   o  Network Controller: A functional entity responsible for the
      control and management of the service provider network.

   o  VPN node: An abstraction that represents a set of policies applied
      on a PE and that belong to a single VPN service.  A VPN service
      involves one or more VPN nodes.  As it is an abstraction, the
      network controller will take on how to implement a VPN node.  For
      example, typically, in a BGP-based VPN, a VPN node could be mapped
      into a Virtual Routing and Forwarding (VRF).

   o  VPN network access: An abstraction that represents the network
      interfaces that are associated to a given VPN node.  Traffic
      coming from the VPN network access belongs to the VPN.  The
      attachment circuits (bearers) between CEs and PEs are terminated



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      in the VPN network access.  A reference to the bearer is
      maintained to allow keeping the link between L3SM and L3NM.

   o  VPN Site: A VPN customer's location that is connected to the
      Service Provider network via a CE-PE link, which can access at
      least one VPN [RFC4176].

   o  VPN Service Provider (SP): A Service Provider that offers VPN-
      related services [RFC4176].

   o  Service Provider (SP) Network: A network that is able to provide
      VPN-related services.

4.  L3NM Reference Architecture

   Figure 1 depicts the reference architecture for L3NM.  The figure is
   an expansion of the architecture presented in Section 5 of [RFC8299]
   and decomposes the box marked "orchestration" in that figure into
   three separate functional components called "Service Orchestration",
   "Network Orchestration", and "Domain Orchestration".

   Although some deployments may choose to construct a monolithic
   orchestration component (covering both service and network matters),
   this document advocates for a clear separation between service and
   network orchestration components for the sake of better flexibility.
   Such design adheres to the L3VPN reference architecture defined in
   Section 1.3 of [RFC4176].  The above separation relies upon a
   dedicated communication interface between these components and
   appropriate YANG module that reflect network-related information
   (that is hidden to customers).

   The intelligence for translating customer-facing information into
   network-centric one is implementation specific.

   The terminology from [RFC8309] is introduced to show the distinction
   between the "Customer Service Model", the "Service Delivery Model",
   the "Network Configuration Model", and the "Device Configuration
   Model".  In that context, the "Domain Orchestration" and "Config
   Manager" roles may be performed by "Controllers".












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                                     +---------------+
                                     |   Customer    |
                                     +---------------+
                     Customer Service Model  |
                            l3vpn-svc        |
                                     +---------------+
                                     |    Service    |
                                     | Orchestration |
                                     +---------------+
                       L3NM Network Model    |
                          l3vpn-ntw          |
                                     +---------------+
                                     |   Network     |
                                     | Orchestration |
                                     +---------------+
               Network Configuration Model   |
                                 +-----------+-----------+
                                 |                       |
                        +---------------+       +---------------+
                        |    Domain     |       |     Domain    |
                        | Orchestration |       | Orchestration |
                        +---------------+       +---------------+
             Device         |        |                   |
             Configuration  |        |                   |
             Model          |        |                   |
                       +---------+   |                   |
                       | Config  |   |                   |
                       | Manager |   |                   |
                       +---------+   |                   |
                            |        |                   |
                            | NETCONF/CLI..................
                            |        |                   |
                     +------------------------------------------------+
                                         Network

                     Figure 1: Reference Architecture

   The L3SM and the L3NM may also be used in the context of the ACTN
   architecture [RFC8453].  Figure 2 shows the Customer Network
   Controller (CNC), the Multi-Domain Service Coordinator (MDSC), and
   the Provisioning Network Controller (PNC).  It also shows the
   interfaces between these functional blocks: the CNC-MDSC Interface
   (CMI), the MDSC-PNC Interface (MPI), and the Southbound Interface
   (SBI).







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                  +----------------------------------+
                  | Customer                         |
                  | +-----------------------------+  |
                  | |             CNC             |  |
                  | +-----------------------------+  |
                  +----:-----------------------:-----+
                       :                       :
                       : L3SM                  : L3SM
                       :                       :
             +---------:---------+   +-------------------+
             | MDSC    :         |   |       MDSC        |
             | +---------------+ |   |     (parent)      |
             | |    Service    | |   +-------------------+
             | | Orchestration | |             :
             | +---------------+ |             : L3NM
             |         :         |             :
             |         : L3NM    |   +-------------------+
             |         :         |   |       MDSC        |
             | +---------------+ |   |      (child)      |
             | |    Network    | |   +-------------------+
             | | Orchestration | |             :
             | +---------------+ |             :
             +---------:---------+             :
                       :                       :
                       : Network Configuration :
                       :                       :
          +------------:-------+     +---------:------------+
          | Domain     :       |     |         : Domain     |
          | Controller :       |     |         : Controller |
          |       +---------+  |     |    +---------+       |
          |       |   PNC   |  |     |    |   PNC   |       |
          |       +---------+  |     |    +---------+       |
          +------------:-------+     +---------:------------+
                       :                       :
                       : Device Configuration  :
                       :                       :
                  +--------+              +--------+
                  | Device |              | Device |
                  +--------+              +--------+

              Figure 2: L3SM and L3NM in the Context of ACTN

5.  Relation with other YANG Models

   The "ietf-vpn-common" module [I-D.ietf-opsawg-vpn-common] includes a
   set of identities, types, and groupings that are meant to be reused
   by VPN-related YANG modules independently of the layer (e.g., Layer
   2, Layer 3) and the type of the module (e.g., network model, service



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   model) including future revisions of existing models (e.g., [RFC8299]
   or [RFC8466]).  The L3NM reuses these common types and grouping.

   In order to avoid data duplication and to ease passing data between
   layers when required (service layer to network layer and vice versa),
   early versions of the L3NM reused many of the data nodes that are
   defined in [RFC8299].  Nevertheless, that approach was abandoned in
   favor of the "ietf-vpn-common" module because that design was
   interpreted as if the deployment of L3NM depends on L3SM, while this
   is not the case.  For example, a Service Provider may decide to use
   the L3NM to build its L3VPN services without exposing the L3SM.

   As discussed in Section 4, the L3NM YANG module is meant to manage
   L3VPN services within a Service Provider network.  The module
   provides a network view of the service.  Such view is only visible
   within the Service Provider and is not exposed outside (to customers,
   for example).  The following discusses how L3NM interfaces with other
   YANG modules:

   L3SM:  L3NM is not a Customer Service Model.

      The internal view of the service (L3NM) may be mapped to an
      external view which is visible to Customers : L3VPN Service YANG
      data Model (L3SM) [RFC8299].

      Typically, the L3NM can be fed with inputs that are requested by
      Customers, typically, relying upon a L3SM template.  Concretely,
      some parts of the L3SM module can be directly mapped into L3NM
      while other parts are generated as a function of the requested
      service and local guidelines.  Some other parts are local to the
      Service Provider and do not map directly to L3SM.

      Note that the use of L3NM within a Service Provider does not
      assume nor preclude exposing the VPN service via L3SM.  This is
      deployment-specific.  Nevertheless, the design of L3NM tries to
      align as much as possible with the features supported by the L3SM
      to ease grafting both L3NM and L3SM for the sake of highly
      automated VPN service provisioning and delivery.

   Network Topology Modules:  A L3VPN involves nodes that are part of a
      topology managed by the Service Provider Backbone network.  Such
      topology can be represented as using the network topology module
      in [RFC8345].

   Device Modules:  L3NM is not a device model.

      Once a global VPN service is captured by means of L3NM, the actual
      activation and provisioning of the VPN service will involve a



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      variety of device modules to tweak the required functions for the
      delivery of the service.  These functions are supported by the VPN
      nodes and can be managed using device YANG modules.  A non-
      comprehensive list of such device YANG modules is provided below:

      *  Routing management [RFC8349].

      *  BGP [I-D.ietf-idr-bgp-model].

      *  PIM [I-D.ietf-pim-yang].

      *  NAT management [RFC8512].

      *  QoS management [I-D.ietf-rtgwg-qos-model].

      *  ACLs [RFC8519].

      How L3NM is used to derive device-specific actions is
      implementation-specific.

6.  Sample Uses of the L3NM Data Model

6.1.  Enterprise Layer 3 VPN Services

   Enterprise L3VPNs are one of the most demanded services for carriers,
   and therefore, L3NM can be useful to automate the tasks of
   provisioning and maintenance of these VPNs.  Templates and batch
   processes can be built, and as a result many parameters are needed
   for the creation from scratch of a VPN that can be abstracted to the
   upper SDN layer and little manual intervention will be still
   required.

   Also common addition/removal of sites of an existing customer VPN can
   benefit of using L3NM, by creation of workflows that either prune or
   add nodes as required from the network data model object.

6.2.  Multi-Domain Resource Management

   The implementation of L3VPN services which span across
   administratively separated domains (i.e., that are under the
   administration of different management systems or controllers)
   requires some network resources to be synchronized between systems.
   Particularly, there are two resources that must be orchestrated and
   manage to avoid asymmetric (non-functional) configuration, or the
   usage of unavailable resources.

   For example, RTs shall be synchronized between PEs.  When every PE is
   controlled by the same management system, RT allocation can be



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   performed by the system.  In cases where the service spans across
   multiple management systems, this task of allocating RTs has to be
   aligned across the domains, therefore, the service model must provide
   a way to specify RTs.  In addition, RDs must also be synchronized to
   avoid collisions in RD allocation between separate systems.  An
   incorrect allocation might lead to the same RD and IP prefixes being
   exported by different PE routers.

6.3.  Management of Multicast Services

   Multicast services over L3VPN can be implemented either using dual
   PIM MVPNs (also known as, Draft Rosen model) [RFC4364] or
   multiprotocol BGP (MBGP)-based MVPNs[RFC6513][RFC6514].  Both methods
   are supported and equally effective, but the main difference is that
   MBGP-based MVPN does not require multicast configuration on the
   service provider backbone.  MBGP MVPNs employ the intra-autonomous
   system BGP control plane and PIM sparse mode as the data plane.  The
   PIM state information is maintained between the PE routers using the
   same architecture that is used for unicast VPNs.

   On the other hand, Draft Rosen has limitations such as reduced
   options for transport, control plane scalability, availability,
   operational inconsistency, and the need of maintaining state in the
   backbone.  Because of this, MBGP MVPN is the architectural model that
   has been taken as the base for implementing multicast service on
   L3VPN.  In this scenario, BGP auto discovery is used to discover MVPN
   PE members and the customer PIM signaling is sent across provider
   core through MP-BGP.  The multicast traffic is transported on MPLS
   P2MP LSPs.  All of the previous information is carried in the MCAST-
   VPN BGP NRLI.

7.  Description of the L3NM YANG Module

   The L3NM ('ietf-l3vpn-ntw') is defined to manage L3VPNs in a service
   provider network.  In particular, the 'ietf-l3vpn-ntw' module can be
   used to create, modify, and retrieve L3VPN Services of a network.

7.1.  Overall Structure of the Module

   The 'ietf-l3vpn-ntw' module uses two main containers: 'vpn-services'
   and 'vpn-profiles' (see Figure 3).

   The 'vpn-services' container maintains the set of VPN services
   managed within the service provider's network. 'vpn-service' is the
   data structure that abstracts a VPN service (Section 7.3).






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   The 'vpn-profiles' container is used by the provider to maintain a
   set of common VPN profiles that apply to one or several VPN services
   (Section 7.2).

   module: ietf-l3vpn-ntw
     +--rw l3vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
            +--rw vpn-service* [vpn-id]
               ...

                   Figure 3: Overall L3NM Tree Structure

7.2.  VPN Profiles

   The 'vpn-profiles' container (Figure 4) allows the network provider
   to define and maintain a set of common VPN profiles
   [I-D.ietf-opsawg-vpn-common] that apply to one or several VPN
   services.  The exact definition of the profiles is local to each
   network provider.

   This document does not make any assumption about the exact definition
   of these profiles.  How such profiles are defined is deployment
   specific.  The model only includes an identifier to these profiles to
   ease identifying local policies when building a VPN service.  As
   shown in Figure 4, the following identifiers can be included:

   o  'cloud-identifier': This identifier refers to a cloud service.

   o  'encryption-profile-identifier': An encryption profile refers to a
      set of policies related to the encryption scheme(s) and setup that
      can be applied when building and offering a VPN service.

   o  'qos-profile-identifier': A QoS profile refers to as set of
      policies such as classification, marking, and actions (e.g.,
      [RFC3644]).

   o  'bfd-profile-identifier': A Bidirectional Forwarding Detection
      (BFD) profile refers to a set of BFD [RFC5880] policies that can
      be invoked when building a VPN service.

   o  'forwarding-profile-identifier': A forwarding profile refers to
      the policies that apply to the forwarding of packets conveyed
      within a VPN.  Such policies may consist at applying Access
      Control Lists (ACLs).





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   o  'routing-profile-identifier': A routing profile refers to a set of
      routing policies that will be invoked (e.g., BGP policies).

            +--rw l3vpn-ntw
               +--rw vpn-profiles
               |  +--rw valid-provider-identifiers
               |     +--rw cloud-identifier* [id] {cloud-access}?
               |     |  +--rw id    string
               |     +--rw encryption-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw qos-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw bfd-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw forwarding-profile-identifier* [id]
               |     |  +--rw id    string
               |     +--rw routing-profile-identifier* [id]
               |        +--rw id    string
               +--rw vpn-services
                  ...

                 Figure 4: VPN Profiles Subtree Structure

7.3.  Modeling a Layer 3 VPN Service

   The 'vpn-service' is the data structure that abstracts a VPN service
   in the service provider network.  Each 'vpn-service' is uniquely
   identified by an identifier: 'vpn-id'.  Such 'vpn-id' is only
   meaningful locally within the Network controller.

   In order to facilitate the identification of the service, 'customer-
   name' and 'description' attributes may be provided.

   The main 'vpn-service' parameters are:

   o  'status': Allows the control of the operative and administrative
      status of the service as a whole.

   o  'vpn-id': Is an identifier that is used to uniquely identify the
      L3VPN Service within L3NM scope.

   o  'l3sm-vpn-id': Refers to an identifier of L3SM service.  This
      identifier allows to easily correlate the (network) service as
      built in the network with a service order.

   o  'vpn-service-topology': Indicates the network topology for the
      service: Hub-Spoke, Any-to-Any, and Custom.  The deployment on the




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      network is defined by the correct usage of import and export
      profiles

   o  'vpn-type': Indicate the VPN service signaling type.

   o  'ie-profiles': Defines reusable import/export policies for the
      same 'vpn-service'.  More details are provided in Section 7.3.2.

   o  'underlay-transport': Describes the preference for the transport
      technology to carry the traffic of the VPN service
      (Section 7.3.3).

   The 'vpn-node' is an abstraction that represents a set of policies
   applied to a network node and that belong to a single 'vpn-service'.
   A VPN service is typically built by adding instances of 'vpn-node' to
   the 'vpn-nodes' container.

   A 'vpn-node' contains 'vpn-network-accesses', which are the
   interfaces attached to the VPN by which the customer traffic is
   received.  Therefore, the customer sites are connected to the 'vpn-
   network-accesses'.

   Note that, as this is a network data model, the information about
   customers sites is not required in the model.  Such information is
   rather relevant in the L3SM.

     +--rw l3vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
           +--rw vpn-service* [vpn-id]
              +--rw status
              |  ...
              +--rw vpn-id                  vpn-common:vpn-id
              +--rw vpn-name?               string
              +--rw vpn-description?        string
              +--rw customer-name?          string
              +--rw l3sm-vpn-id?            vpn-common:vpn-id
              +--rw vpn-type?               identityref
              +--rw vpn-service-topology?   identityref
              +--rw ie-profiles
              |  ...
              +--rw underlay-transport
              |  ...
              +--rw vpn-nodes
                 ...

                 Figure 5: VPN Services Subtree Structure



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7.3.1.  Service Status

   The L3NM allows to track service status ('status') of a given VPN
   service (Figure 6).  Both operational and administrative status are
   maintained together with a timestamp.  For example, a service can be
   created but not put into effect.

   'admin' and 'ops' status can be used as trigger to detect service
   anomalies.  For example, a service that is declared at the service
   layer as active but still inactive at the network layer is an
   indication that network provision actions are needed to align the
   observed service with the expected service status.

     +--rw l3vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
           +--rw vpn-service* [vpn-id]
              +--rw status
              |  +--rw admin-status
              |  |  +--rw status?         identityref
              |  |  +--rw last-updated?   yang:date-and-time
              |  +--ro oper-status
              |     +--ro status?         identityref
              |     +--ro last-updated?   yang:date-and-time
              ...

              Figure 6: VPN Service Status Subtree Structure

7.3.2.  Concept of Import/Export Profiles

   The import and export profiles construct contains a list with
   information related with route target and distinguishers (RTs and
   RDs), grouped and identified by 'ie-profile-id'.  The identifier is
   then referenced in one or multiple 'vpn-nodes' so the controller can
   identify RTs and RDs to be configured for a given VRF.  The subtree
   is shown in Figure 7.














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     +--rw l3vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
           +--rw vpn-service* [vpn-id]
              +--rw vpn-id                  vpn-common:vpn-id
              +  ...
              +--rw ie-profiles
              |  +--rw ie-profile* [ie-profile-id]
              |     +--rw ie-profile-id    string
              |     +--rw rd?              union
              |     +--rw vpn-targets
              |        +--rw vpn-target* [id]
              |        |  +--rw id                   int8
              |        |  +--rw route-targets* [route-target]
              |        |  |  +--rw route-target    rt-types:route-target
              |        |  +--rw route-target-type
              |        |          rt-types:route-target-type
              |        +--rw vpn-policies
              |           +--rw import-policy?   string
              |           +--rw export-policy?   string
              +--rw vpn-nodes
                 +--rw vpn-node* [ne-id]
                    +--rw ne-id                      string
                    ...
                    +--rw vpn-targets
                    |  +--rw vpn-target* [id]
                    |  |  +--rw id                   int8
                    |  |  +--rw route-targets* [route-target]
                    |  |  |  +--rw route-target    rt-types:route-target
                    |  |  +--rw route-target-type
                    |  |          rt-types:route-target-type
                    |  +--rw vpn-policies
                    |     +--rw import-policy?   string
                    |     +--rw export-policy?   string
                    ...

           Figure 7: Subtree Structure of Import/Export Profiles

7.3.3.  Underlay Transport

   The model allows to indicate a preference for the underlay transport
   technology when activating a L3VPN service (Figure 8).  This
   preference is especially useful in networks with multiple domains and
   NNI types.  This version of the YANG module supports these options:
   BGP, LDP, GRE, SR, SR-TE, and RSVP-TE as underlay transport
   mechanisms.  Other profiles can be defined in the future.




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     +--rw l3vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
           +--rw vpn-service* [vpn-id]
              +--rw vpn-id                  vpn-common:vpn-id
              +  ...
              +--rw underlay-transport
              |  +--rw type*   identityref
              +--rw vpn-nodes
                 +--rw vpn-node* [ne-id]
                 ...

          Figure 8: Subtree Structure of the Underlying Transport

7.3.4.  VPN Node

   The 'vpn-node' is an abstraction that represents a set of common
   policies applied on a given network node (tipcally, a PE) and belong
   to one L3VPN service.  In order to indicate the network nodes where
   the 'vpn-node' applies, the 'ne-id' must be indicated.  The 'vpn-
   node' includes a parameter to indicate the network node on which it
   is applied.  In the case that the 'ne-id' points to a specific PE,
   the 'vpn-node' will likely be mapped into a VRF in the node.
   However, the model also allows to point to an abstract node.  In this
   case, the network controller will decide how to split the 'vpn-node'
   into VRFs.  Some 'vpn-node' parameters are listed below:

   o  local-autonomous-system: Refers to the autonomous system number
      that is locally configured in the instance.  It can be overwritten
      for specific purposes in the CE-PE BGP session.

   o  maximum-routes: Set the maximum number of prefixes allowed in the
      'vpn-node' instance.  This value is typically set in the service
      request.

   o  'rd' and 'vpn-targets': For the cases the logical resources are
      managed outside the network controller, the model allows to
      explicitely indicate the logical resources such as Route targets
      (RTs) and Route Distinguishers (RDs) (RT,RD).

   o  Multicast: Enable multicast traffic inside the VPN.  Refer to
      Section 7.3.4.3.

   Under the VPN Node ('vpn-node') container, VPN Network Accesses
   ('vpn-network-access') can be created.  The VPN Network Access
   represents the point to which sites are connected.  Note that, unlike
   in L3SM, the L3NM does not need to model the customer site, only the



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   points where the traffic from the site are received (i.e., the PE
   side of PE-CE connections).  Hence, the VPN Network access contains
   the connectivity information between the provider's network and the
   customer premises.  The VPN profiles ('vpn-profiles') have a set of
   routing policies than can be applied during the service creation.

   The L3NM allows to track the status ('status') of the nodes involved
   in a VPN service.  Both operational and administrative status are
   maintained.  Mismatch between an administrative status vs.  the
   operational status can be used as trigger to detect anomalies.

     +--rw l3vpn-ntw
        +--rw vpn-profiles
        |  ...
        +--rw vpn-services
           +--rw vpn-service* [vpn-id]
              +--rw vpn-id                  vpn-common:vpn-id
              ...
              +--rw vpn-nodes
                 +--rw vpn-node* [ne-id]
                    +--rw vpn-node-id?               union
                    +--rw local-autonomous-system?   inet:as-number
                    +--rw description?               string
                    +--rw ne-id                      string
                    +--rw router-id?                 inet:ip-address
                    +--rw address-family?
                    |       vpn-common:address-family
                    +--rw node-role?                 identityref
                    +--rw rd?                        union
                    +--rw vpn-targets
                    |  +--rw vpn-target* [id]
                    |  |  +--rw id                   int8
                    |  |  +--rw route-targets* [route-target]
                    |  |  |  +--rw route-target    rt-types:route-target
                    |  |  +--rw route-target-type
                    |  |          rt-types:route-target-type
                    |  +--rw vpn-policies
                    |     +--rw import-policy?   string
                    |     +--rw export-policy?   string
                    +--rw status
                    |  +--rw admin-status
                    |  |  +--rw status?         identityref
                    |  |  +--rw last-updated?   yang:date-and-time
                    |  +--ro oper-status
                    |     +--ro status?         identityref
                    |     +--ro last-updated?   yang:date-and-time
                    +--rw node-ie-profile?           leafref
                    +--rw groups



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                    |  +--rw group* [group-id]
                    |     +--rw group-id    string
                    +--rw vpn-network-accesses
                    |  +--rw vpn-network-access* [id]
                    |     ...
                    +--rw maximum-routes
                    |  +--rw address-family* [af]
                    |     +--rw af
                    |     |       vpn-common:address-family
                    |     +--rw maximum-routes?   uint32
                    +--rw multicast {vpn-common:multicast}?
                       ...

                   Figure 9: VPN Node Subtree Structure

7.3.4.1.  RT/RD Assignment/auto-assignment

   For the cases the logical resources are managed outside the network
   controller, the model allows to explicitely indicate the logical
   resources such as Route targets (RTs) and Route Distinguishers (RDs)
   (RT,RD).

   Three possible behaviors are needed to fulfil the identified use
   cases:

   o  The network controller auto-assigns logical resources (RTs, RDs).
      This can apply for new services deployment.

   o  The Network Operator/Service orchestrator assigns explicitly the
      RTs and RDs.  This case will fit with a brownfield scenario where
      some existing services needs to be updated by the network
      operators.

   o  The Network Operator/Service orchestrator explicitly wants NO RT/
      RD to be assigned.  This case will fit in VRF-Lite scenarios, CE
      testing inside the Network or just for troubleshooting pruposes.

   Thus a union between two yang data types are included in order to
   support this scenarios.  So, if the leaf is not created in the Yang
   the expected behavior is the auto-assigns.  If the Leaf is created
   with a valid rd value it will be explicitly assign in the VPN Node
   and if the leaf is created with an empty value, the RD value will not
   be deployed in the VPN node.








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7.3.4.2.  VPN Network Access

   A 'vpn-network-access' represents an entry point to a VPN service
   (Figure 10).  In other words, this container encloses the parameters
   that describe the access information for the traffic that belongs to
   a particular L3VPN.  As such, every 'vpn-network-access' MUST belong
   to one and only one 'vpn-node'.

   A 'vpn-network-access' includes information such as the connection on
   which the access is defined (see Section 7.3.4.2.1), the
   encapsulation of the traffic, policies that are applied on the
   access, etc.

   Each 'vpn-network-access' SHOULD have a 'vpn-network-access-type' to
   select the type of network interface to be deployed in the devices.
   The available options are:

   o  Point-to-Point: The point-to-point type represent a direct
      connection between the end-points.  It implies the controller must
      keep the association between a logical or physical interface on
      the device with the 'id' of the vpn-network-access.

   o  Multipoint: This option represents a broadcast connection between
      end-points.  It implies the controller must keep the association
      between a logical or physical interface on the device with the
      'id' of the 'vpn-network-access'.

   o  Pseudowire: Represent a connection coming from an L2VPN service.
      It implies the controller must keep the relationship between the
      logical tunnels or bridges on the devices with the 'id' of the'
      vpn-network-access'.

   o  Loopback: It represents the creation of a logical interface on the
      devices.

   A PNC [RFC8453] will accept VPN requests containing this construct,
   using the enclosed data to: configure the router's interface to
   include the parameters described at the 'vpn-network-access', include
   the given interface into a VRF, configuring policies or schedulers
   for processing the incoming traffic, etc.











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    ...
    +--rw vpn-services
       +--rw vpn-service* [vpn-id]
          +--rw vpn-id                  vpn-common:vpn-id
          +  ...
           +--rw vpn-node* [ne-id]
              +--rw ne-id                      string
              + ...
              +--rw vpn-network-accesses
              |  +--rw vpn-network-access* [id]
              |     +--rw id
              |     |       vpn-common:vpn-id
              |     +--rw port-id?
              |     |       vpn-common:vpn-id
              |     +--rw description?               string
              |     +--rw status
              |     |  +--rw admin-enabled?   boolean
              |     |  +--ro oper-status?     operational-type
              |     +--rw vpn-network-access-type?   identityref
              |     +--rw connection
              |     |  ...
              |     +--rw ip-connection
              |     |  ...
              |     +--rw security
              |     |  ...
              |     +--rw routing-protocols
              |     |  ...
              |     +--rw service
              |        ...
              ...

               Figure 10: VPN Network Access Tree Structure

7.3.4.2.1.  Connection

   The definition of a L3VPN is commonly specified not only at the IP
   layer, but also requires to identify parameters at the Ethernet
   layer, such as encapsulation type (e.g., VLAN, QinQ, QinAny, VxLAN,
   etc.).  The 'connection' container represents and groups the set of
   Layer 2 connectivity from where the traffic of the L3VPN in a
   particular VPN Network access is coming.

   Ethernet encapsulation description is not supported in [RFC8299].
   However, this parameters are mandatory to configure the PE
   interfaces.  Thus, in the L3NM, these parameters uses the connection
   container inside the 'vpn-network-access'.  This container defines
   protocols and parameters to enable connectivity at Layer 2.




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    ...
    +--rw vpn-services
       +--rw vpn-service* [vpn-id]
          +--rw vpn-id                  vpn-common:vpn-id
          +  ...
           +--rw vpn-node* [ne-id]
              +--rw ne-id                      string
              + ...
              +--rw vpn-network-accesses
              |  +--rw vpn-network-access* [id]
              |     +--rw id
              |     |       vpn-common:vpn-id
              |     ...
              |     +--rw connection
              |     |  +--rw encapsulation-type?   identityref
              |     |  +--rw logical-interface
              |     |  |  +--rw peer-reference?   uint32
              |     |  +--rw tagged-interface
              |     |  |  +--rw type?                identityref
              |     |  |  +--rw dot1q-vlan-tagged
              |     |  |  |       {vpn-common:dot1q}?
              |     |  |  |  +--rw tag-type?   identityref
              |     |  |  |  +--rw cvlan-id?   uint16
              |     |  |  +--rw priority-tagged
              |     |  |  |  +--rw tag-type?   identityref
              |     |  |  +--rw qinq {vpn-common:qinq}?
              |     |  |  |  +--rw tag-type?   identityref
              |     |  |  |  +--rw svlan-id    uint16
              |     |  |  |  +--rw cvlan-id    uint16
              |     |  |  +--rw qinany {vpn-common:qinany}?
              |     |  |  |  +--rw tag-type?   identityref
              |     |  |  |  +--rw svlan-id    uint16
              |     |  |  +--rw vxlan {vpn-common:vxlan}?
              |     |  |     +--rw vni-id       uint32
              |     |  |     +--rw peer-mode?   identityref
              |     |  |     +--rw peer-list* [peer-ip]
              |     |  |        +--rw peer-ip    inet:ip-address
              |     |  +--rw bearer
              |     |     ...
              ...

                Figure 11: Encapsulation Subtree Structure

   Additionally, the 'bearer-reference' and the pseudowire termination
   are supported (see Figure 12).  A site, as per [RFC4176] represents a
   VPN customer's location that is connected to the Service Provider
   network via a CE-PE link, which can access at least one VPN.  The
   connection from the site to the Service Provider network is the



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   bearer.  Every site is associated with a list of bearers.  A bearer
   is the layer two connections with the site.  In the module it is
   assumed that the bearer has been allocated by the Service Provider at
   the service orchestration step.  The bearer is associated to a
   network element and a port.  Hence, a bearer is just a bearer-
   reference to allow the translation between L3SM and L3NM.

   ...
   +--rw vpn-network-accesses
   |  +--rw vpn-network-access* [id]
   |     +--rw id
   |     |       vpn-common:vpn-id
   |     ...
   |     +--rw vpn-network-access-type?   identityref
   |     +--rw connection
   |     |  ...
   |     |  +--rw bearer
   |     |     +--rw bearer-reference?   string
   |     |     |       {vpn-common:bearer-reference}?
   |     |     +--rw pseudowire
   |     |     |  +--rw vcid?      uint32
   |     |     |  +--rw far-end?   union
   |     |     +--rw vpls
   |     |        +--rw vcid?      union
   |     |        +--rw far-end?   union
   |  ...

                    Figure 12: Bearer Subtree Structure

7.3.4.2.2.  IP Connections

   IP connection container (Figure 13) has the parameters of the 'vpn-
   network-access' addressing information.  The address allocated in
   this container would represent the PE interface address
   configuration.  The IP connection container is designed to support
   both IPv4 and IPv6.  It also supports three IP address assignment
   modes: SLAAC [RFC7527], Provider DHCP, DHCP relay, and static
   addressing.  Only one of them is enabled for a given service.

      ...
      +--rw vpn-network-accesses
      |  +--rw vpn-network-access* [id]
      |     +--rw id
      |     |       vpn-common:vpn-id
      |     ...
      |     +--rw vpn-network-access-type?   identityref
      |     +--rw connection
      |     |  ...



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      |     +--rw ip-connection
      |     |  +--rw ipv4 {vpn-common:ipv4}?
      |     |  |  +--rw address-allocation-type?
      |     |  |  |       identityref
      |     |  |  +--rw (allocation-type)?
      |     |  |     +--:(provider-dhcp)
      |     |  |     |  +--rw provider-address?
      |     |  |     |  |       inet:ipv4-address
      |     |  |     |  +--rw prefix-length?
      |     |  |     |  |       uint8
      |     |  |     |  +--rw (address-assign)?
      |     |  |     |     +--:(number)
      |     |  |     |     |  +--rw number-of-dynamic-address?
      |     |  |     |     |          uint16
      |     |  |     |     +--:(explicit)
      |     |  |     |        +--rw customer-addresses
      |     |  |     |           +--rw address-group*
      |     |  |     |                   [group-id]
      |     |  |     |              +--rw group-id
      |     |  |     |              |       string
      |     |  |     |              +--rw start-address?
      |     |  |     |              |       inet:ipv4-address
      |     |  |     |              +--rw end-address?
      |     |  |     |                      inet:ipv4-address
      |     |  |     +--:(dhcp-relay)
      |     |  |     |  +--rw dr-provider-address?
      |     |  |     |  |       inet:ipv4-address
      |     |  |     |  +--rw dr-prefix-length?
      |     |  |     |  |       uint8
      |     |  |     |  +--rw customer-dhcp-servers
      |     |  |     |     +--rw server-ip-address*
      |     |  |     |             inet:ipv4-address
      |     |  |     +--:(static-addresses)
      |     |  |        ...
      |     |  +--rw ipv6 {vpn-common:ipv6}?
      |     |  |  +--rw address-allocation-type?
      |     |  |  |       identityref
      |     |  |  +--rw (allocation-type)?
      |     |  |     +--:(provider-dhcp)
      |     |  |     |  +--rw (provider-dhcp)?
      |     |  |     |     +--:(provider-address)
      |     |  |     |     |  +--rw provider-address?
      |     |  |     |     |          inet:ipv6-address
      |     |  |     |     +--:(prefix-length)
      |     |  |     |     |  +--rw prefix-length?
      |     |  |     |     |          uint8
      |     |  |     |     +--:(address-assign)
      |     |  |     |        +--rw (address-assign)?



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      |     |  |     |           +--:(number)
      |     |  |     |           |  +--rw number-of-dynamic-address?
      |     |  |     |           |          uint16
      |     |  |     |           +--:(explicit)
      |     |  |     |              +--rw customer-addresses
      |     |  |     |                 +--rw address-group*
      |     |  |     |                         [group-id]
      |     |  |     |                    +--rw group-id
      |     |  |     |                    |       string
      |     |  |     |                    +--rw start-address?
      |     |  |     |                    |       inet:ipv6-address
      |     |  |     |                    +--rw end-address?
      |     |  |     |                            inet:ipv6-address
      |     |  |     +--:(dhcp-relay)
      |     |  |     |  +--rw dr-provider-address?
      |     |  |     |  |       inet:ipv6-address
      |     |  |     |  +--rw dr-prefix-length?
      |     |  |     |  |       uint8
      |     |  |     |  +--rw customer-dhcp-servers
      |     |  |     |     +--rw server-ip-address*
      |     |  |     |             inet:ipv6-address
      |     |  |     +--:(static-addresses)
      |     |  |        ...

                Figure 13: IP Connection Subtree Structure

   In the case of the static addressing (Figure 14), the model supports
   the assignment of several IP addresses in the same 'vpn-network-
   access'.  To identify which of the addresses is the primary address
   of a connection ,the 'primary-address' reference MUST be set with the
   corresponding 'address-id'.




















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              ...
              +--rw vpn-network-accesses
                 |  +--rw vpn-network-access* [id]
                 |     +--rw id
                 |     |       vpn-common:vpn-id
                 |     ...
                 |     +--rw vpn-network-access-type?   identityref
                 |     +--rw connection
                 |     |  ...
                 |     +--rw ip-connection
                 |     |  +--rw ipv4 {vpn-common:ipv4}?
                 |     |  |  +--rw address-allocation-type?
                 |     |  |  |       identityref
                 |     |  |  +--rw (allocation-type)?
                 |     |  |     ...
                 |     |  |     +--:(static-addresses)
                 |     |  |        +--rw primary-address?
                 |     |  |        |       -> ../address/address-id
                 |     |  |        +--rw address* [address-id]
                 |     |  |           +--rw address-id
                 |     |  |           |       string
                 |     |  |           +--rw s-provider-address?
                 |     |  |           |       inet:ipv4-address
                 |     |  |           +--rw s-customer-address?
                 |     |  |           |       inet:ipv4-address
                 |     |  |           +--rw s-prefix-length?
                 |     |  |                   uint8
                 |     |  +--rw ipv6 {vpn-common:ipv6}?
                 |     |  |  +--rw address-allocation-type?
                 |     |  |  |       identityref
                 |     |  |  +--rw (allocation-type)?
                 |     |  |     ...
                 |     |  |     +--:(static-addresses)
                 |     |  |        +--rw s-primary-address?
                 |     |  |        |       -> ../s-address/address-id
                 |     |  |        +--rw s-address* [address-id]
                 |     |  |           +--rw address-id
                 |     |  |           |       string
                 |     |  |           +--rw provider-address?
                 |     |  |           |       inet:ipv6-address
                 |     |  |           +--rw customer-address?
                 |     |  |           |       inet:ipv6-address
                 |     |  |           +--rw prefix-length?      uint8
                 ...

          Figure 14: IP Connection Subtree Structure: Static Mode





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7.3.4.2.3.  Security

   The 'security' container specifies the authentication and the
   encryption to be applied for a given VPN network access (Figure 15).

              ...
              +--rw vpn-network-accesses
              |  +--rw vpn-network-access* [id]
              |     +--rw id
              |     |       vpn-common:vpn-id
              |     +  ...
              |     +--rw connection
              |     |  ...
              |     +--rw ip-connection
              |     |  ...
              |     +--rw security
              |     |  +--rw encryption {vpn-common:encryption}?
              |     |  |  +--rw enabled?   boolean
              |     |  |  +--rw layer?     enumeration
              |     |  +--rw encryption-profile
              |     |     +--rw (profile)?
              |     |     |  +--:(provider-profile)
              |     |     |  |  +--rw profile-name?    leafref
              |     |     |  +--:(customer-profile)
              |     |     |     +--rw algorithm?       string
              |     |     +--rw (key-type)?
              |     |        +--:(psk)
              |     |           +--rw preshared-key?   string
              |     +--rw routing-protocols
              |     |  ...
              |     +--rw service
              |        ...
              |  ...

                   Figure 15: Security Subtree Structure

7.3.4.2.4.  CE-PE Routing Protocols

   The model allows the Provider to configure one or more routing
   protocols associated with a particular 'vpn-network-access'
   (Figure 16).  This protocol will run between the PE and the CE.  A
   routing protocol instance MUST have a type (e.g., bgp, ospf) and an
   identifier.  The identifier is necessary when multiple instances of
   the same protocol have to be configured.







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                    ...
                    +--rw vpn-network-accesses
                    |  +--rw vpn-network-access* [id]
                    |     +--rw id
                    |     |       vpn-common:vpn-id
                    |     ...
                    |     +--rw ip-connection
                    |     |  ...
                    |     +--rw routing-protocols
                    |     |  +--rw routing-protocol* [id]
                    |     |     +--rw id                  string
                    |     |     +--rw type?               identityref
                    |     |     +--rw routing-profiles* [id]
                    |     |     |  +--rw id      leafref
                    |     |     |  +--rw type?   identityref
                    |     |     +--rw ospf {vpn-common:rtg-ospf}?
                    |     |     |  ...
                    |     |     +--rw bgp {vpn-common:rtg-bgp}?
                    |     |     |  ...
                    |     |     +--rw isis {vpn-common:rtg-isis}?
                    |     |     |  ...
                    |     |     +--rw static
                    |     |     |  ...
                    |     |     +--rw rip {vpn-common:rtg-rip}?
                    |     |     |  +--rw address-family*
                    |     |     |          vpn-common:address-family
                    |     |     +--rw vrrp {vpn-common:rtg-vrrp}?
                    |     |        +--rw address-family*
                    |     |                vpn-common:address-family
                    |     +--rw service
                    |        ...
                    ...

                   Figure 16: Routing Subtree Structure

   Routing configuration does not include low-level policies.  These
   policies are low level device configurations that must not be part of
   an abstracted model.  A provider's internal policies (such as
   security filters) will be implemented as part of the device
   configuration but does not require any input from this model.  Some
   policies like primary/backup or load-balancing can be inferred from
   'access-priority'.

   When configuring multiple instances of the same routing protocol,
   this does not automatically imply that, from a device configuration
   perspective, there will be parallel instances (multiple processes)
   running.  It will be up to the implementation to use the most
   appropriate deployment model.  As an example, when multiple BGP peers



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   need to be implemented, multiple instances of BGP must be configured
   as part of this model.  However, from a device configuration point of
   view, this could be implemented as:

   o  Multiple BGP processes with a single neighbor running in each
      process.

   o  A single BGP process with multiple neighbors running.

   o  A combination of both.

   To be aligned with [RFC8299], this model supports the following CE-PE
   routing protocols:

   o  OSPF: The model (Figure 17) allows the user to configure OSPF to
      run as routing protocol on the 'vpn-network-access interface'.  An
      OSPF instance can be bound to IPv4, IPv6 or both.  When only IPv4
      address-family is requested, it will be up to the implementation
      to drive whether OSPFv2 or OSPFv3 is used.
































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                    ...
                    +--rw vpn-network-accesses
                    |  +--rw vpn-network-access* [id]
                    |     +--rw id
                    |     |       vpn-common:vpn-id
                    |     ...
                    |     +--rw ip-connection
                    |     |  ...
                    |     +--rw routing-protocols
                    |     |  +--rw routing-protocol* [id]
                    |     |     +--rw id                  string
                    |     |     +--rw type?               identityref
                    |     |     +--rw routing-profiles* [id]
                    |     |     |  +--rw id      leafref
                    |     |     |  +--rw type?   identityref
                    |     |     +--rw ospf {vpn-common:rtg-ospf}?
                    |     |     |  +--rw address-family*
                    |     |     |  |       vpn-common:address-family
                    |     |     |  +--rw area-address
                    |     |     |  |       yang:dotted-quad
                    |     |     |  +--rw metric?           uint16
                    |     |     |  +--rw mtu?              uint16
                    |     |     |  +--rw process-id?       uint16
                    |     |     |  +--rw security
                    |     |     |  |  +--rw auth-key?   string
                    |     |     |  +--rw sham-links
                    |     |     |       {vpn-common:rtg-ospf-sham-link}?
                    |     |     |     +--rw sham-link* [target-site]
                    |     |     |        +--rw target-site
                    |     |     |        |       vpn-common:vpn-id
                    |     |     |        +--rw metric?        uint16
                    |     |     +--rw bgp {vpn-common:rtg-bgp}?
                    |     |     |  ...
                    |     |     +--rw isis {vpn-common:rtg-isis}?
                    |     |     |  ...
                    |     |     +--rw static
                    |     |     |  ...
                    |     |     +--rw rip {vpn-common:rtg-rip}?
                    |     |     |  ...
                    |     |     +--rw vrrp {vpn-common:rtg-vrrp}?
                    |     |        ...
                    |     +--rw service
                    |        ...
                    ...

                 Figure 17: OPSF Routing Subtree Structure





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   o  BGP: The model (Figure 18) allows to configure a BGP neighbor,
      including a set for parameters that are pertinent to be tweaked at
      the network level for service customization purposes.  This
      container does not aim to include every BGP parameter; a
      comprehensive set of parameters belongs more to the BGP device
      model.  The following parameters are captured in Figure 18.  It is
      up to the implementation to drive the corresponding BGP device
      configuration.

      *  'peer-autonomous-system': This parameter conveys the Customer's
         AS Number (ASN).

      *  'local-autonomous-system': This parameter is set of AS override
         is activated for this peer.

      *  'address-family': This attribute indicates the address-family
         of the peer.  It can be set to IPv4, IPv6, or both address-
         families.

      *  'neighbor': The module supports supplying two neighbors (each
         for a given address-family) or one neighbor (if 'address-
         family' attribute is set to both IPv4 and IPv6 address-
         families).  A list of IP address(es) of the BGP neighbor can be
         then conveyed in this parameter.

      *  'multihop': This attribute indicates the number of allowed IP
         hops between a BGP peer and a PE.

      *  'security': The authentication type will be driven by the
         implementation but the module supports any authentication that
         uses a key as a parameter.

      *  'as-override': If set, this parameter indicates whether AS
         override is enabled, i.e., replace the ASN of the peer
         specified in the AS Path attribute with the ASN identified by
         the 'local-autonomous-system' attribute.

      *  'default-route': This attribute controls whether default
         route(s) can be advertised to the peer.

      *  'bgp-max-prefix': This attribute is used to control how many
         prefixes can be received from a neighbor.  If reached, the BGP
         session will be teared down.

      *  'bgp-timer': Two timers can be captured in this container: (1)
         'hold-time' which is the time interval that will be used for
         the HoldTimer (Section 4.2 of [RFC4271]) when establishing a
         BGP session. (2) 'keep-alive' which is the time interval for



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         the KeepAlive timer between a PE and a BGP peer (Section 4.4 of
         [RFC4271]).

                    ...
                    +--rw vpn-network-accesses
                    |  +--rw vpn-network-access* [id]
                    |     +--rw id
                    |     |       vpn-common:vpn-id
                    |     ...
                    |     +--rw ip-connection
                    |     |  ...
                    |     +--rw routing-protocols
                    |     |  +--rw routing-protocol* [id]
                    |     |     +--rw id                  string
                    |     |     +--rw type?               identityref
                    |     |     +--rw routing-profiles* [id]
                    |     |     |  +--rw id      leafref
                    |     |     |  +--rw type?   identityref
                    |     |     +--rw ospf {vpn-common:rtg-ospf}?
                    |     |     |  ...
                    |     |     +--rw bgp {vpn-common:rtg-bgp}?
                    |     |     |  +--rw peer-autonomous-system
                    |     |     |  |           inet:as-number
                    |     |     |  +--rw local-autonomous-system?
                    |     |     |  |       inet:as-number
                    |     |     |  +--rw address-family*
                    |     |     |  |      vpn-common:address-family
                    |     |     |  +--rw neighbor*
                    |     |     |  |       inet:ip-address
                    |     |     |  +--rw multihop?            uint8
                    |     |     |  +--rw security
                    |     |     |  |  +--rw auth-key?   string
                    |     |     |  +--rw status
                    |     |     |  |  +--rw admin-status
                    |     |     |  |  |  +--rw status?       identityref
                    |     |     |  |  |  +--rw last-updated?
                    |     |     |  |  |  |            yang:date-and-time
                    |     |     |  |  +--ro oper-status
                    |     |     |  |     +--ro status?       identityref
                    |     |     |  |     +--ro last-updated?
                    |     |     |  |                  yang:date-and-time
                    |     |     |  +--rw description?             string
                    |     |     |  +--rw as-override?            boolean
                    |     |     |  +--rw default-route?          boolean
                    |     |     |  +--rw bgp-max-prefix
                    |     |     |  |  +--rw max-prefix?           uint32
                    |     |     |  |  +--rw warning-threshold? decimal64
                    |     |     |  |  +--rw violate-action?  enumeration



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                    |     |     |  |  +--rw restart-interval?     uint16
                    |     |     |  +--rw bgp-timer
                    |     |     |     +--rw keep-alive?   uint16
                    |     |     |     +--rw hold-time?    uint16
                    |     |     +--rw isis {vpn-common:rtg-isis}?
                    |     |     |  ...
                    |     |     +--rw static
                    |     |     |  ...
                    |     |     +--rw rip {vpn-common:rtg-rip}?
                    |     |     |  ...
                    |     |     +--rw vrrp {vpn-common:rtg-vrrp}?
                    |     |        ...
                    |     +--rw service
                    |        ...
                    ...

                 Figure 18: BGP Routing Subtree Structure

   o  IS-IS: The model (Figure 19) allows the user to configure IS-IS to
      run on the 'vpn-network-access' interface.  An IS-IS instance can
      run L1, L2, or both levels.

                     ...
                     +--rw vpn-network-accesses
                     |  +--rw vpn-network-access* [id]
                     |     +--rw id
                     |     |       vpn-common:vpn-id
                     |     ...
                     |     +--rw ip-connection
                     |     |  ...
                     |     +--rw routing-protocols
                     |     |  +--rw routing-protocol* [id]
                     |     |     +--rw id                  string
                     |     |     +--rw type?
                     |     |     |        identityref
                     |     |     +--rw routing-profiles* [id]
                     |     |     |  +--rw id      leafref
                     |     |     |  +--rw type?   identityref
                     |     |     +--rw ospf {vpn-common:rtg-ospf}?
                     |     |     |  ...
                     |     |     +--rw bgp {vpn-common:rtg-bgp}?
                     |     |     |  ...
                     |     |     +--rw isis {vpn-common:rtg-isis}?
                     |     |     |  +--rw address-family*
                     |     |     |  |       vpn-common:address-family
                     |     |     |  +--rw area-address
                     |     |     |  |       yang:dotted-quad
                     |     |     |  +--rw level?            identityref



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                     |     |     |  +--rw metric?           uint16
                     |     |     |  +--rw process-id?       uint16
                     |     |     |  +--rw mode?             enumeration
                     |     |     |  +--rw status
                     |     |     |     +--rw admin-status
                     |     |     |     |  +--rw status?
                     |     |     |     |  |       identityref
                     |     |     |     |  +--rw last-updated?
                     |     |     |     |          yang:date-and-time
                     |     |     |     +--ro oper-status
                     |     |     |        +--ro status?
                     |     |     |        |       identityref
                     |     |     |        +--ro last-updated?
                     |     |     |                yang:date-and-time
                     |     |     +--rw static
                     |     |     |  ...
                     |     |     +--rw rip {vpn-common:rtg-rip}?
                     |     |     |  ...
                     |     |     +--rw vrrp {vpn-common:rtg-vrrp}?
                     |     |        ...
                     |     +--rw service
                     |        ...
                     ...

                Figure 19: IS-IS Routing Subtree Structure

   o  RIP: The module covers only a list of address-family as parameter.

   o  VRRP: The module covers only a list of address-family as
      parameter.

   The module allows a user to configure one or more IPv4 and/or IPv6
   static routes as depicted in Figure 20.


















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                       ...
                       +--rw vpn-network-accesses
                       |  +--rw vpn-network-access* [id]
                       |     +--rw id
                       |     |       vpn-common:vpn-id
                       |     ...
                       |     +--rw ip-connection
                       |     |  ...
                       |     +--rw routing-protocols
                       |     |  +--rw routing-protocol* [id]
                       |     |     +--rw id              string
                       |     |     +--rw type?      identityref
                       |     |     +--rw routing-profiles* [id]
                       |     |     |  +--rw id      leafref
                       |     |     |  +--rw type?   identityref
                       |     |     +--rw ospf {vpn-common:rtg-ospf}?
                       |     |     |  ...
                       |     |     +--rw bgp {vpn-common:rtg-bgp}?
                       |     |     |  ...
                       |     |     +--rw isis {vpn-common:rtg-isis}?
                       |     |     |  ...
                       |     |     +--rw static
                       |     |     |  +--rw cascaded-lan-prefixes
                       |     |     |     +--rw ipv4-lan-prefixes*
                       |     |     |     |       [lan next-hop]
                       |     |     |     |       {vpn-common:ipv4}?
                       |     |     |     |  +--rw lan
                       |     |     |     |  |       inet:ipv4-prefix
                       |     |     |     |  +--rw lan-tag?    string
                       |     |     |     |  +--rw next-hop
                       |     |     |     |          inet:ipv4-address
                       |     |     |     +--rw ipv6-lan-prefixes*
                       |     |     |             [lan next-hop]
                       |     |     |             {vpn-common:ipv6}?
                       |     |     |        +--rw lan
                       |     |     |        |       inet:ipv6-prefix
                       |     |     |        +--rw lan-tag?    string
                       |     |     |        +--rw next-hop
                       |     |     |                inet:ipv6-address
                       |     |     +--rw rip {vpn-common:rtg-rip}?
                       |     |     |  ...
                       |     |     +--rw vrrp {vpn-common:rtg-vrrp}?
                       |     |        ...
                       |     +--rw service
                       |        ...
                       ...

                Figure 20: Static Routing Subtree Structure



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7.3.4.2.5.  Services

   The 'services' container specifies the service parameters to apply
   for a given VPN network access (Figure 21).















































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                      ...
                      +--rw vpn-network-accesses
                      |  +--rw vpn-network-access* [id]
                      |     +--rw id
                      |     |       vpn-common:vpn-id
                      |     ...
                      |     +--rw service
                      |        +--rw svc-input-bandwidth     uint64
                      |        +--rw svc-output-bandwidth    uint64
                      |        +--rw svc-mtu                 uint16
                      |        +--rw qos {vpn-common:qos}?
                      |        |  +--rw qos-classification-policy
                      |        |  |  +--rw rule* [id]
                      |        |  |     +--rw id
                      |        |  |     |       string
                      |        |  |     +--rw (match-type)?
                      |        |  |     |  +--:(match-flow)
                      |        |  |     |  |  +--rw (l3)?
                      |        |  |     |  |  |  +--:(ipv4)
                      |        |  |     |  |  |  |  ...
                      |        |  |     |  |  |  +--:(ipv6)
                      |        |  |     |  |  |     ...
                      |        |  |     |  |  +--rw (l4)?
                      |        |  |     |  |     +--:(tcp)
                      |        |  |     |  |     |  ...
                      |        |  |     |  |     +--:(udp)
                      |        |  |     |  |        ...
                      |        |  |     |  +--:(match-application)
                      |        |  |     |     +--rw match-application?
                      |        |  |     |             identityref
                      |        |  |     +--rw target-class-id?
                      |        |  |             string
                      |        |  +--rw qos-profile
                      |        |     +--rw qos-profile* [profile]
                      |        |        +--rw profile      leafref
                      |        |        +--rw direction?   identityref
                      |        +--rw carrierscarrier
                      |        |       {vpn-common:carrierscarrier}?
                      |        |  +--rw signalling-type?   enumeration
                      |        +--rw multicast {vpn-common:multicast}?
                      |           +--rw site-type?        enumeration
                      |           +--rw address-family?
                      |           |       vpn-common:address-family
                      |           +--rw protocol-type?    enumeration
                      |           +--rw remote-source?    boolean
                      ...

                   Figure 21: Services Subtree Structure



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   The following attributes are defined:

   o  'svc-input-bandwidth': Indicates the inbound bandwidth of the
      connection (i.e., download bandwidth from the SP to the site).

   o  'svc-output-bandwidth': Indicates the outbound bandwidth of the
      connection (i.e., upload bandwidth from the site to the SP).

   o  'svc-mtu': Indicates the MTU at service level.  It can be the IP
      MTU or MPLS MTU, for example.

   o  'carrierscarrier': Groups a set of parameters that are used when
      CsC is enabled such the use of BGP for signalling purposes
      [RFC8277].

   o  'multicast': Specifies the multicast mode and other service-
      related attributes such as the address-family.

   o  'qos': Is used to define QoS policies to apply on a given
      connection.  Classification can be based on many criteria such as:

      *  Layer 3: As shown in Figure 23, the model allow to classify
         based on any IP header field or a combination thereof.  Both
         IPv4 and IPv6 are supported.

       +--rw qos {vpn-common:qos}?
       |  +--rw qos-classification-policy
       |  |  +--rw rule* [id]
       |  |     +--rw id
       |  |     |       string
       |  |     +--rw (match-type)?
       |  |     |  +--:(match-flow)
       |  |     |  |  +--rw (l3)?
       |  |     |  |  |  +--:(ipv4)
       |  |     |  |  |  |  ...
       |  |     |  |  |  +--:(ipv6)
       |  |     |  |  |     ...
       |  |     |  |  +--rw (l4)?
       |  |     |  |  +--rw (l3)?
       |  |     |  |  |  +--:(ipv4)
       |  |     |  |  |  |  +--rw ipv4
       |  |     |  |  |  |     +--rw dscp?
       |  |     |  |  |  |     |       inet:dscp
       |  |     |  |  |  |     +--rw ecn?
       |  |     |  |  |  |     |       uint8
       |  |     |  |  |  |     +--rw length?
       |  |     |  |  |  |     |       uint16
       |  |     |  |  |  |     +--rw ttl?



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       |  |     |  |  |  |     |       uint8
       |  |     |  |  |  |     +--rw protocol?
       |  |     |  |  |  |     |       uint8
       |  |     |  |  |  |     +--rw ihl?
       |  |     |  |  |  |     |       uint8
       |  |     |  |  |  |     +--rw flags?
       |  |     |  |  |  |     |       bits
       |  |     |  |  |  |     +--rw offset?
       |  |     |  |  |  |     |       uint16
       |  |     |  |  |  |     +--rw identification?
       |  |     |  |  |  |     |       uint16
       |  |     |  |  |  |     +--rw (destination-network)?
       |  |     |  |  |  |     |  +--:(destination-ipv4-network)
       |  |     |  |  |  |     |     +--rw destination-ipv4-network?
       |  |     |  |  |  |     |             inet:ipv4-prefix
       |  |     |  |  |  |     +--rw (source-network)?
       |  |     |  |  |  |        +--:(source-ipv4-network)
       |  |     |  |  |  |           +--rw source-ipv4-network?
       |  |     |  |  |  |  inet:ipv4-prefix
       |  |     |  |  |  +--:(ipv6)
       |  |     |  |  |     +--rw ipv6
       |  |     |  |  |        +--rw dscp?
       |  |     |  |  |        |       inet:dscp
       |  |     |  |  |        +--rw ecn?
       |  |     |  |  |        |       uint8
       |  |     |  |  |        +--rw length?
       |  |     |  |  |        |       uint16
       |  |     |  |  |        +--rw ttl?
       |  |     |  |  |        |       uint8
       |  |     |  |  |        +--rw protocol?
       |  |     |  |  |        |       uint8
       |  |     |  |  |        +--rw (destination-network)?
       |  |     |  |  |        |  +--:(destination-ipv6-network)
       |  |     |  |  |        |     +--rw destination-ipv6-network?
       |  |     |  |  |        |             inet:ipv6-prefix
       |  |     |  |  |        +--rw (source-network)?
       |  |     |  |  |        |  +--:(source-ipv6-network)
       |  |     |  |  |        |     +--rw source-ipv6-network?
       |  |     |  |  |        |             inet:ipv6-prefix
       |  |     |  |  |        +--rw flow-label?
       |  |     |  |  |                   inet:ipv6-flow-label
       |  |     |  |  +--rw (l4)?
       |  |     |  |     +--:(tcp)
       |  |     |  |     |  ...
       |  |     |  |     +--:(udp)
       |  |     |  |        ...
       ...




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                   Figure 22: QoS Subtree Structure (L3)

      *  Layer 4: As shown in Figure 23, TCP or UDP-related match
         crietria can be specified.

   +--rw qos {vpn-common:qos}?
   |  +--rw qos-classification-policy
   |  |  +--rw rule* [id]
   |  |     +--rw id
   |  |     |       string
   |  |     +--rw (match-type)?
   |  |     |  +--:(match-flow)
   |  |     |  |  +--rw (l3)?
   |  |     |  |  |  +--:(ipv4)
   |  |     |  |  |  |  ...
   |  |     |  |  |  +--:(ipv6)
   |  |     |  |  |     ...
   |  |     |  |  +--rw (l4)?
   |  |     |  |     +--:(tcp)
   |  |     |  |     |  +--rw tcp
   |  |     |  |     |     +--rw sequence-number?
   |  |     |  |     |     |       uint32
   |  |     |  |     |     +--rw acknowledgement-number?
   |  |     |  |     |     |       uint32
   |  |     |  |     |     +--rw data-offset?
   |  |     |  |     |     |       uint8
   |  |     |  |     |     +--rw reserved?
   |  |     |  |     |     |       uint8
   |  |     |  |     |     +--rw flags?
   |  |     |  |     |     |       bits
   |  |     |  |     |     +--rw window-size?
   |  |     |  |     |     |       uint16
   |  |     |  |     |     +--rw urgent-pointer?
   |  |     |  |     |     |       uint16
   |  |     |  |     |     +--rw options?
   |  |     |  |     |     |       binary
   |  |     |  |     |     +--rw (source-port)?
   |  |     |  |     |     |  +--:(source-port-range-or-operator)
   |  |     |  |     |     |     +--rw source-port-range-or-operator
   |  |     |  |     |     |        +--rw (port-range-or-operator)?
   |  |     |  |     |     |           +--:(range)
   |  |     |  |     |     |           |  +--rw lower-port
   |  |     |  |     |     |           |  |       inet:port-number
   |  |     |  |     |     |           |  +--rw upper-port
   |  |     |  |     |     |           |          inet:port-number
   |  |     |  |     |     |           +--:(operator)
   |  |     |  |     |     |              +--rw operator?
   |  |     |  |     |     |              |       operator



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   |  |     |  |     |     |              +--rw port
   |  |     |  |     |     |                      inet:port-number
   |  |     |  |     |     +--rw (destination-port)?
   |  |     |  |     +--:(destination-port-range-or-operator)
   |  |     |  |     |          +--rw destination-port-range-or-operator
   |  |     |  |     |             +--rw (port-range-or-operator)?
   |  |     |  |     |                +--:(range)
   |  |     |  |     |                |  +--rw lower-port
   |  |     |  |     |                |  |       inet:port-number
   |  |     |  |     |                |  +--rw upper-port
   |  |     |  |     |                |          inet:port-number
   |  |     |  |     |                +--:(operator)
   |  |     |  |     |                   +--rw operator?
   |  |     |  |     |                   |       operator
   |  |     |  |     |                   +--rw port
   |  |     |  |     |                           inet:port-number
   |  |     |  |     +--:(udp)
   |  |     |  |        +--rw udp
   |  |     |  |           +--rw length?
   |  |     |  |           |       uint16
   |  |     |  |           +--rw (source-port)?
   |  |     |  |           |  +--:(source-port-range-or-operator)
   |  |     |  |           |     +--rw source-port-range-or-operator
   |  |     |  |           |        +--rw (port-range-or-operator)?
   |  |     |  |           |           +--:(range)
   |  |     |  |           |           |  +--rw lower-port
   |  |     |  |           |           |  |       inet:port-number
   |  |     |  |           |           |  +--rw upper-port
   |  |     |  |           |           |          inet:port-number
   |  |     |  |           |           +--:(operator)
   |  |     |  |           |              +--rw operator?
   |  |     |  |           |              |       operator
   |  |     |  |           |              +--rw port
   |  |     |  |           |                      inet:port-number
   |  |     |  |           +--rw (destination-port)?
   |  |     |  |              +--:(destination-port-range-or-operator)
   |  |     |  |                +--rw destination-port-range-or-operator
   |  |     |  |                    +--rw (port-range-or-operator)?
   |  |     |  |                       +--:(range)
   |  |     |  |                       |  +--rw lower-port
   |  |     |  |                       |  |       inet:port-number
   |  |     |  |                       |  +--rw upper-port
   |  |     |  |                       |          inet:port-number
   |  |     |  |                       +--:(operator)
   |  |     |  |                          +--rw operator?
   |  |     |  |                          |       operator
   |  |     |  |                          +--rw port
   |  |     |  |                                  inet:port-number



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                    ...

                   Figure 23: QoS Subtree Structure (L4)

      *  Application match

7.3.4.3.  Multicast

   Multicast MAY be enabled for a particular vpn-network-node (see
   Figure 24).

   The model supports a single type of tree (Any-Source Multicast (ASM),
   Source-Specific Multicast (SSM), or bidirectional).

   When ASM is used, the model supports the configuration of rendez-vous
   points (RPs).  RP discovery may be 'static', 'bsr-rp', or 'auto-rp'.
   When set to 'static', RP to multicast grouping mapping MUST be
   configured as part of the 'rp-group-mappings' container.  The RP MAY
   be a provider node or a customer node.  When the RP is a customer
   node, the RP address must be configured using the 'rp-address' leaf
   otherwise no RP address is needed.

   The model supports RP redundancy through the 'rp-redundancy' leaf.
   How the redundancy is achieved is out of scope and is up to the
   implementation.

   When a particular VPN using ASM requires a more optimal traffic
   delivery, 'optimal-traffic-delivery' can be set.  When set to 'true',
   the implementation must use any mechanism to provide a more optimal
   traffic delivery for the customer.  Anycast is one of the mechanisms
   to enhance RPs redundancy, resilience against failures, and to
   recover from failures quickly.

   For redundancy purposes, Multicast Source Discovery Protocol (MSDP)
   [RFC3618] may be enabled and used to share the state about sources
   between multiple RPs.  The purpose of MSDP in this context is to
   enhance the robustness of the multicast service.  MSDP may be
   configured on Non-RP routers, which is useful in a domain that does
   not support multicast sources, but does support multicast transit.

                      ...
                      +--rw vpn-network-accesses
                      |  +--rw vpn-network-access* [id]
                      |     +--rw id
                      |     ..
                      +--rw multicast {vpn-common:multicast}?
                         +--rw enabled?       boolean
                         +--rw tree-flavor*   identityref



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                         +--rw rp
                         |  +--rw rp-group-mappings
                         |  |  +--rw rp-group-mapping* [id]
                         |  |     +--rw id                  uint16
                         |  |     +--rw provider-managed
                         |  |     |  +--rw enabled?
                         |  |     |  |       boolean
                         |  |     |  +--rw rp-redundancy?
                         |  |     |  |       boolean
                         |  |     |  +--rw optimal-traffic-delivery?
                         |  |     |  |       boolean
                         |  |     |  +--rw anycast
                         |  |     |     +--rw local-address?
                         |  |     |     |       inet:ip-address
                         |  |     |     +--rw rp-set-address*
                         |  |     |             inet:ip-address
                         |  |     +--rw rp-address
                         |  |     |       inet:ip-address
                         |  |     +--rw groups
                         |  |        +--rw group* [id]
                         |  |           +--rw id
                         |  |           |       uint16
                         |  |           +--rw (group-format)
                         |  |              +--:(group-prefix)
                         |  |              |  +--rw group-address?
                         |  |              |          inet:ip-prefix
                         |  |              +--:(startend)
                         |  |                 +--rw group-start?
                         |  |                 |       inet:ip-address
                         |  |                 +--rw group-end?
                         |  |                         inet:ip-address
                         |  +--rw rp-discovery
                         |     +--rw rp-discovery-type?   identityref
                         |     +--rw bsr-candidates
                         |        +--rw bsr-candidate-address*
                         |                inet:ip-address
                         +--rw msdp {msdp}?
                            +--rw enabled?         boolean
                            +--rw peer?            inet:ip-address
                            +--rw local-address?   inet:ip-address

                  Figure 24: Multicast Subtree Structure

8.  Layer 3 Network Model

   This module uses types defined in [RFC6991] and groupings defined in
   [RFC8519].




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<CODE BEGINS>  file "ietf-l3vpn-ntw@2020-10-16.yang"
module ietf-l3vpn-ntw {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-l3vpn-ntw";
  prefix l3nm;

  import ietf-vpn-common {
    prefix vpn-common;
    reference
      "RFC UUUU: A Layer 2/3 VPN Common YANG Model";
  }
  import ietf-inet-types {
    prefix inet;
    reference
      "Section 4 of RFC 6991";
  }
  import ietf-yang-types {
    prefix yang;
    reference
      "Section 3 of RFC 6991";
  }
  import ietf-packet-fields {
    prefix pf;
    reference
      "RFC 8519: YANG Data Model for Network Access
                 Control Lists (ACLs)";
  }

  organization
    "IETF OPSA (Operations and Management Area) Working Group ";
  contact
    "WG Web:   <http://tools.ietf.org/wg/opsawg/>
     WG List:  <mailto:opsawg@ietf.org>
     Editor:   Samier Barguil
               <mailto:samier.barguilgiraldo.ext@telefonica.com>
     Editor:   Oscar Gonzalez de Dios
               <mailto:oscar.gonzalezdedios@telefonica.com>
     Editor:   Mohamed Boucadair
              <mailto:mohamed.boucadair@orange.com>
     Author:   Luis Angel Munoz
               <mailto:luis-angel.munoz@vodafone.com>
     Author:   Alejandro Aguado
               <mailto:alejandro.aguado_martin@nokia.com>
    ";
  description
    "This YANG module defines a generic network-oriented model
     for the configuration of Layer 3 Virtual Private Networks.




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     Copyright (c) 2020 IETF Trust and the persons identified as
     authors of the code.  All rights reserved.

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

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

  revision 2020-10-16 {
    description
      "Initial revision.";
    reference
      "RFC XXXX: A Layer 3 VPN Network YANG Model";
  }

  /* Features */

  feature msdp {
    description
      "This feature indicates that Multicast Source
       Discovery Protocol (MSDP) capabilities are
       supported by the VPN.";
    reference
      "RFC 3618: Multicast Source Discovery Protocol (MSDP)";
  }

  /* Typedefs */

  typedef area-address {
    type string {
      pattern '[0-9A-Fa-f]{2}(\.[0-9A-Fa-f]{4}){0,6}';
    }
    description
      "This type defines the area address format.";
  }

  /* Identities */

  identity address-allocation-type {
    description
      "Base identity for address-allocation-type for
       PE-CE link.";



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  }

  identity provider-dhcp {
    base address-allocation-type;
    description
      "The Provider's network provides a DHCP service
       to the customer.";
  }

  identity provider-dhcp-relay {
    base address-allocation-type;
    description
      "The Provider's network provides a DHCP relay service
       to the customer.";
  }

  identity provider-dhcp-slaac {
    base address-allocation-type;
    description
      "The Provider's network provides a DHCP service to
       the customer, as well as IPv6 Stateless Address
       Autoconfiguration (SLAAC).";
    reference
      "RFC 7527: IPv6 Stateless Address Autoconfiguration";
  }

  identity static-address {
    base address-allocation-type;
    description
      "The Provider-to-customer addressing is static.";
  }

  identity slaac {
    base address-allocation-type;
    description
      "Use IPv6 SLAAC.";
    reference
      "RFC 7527: IPv6 Stateless Address Autoconfiguration";
  }

  identity isis-level {
    description
      "Defines the IS-IS level for interface
       and system.";
  }

  identity level1 {
    base isis-level;



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    description
      "IS-IS level 1.";
  }

  identity level2 {
    base isis-level;
    description
      "IS-IS level 2.";
  }

  identity level1-2 {
    base isis-level;
    description
      "IS-IS levels 1 and 2.";
  }

  identity bearer-inf-type {
    description
      "Identity for the bearer interface type.";
  }

  identity port-id {
    base bearer-inf-type;
    description
      "Identity for the priority-tagged interface.";
  }

  identity lag-id {
    base bearer-inf-type;
    description
      "Identity for the lag-tagged interface.";
  }

  /* Groupings */

  grouping security-params {
    container security {
      leaf auth-key {
        type string;
        description
          "MD5 authentication password for the connection
           towards the customer edge.";
      }
      description
        "Container for aggregating any security parameter
          for routing sessions between a PE and a CE.";
    }
    description



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      "Grouping to define a set of security parameters";
  }

  grouping ports {
    choice source-port {
      container source-port-range-or-operator {
        uses pf:port-range-or-operator;
        description
          "Source port definition.";
      }
      description
        "Choice of specifying the source port or
          referring to a group of source port numbers.";
    }
    choice destination-port {
      container destination-port-range-or-operator {
        uses pf:port-range-or-operator;
        description
          "Destination port definition.";
      }
      description
        "Choice of specifying a destination port or
         referring to a group of destination port
         numbers.";
    }
    description
      "Choice of specifying a source or destination
       port numbers.";
  }

  /* Main Blocks */
  /* Main l3nm */

  container l3vpn-ntw {
    container vpn-profiles {
      uses vpn-common:vpn-profile-cfg;
      description
        "Contains a set of valid VPN Profiles to
         reference in the VPN service.";
    }
    container vpn-services {
      list vpn-service {
        key "vpn-id";
        uses vpn-common:service-status;
        uses vpn-common:vpn-description;
        leaf l3sm-vpn-id {
          type vpn-common:vpn-id;
          description



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            "Pointer to the parent L3SM service,
             if any.";
        }
        leaf vpn-type {
          type identityref {
            base vpn-common:vpn-signaling-type;
          }
          description
            "Indicates the service type";
        }
        leaf vpn-service-topology {
          type identityref {
            base vpn-common:vpn-topology;
          }
          default "vpn-common:any-to-any";
          description
            "VPN service topology.";
        }
        container ie-profiles {
          list ie-profile {
            key "ie-profile-id";
            leaf ie-profile-id {
              type string;
              description
                "IE profile id.";
            }
            uses vpn-common:rt-rd;
            description
              "List for Imort/Export profile.";
          }
          description
            "Container for Import/Export profiles.";
        }
        uses vpn-common:svc-transport-encapsulation;
        container vpn-nodes {
          description
            "Container for VPN nodes.";
          list vpn-node {
            key "vpn-node-id";
            leaf vpn-node-id {
              type union {
                type vpn-common:vpn-id;
                type uint32;
              }
              description
                "Type STRING or NUMBER Service-Id.";
            }
            leaf local-autonomous-system {



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              type inet:as-number;
              description
                "Provider's AS number in case the customer
                 requests BGP routing.";
            }
            leaf description {
              type string;
              description
                "Textual description of the VPN node.";
            }
            leaf ne-id {
              type string;
              description
                "Unique identifier of the network element
                 where the VPN node is deployed.";
            }
            leaf router-id {
              type inet:ip-address;
              description
                "The router-id information can be an IPv4
                 or IPv6 address.";
            }
            leaf address-family {
              type vpn-common:address-family;
              description
                "The address family used for router-id
                 information.";
            }
            leaf node-role {
              type identityref {
                base vpn-common:role;
              }
              default "vpn-common:any-to-any-role";
              description
                "Role of the VPN node in the IP VPN.";
            }
            uses vpn-common:rt-rd;
            uses vpn-common:service-status;
            leaf node-ie-profile {
              type leafref {
                path "/l3vpn-ntw/vpn-services/"
                   + "vpn-service/ie-profiles/"
                   + "ie-profile/ie-profile-id";
              }
              description
                "Node's Import/Export profile.";
            }
            uses vpn-common:vpn-node-group;



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            container vpn-network-accesses {
              list vpn-network-access {
                key "id";
                leaf id {
                  type vpn-common:vpn-id;
                  description
                    "Identifier for the access.";
                }
                leaf port-id {
                  type vpn-common:vpn-id;
                  description
                    "Identifier for the network access.";
                }
                leaf description {
                  type string;
                  description
                    "Textual description of a network access.";
                }
                uses vpn-common:service-status;
                leaf vpn-network-access-type {
                  type identityref {
                    base vpn-common:site-network-access-type;
                  }
                  default "vpn-common:point-to-point";
                  description
                    "Describes the type of connection, e.g.,
                     point-to-point or multipoint.";
                }
                container connection {
                  leaf encapsulation-type {
                    type identityref {
                      base vpn-common:encapsulation-type;
                    }
                    default "vpn-common:untagged-int";
                    description
                      "Encapsulation type.  By default,
                       the encapsulation type is set to
                       'untagged'.";
                  }
                  container logical-interface {
                    leaf peer-reference {
                      type uint32;
                      description
                        "Specify the associated logical peer
                         interface";
                    }
                    description
                      "Reference of a logical interface



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                       type.";
                  }
                  container tagged-interface {
                    leaf type {
                      type identityref {
                        base vpn-common:encapsulation-type;
                      }
                      default "vpn-common:priority-tagged";
                      description
                        "Tagged interface type.  By default,
                         the type of the tagged interface is
                         'priority-tagged'.";
                    }
                    container dot1q-vlan-tagged {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:dot1q')" {
                        description
                          "Only applies when the type of the
                           tagged interface is 'dot1q'.";
                      }
                      if-feature "vpn-common:dot1q";
                      leaf tag-type {
                        type identityref {
                          base vpn-common:tag-type;
                        }
                        default "vpn-common:c-vlan";
                        description
                          "Tag type.  By default, the tag
                           type is 'c-vlan'.";
                      }
                      leaf cvlan-id {
                        type uint16;
                        description
                          "VLAN identifier.";
                      }
                      description
                        "Tagged interface.";
                    }
                    container priority-tagged {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:priority-tagged')" {
                        description
                          "Only applies when the type of the
                           tagged interface is
                           'priority-tagged'.";
                      }
                      leaf tag-type {
                        type identityref {



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                          base vpn-common:tag-type;
                        }
                        default "vpn-common:c-vlan";
                        description
                          "Tag type.  By default, the tag
                           type is 'c-vlan'.";
                      }
                      description
                        "Priority tagged.";
                    }
                    container qinq {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:qinq')" {
                        description
                          "Only applies when the type of
                           the tagged interface is 'qinq'.";
                      }
                      if-feature "vpn-common:qinq";
                      leaf tag-type {
                        type identityref {
                          base vpn-common:tag-type;
                        }
                        default "vpn-common:c-s-vlan";
                        description
                          "Tag type.  By default, the tag
                           type is 'c-s-vlan'.";
                      }
                      leaf svlan-id {
                        type uint16;
                        mandatory true;
                        description
                          "SVLAN identifier.";
                      }
                      leaf cvlan-id {
                        type uint16;
                        mandatory true;
                        description
                          "CVLAN identifier.";
                      }
                      description
                        "QinQ.";
                    }
                    container qinany {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:qinany')" {
                        description
                          "Only applies when the type of the
                           tagged interface is 'qinany'.";



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                      }
                      if-feature "vpn-common:qinany";
                      leaf tag-type {
                        type identityref {
                          base vpn-common:tag-type;
                        }
                        default "vpn-common:s-vlan";
                        description
                          "Tag type.  By default, the tag type
                           is 's-vlan'.";
                      }
                      leaf svlan-id {
                        type uint16;
                        mandatory true;
                        description
                          "Service VLAN ID.";
                      }
                      description
                        "Container for QinAny.";
                    }
                    container vxlan {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:vxlan')" {
                        description
                          "Only applies when the type of the
                           tagged interface is 'vxlan'.";
                      }
                      if-feature "vpn-common:vxlan";
                      leaf vni-id {
                        type uint32;
                        mandatory true;
                        description
                          "VXLAN Network Identifier (VNI).";
                      }
                      leaf peer-mode {
                        type identityref {
                          base vpn-common:vxlan-peer-mode;
                        }
                        default "vpn-common:static-mode";
                        description
                          "Specifies the VXLAN access mode.
                           By default, the peer mode is set
                           to 'static-mode'.";
                      }
                      list peer-list {
                        key "peer-ip";
                        leaf peer-ip {
                          type inet:ip-address;



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                          description
                            "Peer IP.";
                        }
                        description
                          "List of peer IP addresses.";
                      }
                      description
                        "QinQ.";
                    }
                    description
                      "Container for tagged interfaces.";
                  }
                  container bearer {
                    leaf bearer-reference {
                      if-feature "vpn-common:bearer-reference";
                      type string;
                      description
                        "This is an internal reference for*
                         the SP.";
                    }
                    container pseudowire {
                      leaf vcid {
                        type uint32;
                        description
                          "PW or VC identifier.";
                      }
                      leaf far-end {
                        type union {
                          type uint32;
                          type inet:ipv4-address;
                        }
                        description
                          "SDP/Far End/LDP neighbour reference.";
                      }
                      description
                        "Pseudowire termination parameters";
                    }
                    container vpls {
                      leaf vcid {
                        type union {
                          type uint32;
                          type string;
                        }
                        description
                          "VCID identifier, IRB/RVPPLs interface
                           supported using string
                           format.";
                      }



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                      leaf far-end {
                        type union {
                          type uint32;
                          type inet:ipv4-address;
                        }
                        description
                          "SDP/Far End/LDP Neighbour reference.";
                      }
                      description
                        "Pseudowire termination parameters";
                    }
                    description
                      "Defines physical properties of a site
                       attachment.";
                  }
                  description
                    "Encapsulation types";
                }
                container ip-connection {
                  container ipv4 {
                    if-feature "vpn-common:ipv4";
                    leaf address-allocation-type {
                      type identityref {
                        base address-allocation-type;
                      }
                      must "not(derived-from-or-self(current(), "
                        + "'slaac') or derived-from-or-self(current(),"
                        + " 'provider-dhcp-slaac'))" {
                        error-message "SLAAC is only applicable to
                                     IPv6";
                      }
                      description
                        "Defines how addresses are allocated.
                         If there is no value for the address
                         allocation type, then IPv4 is not enabled.";
                    }
                    choice allocation-type {
                      case provider-dhcp {
                        when "derived-from-or-self(./address-"
                           + "allocation-type, 'provider-dhcp')" {
                          description
                            "Only applies when addresses are
                             allocated by DHCP.";
                        }
                        leaf provider-address {
                          type inet:ipv4-address;
                          description
                            "Address of provider side.



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                             If provider-address is not specified,
                             then prefix length should not be
                             specified either.

                             It also implies provider-dhcp
                             allocation is not enabled.

                             If provider-address is specified,
                             then the prefix length may or
                             may not be specified.";
                        }
                        leaf prefix-length {
                          type uint8 {
                            range "0..32";
                          }
                          must '(../provider-address)' {
                            error-message
                              "If the prefix length is specified,
                               provider-address must also be
                               specified.";
                            description
                              "If the prefix length is specified,
                               provider-address must also be
                               specified.";
                          }
                          description
                            "Subnet prefix length expressed in bits.
                             If not specified, or specified as zero,
                             this means the customer leaves the actual
                             prefix length value to the provider.";
                        }
                        choice address-assign {
                          default "number";
                          case number {
                            leaf number-of-dynamic-address {
                              type uint16;
                              default "1";
                              description
                                "Describes the number of IP
                                 addresses the customer requires.";
                            }
                          }
                          case explicit {
                            container customer-addresses {
                              list address-group {
                                key "group-id";
                                leaf group-id {
                                  type string;



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                                  description
                                    "Group-id for the address range
                                     from start-address to
                                     end-address.";
                                }
                                leaf start-address {
                                  type inet:ipv4-address;
                                  description
                                    "First address.";
                                }
                                leaf end-address {
                                  type inet:ipv4-address;
                                  description
                                    "Last address.";
                                }
                                description
                                  "Describes IP addresses allocated by
                                   DHCP.

                                   When only start-address or only
                                   end-address is present, it
                                   represents a single address.
                                   When both start-address and
                                   end-address are specified, it
                                   implies a range inclusive of
                                   both addresses.  If no address
                                   is specified, it implies customer
                                   addresses group is not supported.";
                              }
                              description
                                "Container for customer addresses is
                                 allocated by DHCP.";
                            }
                          }
                          description
                            "Choice for the way to assign
                             addresses.";
                        }
                        description
                          "DHCP allocated addresses related
                           parameters.";
                      }
                      case dhcp-relay {
                        when "derived-from-or-self(./address-allocation"
                           + "-type, 'provider-dhcp-relay')" {
                          description
                            "Only applies when provider is required to
                             implement DHCP relay function.";



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                        }
                        leaf dr-provider-address {
                          type inet:ipv4-address;
                          description
                            "Address of provider side.

                             If provider-address is
                             not specified, then prefix length
                             should not be specified either.

                             It also implies provider-dhcp
                             allocation is not enabled.

                             If provider-address is specified,
                             then prefix length may or may
                             not be specified.";
                        }
                        leaf dr-prefix-length {
                          type uint8 {
                            range "0..32";
                          }
                          must '(../dr-provider-address)' {
                            error-message
                              "If prefix length is specified,
                               provider-address must also be
                               specified.";
                            description
                              "If prefix length is specified,
                               provider-address must also be
                               specified.";
                          }
                          description
                            "Subnet prefix length expressed in bits.

                             If not specified, or specified as zero,
                             this means the customer leaves the
                             actual prefix  length value
                             to the provider.";
                        }
                        container customer-dhcp-servers {
                          leaf-list server-ip-address {
                            type inet:ipv4-address;
                            description
                              "IP address of customer DHCP
                               server.";
                          }
                          description
                            "Container for list of customer



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                             DHCP servers.";
                        }
                        description
                          "DHCP relay provided by operator.";
                      }
                      case static-addresses {
                        when "derived-from-or-self(./address-allocation"
                           + "-type, 'static-address')" {
                          description
                            "Only applies when address allocation
                            type is static.";
                        }
                        leaf primary-address {
                          type leafref {
                            path "../address/address-id";
                          }
                          description
                            "Principal address of the connection.";
                        }
                        list address {
                          key "address-id";
                          leaf address-id {
                            type string;
                            description
                              "IPv4 Address";
                          }
                          leaf s-provider-address {
                            type inet:ipv4-address;
                            description
                              "IPv4 Address List of the provider side.
                               When the protocol allocation type is
                               static, the provider address must be
                               configured.";
                          }
                          leaf s-customer-address {
                            type inet:ipv4-address;
                            description
                              "IPv4 Address of customer side.";
                          }
                          leaf s-prefix-length {
                            type uint8 {
                              range "0..32";
                            }
                            description
                              "Subnet prefix length expressed
                               in bits. It is applied to both
                               provider-address and customer-address.";
                          }



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                          description
                            "Describes IPv4 addresses used.";
                        }
                        description
                          "Describes IPv4 addresses used.";
                      }
                      description
                        "Choice the address allocation.";
                    }
                    description
                      "IPv4-specific parameters.";
                  }
                  container ipv6 {
                    if-feature "vpn-common:ipv6";
                    leaf address-allocation-type {
                      type identityref {
                        base address-allocation-type;
                      }
                      description
                        "Defines how addresses are allocated.
                         If there is no value for the address
                         allocation type, then IPv6 is
                         not enabled.";
                    }
                    choice allocation-type {
                      choice provider-dhcp {
                        when "derived-from-or-self(./address-allo"
                           + "cation-type, 'provider-dhcp') "
                           + "or derived-from-or-self(./address-allo"
                           + "cation-type, 'provider-dhcp-slaac')" {
                          description
                            "Only applies when addresses are
                             allocated by DHCP.";
                        }
                        leaf provider-address {
                          type inet:ipv6-address;
                          description
                            "Address of the provider side.

                             If provider-address is not specified,
                             then prefix length should not be
                             specified either.  It also implies
                             provider-dhcp allocation is not
                             enabled.

                             If provider-address is
                             specified, then prefix length may
                             or may not be specified.";



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                        }
                        leaf prefix-length {
                          type uint8 {
                            range "0..128";
                          }
                          must '(../provider-address)' {
                            error-message
                              "If prefix length is specified,
                               provider-address
                               must also be specified.";
                            description
                              "If prefix length is specified,
                                provider-address
                               must also be specified.";
                          }
                          description
                            "Subnet prefix length expressed in
                             bits.

                             If not specified, or specified as
                             zero, this means the customer leaves
                             the actual prefix length value to
                             the provider.";
                        }
                        choice address-assign {
                          default "number";
                          case number {
                            leaf number-of-dynamic-address {
                              type uint16;
                              default "1";
                              description
                                "Describes the number of IP
                                 addresses required by the
                                 customer.";
                            }
                          }
                          case explicit {
                            container customer-addresses {
                              list address-group {
                                key "group-id";
                                leaf group-id {
                                  type string;
                                  description
                                    "Group-id for the address range
                                     from start-address to
                                     end-address.";
                                }
                                leaf start-address {



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                                  type inet:ipv6-address;
                                  description
                                    "First address.";
                                }
                                leaf end-address {
                                  type inet:ipv6-address;
                                  description
                                    "Last address.";
                                }
                                description
                                  "Describes IP addresses allocated
                                   by DHCP.

                                   When only start-address or only
                                   end-address is present, it
                                   represents a single address.

                                   When both start-address and
                                   end-address are specified, it
                                   implies a range inclusive of
                                   both addresses.

                                   If no address is specified, it
                                   implies customer addresses group
                                   is not supported.";
                              }
                              description
                                "Container for customer addresses
                                 allocated by DHCP.";
                            }
                          }
                          description
                            "Choice for the way to assign addresses.";
                        }
                        description
                          "DHCP allocated addresses related
                           parameters.";
                      }
                      case dhcp-relay {
                        when "derived-from-or-self(./address-allo"
                           + "cation-type, 'provider-dhcp-relay')" {
                          description
                            "Only applies when the provider is required
                             to implement DHCP relay function.";
                        }
                        leaf dr-provider-address {
                          type inet:ipv6-address;
                          description



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                            "Address of the provider side.

                             If provider-address is not specified,
                             then prefix length should not be
                             specified either.  It also implies
                             provider-dhcp allocation is not enabled.

                             If provider address is specified, then
                             prefix length may or may not be
                             specified.";
                        }
                        leaf dr-prefix-length {
                          type uint8 {
                            range "0..128";
                          }
                          must '(../dr-provider-address)' {
                            error-message
                              "If prefix length is specified,
                               provider-address must also be
                               specified.";
                            description
                              "If prefix length is specified,
                               provider-address must also be
                               specified.";
                          }
                          description
                            "Subnet prefix length expressed in bits.

                             If not specified, or specified as zero,
                             this means the customer leaves the
                             actual prefix length value to the
                             provider.";
                        }
                        container customer-dhcp-servers {
                          leaf-list server-ip-address {
                            type inet:ipv6-address;
                            description
                              "This node contains the IP address of
                               the customer DHCP server.  If the DHCP
                               relay function is implemented by the
                               provider, this node contains the
                               configured value.";
                          }
                          description
                            "Container for list of customer DHCP
                             servers.";
                        }
                        description



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                          "DHCP relay provided by operator.";
                      }
                      case static-addresses {
                        when "derived-from-or-self(./address-allocation"
                           + "-type, 'static-address')" {
                          description
                            "Only applies when protocol allocation type
                             is static.";
                        }
                        leaf s-primary-address {
                          type leafref {
                            path "../s-address/address-id";
                          }
                          description
                            "Principal address of the connection";
                        }
                        list s-address {
                          key "address-id";
                          leaf address-id {
                            type string;
                            description
                              "IPv4 Address";
                          }
                          leaf provider-address {
                            type inet:ipv6-address;
                            description
                              "IPv6 Address of the provider side.  When
                               the protocol allocation type is static,
                               the provider address must be
                               configured.";
                          }
                          leaf customer-address {
                            type inet:ipv6-address;
                            description
                              "The IPv6 Address of the customer side.";
                          }
                          leaf prefix-length {
                            type uint8 {
                              range "0..128";
                            }
                            description
                              "Subnet prefix length expressed in bits.
                               It is applied to both provider-address
                               and customer-address.";
                          }
                          description
                            "Describes IPv6 addresses used.";
                        }



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                        description
                          "IPv6-specific parameters.";
                      }
                      description
                        "IPv6 allocation type.";
                    }
                    description
                      "IPv6-specific parameters.";
                  }
                  container oam {
                    container bfd {
                      if-feature "vpn-common:bfd";
                      leaf enabled {
                        type boolean;
                        default "false";
                        description
                          "If true, BFD activation is required.";
                      }
                      choice holdtime {
                        default "fixed";
                        case fixed {
                          leaf fixed-value {
                            type uint32;
                            units "msec";
                            description
                              "Expected BFD holdtime.

                               The customer may impose some fixed
                               values for the holdtime period if the
                               provider allows the customer use this
                               function.

                               If the provider doesn't allow the
                               customer to use this function,
                               the fixed-value will not be set.";
                          }
                        }
                        case profile {
                          leaf profile-name {
                            type leafref {
                              path "/l3vpn-ntw/vpn-profiles/"
                                 + "valid-provider-identifiers/"
                                 + "bfd-profile-identifier/id";
                            }
                            description
                              "Well-known SP profile name.

                               The provider can propose some profiles



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                               to the customer, depending on the
                               service level the customer wants to
                               achieve.

                               Profile names must be communicated to
                               the customer.";
                          }
                          description
                            "Well-known SP profile.";
                        }
                        description
                          "Choice for holdtime flavor.";
                      }
                      description
                        "Container for BFD.";
                    }
                    description
                      "Defines the Operations, Administration,
                       and Maintenance (OAM)mechanisms used on
                       the connection.

                       BFD is set as a fault detection mechanism,
                       but the 'oam' container can easily
                       be augmented by other mechanisms";
                  }
                  description
                    "Defines connection parameters.";
                }
                container security {
                  container encryption {
                    if-feature "vpn-common:encryption";
                    leaf enabled {
                      type boolean;
                      default "false";
                      description
                        "If true, traffic encryption on the
                         connection is required. It is
                         disabled, otherwise.";
                    }
                    leaf layer {
                      when "../enabled = 'true'" {
                        description
                          "Require a value for layer when
                           enabled is true.";
                      }
                      type enumeration {
                        enum layer2 {
                          description



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                            "Encryption will occur at Layer 2.";
                        }
                        enum layer3 {
                          description
                            "Encryption will occur at Layer 3.
                             For example, IPsec may be used when
                             a customer requests Layer 3
                             encryption.";
                        }
                      }
                      description
                        "Layer on which encryption is applied.";
                    }
                    description
                      "Container for CE-PE security encryption.";
                  }
                  container encryption-profile {
                    choice profile {
                      case provider-profile {
                        leaf profile-name {
                          type leafref {
                            path "/l3vpn-ntw/vpn-profiles"
                               + "/valid-provider-identifiers"
                               + "/encryption-profile-identifier/id";
                          }
                          description
                            "Name of the SP profile to be applied.";
                        }
                      }
                      case customer-profile {
                        leaf algorithm {
                          type string;
                          description
                            "Encryption algorithm to be used.";
                        }
                      }
                      description
                        "Choice for encryption profile.";
                    }
                    choice key-type {
                      default "psk";
                      case psk {
                        leaf preshared-key {
                          type string;
                          description
                            "Pre-Shared Key (PSK) coming from the
                             customer.";
                        }



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                      }
                      description
                        "Choice of encryption profile.
                         The encryption profile can be the
                         provider profile or customer profile.";
                    }
                    description
                      "Container for encryption profile.";
                  }
                  description
                    "Site-specific security parameters.";
                }
                container routing-protocols {
                  list routing-protocol {
                    key "id";
                    leaf id {
                      type string;
                      description
                        "Unique identifier for routing protocol.";
                    }
                    leaf type {
                      type identityref {
                        base vpn-common:routing-protocol-type;
                      }
                      description
                        "Type of routing protocol.";
                    }
                    list routing-profiles {
                      key "id";
                      leaf id {
                        type leafref {
                          path "/l3vpn-ntw/vpn-profiles"
                             + "/valid-provider-identifiers"
                             + "/routing-profile-identifier/id";
                        }
                        description
                          "Routing profile to be used.";
                      }
                      leaf type {
                        type identityref {
                          base vpn-common:ie-type;
                        }
                        description
                          "Import, export or both.";
                      }
                      description
                        "Routing profiles.";
                    }



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                    container ospf {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:ospf')" {
                        description
                          "Only applies when protocol is OSPF.";
                      }
                      if-feature "vpn-common:rtg-ospf";
                      leaf-list address-family {
                        type vpn-common:address-family;
                        min-elements 1;
                        description
                          "If OSPF is used on this site, this node
                           contains a configured value.  This node
                           contains at least one address family
                           to be activated.";
                      }
                      leaf area-address {
                        type yang:dotted-quad;
                        mandatory true;
                        description
                          "Area address.";
                      }
                      leaf metric {
                        type uint16;
                        default "1";
                        description
                          "Metric of the PE-CE link.  It is used
                           in the routing state calculation and
                           path selection.";
                      }
                      leaf mtu {
                        type uint16;
                        description
                          "Maximum transmission unit for a given
                           OSPF link.";
                      }
                      leaf process-id {
                        type uint16;
                        description
                          "Process id of the OSPF CE-PE connection.";
                      }
                      uses security-params;
                      container sham-links {
                        if-feature "vpn-common:rtg-ospf-sham-link";
                        list sham-link {
                          key "target-site";
                          leaf target-site {
                            type vpn-common:vpn-id;



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                            description
                              "Target site for the sham link connection.
                               The site is referred to by its ID.";
                          }
                          leaf metric {
                            type uint16;
                            default "1";
                            description
                              "Metric of the sham link.  It is used in
                               the routing state calculation and path
                               selection.  The default value is set
                               to 1.";
                          }
                          description
                            "Creates a sham link with another site.";
                        }
                        description
                          "List of sham links.";
                      }
                      description
                        "OSPF-specific configuration.";
                    }
                    container bgp {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:bgp')" {
                        description
                          "Only applies when protocol is BGP.";
                      }
                      if-feature "vpn-common:rtg-bgp";
                      leaf peer-autonomous-system {
                        type inet:as-number;
                        mandatory true;
                        description
                          "Indicates the Customer's AS Number (ASN) in
                           case the Customer requests BGP routing.";
                      }
                      leaf local-autonomous-system {
                        type inet:as-number;
                        description
                          "Is set to the ASN to override a peers' ASN
                           if such feature is requested by the
                           Customer.";
                      }
                      leaf-list address-family {
                        type vpn-common:address-family;
                        min-elements 1;
                        description
                          "This node contains at least one



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                           address-family to be activated.";
                      }
                      leaf-list neighbor {
                        type inet:ip-address;
                        description
                          "IP address(es) of the BGP neighbor. IPv4
                           and IPv6 neighbors may be indicated if
                           two sessions will be used for IPv4 and
                           IPv6.";
                      }
                      leaf multihop {
                        type uint8;
                        description
                          "Describes the number of IP hops allowed
                           between a given BGP neighbor and the PE.";
                      }
                      uses security-params;
                      uses vpn-common:service-status;
                      leaf description {
                        type string;
                        description
                          "Includes a description of the BGP session.
                           Such description is meant to be used for
                           diagnosis purposes. The semantic of the
                           description is local to an
                           implementation.";
                      }
                      leaf as-override {
                        type boolean;
                        default "false";
                        description
                          "Defines whether AS override is enabled,
                           i.e., replace the ASN of the peer specified
                           in the AS Path attribute with the local
                           AS number.";
                      }
                      leaf default-route {
                        type boolean;
                        default "false";
                        description
                          "Defines whether default route(s) can be
                           advertised to its peer. If set, the
                           default route(s) is advertised to its
                           peer.";
                      }
                      container bgp-max-prefix {
                        leaf max-prefix {
                          type uint32;



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                          default "5000";
                          description
                            "Indicates the maximimum number of BGP
                             prefixes allowed in the BGP session.

                             It allows to control how many prefixes
                             can be received from a neighbor.

                             If the limit is exceeded, the session
                              can be teared down.";
                          reference
                            "RFC4271, Section 8.2.2.";
                        }
                        leaf warning-threshold {
                          type decimal64 {
                            fraction-digits 5;
                            range "0..100";
                          }
                          units "percent";
                          default "75";
                          description
                            "When this value is reached, a warning
                             notification will be triggered.";
                        }
                        leaf violate-action {
                          type enumeration {
                            enum warning {
                              description
                                "Only a warning message is sent to
                                 the peer when the limit is
                                 exceeded.";
                            }
                            enum discard-extra-paths {
                              description
                                "Discards extra paths when the
                                 limit is exceeded.";
                            }
                            enum restart {
                              description
                                "Restart after a time interval.";
                            }
                          }
                          description
                            "BGP neighbour max-prefix violate
                             action";
                        }
                        leaf restart-interval {
                          type uint16;



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                          units "minutes";
                          description
                            "Time interval (min) after which the
                             BGP session will be reestablished.";
                        }
                        description
                          "Controls the behavior when a prefix
                           maximum is reached.";
                      }
                      container bgp-timer {
                        description
                          "Includes two BGP timers that can be
                           customized when building a VPN service
                           with BGP used as CE-PE routing
                           protocol.";
                        leaf keep-alive {
                          type uint16 {
                            range "0..21845";
                          }
                          units "seconds";
                          default "30";
                          description
                            "This timer indicates the KEEPALIVE
                             messages'  frequency between a PE
                             and a BGP peer.

                             If set to '0', it indicates KEEPALIVE
                             messages are disabled.

                             It is suggested that the maximum time
                             between  KEEPALIVEmessages would be
                             one third of the Hold Time interval.";
                          reference
                            "Section 4.4 of RFC 4271";
                        }
                        leaf hold-time {
                          type uint16 {
                            range "0 | 3..65535";
                          }
                          units "seconds";
                          default "90";
                          description
                            "It indicates the maximum number of
                            seconds that may elapse between the
                            receipt of successive KEEPALIVE
                            and/or UPDATE   messages from the peer.

                            The Hold Time must be either zero or



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                            at least three seconds.";
                          reference
                            "Section 4.2 of RFC 4271";
                        }
                      }
                      description
                        "BGP-specific configuration.";
                    }
                    container isis {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:isis')" {
                        description
                          "Only applies when protocol is IS-IS.";
                      }
                      if-feature "vpn-common:rtg-isis";
                      leaf-list address-family {
                        type vpn-common:address-family;
                        min-elements 1;
                        description
                          "If ISIS is used on this site, this node
                           contains a configured value.  This node
                           contains at least one address family
                           to be activated.";
                      }
                      leaf area-address {
                        type yang:dotted-quad;
                        mandatory true;
                        description
                          "Area address.";
                      }
                      leaf level {
                        type identityref {
                          base isis-level;
                        }
                        description
                          "level1, level2 or level1-2";
                      }
                      leaf metric {
                        type uint16;
                        default "1";
                        description
                          "Metric of the PE-CE link.  It is used
                           in the routing state calculation and
                           path selection.";
                      }
                      leaf process-id {
                        type uint16;
                        description



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                          "Process id of the IS-IS CE-PE
                           connection.";
                      }
                      leaf mode {
                        type enumeration {
                          enum active {
                            description
                              "Interface sends or receives IS-IS
                               protocol control packets.";
                          }
                          enum passive {
                            description
                              "Suppresses the sending of IS-IS
                               updates through the specified
                               interface.";
                          }
                        }
                        default "active";
                        description
                          "IS-IS interface mode type.";
                      }
                      uses vpn-common:service-status;
                      description
                        "IS-IS specific configuration.";
                    }
                    container static {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:static')" {
                        description
                          "Only applies when protocol is static.
                           BGP activation requires the SP to know
                           the address of the customer peer.  When
                           BGP is enabled, the 'static-address'
                           allocation type for the IP connection
                           must be used.";
                      }
                      container cascaded-lan-prefixes {
                        list ipv4-lan-prefixes {
                          if-feature "vpn-common:ipv4";
                          key "lan next-hop";
                          leaf lan {
                            type inet:ipv4-prefix;
                            description
                              "LAN prefixes.";
                          }
                          leaf lan-tag {
                            type string;
                            description



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                              "Internal tag to be used in VPN
                               policies.";
                          }
                          leaf next-hop {
                            type inet:ipv4-address;
                            description
                              "Next-hop address to use on the
                               customer side.";
                          }
                          description
                            "List of LAN prefixes for the site.";
                        }
                        list ipv6-lan-prefixes {
                          if-feature "vpn-common:ipv6";
                          key "lan next-hop";
                          leaf lan {
                            type inet:ipv6-prefix;
                            description
                              "LAN prefixes.";
                          }
                          leaf lan-tag {
                            type string;
                            description
                              "Internal tag to be used in VPN
                               policies.";
                          }
                          leaf next-hop {
                            type inet:ipv6-address;
                            description
                              "Next-hop address to use on the
                               customer side.";
                          }
                          description
                            "List of LAN prefixes for the site.";
                        }
                        description
                          "LAN prefixes from the customer.";
                      }
                      description
                        "Configuration specific to static routing.";
                    }
                    container rip {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:rip')" {
                        description
                          "Only applies when the protocol is RIP.
                           For IPv4, the model assumes that RIP
                           version 2 is used.";



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                      }
                      if-feature "vpn-common:rtg-rip";
                      leaf-list address-family {
                        type vpn-common:address-family;
                        min-elements 1;
                        description
                          "If RIP is used on this site, this node
                           contains a configured value.  This node
                           contains at least one address family
                           to be activated.";
                      }
                      description
                        "Configuration specific to RIP routing.";
                    }
                    container vrrp {
                      when "derived-from-or-self(../type, "
                         + "'vpn-common:vrrp')" {
                        description
                          "Only applies when protocol is VRRP.";
                      }
                      if-feature "vpn-common:rtg-vrrp";
                      leaf-list address-family {
                        type vpn-common:address-family;
                        min-elements 1;
                        description
                          "If VRRP is used on this site, this node
                           contains a configured value.  This node
                           contains at least one address family to
                           be activated.";
                      }
                      leaf vrrp-group {
                        type uint8 {
                          range "1..255";
                        }
                        description
                          "VRRP group number";
                      }
                      leaf backup-peer {
                        type inet:ip-address;
                        description
                          "IP address of the peer";
                      }
                      leaf priority {
                        type uint8;
                        description
                          "Local priority of the VRRP speaker";
                      }
                      leaf ping-reply {



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                        type boolean;
                        description
                          "Whether the VRRP speaker should answer
                           to ping requests";
                      }
                      description
                        "Configuration specific to VRRP.";
                    }
                    description
                      "List of routing protocols used on
                       the site.  This list can be augmented.";
                  }
                  description
                    "Defines routing protocols.";
                }
                container service {
                  leaf svc-input-bandwidth {
                    type uint64;
                    units "bps";
                    mandatory true;
                    description
                      "From the customer site's perspective, the
                       service input bandwidth of the connection
                       or download bandwidth from the SP to
                       the site.";
                  }
                  leaf svc-output-bandwidth {
                    type uint64;
                    units "bps";
                    mandatory true;
                    description
                      "From the customer site's perspective,
                       the service output bandwidth of the
                       connection or upload bandwidth from
                       the site to the SP.";
                  }
                  leaf svc-mtu {
                    type uint16;
                    units "bytes";
                    mandatory true;
                    description
                      "MTU at service level.  If the service is IP,
                       it refers to the IP MTU.  If CsC is enabled,
                       the requested 'svc-mtu' leaf will refer
                        to the MPLS MTU and not to the IP MTU.";
                  }
                  container qos {
                    if-feature "vpn-common:qos";



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                    container qos-classification-policy {
                      list rule {
                        key "id";
                        ordered-by user;
                        leaf id {
                          type string;
                          description
                            "A description identifying the
                             qos-classification-policy rule.";
                        }
                        choice match-type {
                          default "match-flow";
                          case match-flow {
                            choice l3 {
                              container ipv4 {
                                uses pf:acl-ip-header-fields;
                                uses pf:acl-ipv4-header-fields;
                                description
                                  "Rule set that matches IPv4 header.";
                              }
                              container ipv6 {
                                uses pf:acl-ip-header-fields;
                                uses pf:acl-ipv6-header-fields;
                                description
                                  "Rule set that matches IPv6 header.";
                              }
                              description
                                "Either IPv4 or IPv6.";
                            }
                            choice l4 {
                              container tcp {
                                uses pf:acl-tcp-header-fields;
                                uses ports;
                                description
                                  "Rule set that matches TCP header.";
                              }
                              container udp {
                                uses pf:acl-udp-header-fields;
                                uses ports;
                                description
                                  "Rule set that matches UDP header.";
                              }
                              description
                                "Can be TCP or UDP";
                            }
                          }
                          case match-application {
                            leaf match-application {



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                              type identityref {
                                base vpn-common:customer-application;
                              }
                              description
                                "Defines the application to match.";
                            }
                          }
                          description
                            "Choice for classification.";
                        }
                        leaf target-class-id {
                          type string;
                          description
                            "Identification of the class of service.
                             This identifier is internal to the
                             administration.";
                        }
                        description
                          "List of marking rules.";
                      }
                      description
                        "Configuration of the traffic classification
                         policy.";
                    }
                    container qos-profile {
                      list qos-profile {
                        key "profile";
                        description
                          "QoS profile.
                           Can be standard profile or customized
                           profile.";
                        leaf profile {
                          type leafref {
                            path "/l3vpn-ntw/vpn-profiles"
                               + "/valid-provider-identifiers"
                               + "/qos-profile-identifier/id";
                          }
                          description
                            "QoS profile to be used.";
                        }
                        leaf direction {
                          type identityref {
                            base vpn-common:qos-profile-direction;
                          }
                          default "vpn-common:both";
                          description
                            "The direction to which the QoS profile
                             is applied.";



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                        }
                      }
                      description
                        "QoS profile configuration.";
                    }
                    description
                      "QoS configuration.";
                  }
                  container carrierscarrier {
                    if-feature "vpn-common:carrierscarrier";
                    leaf signalling-type {
                      type enumeration {
                        enum ldp {
                          description
                            "Use LDP as the signalling protocol
                             between the PE and the CE.  In this
                             case, an IGP routing protocol must
                             also be activated.";
                        }
                        enum bgp {
                          description
                            "Use BGP as the signalling protocol
                             between the PE and the CE.
                             In this case, BGP must also be configured
                             as the routing protocol.";
                          reference
                            "RFC 8277: Using BGP to Bind MPLS Labels
                                       to Address Prefixes";
                        }
                      }
                      default "bgp";
                      description
                        "MPLS signalling type.";
                    }
                    description
                      "This container is used when the customer
                       provides MPLS-based services.  This is
                       only used in the  case of CsC (i.e., a
                       customer builds an MPLSservice using an
                       IP VPN to carry its traffic).";
                  }
                  container multicast {
                    if-feature "vpn-common:multicast";
                    leaf site-type {
                      type enumeration {
                        enum receiver-only {
                          description
                            "The site only has receivers.";



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                        }
                        enum source-only {
                          description
                            "The site only has sources.";
                        }
                        enum source-receiver {
                          description
                            "The site has both sources and
                             receivers.";
                        }
                      }
                      default "source-receiver";
                      description
                        "Type of multicast site.";
                    }
                    leaf address-family {
                      type vpn-common:address-family;
                      description
                        "Address family.";
                    }
                    leaf protocol-type {
                      type enumeration {
                        enum host {
                          description
                            "Hosts are directly connected to the
                             provider network.

                             Host protocols such as IGMP or MLD are
                             required.";
                        }
                        enum router {
                          description
                            "Hosts are behind a customer router.
                             PIM will be implemented.";
                        }
                        enum both {
                          description
                            "Some hosts are behind a customer router,
                             and some others are directly connected
                             to the provider network.  Both host and
                             routing protocols must be used.

                             Typically,  IGMP and PIM will be
                             implemented.";
                        }
                      }
                      default "both";
                      description



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                        "Multicast protocol type to be used with
                         the customer site.";
                    }
                    leaf remote-source {
                      type boolean;
                      default "false";
                      description
                        "When true, there is no PIM adjacency on
                         the interface.";
                    }
                    description
                      "Multicast parameters for the site.";
                  }
                  description
                    "Service parameters on the attachment.";
                }
                description
                  "List of accesses for a site.";
              }
              description
                "List of accesses for a site.";
            }
            container maximum-routes {
              list address-family {
                key "af";
                leaf af {
                  type vpn-common:address-family;
                  description
                    "Indicates the address family
                    (IPv4 or IPv6).";
                }
                leaf maximum-routes {
                  type uint32;
                  description
                    "Indicates the maximum prefixes the VRF
                     can accept for this address family.";
                }
                description
                  "List of address families.";
              }
              description
                "Defines 'maximum-routes' for the VRF.";
            }
            container multicast {
              if-feature "vpn-common:multicast";
              leaf enabled {
                type boolean;
                default "false";



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                description
                  "Enables multicast.";
              }
              leaf-list tree-flavor {
                type identityref {
                  base vpn-common:multicast-tree-type;
                }
                description
                  "Type of tree to be used.";
              }
              container rp {
                container rp-group-mappings {
                  list rp-group-mapping {
                    key "id";
                    leaf id {
                      type uint16;
                      description
                        "Unique identifier for the mapping.";
                    }
                    container provider-managed {
                      leaf enabled {
                        type boolean;
                        default "false";
                        description
                          "Set to true if the Rendezvous Point (RP)
                           must be a provider-managed node.  Set to
                           false if it is a customer-managed node.";
                      }
                      leaf rp-redundancy {
                        type boolean;
                        default "false";
                        description
                          "If true, a redundancy mechanism for the
                           RP is required.";
                      }
                      leaf optimal-traffic-delivery {
                        type boolean;
                        default "false";
                        description
                          "If true, the SP must ensure that
                           traffic uses an optimal path.  An SP may
                           use Anycast RP or RP-tree-to-SPT
                           switchover architectures.";
                      }
                      container anycast {
                        when "../rp-redundancy = 'true' and
                              ../optimal-traffic-delivery = 'true'" {
                          description



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                            "Only applicable if
                             RP redundancy is
                             enabled and delivery through
                             optimal path is activated.";
                        }
                        leaf local-address {
                          type inet:ip-address;
                          description
                            "IP local address for PIM RP.
                             Usually, it corresponds to router
                             ID or primary address";
                        }
                        leaf-list rp-set-address {
                          type inet:ip-address;
                          description
                            "Address other RP routers
                             that share the same RP IP address.";
                        }
                        description
                          "PIM Anycast-RP parameters.";
                      }
                      description
                        "Parameters for a provider-managed RP.";
                    }
                    leaf rp-address {
                      when "../provider-managed/enabled = 'false'" {
                        description
                          "Relevant when the RP is not
                           provider-managed.";
                      }
                      type inet:ip-address;
                      mandatory true;
                      description
                        "Defines the address of the RP.
                         Used if the RP is customer-managed.";
                    }
                    container groups {
                      list group {
                        key "id";
                        leaf id {
                          type uint16;
                          description
                            "Identifier for the group.";
                        }
                        choice group-format {
                          mandatory true;
                          case group-prefix {
                            leaf group-address {



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                              type inet:ip-prefix;
                              description
                                "A single multicast group prefix.";
                            }
                          }
                          case startend {
                            leaf group-start {
                              type inet:ip-address;
                              description
                                "The first multicast group address in
                                 the multicast group address range.";
                            }
                            leaf group-end {
                              type inet:ip-address;
                              description
                                "The last multicast group address in
                                 the multicast group address range.";
                            }
                          }
                          description
                            "Choice for multicast group format.";
                        }
                        description
                          "List of multicast groups.";
                      }
                      description
                        "Multicast groups associated with the RP.";
                    }
                    description
                      "List of RP-to-group mappings.";
                  }
                  description
                    "RP-to-group mappings parameters.";
                }
                container rp-discovery {
                  leaf rp-discovery-type {
                    type identityref {
                      base vpn-common:multicast-rp-discovery-type;
                    }
                    default "vpn-common:static-rp";
                    description
                      "Type of RP discovery used.";
                  }
                  container bsr-candidates {
                    when "derived-from-or-self(../rp-discovery-type, "
                       + "'vpn-common:bsr-rp')" {
                      description
                        "Only applicable if discovery type



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                         is BSR-RP.";
                    }
                    leaf-list bsr-candidate-address {
                      type inet:ip-address;
                      description
                        "Address of candidate Bootstrap Router
                        (BSR).";
                    }
                    description
                      "Container for List of Customer
                       BSR candidate's addresses.";
                  }
                  description
                    "RP discovery parameters.";
                }
                description
                  "RP parameters.";
              }
              container msdp {
                if-feature "msdp";
                leaf enabled {
                  type boolean;
                  default "false";
                  description
                    "If true, MSDP is activated.";
                }
                leaf peer {
                  type inet:ip-address;
                  description
                    "IP address of the MSDP peer.";
                }
                leaf local-address {
                  type inet:ip-address;
                  description
                    "IP address of the local end. This local
                     address must be configured on the
                     node.";
                }
                description
                  "MSDP parameters.";
              }
              description
                "Multicast global parameters for the VPN
                 service.";
            }
            description
              "List for VPN node.";
          }



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        }
        description
          "List of VPN services.";
      }
      description
        "Top-level container for the VPN services.";
    }
    description
      "Main container for L3VPN services management.";
  }
}
<CODE ENDS>

                                 Figure 25

9.  IANA Considerations

   This document requests IANA to register the following URI in the "ns"
   subregistry within the "IETF XML Registry" [RFC3688]:

         URI: urn:ietf:params:xml:ns:yang:ietf-l3vpn-ntw
         Registrant Contact: The IESG.
         XML: N/A; the requested URI is an XML namespace.

   This document requests IANA to register the following YANG module in
   the "YANG Module Names" subregistry [RFC6020] within the "YANG
   Parameters" registry.

         name: ietf-l3vpn-ntw
         namespace: urn:ietf:params:xml:ns:yang:ietf-l3vpn-ntw
         maintained by IANA: N
         prefix: l3nm
         reference: RFC XXXX

10.  Security Considerations

   The YANG module specified in this document defines 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
   [RFC8466].

   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.



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   The "ietf-l3vpn-ntw" module is used to manage Layer 3 VPNs in a
   service provider backbone network.  Hence, the module can be used to
   request, modify, or retrieve L3VPN services.  For example, the
   creation of a 'vpn-service' leaf instance triggers the creation of an
   L3VPN Service in a service provider network.

   Due to the foreseen use of the "ietf-l3vpn-ntw" module, there are a
   number of data nodes defined in the module that are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes MAY be considered sensitive or vulnerable
   in some network environments.  Write operations (e.g., edit-config)
   and delete operations to these data nodes without proper protection
   or authentication can have a negative effect on network operations.
   These are the subtrees and data nodes and their sensitivity/
   vulnerability in the "ietf-l3vpn-ntw" module:

   o  'vpn-service': An attacker who is able to access network nodes can
      undertake various attacks, such as deleting a running L3VPN
      Service, interrupting all the traffic of a client.  In addition,
      an attacker may modify the attributes of a running service (e.g.,
      QoS, bandwidth, routing protocols), leading to malfunctioning of
      the service and therefore to SLA violations.  In addition, an
      attacker could attempt to create a L3VPN Service or adding a new
      network access.  Such activity can be detected by adequately
      monitoring and tracking network configuration changes.

   Some of the readable data nodes in the "ietf-l3vpn-ntw" 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:

   o  'customer-name' and 'ip-connection': An attacker can retrieve
      privacy-related information which can be used to track a customer.
      Disclosing such information may be considered as a violation of
      the customer-provider trust relationship.

   The following summarizes the foreseen risks of using the "ietf-l3vpn-
   ntw" module can be classified into:

   o  Malicious clients attempting to delete or modify VPN services.

   o  Unauthorized clients attempting to create/modify/delete a VPN
      service.

   o  Unauthorized clients attempting to read VPN service related
      information.




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11.  Acknowledgements

   Thanks to Adrian Farrel and Miguel Cros for the suggestions on the
   document.  Thanks to Philip Eardlay for the review.  Lots of thanks
   for the discussions on opsawg mailing list and at IETF meeting.

   This work was supported in part by the European Commission funded
   H2020-ICT-2016-2 METRO-HAUL project (G.A. 761727).

12.  Contributors

   Victor Lopez
   Telefonica
   Email: victor.lopezalvarez@telefonica.com

   Daniel King
   Old Dog Consulting
   Email: daniel@olddog.co.uk

   Daniel Voyer
   Bell Canada
   Email: daniel.voyer@bell.ca

   Luay Jalil
   Verizon
   Email: luay.jalil@verizon.com

   Qin Wu
   Huawei
   Email: bill.wu@huawei.com>

   Stephane Litkowski
   Cisco
   Email: slitkows@cisco.com>

   Manuel Julian
   Vodafone
   Email: manuel-julian.lopez@vodafone.com>

   Lucia Oliva Ballega
   Telefonica
   Email: lucia.olivaballega.ext@telefonica.com>

   Erez Segev
   ECI Telecom
   Email: erez.segev@ecitele.com>





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13.  References

13.1.  Normative References

   [I-D.ietf-opsawg-vpn-common]
              barguil, s., Dios, O., Boucadair, M., and Q. WU, "A Layer
              2/3 VPN Common YANG Model", draft-ietf-opsawg-vpn-
              common-01 (work in progress), September 2020.

   [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>.

   [RFC4110]  Callon, R. and M. Suzuki, "A Framework for Layer 3
              Provider-Provisioned Virtual Private Networks (PPVPNs)",
              RFC 4110, DOI 10.17487/RFC4110, July 2005,
              <https://www.rfc-editor.org/info/rfc4110>.

   [RFC4364]  Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private
              Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February
              2006, <https://www.rfc-editor.org/info/rfc4364>.

   [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>.

   [RFC6513]  Rosen, E., Ed. and R. Aggarwal, Ed., "Multicast in MPLS/
              BGP IP VPNs", RFC 6513, DOI 10.17487/RFC6513, February
              2012, <https://www.rfc-editor.org/info/rfc6513>.







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   [RFC6514]  Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP
              Encodings and Procedures for Multicast in MPLS/BGP IP
              VPNs", RFC 6514, DOI 10.17487/RFC6514, February 2012,
              <https://www.rfc-editor.org/info/rfc6514>.

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [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>.

   [RFC7988]  Rosen, E., Ed., Subramanian, K., and Z. Zhang, "Ingress
              Replication Tunnels in Multicast VPN", RFC 7988,
              DOI 10.17487/RFC7988, October 2016,
              <https://www.rfc-editor.org/info/rfc7988>.

   [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>.

   [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>.

   [RFC8466]  Wen, B., Fioccola, G., Ed., Xie, C., and L. Jalil, "A YANG
              Data Model for Layer 2 Virtual Private Network (L2VPN)
              Service Delivery", RFC 8466, DOI 10.17487/RFC8466, October
              2018, <https://www.rfc-editor.org/info/rfc8466>.

   [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, March 2019,
              <https://www.rfc-editor.org/info/rfc8519>.

13.2.  Informative References

   [I-D.evenwu-opsawg-yang-composed-vpn]
              Even, R., Bo, W., Wu, Q., and Y. Cheng, "YANG Data Model
              for Composed VPN Service Delivery", draft-evenwu-opsawg-
              yang-composed-vpn-03 (work in progress), March 2019.




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   [I-D.ietf-idr-bgp-model]
              Jethanandani, M., Patel, K., Hares, S., and J. Haas, "BGP
              YANG Model for Service Provider Networks", draft-ietf-idr-
              bgp-model-09 (work in progress), June 2020.

   [I-D.ietf-pim-yang]
              Liu, X., McAllister, P., Peter, A., Sivakumar, M., Liu,
              Y., and f. hu, "A YANG Data Model for Protocol Independent
              Multicast (PIM)", draft-ietf-pim-yang-17 (work in
              progress), May 2018.

   [I-D.ietf-rtgwg-qos-model]
              Choudhary, A., Jethanandani, M., Strahle, N., Aries, E.,
              and I. Chen, "YANG Model for QoS", draft-ietf-rtgwg-qos-
              model-02 (work in progress), July 2020.

   [RFC3618]  Fenner, B., Ed. and D. Meyer, Ed., "Multicast Source
              Discovery Protocol (MSDP)", RFC 3618,
              DOI 10.17487/RFC3618, October 2003,
              <https://www.rfc-editor.org/info/rfc3618>.

   [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, November 2003,
              <https://www.rfc-editor.org/info/rfc3644>.

   [RFC4026]  Andersson, L. and T. Madsen, "Provider Provisioned Virtual
              Private Network (VPN) Terminology", RFC 4026,
              DOI 10.17487/RFC4026, March 2005,
              <https://www.rfc-editor.org/info/rfc4026>.

   [RFC4176]  El Mghazli, Y., Ed., Nadeau, T., Boucadair, M., Chan, K.,
              and A. Gonguet, "Framework for Layer 3 Virtual Private
              Networks (L3VPN) Operations and Management", RFC 4176,
              DOI 10.17487/RFC4176, October 2005,
              <https://www.rfc-editor.org/info/rfc4176>.

   [RFC4271]  Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A
              Border Gateway Protocol 4 (BGP-4)", RFC 4271,
              DOI 10.17487/RFC4271, January 2006,
              <https://www.rfc-editor.org/info/rfc4271>.

   [RFC5880]  Katz, D. and D. Ward, "Bidirectional Forwarding Detection
              (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010,
              <https://www.rfc-editor.org/info/rfc5880>.






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   [RFC6037]  Rosen, E., Ed., Cai, Y., Ed., and IJ. Wijnands, "Cisco
              Systems' Solution for Multicast in BGP/MPLS IP VPNs",
              RFC 6037, DOI 10.17487/RFC6037, October 2010,
              <https://www.rfc-editor.org/info/rfc6037>.

   [RFC6982]  Sheffer, Y. and A. Farrel, "Improving Awareness of Running
              Code: The Implementation Status Section", RFC 6982,
              DOI 10.17487/RFC6982, July 2013,
              <https://www.rfc-editor.org/info/rfc6982>.

   [RFC7527]  Asati, R., Singh, H., Beebee, W., Pignataro, C., Dart, E.,
              and W. George, "Enhanced Duplicate Address Detection",
              RFC 7527, DOI 10.17487/RFC7527, April 2015,
              <https://www.rfc-editor.org/info/rfc7527>.

   [RFC8277]  Rosen, E., "Using BGP to Bind MPLS Labels to Address
              Prefixes", RFC 8277, DOI 10.17487/RFC8277, October 2017,
              <https://www.rfc-editor.org/info/rfc8277>.

   [RFC8299]  Wu, Q., Ed., Litkowski, S., Tomotaki, L., and K. Ogaki,
              "YANG Data Model for L3VPN Service Delivery", RFC 8299,
              DOI 10.17487/RFC8299, January 2018,
              <https://www.rfc-editor.org/info/rfc8299>.

   [RFC8309]  Wu, Q., Liu, W., and A. Farrel, "Service Models
              Explained", RFC 8309, DOI 10.17487/RFC8309, January 2018,
              <https://www.rfc-editor.org/info/rfc8309>.

   [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>.

   [RFC8342]  Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore Architecture
              (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
              <https://www.rfc-editor.org/info/rfc8342>.

   [RFC8345]  Clemm, A., Medved, J., Varga, R., Bahadur, N.,
              Ananthakrishnan, H., and X. Liu, "A YANG Data Model for
              Network Topologies", RFC 8345, DOI 10.17487/RFC8345, March
              2018, <https://www.rfc-editor.org/info/rfc8345>.

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





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   [RFC8453]  Ceccarelli, D., Ed. and Y. Lee, Ed., "Framework for
              Abstraction and Control of TE Networks (ACTN)", RFC 8453,
              DOI 10.17487/RFC8453, August 2018,
              <https://www.rfc-editor.org/info/rfc8453>.

   [RFC8512]  Boucadair, M., Ed., Sivakumar, S., Jacquenet, C.,
              Vinapamula, S., and Q. Wu, "A YANG Module for Network
              Address Translation (NAT) and Network Prefix Translation
              (NPT)", RFC 8512, DOI 10.17487/RFC8512, January 2019,
              <https://www.rfc-editor.org/info/rfc8512>.

Appendix A.  L3VPN Examples

A.1.  4G VPN Provisioning Example

   L3VPNs are widely used to deploy 3G/4G, fixed, and enterprise
   services mainly because several traffic discrimination policies can
   be applied within the network to deliver to the mobile customers a
   service that meets the SLA requirements.

   As it is shown in the Figure 26, typically, an eNodeB (CE) is
   directly connected to the access routers of the mobile backhaul and
   their logical interfaces (one or many according to the Service type)
   are configured in a VPN that transports the packets to the mobile
   core platforms.  In this example, a 'vpn-node' is created with two
   'vpn-network-accesses'.

         +-------------+                  +------------------+
         |             |                  | PE               |
         |             | 192.0.2.2        |  10.0.0.1        |
         |   eNodeB    |>--------/------->|...........       |
         |             |          Vlan 1  |          |       |
         |             |>--------/------->|......    |       |
         |             |          Vlan 2  |     |    |       |
         |             | Direct           |  +-------------+ |
         +-------------+ Routing          |  | vpn-node-id | |
                                          |  | 44          | |
                                          |  +-------------+ |
                                          |                  |
                                          +------------------+

                    Figure 26: Mobile Backhaul Example

   To create a L3VPN service using the L3NM model, the following sample
   steps can be followed:

   First: Create the 4G VPN Service (Figure 27).




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   POST: /restconf/data/ietf-l3vpn-ntw:l3vpn-ntw/vpn-services
   Host: example.com
   Content-Type: application/yang-data+json

   {
     "ietf-l3vpn-ntw:vpn-services": {
       "vpn-service": [
         {
           "vpn-id": "4G",
           "customer-name": "mycustomer",
           "vpn-service-topology": "custom",
           "description": "VPN to deploy 4G services"
         }
       ]
     }
   }

                       Figure 27: Create VPN Service

   Second: Create a VPN Node as depicted in Figure 28.  In this type of
   service, the VPN Node is equivalent to the VRF configured in the
   physical device ('ne-id'=10.0.0.1).





























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   POST: /restconf/data/ietf-l3vpn-ntw:l3vpn-ntw/\
         vpn-services/vpn-service=4G
   Host: example.com
   Content-Type: application/yang-data+json

   {
     "ietf-l3vpn-ntw:vpn-nodes": {
       "vpn-node": [
         {
           "vpn-node-id": "44",
           "ne-id": "10.0.0.1",
           "local-autonomous-system": "65550",
           "rd": "0:65550:1",
           "vpn-targets": {
             "vpn-target": [
               {
                 "id": "1",
                 "route-targets": [
                   "0:65550:1"
                 ],
                 "route-target-type": "both"
               }
             ]
           }
         }
       ]
     }
   }

                        Figure 28: Create VPN Node

   Finally, two VPN Network Accesses are created using the same physical
   port ('port-id'=1/1/1).  Each 'vpn-network-access' has a particular
   VLAN (1,2) to differentiate the traffic between: Sync and data
   (Figure 29).

   POST: /restconf/data/ietf-l3vpn-ntw:l3vpn-ntw/\
         vpn-services/vpn-service=4G/vpn-nodes/vpn-node=44
   content-type: application/yang-data+json

   {
     "ietf-l3vpn-ntw:vpn-network-accesses": {
       "vpn-network-access": [
         {
           "vpn-network-access-id": "1/1/1.1",
           "port-id": "1/1/1",
           "description": "Interface SYNC to eNODE-B",
           "status": {



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             "admin-enabled": "true"
           },
           "vpn-network-access-type": "vpn-common:point-to-point",
           "ip-connection": {
             "ipv4": {
               "address-allocation-type": "static-address",
               "static-addresses": {
                 "primary-address": "1",
                 "address": [
                   {
                     "address-id": "1",
                     "s-provider-address": "192.0.2.1",
                     "s-customer-address": "192.0.2.1",
                     "s-prefix-length": 32
                   }
                 ]
               }
             }
           },
           "routing-protocols": {
             "routing-protocol": [
               {
                 "id": "1",
                 "type": "vpn-common:direct"
               }
             ]
           }
         },
         {
           "vpn-network-access-id": "1/1/1.2",
           "port-id": "1/1/1",
           "description": "Interface DATA to eNODE-B",
           "status": {
             "admin-enabled": "true"
           },
           "ip-connection": {
             "ipv4": {
               "address-allocation-type": "static-address",
               "static-addresses": {
                 "primary-address": "1",
                 "address": [
                   {
                     "address-id": "1",
                     "s-provider-address": "192.0.2.1",
                     "s-customer-address": "192.0.2.2",
                     "s-prefix-length": 32
                   }
                 ]



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               }
             }
           },
           "routing-protocols": {
             "routing-protocol": [
               {
                 "id": "1",
                 "type": "vpn-common:direct"
               }
             ]
           }
         }
       ]
     }
   }

                   Figure 29: Create VPN Network Access

A.2.  Multicast VPN Provisioning Example

   IPTV is mainly distributed through multicast over the LANs.  In the
   following example, PIM-SM is enabled and functional between the PE
   and the CE.  The PE receives multicast traffic from a CE that is
   directly connected to the multicast source.  The signaling between PE
   and CE is achieved using BGP.  Also, RP is statically configured for
   a multicast group.

                 +-----------+   +------+     +------+    +-----------+
                 | Multicast |---|  CE  |--/--|  PE  |----|  Backbone |
                 |  source   |   +------+     +------+    |   IP/MPLS |
                 +-----------+                            +-----------+


                Figure 30: Multicast L3VPN Service Example

   To configure a Multicast L3VPN service using the L3NM model the
   procedure and the JSON with the data structure is the following:

   First, the multicast service is created (see the excerpt of the
   request message body shown in Figure 31)











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   {
     "ietf-l3vpn-ntw:vpn-services": {
       "vpn-service": [
         {
           "vpn-id": "Multicast-IPTV",
           "customer-name": "310",
           "vpn-service-topology": "vpn-common:hub-spoke",
           "description": "Multicast IPTV VPN service"
         }
       ]
     }
   }

      Figure 31: Create Multicast VPN Service (Excerpt of the Message
                               Request Body)

   Then, the VPN nodes are created (see the excerpt of the request
   message body shown in Figure 32).  In this example, the VPN Node will
   represent VRF configured in the physical device.
































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   {
     "ietf-l3vpn-ntw:vpn-node": [
       {
         "vpn-node-id": "500003105",
         "ne-id": "10.250.2.202",
         "autonomous-system": "3816",
         "description": "VRF_IPTV_MULTICAST",
         "router-id": "10.250.2.202",
         "address-family": "ipv4",
         "node-role": "vpn-common:hub-role",
         "rd": "3816:31050202",
         "multicast": {
           "enabled": "true",
           "rp": {
             "rp-group-mappings": {
               "rp-group-mapping": [
                 {
                   "id": "1",
                   "rp-address": "172.19.48.17",
                   "groups": {
                     "group": [
                       {
                         "id": "1",
                         "group-address": "239.130.0.0/15"
                       }
                     ]
                   }
                 }
               ]
             },
             "rp-discovery": {
               "rp-discovery-type": "vpn-common:static-rp"
             }
           }
         }
       }
     ]
   }

   Figure 32: Create Multicast VPN Node (Excerpt of the Message Request
                                   Body)

   Finally, create the VPN Network Access with multicast enabled (see
   the excerpt of the request message body shown in Figure 33).

    {
     "ietf-l3vpn-ntw:vpn-network-access": {
       "vpn-network-access-id": "1/1/1",



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       "description": "Connected_to_source",
       "status": {
         "admin-enabled": "true"
       },
       "vpn-network-access-type": "vpn-common:point-to-point",
       "ip-connection": {
         "ipv4": {
           "address-allocation-type": "static-address",
           "static-addresses": {
             "primary-address": "1",
             "address": [
               {
                 "address-id": "1",
                 "s-provider-address": "172.19.48.1",
                 "s-prefix-length": 30
               }
             ]
           }
         }
       },
       "routing-protocols": {
         "routing-protocol": [
           {
             "id": "1",
             "type": "vpn-common:bgp",
             "bgp": {
               "peer-autonomous-system": "6500",
               "local-autonomous-system": "3816",
               "address-family": "ipv4",
               "neighbor": "172.19.48.2",
               "description": "Connected to CE"
             }
           }
         ]
       },
       "service": {
         "multicast": {
           "multicast-site-type": "source-only",
           "multicast-address-family": {
             "ipv4": "true"
           },
           "protocol-type": "router"
         }
       }
     }
   }





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   Figure 33: Create VPN Network Access (Excerpt of the Message Request
                                   Body)

Appendix B.  Implementation Status

   This section records the status of known implementations of the Yang
   module defined by this specification at the time of posting of this
   Internet-Draft, and is based on a proposal described in [RFC6982].
   The description of implementations in this section is intended to
   assist the IETF in its decision processes in progressing drafts to
   RFCs.  Please note that the listing of any individual implementation
   here does not imply endorsement by the IETF.  Furthermore, no effort
   has been spent to verify the information presented here that was
   supplied by IETF contributors.  This is not intended as, and must not
   be construed to be, a catalog of available implementations or their
   features.  Readers are advised to note that other implementations may
   exist.

   According to [RFC6982], "this will allow reviewers and working groups
   to assign due consideration to documents that have the benefit of
   running code, which may serve as evidence of valuable experimentation
   and feedback that have made the implemented protocols more mature.
   It is up to the individual working groups to use this information as
   they see fit".

   Note the RFC Editor: As per [RFC6982] guidelines, please remove this
   Implementation Status apendix prior publication.

B.1.  Nokia Implementation

   Details can be found at: https://github.com/IETF-OPSAWG-
   WG/l3nm/blob/master/Implementattion/Nokia.txt

B.2.  Huawei Implementation

   Details can be found at: https://github.com/IETF-OPSAWG-
   WG/l3nm/blob/master/Implementattion/Huawei.txt

B.3.  Infinera Implementation

   Details can be found at: https://github.com/IETF-OPSAWG-
   WG/l3nm/blob/master/Implementattion/Infinera.txt

B.4.  Ribbon-ECI Implementation

   Details can be found at: https://github.com/IETF-OPSAWG-
   WG/l3nm/blob/master/Implementattion/Ribbon-ECI.txt




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Authors' Addresses

   Samier Barguil
   Telefonica
   Madrid
   ES

   Email: samier.barguilgiraldo.ext@telefonica.com


   Oscar Gonzalez de Dios (editor)
   Telefonica
   Madrid
   ES

   Email: oscar.gonzalezdedios@telefonica.com


   Mohamed Boucadair (editor)
   Orange
   Rennes 35000
   France

   Email: mohamed.boucadair@orange.com


   Luis Angel Munoz
   Vodafone
   ES

   Email: luis-angel.munoz@vodafone.com


   Alejandro Aguado
   Nokia
   Madrid
   ES

   Email: alejandro.aguado_martin@nokia.com












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