[Docs] [txt|pdf|xml|html] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-zhuang-i2rs-yang-dc-fabric-network-topology) 00 01 02 03 04 05 06 07 08 09 10 11 12 RFC 8542

I2RS Working Group                                             Y. Zhuang
Internet-Draft                                                    D. Shi
Intended status: Standards Track                                  Huawei
Expires: June 25, 2018                                             R. Gu
                                                            China Mobile
                                                      H. Ananthakrishnan
                                                           Packet Design
                                                       December 22, 2017


      A YANG Data Model for Fabric Topology in Data Center Network
           draft-ietf-i2rs-yang-dc-fabric-network-topology-03

Abstract

   This document defines a YANG data model for fabric topology in Data
   Center Network.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on June 25, 2018.

Copyright Notice

   Copyright (c) 2017 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of




Zhuang, et al.            Expires June 25, 2018                 [Page 1]


Internet-Draft      Data model for DC fabric topology      December 2017


   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Definitions an Acronyms . . . . . . . . . . . . . . . . . . .   3
     2.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   3
     2.2.  Tree diagram  . . . . . . . . . . . . . . . . . . . . . .   4
   3.  Model Overview  . . . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  Topology Model structure  . . . . . . . . . . . . . . . .   4
     3.2.  Fabric Topology Model . . . . . . . . . . . . . . . . . .   5
       3.2.1.  Fabric Topology . . . . . . . . . . . . . . . . . . .   5
       3.2.2.  Fabric node extension . . . . . . . . . . . . . . . .   6
       3.2.3.  Fabric termination-point extension  . . . . . . . . .   7
   4.  Fabric YANG Module  . . . . . . . . . . . . . . . . . . . . .   8
   5.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  20
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  21
   7.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  22
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  22
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  22
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  23
   Appendix A.  Non NMDA -state modules  . . . . . . . . . . . . . .  23
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  29

1.  Introduction

   Normally, a data center network is composed of single or multiple
   fabrics which are also known as PODs (a Point Of Delivery).  These
   fabrics may be heterogeneous due to implementation of different
   technologies while DC network upgrading or enrolling new techniques
   and features.  For example, Fabric A may use VXLAN while Fabric B may
   use VLAN within a DC network.  Likewise, a legacy Fabric may use
   VXLAN while a new Fabric B implemented technique discussed in NVO3 WG
   such as GPE[I-D. draft-ietf-nvo3-vxlan-gpe] may be built due to DC
   expansion and upgrading.  The configuration and management of such DC
   networks with heterogeneous fabrics will be sophisticated and
   complex.

   Luckily, for a DC network, a fabric can be considered as an atomic
   structure to provide network services and management, as well as
   expand network capacity.  From this point of view, the miscellaneous
   DC network management can be decomposed to task of managing each
   fabric respectively along with their connections, which can make the
   entire management much concentrated and flexible, also easy to
   expand.





Zhuang, et al.            Expires June 25, 2018                 [Page 2]


Internet-Draft      Data model for DC fabric topology      December 2017


   With this purpose, this document defines a YANG data model for the
   Fabric-based Data center topology by using YANG [6020][7950].  To do
   so, it augments the generic network and network topology data models
   defined in [I-D.ietf-i2rs-yang-network-topo] with information
   specific to Data Center fabric network.

   This model defines the generic configuration and operational state
   for a fabric-based network topology, which can be extended by vendors
   with specific information.  This model can then be used by a network
   controller to represent its view of the fabric topology that it
   controls and expose it to network administrators or applications for
   DC network management.

   With the context of topology architecture defined in [I-D.ietf-i2rs-
   yang-network-topo] and [I.D. draft-ietf-i2rs-usecase-reqs-summary],
   this model can also be treated as an application of I2RS network
   topology model [I-D.ietf-i2rs-yang-network-topo] in the scenario of
   Data center network management.  It can also act as a service
   topology when mapping network elements at fabric layer to elements to
   other topologies, such as L3 topology defined in [I.D. draft-ietf-
   i2rs-yang-l3-topology-01.

   By using this fabric topology model, people can treat a fabric as an
   entity and focus on characteristics of fabrics (such as encapsulation
   type, gateway type, etc.) as well as their interconnections while
   putting the underlay topology aside.  As such, clients can consume
   the topology information at fabric level, while no need to be aware
   of entire set of links and nodes in underlay networks.  The
   configuration of a fabric topology can be made by a network
   administractor to the controller by adding physical devices and links
   of a fabric into a fabric network.  Alternatively, the fabric
   topology can also learnt from the underlay network infrastructure.

2.  Definitions an Acronyms

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

2.1.  Terminology

   DC Fabric: also known as POD, is a module of network, compute,
   storage, and application components that work together to deliver
   networking services.  It is a repeatable design pattern, and its
   components maximize the modularity, scalability, and manageability of
   data centers.





Zhuang, et al.            Expires June 25, 2018                 [Page 3]


Internet-Draft      Data model for DC fabric topology      December 2017


2.2.  Tree diagram

   The following notations are used within the data tree and carry the
   meaning as below.

  Each node is printed as:
    <status> <flags> <name> <opts> <type>

    <status> is one of:
         +  for current
         x  for deprecated
         o  for obsolete
    <flags> is one of:
        rw for configuration data
        ro for non-configuration data
        -x for rpcs
        -n for notifications
    <name> is the name of the node

    If the node is augmented into the tree from another module, its name
    is printed as <prefix>:<name>.
    <opts> is one of:
         ?  for an optional leaf or choice
         !  for a presence container
         *  for a leaf-list or list
         [<keys>] for a list's keys
    <type> is the name of the type for leafs and leaf-lists

   In this document, these words will appear with that interpretation
   only when in ALL CAPS.  Lower case uses of these words are not to be
   interpreted as carrying RFC-2119 significance.

3.  Model Overview

   This section provides an overview of the DC Fabric topology model and
   its relationship with other topology models.

3.1.  Topology Model structure

   The relationship of the DC fabric topology model and other topology
   models is shown in the following figure (dotted lines in the figure
   denote augmentations).









Zhuang, et al.            Expires June 25, 2018                 [Page 4]


Internet-Draft      Data model for DC fabric topology      December 2017


             +------------------------+
             |      network model     |
             +------------------------+
                          |
                          |
             +------------V-----------+
             | network topology model |
             +------------------------+
                          |
        +-----------+-----+------+-------------+
        |           |            |             |
    +---V----+  +---V----+   +---V----+   +----V---+
    |   L1   |  |   L2   |   |   L3   |   | Fabric |
    |topology|  |topology|   |topology|   |topology|
    |  model |  |  model |   |  model |   |  model |
    +--------+  +--------+   +--------+   +--------+


   From the perspective of resource management and service provisioning
   for a Data Center network, the fabric topology model augments the
   basic network topology model with definitions and features specific
   to a DC fabric, to provide common configuration and operations for
   heterogeneous fabrics.

3.2.  Fabric Topology Model

   The fabric topology model module is designed to be generic and can be
   applied to data center fabrics built with different technologies,
   such as VLAN, VXLAN etc.  The main purpose of this module is to
   configure and manage fabrics and their connections. provide a fabric-
   based topology view for data center network applications.

3.2.1.  Fabric Topology

   In the fabric topology module, a fabric is modeled as a node in the
   network, while the fabric-based Data center network consists of a set
   of fabric nodes and their connections known as "fabric port".  The
   following is the snip of the definition to show the main structure of
   the model:












Zhuang, et al.            Expires June 25, 2018                 [Page 5]


Internet-Draft      Data model for DC fabric topology      December 2017


        module: ietf-fabric-topology
        augment /nw:networks/nw:network/nw:network-types:
           +--rw fabric-network!
        augment /nw:networks/nw:network/nw:node:
           +--rw fabric-attributes
                  +--rw fabric-id?              fabric-id
                  +--rw name?           string
                  +--rw type?           fabrictype:underlay-network-type
                  +--rw description?    string
                  +--rw options
                  +--...
        augment /nw:networks/nw:network/nw:node/nt:termination-point:
           +--ro fport-attributes
                  +--ro name?          string
                  +--ro role?          fabric-port-role
                  +--ro type?          fabric-port-type


   The fabric topology module augments the generic ietf-network and
   ietf-network-topology modules as follows:

   o  A new topology type "ietf-fabric-topology" is introduced and added
      under the "network-types" container of the ietf-network module.

   o  Fabric is defined as a node under the network/node container.  A
      new container of "fabric-attributes" is defined to carry
      attributes for a fabric network such as gateway mode, fabric
      types, involved device nodes and links etc.

   o  Termination points (in network topology module) are augmented with
      fabric port attributes defined in a container.  The "termination-
      point" here can represent the "port" of a fabric that provides
      connections to other nodes, such as device internally, another
      fabric externally and also end hosts.

   Details of fabric node and fabric termination point extension will be
   explained in the following sections.

3.2.2.  Fabric node extension

   As a network, a fabric itself is composed of set of network elements
   i.e. devices, and related links.  As stated previously, the
   configuration of a fabric is contained under the "fabric-attributes"
   container depicted as follows:







Zhuang, et al.            Expires June 25, 2018                 [Page 6]


Internet-Draft      Data model for DC fabric topology      December 2017


                +--rw fabric-attributes
                   +--rw fabric-id?      fabric-id
                   +--rw name?           string
                   +--rw type?           fabrictype:underlay-network-type
                   +--rw vni-capacity
                   |  +--rw min?   int32
                   |  +--rw max?   int32
                   +--rw description?    string
                   +--rw options
                   |  +--rw gateway-mode?           enumeration
                   |  +--rw traffic-behavior?       enumeration
                   |  +--rw capability-supported*   fabrictype:service-capabilities
                   +--rw device-nodes* [device-ref]
                   |  +--rw device-ref    fabrictype:node-ref
                   |  +--rw role?         fabrictype:device-role
                   +--rw device-links* [link-ref]
                   |  +--rw link-ref    fabrictype:link-ref
                   +--rw device-ports* [port-ref]
                          +--rw port-ref     fabrictype:tp-ref
                          +--rw port-type?   fabrictypes:port-type
                          +--rw bandwidth?   fabrictypes:bandwidth


   As in the module, additional data objects for nodes are introduced by
   augmenting the "node" list of the network module.  New objects
   include fabric name, type of the fabric, descriptions of the fabric
   as well as a set of options defined in an "options" container.  The
   options container includes type of the gateway-mode (centralized or
   distributed) and traffic-behavior (whether acl needed for the
   traffic).

   Also, it defines a list of device-nodes and related links as
   supporting-nodes to form a fabric network.  These device nodes and
   links are leaf-ref of existing nodes and links in the underlay
   topology.  For the device-node, the "role" object is defined to
   represents the role of the device within the fabric, such as "SPINE"
   or "LEAF", which should work together with gateway-mode.

3.2.3.  Fabric termination-point extension

   Since the fabric can be considered as a node, in this concept,
   "termination-points" can represent "ports" of a fabric that connects
   to other fabrics or end hosts, besides representing ports that
   connect devices inside the fabric itself.

   As such, the "termination-point" in the fabric topology has three
   roles, that are internal TP that connects to devices within a fabric,




Zhuang, et al.            Expires June 25, 2018                 [Page 7]


Internet-Draft      Data model for DC fabric topology      December 2017


   external TP that connects to outside network, and access TP to end
   hosts.

   The set of "termination-point" of a fabric indicates all connections
   of the fabric, including its internal connections, interconnections
   with other fabrics and also connections to end hosts for a DC
   network.

   The structure of fabric ports is as follows:

           augment /nw:networks/nw:network/nw:node/nt:termination-point:
                 +--ro fport-attributes
                    +--ro name?          string
                    +--ro role?          fabric-port-role
                    +--ro type?          fabric-port-type
                    +--ro device-port?   tp-ref
                    +--ro (tunnel-option)?


   It augments the termination points (in network topology module) with
   fabric port attributes defined in a container.

   New nodes are defined for fabric ports which include name, role of
   the port within the fabric (internal port, external port to outside
   network, access port to end hosts), port type (l2 interface, l3
   interface etc).  By defining the device-port as a tp-ref, a fabric
   port can be mapped to a device node in the underlay network.

   Also, a new container for tunnel-options is introduced to present the
   tunnel configuration on the port.

   The termination points information are all learnt from the underlay
   networks but not configured by the fabric topology layer.

4.  Fabric YANG Module


<CODE BEGINS> file "ietf-dc-fabric-types@2017-12-21.yang"
    module ietf-dc-fabric-types {

    yang-version 1.1;
    namespace "urn:ietf:params:xml:ns:yang:ietf-dc-fabric-types";
    prefix fabrictypes;

        organization
    "IETF I2RS (Interface to the Routing System) Working Group";

        contact



Zhuang, et al.            Expires June 25, 2018                 [Page 8]


Internet-Draft      Data model for DC fabric topology      December 2017


    "WG Web:    <http://tools.ietf.org/wg/i2rs/ >
     WG List:   <mailto:i2rs@ietf.org>

     Editor:    Yan Zhuang
                <mailto:zhuangyan.zhuang@huawei.com>

     Editor:    Danian Shi
                <mailto:shidanian@huawei.com>";

     description
        "This module contains a collection of YANG definitions for Fabric.
        Copyright (c) 2016 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
        (http://trustee.ietf.org/license-info).

        This version of this YANG module is part of
        draft-ietf-i2rs-yang-dc-fabric-network-topology;
        see the RFC itself for full legal notices.

        NOTE TO RFC EDITOR: Please replace above reference to
        draft-ietf-i2rs-yang-dc-fabric-network-topology-03 with RFC
        number when published (i.e. RFC xxxx).";

    revision "2017-12-21"{
        description
            "Initial revision.
             NOTE TO RFC EDITOR: Please replace the following reference to
             draft-ietf-i2rs-yang-dc-fabric-network-topology-03 with RFC
             number when published (i.e. RFC xxxx).";
        reference
            "draft-ietf-i2rs-yang-dc-fabric-network-topology-03";
        }

    identity fabric-type {
        description
           "Base type for fabric networks";
    }

    identity vxlan-fabric {
        base fabric-type;
        description "Vxlan fabric";
    }



Zhuang, et al.            Expires June 25, 2018                 [Page 9]


Internet-Draft      Data model for DC fabric topology      December 2017


    identity vlan-fabric {
        base fabric-type;
        description
           "Vlan fabric";
    }

    identity trill-fabric {
        base fabric-type;
        description "Trill fabric";
    }
    identity port-type {
        description
           "Base type for fabric port";
        }
    identity eth {
        base port-type;
        description "ETH";
    }
    identity serial {
        base port-type;
        description "Serial";
    }

    identity bandwidth {
        description "Base for bandwidth";
    }
    identity bw-1M {
        base bandwidth;
        description "1M";
    }
    identity bw-10M {
        base bandwidth;
        description "10M";
    }
    identity bw-100M {
        base bandwidth;
        description "100M";
    }
    identity bw-1G {
        base bandwidth;
        description "1G";
    }
    identity bw-10G {
        base bandwidth;
        description "10G";
    }
    identity bw-40G {
        base bandwidth;



Zhuang, et al.            Expires June 25, 2018                [Page 10]


Internet-Draft      Data model for DC fabric topology      December 2017


        description "40G";
    }
    identity bw-100G{
        base bandwidth;
        description "100G";
    }

    identity device-role {
        description "Base for the device role in a fabric.";
    }
    identity spine {
        base device-role;
        description "This is a spine node in a fabric.";
    }
    identity leaf {
        base device-role;
        description "This is a leaf node in a fabric. ";
    }
    identity border {
        base device-role;
        description "This is a border node to connect to
        other fabric/network.";
    }
    identity fabric-port-role {
        description "Base for the port's role in a fabric.";
    }
    identity internal {
        base fabric-port-role;
        description "The port is used for devices to access
        each other within a fabric.";
    }
    identity external {
        base fabric-port-role;
        description "The port is used for a fabric to connect
        to outside network.";
    }
    identity access {
        base fabric-port-role;
        description "The port is used for an endpoint to
        connect to a fabric.";
    }

    /*
     * Typedefs
     */
    typedef service-capabilities {
        type enumeration {
            enum ip-mapping {



Zhuang, et al.            Expires June 25, 2018                [Page 11]


Internet-Draft      Data model for DC fabric topology      December 2017


                description "NAT";
                        }
            enum acl-redirect{
                description "Acl redirect, which can provide
                SFC function";
                        }
            enum dynamic-route-exchange{
                description "Dynamic route exchange";
                        }
        }
        description
            "Capability of the device";
    }

    typedef port-type {
        type identityref {
             base port-type;
        }
        description "Port type: ethernet or serial or others.";
    }
    typedef bandwidth {
        type identityref {
             base bandwidth;
        }
        description "Bandwidth of the port.";
    }
    typedef node-ref {
        type instance-identifier;
        description "A reference to a node in topology";
    }

    typedef tp-ref {
        type instance-identifier;
        description "A reference to a termination point in topology";
    }

    typedef link-ref {
        type instance-identifier;
        description "A reference to a link in topology";
    }

    typedef underlay-network-type {
        type identityref {
             base fabric-type;
        }
        description "The type of physical network that implements this
        fabric.Examples are vlan, and trill.";
    }



Zhuang, et al.            Expires June 25, 2018                [Page 12]


Internet-Draft      Data model for DC fabric topology      December 2017


    typedef device-role {
         type identityref {
             base device-role;
        }
        description "Role of the device node.";
    }
    typedef fabric-port-role {
        type identityref {
             base fabric-port-role;
        }
        description "Role of the port in a fabric.";
    }

    typedef fabric-port-type {
        type enumeration {
            enum layer2interface {
                description "L2 interface";
            }
            enum layer3interface {
                description "L3 interface";
            }
            enum layer2Tunnel {
                description "L2 tunnel";
            }
            enum layer3Tunnel {
                description "L3 tunnel";
            }
        }
                description
            "Fabric port type";
    }

    grouping fabric-port {
        description
            "Attributes of a fabric port.";
        leaf name {
            type string;
            description "Name of the port.";
        }
        leaf role {
            type fabric-port-role;
            description "Role of the port in a fabric.";
        }
        leaf type {
            type fabric-port-type;
            description "Type of the port";
        }
        leaf device-port {



Zhuang, et al.            Expires June 25, 2018                [Page 13]


Internet-Draft      Data model for DC fabric topology      December 2017


            type tp-ref;
            description "The device port it mapped to.";
        }
        choice tunnel-option {
            description "Tunnel options to connect two fabrics.
            It could be L2 Tunnel or L3 Tunnel.";
        }
    }
}
<CODE ENDS>

<CODE BEGINS> file "ietf-dc-fabric-topology@2017-12-21.yang"
    module ietf-dc-fabric-topology {

    yang-version 1.1;
    namespace "urn:ietf:params:xml:ns:yang:ietf-dc-fabric-topology";
    prefix fabric;

    import ietf-network {
        prefix nw;

        reference
        "draft-ietf-i2rs-yang-network-topo-20
        NOTE TO RFC EDITOR:
        (1) Please replace above reference to
        draft-ietf-i2rs-yang-network-topo-20 with RFC
        number when published (i.e. RFC xxxx).
        (2) Please replace the date in the revision statement with the
         date of publication when published.";
    }

    import ietf-network-topology {
        prefix nt;

        reference
        "draft-ietf-i2rs-yang-network-topo-20
        NOTE TO RFC EDITOR:
        (1) Please replace above reference to
        draft-ietf-i2rs-yang-network-topo-20 with RFC
        number when published (i.e. RFC xxxx).
        (2) Please replace the date in the revision statement with the
         date of publication when published.";
    }

    import ietf-dc-fabric-types {
        prefix fabrictypes;

        reference



Zhuang, et al.            Expires June 25, 2018                [Page 14]


Internet-Draft      Data model for DC fabric topology      December 2017


        "draft-ietf-i2rs-yang-dc-fabric-network-topology-03
        NOTE TO RFC EDITOR:
         (1) Please replace above reference to draft-ietf-i2rs-yang-dc
         -fabric-network-topology-03 with RFC number when publised
         (i.e. RFC xxxx).
         (2) Please replace the data in the revision statement with the
         data of publication when published.";
    }

    organization
    "IETF I2RS (Interface to the Routing System) Working Group";

    contact
    "WG Web:    <http://tools.ietf.org/wg/i2rs/ >
     WG List:   <mailto:i2rs@ietf.org>

     Editor:    Yan Zhuang
                <mailto:zhuangyan.zhuang@huawei.com>

     Editor:    Danian Shi
                <mailto:shidanian@huawei.com>";


    description
       "This module contains a collection of YANG definitions for Fabric.

        Copyright (c) 2016 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
        (http://trustee.ietf.org/license-info).

        This version of this YANG module is part of
        draft-ietf-i2rs-yang-dc-fabric-network-topology;see the RFC
        itself for full legal notices.

        NOTE TO RFC EDITOR: Please replace above reference to
        draft-ietf-i2rs-yang-dc-fabric-network-topology-03 with RFC
        number when published (i.e. RFC xxxx).";

        revision "2017-12-21"{
        description
             "Initial revision.
              NOTE TO RFC EDITOR: Please replace the following reference



Zhuang, et al.            Expires June 25, 2018                [Page 15]


Internet-Draft      Data model for DC fabric topology      December 2017


              to draft-ietf-i2rs-yang-dc-fabric-network-topology-03 with
              RFC number when published (i.e. RFC xxxx).";
        reference
            "draft-ietf-i2rs-yang-dc-fabric-network-topology-03";
    }

    identity fabric-context {
        description
           "Identity of fabric context";
    }

    typedef fabric-id {
        type nw:node-id;
        description
            "An identifier for a fabric in a topology.
            The identifier is generated by compose-fabric RPC.";
    }

    //grouping statements
    grouping fabric-network-type {
        description "Identify the topology type to be fabric.";
        container fabric-network {
            presence "indicates fabric Network";
        description
          "The presence of the container node indicates fabric topology";
      }
    }

    grouping fabric-options {
        description "Options for a fabric";

        leaf gateway-mode {
            type enumeration {
                enum centralized {
                    description "The Fabric uses centerilized gateway, in
                    which gateway is deployed on SPINE node.";
                }
                enum distributed {
                    description "The Fabric uses distributed gateway, in
                    which gateway is deployed on LEAF node.";
                }
            }
            default "distributed";
            description "Gateway mode of the fabric";
        }

        leaf traffic-behavior {
            type enumeration {



Zhuang, et al.            Expires June 25, 2018                [Page 16]


Internet-Draft      Data model for DC fabric topology      December 2017


                enum normal {
                    description "Normal";
                }
                enum policy-driven {
                    description "Policy driven";
                }
            }
            default "normal";
            description "Traffic behavior of the fabric";
        }

        leaf-list capability-supported {
            type fabrictypes:service-capabilities;
            description
               "Supported services of the fabric";
        }
    }

    grouping device-attributes {
        description "device attributes";
        leaf device-ref {
            type fabrictypes:node-ref;
            description
                "The device the fabric includes.";
        }
        leaf role {
            type fabrictypes:device-role;
            default fabrictypes:leaf;
            description
                "Role of the device node";
        }
    }

    grouping link-attributes {
                description "Link attributes";
        leaf link-ref {
            type fabrictypes:link-ref;
            description
                "The link it includes";
        }
    }

    grouping port-attributes {
        description "Port attributes";
        leaf port-ref {
            type fabrictypes:tp-ref;
            description
                "The port it refers to.";



Zhuang, et al.            Expires June 25, 2018                [Page 17]


Internet-Draft      Data model for DC fabric topology      December 2017


        }
        leaf port-type {
            type fabrictypes:port-type;
            description
                "Port type: ethernet or serial or others.";
        }
        leaf bandwidth {
            type fabrictypes:bandwidth;
            description
                "Bandwidth of the port.";
        }
    }

    grouping fabric-attributes {
        description "Attributes of a fabric";

        leaf fabric-id {
            type fabric-id;
            description
                "Fabric id";
        }

        leaf name {
            type string;
            description
                "Name of the fabric";
        }

        leaf type {
            type fabrictypes:underlay-network-type;
            description
                "The type of physical network that implements this
                 fabric.Examples are vlan, and trill.";
        }

        container vni-capacity {
            description "Number of vnis that the fabric has";
            leaf min {
                type int32;
                description
                    "Vni min capacity";
            }

            leaf max {
                type int32;
                description
                    "Vni max capacity";
            }



Zhuang, et al.            Expires June 25, 2018                [Page 18]


Internet-Draft      Data model for DC fabric topology      December 2017


        }

        leaf description {
            type string;
            description
                "Description of the fabric";
        }

        container options {
            description "Options of the fabric";
            uses fabric-options;
        }

        list device-nodes {
            key device-ref;
            description "Device nodes that include in a fabric.";
            uses device-attributes;
        }

        list device-links {
            key link-ref;
            description "Links that include within a fabric.";
            uses link-attributes;
        }

        list device-ports {
            key port-ref;
            description "Ports that include in the fabric.";
            uses port-attributes;
        }

    }

        // augment statements

    augment "/nw:networks/nw:network/nw:network-types" {
    description
        "Introduce new network type for Fabric-based logical topology";

        uses fabric-network-type;
        }

    augment "/nw:networks/nw:network/nw:node" {
        when "/nw:networks/nw:network/nw:network-types/fabric:fabric-network" {
        description
          "Augmentation parameters apply only for networks
           with fabric topology";
      }



Zhuang, et al.            Expires June 25, 2018                [Page 19]


Internet-Draft      Data model for DC fabric topology      December 2017


        description "Augmentation for fabric nodes created by faas.";

        container fabric-attributes {
                        description
                        "Attributes for a fabric network";

            uses fabric-attributes;
        }
    }

    augment "/nw:networks/nw:network/nw:node/nt:termination-point" {
        when "/nw:networks/nw:network/nw:network-types/fabric:fabric-network" {
        description
          "Augmentation parameters apply only for networks
           with fabric topology";
      }
        description "Augmentation for port on fabric.";

        container fport-attributes {
            config false;
            description
               "Attributes for fabric ports";
            uses fabrictypes:fabric-port;
        }
    }
}
<CODE ENDS>

5.  IANA Considerations

   This document registers the following namespace URIs in the "IETF XML
   Registry" [RFC3688]:

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

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

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

   This document registers the following YANG modules in the "YANG
   Module Names" registry [RFC6020]:






Zhuang, et al.            Expires June 25, 2018                [Page 20]


Internet-Draft      Data model for DC fabric topology      December 2017


   NOTE TO THE RFC EDITOR: In the list below, please replace references
   to "draft-ietf-i2rs-yang-dc-fabric-network-topology-03 (RFC form)"
   with RFC number when published (i.e.  RFC xxxx).

   Name: ietf-dc-fabric-types Namespace:
   urn:ietf:params:xml:ns:yang:ietf-dc-fabric-types Prefix: fabrictypes
   Reference: draft-ietf-i2rs-yang-dc-fabric-network-topology-03.txt
   (RFC form)

   Name: ietf-dc-fabric-topology Namespace:
   urn:ietf:params:xml:ns:yang:ietf-dc-fabric-topology Prefix: fabric
   Reference: draft-ietf-i2rs-yang-dc-fabric-network-topology-03.txt
   (RFC form)

   Name: ietf-dc-fabric-topology-state Namespace:
   urn:ietf:params:xml:ns:yang:ietf-dc-fabric-topology-state Prefix:
   sfabric Reference: draft-ietf-i2rs-yang-dc-fabric-network-topology-
   03.txt (RFC form)

6.  Security Considerations

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

   The NETCONF access control model [RFC6536] 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.These are the subtrees and data nodes and
   their sensitivity/vulnerability in the ietf-dc-fabric-topology
   module:

   fabric-attributes: A malicious client could attempt to sabotage the
   configuration of important fabric attributes, such as device-nodes,
   type.

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

   fport-attributes: A malicious client could attempt to read the
   connections of fabrics without permission, such as device-port, name.



Zhuang, et al.            Expires June 25, 2018                [Page 21]


Internet-Draft      Data model for DC fabric topology      December 2017


7.  Acknowledgements

   We wish to acknowledge the helpful contributions, comments, and
   suggestions that were received from Alexander Clemm, Xufeng Liu,
   Susan Hares, Wei Song, Luis M.  Contreras and Benoit Claise.

8.  References

8.1.  Normative References

   [I-D.draft-ietf-i2rs-yang-l3-topology]
              Clemm, A., Medved, J., Tkacik, T., Liu, X., Bryskin, I.,
              Guo, A., Ananthakrishnan, H., Bahadur, N., and V. Beeram,
              "A YANG Data Model for Layer 3 Topologies", I-D draft-
              ietf-i2rs-yang-l3-topology-04, September 2016.

   [I-D.draft-ietf-i2rs-yang-network-topo]
              Clemm, A., Medved, J., Tkacik, T., Varga, R., Bahadur, N.,
              and H. Ananthakrishnan, "A YANG Data Model for Network
              Topologies", I-D draft-ietf-i2rs-yang-network-topo-06,
              September 2016.

   [I-D.draft-ietf-netmod-revised-datastores-06]
              Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "A Revised Conceptual Model for YANG
              Datastores", I-D draft-ietf-netmod-revised-datastores-06,
              October 2017.

   [I-D.draft-ietf-nvo3-vxlan-gpe]
              Maino, F., Kreeger, L., and U. Elzur, "Generic Protocol
              Extension for VXLAN", I-D draft-ietf-i2rs-yang-network-
              topo-02, October 2016.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <http://www.rfc-editor.org/info/rfc2119>.

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

   [RFC6020]  Bjorklund, M., "YANG - A Data Modeling Language for the
              Network Configuration Protocol (NETCONF)", RFC 6020,
              October 2010.






Zhuang, et al.            Expires June 25, 2018                [Page 22]


Internet-Draft      Data model for DC fabric topology      December 2017


   [RFC6241]  Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
              Bierman, "Network Configuration Protocol (NETCONF)", June
              2011, <http://www.rfc-editor.org/info/rfc6241>.

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

   [RFC6536]  Bierman, A. and B. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", March 2012,
              <http://www.rfc-editor.org/info/rfc6536>.

   [RFC6991]  Schoenwaelder, J., "Common YANG Data Types", RFC 6991,
              July 2013.

   [RFC7950]  Bjorklund, M., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, Auguest 2016.

   [RFC8040]  Bierman, A., Bjorklund, B., and K. Watsen, "RESTCONF
              Protocol", Jan 2017,
              <http://www.rfc-editor.org/info/rfc8040>.

8.2.  Informative References

   [I-D.draft-ietf-i2rs-usecase-reqs-summary]
              Hares, S. and M. Chen, "Summary of I2RS Use Case
              Requirements", I-D draft-ietf-i2rs-usecase-reqs-summary-
              01, May 2015.

Appendix A.  Non NMDA -state modules

   The YANG module ietf-fabric-toplogy defined in this document augments
   two modules, ietf-network and ietf-network-topology, that are
   designed to be used in conjunction with implementations that support
   the Network Management Datastore Architecture (NMDA) defined in [I-
   D.draft-ietf-netmod-revised-datastores].  In order to allow
   implementations to use the model even in case when NMDA is not
   supported, a set of companion modules have been defined that
   represent a state model of networks and network topologies, ietf-
   network-state and ietf-network-topology-state, respectively.

   In order to be able to use the model for fabric topologies defined in
   this in this document in conjunction with non-NMDA compliant
   implementations, a corresponding companion module needs to be
   introduced as well.  This companion module, ietf-fabric-topology-
   state, mirrors ietf-fabric-topology.  However, the module augments
   ietf-network-state (instead of ietf-network and ietf-network-
   topology) and all of its data nodes are non-configurable.



Zhuang, et al.            Expires June 25, 2018                [Page 23]


Internet-Draft      Data model for DC fabric topology      December 2017


   Like ietf-network-state and ietf-network-topology-state, ietf-fabric-
   topology-state SHOULD NOT be supported by implementations that
   support NMDA.  It is for this reason that the module is defined in
   the Appendix.

   The definition of the module follows below.  As the structure of the
   module mirrors that of its underlying module, the YANG tree is not
   depicted separately.

    <CODE BEGINS> file "ietf-dc-fabric-topology-state@2017-12-21.yang"
    module ietf-dc-fabric-topology-state {

    yang-version 1.1;
    namespace "urn:ietf:params:xml:ns:yang:ietf-dc-fabric-topology-state";
    prefix sfabric;

    import ietf-network-state {
        prefix nws;
        reference
        "draft-ietf-i2rs-yang-network-topo-20
        NOTE TO RFC EDITOR:
        (1) Please replace above reference to
        draft-ietf-i2rs-yang-network-topo-20 with RFC
        number when published (i.e. RFC xxxx).
        (2) Please replace the date in the revision statement with the
         date of publication when published.";
    }
    import ietf-dc-fabric-types {
        prefix fabrictypes;

        reference
        "draft-ietf-i2rs-yang-dc-fabric-network-topology-03
        NOTE TO RFC EDITOR:
        (1) Please replace above reference to draft-ietf-i2rs-yang-dc
        -fabric-network-topology-03 with RFC number when published
        (i.e. RFC xxxx).
        (2) Please replace the data in the revision statement with the
        data of publication when published.";
    }
    import ietf-dc-fabric-topology {
        prefix fabric;

        reference
        "draft-ietf-i2rs-yang-dc-fabric-network-topology-03
         NOTE TO RFC EDITOR:
         (1) Please replace above reference to draft-ietf-i2rs-yang-dc
         -fabric-network-topology-03 with RFC number when published
         (i.e. RFC xxxx).



Zhuang, et al.            Expires June 25, 2018                [Page 24]


Internet-Draft      Data model for DC fabric topology      December 2017


         (2) Please replace the data in the revision statement with the
         data of publication when published.";
    }

    organization
    "IETF I2RS (Interface to the Routing System) Working Group";

    contact
    "WG Web:    <http://tools.ietf.org/wg/i2rs/ >
     WG List:   <mailto:i2rs@ietf.org>

     Editor:    Yan Zhuang
                <mailto:zhuangyan.zhuang@huawei.com>

     Editor:    Danian Shi
                <mailto:shidanian@huawei.com>";


    description
        "This module contains a collection of YANG definitions
        for Fabric state, representing topology that is either
        learned, or topology that results from applying toplogy
        that has been configured per the ietf-dc-fabric-topology
        model, mirroring the corresponding data nodes in this model.

        This model mirrors the configuration tree of
        ietf-dc-fabric-topology, but contains only read-only state
        data. The model is not needed when the implemtation
        infrastructure supports the Network Management Datastore
        Architecture(NMDA).

        Copyright (c) 2016 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(http://trustee.ietf.org/license-info).

        This version of this YANG module is part of
        draft-ietf-i2rs-yang-dc-fabric-network-topology;see the RFC
        itself for full legal notices.

        NOTE TO RFC EDITOR: Please replace above reference to
        draft-ietf-i2rs-yang-dc-fabric-network-topology-03 with RFC number
        when published (i.e. RFC xxxx).";




Zhuang, et al.            Expires June 25, 2018                [Page 25]


Internet-Draft      Data model for DC fabric topology      December 2017


    revision "2017-12-21" {
        description
            "Initial revision.
             NOTE TO RFC EDITOR: Please replace the following reference to
             draft-ietf-i2rs-yang-dc-fabric-network-topology-03 with RFC
             number when published (i.e. RFC xxxx).";
        reference
            "draft-ietf-i2rs-yang-dc-fabric-network-topology-03";
    }

    //grouping statements
    grouping fabric-network-type {
      description "Identify the topology type to be fabric.";
      container fabric-network {
         presence "indicates fabric Network";
         description
          "The presence of the container node indicates fabric Topology";
        }
    }

    grouping fabric-options {
      description "Options for a fabric";
      leaf gateway-mode {
        type enumeration {
          enum centralized {
            description "The Fabric uses centerilized gateway, in which
            gateway is deployed on SPINE node.";
          }
          enum distributed {
            description "The Fabric uses distributed gateway, in which
            gateway is deployed on LEAF node.";
          }
        }
        default "distributed";
        description "Gateway mode of the fabric";
      }

      leaf traffic-behavior {
        type enumeration {
          enum normal {
            description "Normal";
          }
          enum policy-driven {
            description "Policy driven";
          }
        }
        default "normal";
        description "Traffic behavior of the fabric";



Zhuang, et al.            Expires June 25, 2018                [Page 26]


Internet-Draft      Data model for DC fabric topology      December 2017


      }

      leaf-list capability-supported {
        type fabrictypes:service-capabilities;
        description
          "Supported services of the fabric";
      }
    }

    grouping device-attributes {
      description "device attributes";
      leaf device-ref {
        type fabrictypes:node-ref;
        description "The device the fabric includes.";
      }
      leaf role {
        type fabrictypes:device-role;
        default fabrictypes:leaf;
        description "Role of the node";
      }
    }

    grouping link-attributes {
      description "Link attributes";
      leaf link-ref {
        type fabrictypes:link-ref;
        description "The link it includes";
      }
    }

    grouping port-attributes {
      description "Port attributes";
      leaf port-ref {
        type fabrictypes:tp-ref;
        description "The port it refers to.";
      }
      leaf port-type {
        type fabrictypes:port-type;
        description
          "Port type: ethernet or serial or others";
        }
      leaf bandwidth {
        type fabrictypes:bandwidth;
        description "Bandwidth of the port";
      }
    }

    grouping fabric-attributes {



Zhuang, et al.            Expires June 25, 2018                [Page 27]


Internet-Draft      Data model for DC fabric topology      December 2017


      description "Attributes of a fabric";
      leaf fabric-id {
        type fabric:fabric-id;
        description "Fabric id";
      }
      leaf name {
        type string;
        description     "Name of the fabric";
      }
      leaf type {
        type fabrictypes:underlay-network-type;
         description
          "The type of physical network that implements this
          fabric.Examples are vlan, and trill.";
        }
      container vni-capacity {
        description "Number of vnis the fabric has";
          leaf min {
            type int32;
            description "Vni min capacity";
          }
          leaf max {
            type int32;
            description "Vni max capacity";
          }
      }
      leaf description {
        type string;
        description "Description of the fabric";
      }
      container options {
        description "Options of the fabric";
        uses fabric-options;
      }
      list device-nodes {
        key device-ref;
        description "Device nodes that include in a fabric.";
        uses device-attributes;
      }
      list device-links {
        key link-ref;
        description "Links that include within a fabric.";
        uses link-attributes;
      }
      list device-ports {
        key port-ref;
        description "Ports that include in the fabric.";
        uses port-attributes;



Zhuang, et al.            Expires June 25, 2018                [Page 28]


Internet-Draft      Data model for DC fabric topology      December 2017


      }
    }

    // augment statements

    augment "/nws:networks/nws:network/nws:network-types" {
      description
        "Introduce new network type for Fabric-based logical topology";
      uses fabric-network-type;
    }

    augment "/nws:networks/nws:network/nws:node" {
      when "/nws:networks/nws:network/nws:network-types/sfabric:fabric-network" {
        description "Augmentation parameters apply only for networks with
        fabric topology.";
      }
      description "Augmentation for fabric nodes.";
      container fabric-attributes-state {
        description
          "Attributes for a fabric network";
        uses fabric-attributes;
      }
    }
}
<CODE ENDS>

Authors' Addresses

   Yan Zhuang
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: zhuangyan.zhuang@huawei.com


   Danian Shi
   Huawei
   101 Software Avenue, Yuhua District
   Nanjing, Jiangsu  210012
   China

   Email: shidanian@huawei.com







Zhuang, et al.            Expires June 25, 2018                [Page 29]


Internet-Draft      Data model for DC fabric topology      December 2017


   Rong Gu
   China Mobile
   32 Xuanwumen West Ave, Xicheng District
   Beijing, Beijing  100053
   China

   Email: gurong_cmcc@outlook.com


   Hariharan Ananthakrishnan
   Packet Design

   Email: hari@packetdesign.com






































Zhuang, et al.            Expires June 25, 2018                [Page 30]


Html markup produced by rfcmarkup 1.129c, available from https://tools.ietf.org/tools/rfcmarkup/