Network Working Group                                         A. Bierman
Internet-Draft                                                 YumaWorks
Intended status: Standards Track                            M. Bjorklund
Expires: April 19, 2018                                   Tail-f Systems
                                                                 J. Dong
                                                     Huawei Technologies
                                                            D. Romascanu
                                                        October 16, 2017


               A YANG Data Model for Hardware Management
                      draft-ietf-netmod-entity-05

Abstract

   This document defines a YANG data model for the management of
   hardware on a single server.

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 http://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, 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
   (http://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




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

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
     1.1.  Terminology . . . . . . . . . . . . . . . . . . . . . . .   2
       1.1.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . .   3
   2.  Objectives  . . . . . . . . . . . . . . . . . . . . . . . . .   3
   3.  Hardware Data Model . . . . . . . . . . . . . . . . . . . . .   4
     3.1.  The Components Lists  . . . . . . . . . . . . . . . . . .   5
   4.  Relationship to ENTITY-MIB  . . . . . . . . . . . . . . . . .   5
   5.  Relationship to ENTITY-SENSOR-MIB . . . . . . . . . . . . . .   6
   6.  Relationship to ENTITY-STATE-MIB  . . . . . . . . . . . . . .   7
   7.  Hardware YANG Module  . . . . . . . . . . . . . . . . . . . .   7
   8.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  35
     8.1.  URI Registrations . . . . . . . . . . . . . . . . . . . .  35
     8.2.  YANG Module Registrations . . . . . . . . . . . . . . . .  35
   9.  Security Considerations . . . . . . . . . . . . . . . . . . .  36
   10. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  37
   11. Normative References  . . . . . . . . . . . . . . . . . . . .  37
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  38

1.  Introduction

   This document defines a YANG [RFC7950] data model for the management
   of hardware on a single server.

   The data model includes configuration and system state (status
   information and counters for the collection of statistics).

1.1.  Terminology

   The keywords "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].

   The following terms are defined in
   [I-D.ietf-netmod-revised-datastores] and are not redefined here:

   o  client

   o  server

   o  configuration

   o  system state



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   o  operational state

   o  intended configuration

1.1.1.  Tree Diagrams

   A simplified graphical representation of the data model is used in
   this document.  The meaning of the symbols in these diagrams is as
   follows:

   o  Brackets "[" and "]" enclose list keys.

   o  Abbreviations before data node names: "rw" means configuration
      data (read-write) and "ro" state data (read-only).

   o  Symbols after data node names: "?" means an optional node, "!"
      means a presence container, and "*" denotes a list and leaf-list.

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

2.  Objectives

   This section describes some of the design objectives for the hardware
   model.

   o  There are many common properties used to identify hardware
      components, which need to be supported in the hardware data model.

   o  There are many important information and states about the
      components, which needs to be collected from the devices which
      support the hardware data model.

   o  The hardware data model SHOULD be suitable for new implementations
      to use as is.

   o  The hardware data model defined in this document can be
      implemented on a system that also implements ENTITY-MIB, thus the
      mapping between the hardware data model and ENTITY-MIB SHOULD be
      clear.

   o  The data model should support pre-provisioning of hardware
      components.





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3.  Hardware Data Model

   This document defines the YANG module "ietf-hardware", which has the
   following structure:

   module: ietf-hardware
       +--rw hardware
          +--ro last-change?   yang:date-and-time
          +--rw component* [name]
             +--rw name              string
             +--rw class             identityref
             +--ro physical-index?   int32 {entity-mib}?
             +--ro description?      string
             +--rw parent?           -> ../../component/name
             +--rw parent-rel-pos?   int32
             +--ro contains-child*   -> ../../component/name
             +--ro hardware-rev?     string
             +--ro firmware-rev?     string
             +--ro software-rev?     string
             +--ro serial-num?       string
             +--rw mfg-name?         string
             +--ro model-name?       string
             +--rw alias?            string
             +--rw asset-id?         string
             +--ro is-fru?           boolean
             +--ro mfg-date?         yang:date-and-time
             +--rw uri*              inet:uri
             +--ro uuid?             yang:uuid
             +--rw state {hardware-state}?
             |  +--ro state-last-changed?   yang:date-and-time
             |  +--rw admin-state?          admin-state
             |  +--ro oper-state?           oper-state
             |  +--ro usage-state?          usage-state
             |  +--ro alarm-state?          alarm-state
             |  +--ro standby-state?        standby-state
             +--ro sensor-data {hardware-sensor}?
                +--ro value?               sensor-value
                +--ro value-type?          sensor-value-type
                +--ro value-scale?         sensor-value-scale
                +--ro value-precision?     sensor-value-precision
                +--ro oper-status?         sensor-status
                +--ro units-display?       string
                +--ro value-timestamp?     yang:date-and-time
                +--ro value-update-rate?   uint32

     notifications:
       +---n hardware-state-change
       +---n hardware-state-oper-enabled {hardware-state}?



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       |  +--ro name?          -> /hardware/component/name
       |  +--ro admin-state?   -> /hardware/component/state/admin-state
       |  +--ro alarm-state?   -> /hardware/component/state/alarm-state
       +---n hardware-state-oper-disabled {hardware-state}?
          +--ro name?          -> /hardware/component/name
          +--ro admin-state?   -> /hardware/component/state/admin-state
          +--ro alarm-state?   -> /hardware/component/state/alarm-state

3.1.  The Components Lists

   The data model for hardware presented in this document uses a flat
   list of components.  Each component in the list is identified by its
   name.  Furthermore, each component has a mandatory "class" leaf.

   The "iana-hardware" module defines YANG identities for the hardware
   types in the IANA-maintained "IANA-ENTITY-MIB" registry.

   The "class" leaf is a YANG identity that describes the type of the
   hardware.  Vendors are encouraged to either directly use one of the
   common IANA-defined identities, or derive a more specific identity
   from one of them.

4.  Relationship to ENTITY-MIB

   If the device implements the ENTITY-MIB [RFC6933], each entry in the
   "/hardware-state/component" list is mapped to one EntPhysicalEntry.
   Objects that are writable in the MIB are mapped to nodes in the
   "/hardware/component" list.

   The "physical-index" leaf MUST contain the value of the corresponding
   entPhysicalEntry's entPhysicalIndex.

   The "class" leaf is mapped to both entPhysicalClass and
   entPhysicalVendorType.  If the value of the "class" leaf is an
   identity that is either derived from or is one of the identities in
   the "iana-hardware" module, then entPhysicalClass contains the
   corresponding IANAPhysicalClass enumeration value.  Otherwise,
   entPhysicalClass contains the IANAPhysicalClass value "other(1)".
   Vendors are encouraged to define an identity (derived from an
   identity in "iana-hardware" if possible) for each enterprise-specific
   registration identifier used for entPhysicalVendorType, and use that
   identity for the "class" leaf.

   The following tables list the YANG data nodes with corresponding
   objects in the ENTITY-MIB.






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   +--------------------------------+----------------------------------+
   | YANG data node in              | ENTITY-MIB object                |
   | /hardware/component            |                                  |
   +--------------------------------+----------------------------------+
   | name                           | entPhysicalName                  |
   | class                          | entPhysicalClass                 |
   |                                | entPhysicalVendorType            |
   | physical-index                 | entPhysicalIndex                 |
   | description                    | entPhysicalDescr                 |
   | parent                         | entPhysicalContainedIn           |
   | parent-rel-pos                 | entPhysicalParentRelPos          |
   | contains-child                 | entPhysicalChildIndex            |
   | hardware-rev                   | entPhysicalHardwareRev           |
   | firmware-rev                   | entPhysicalFirmwareRev           |
   | software-rev                   | entPhysicalSoftwareRev           |
   | serial-num                     | entPhysicalSerialNum             |
   | mfg-name                       | entPhysicalMfgName               |
   | model-name                     | entPhysicalModelName             |
   | alias                          | entPhysicalAlias                 |
   | asset-id                       | entPhysicalAssetID               |
   | is-fru                         | entPhysicalIsFRU                 |
   | mfg-date                       | entPhysicalMfgDate               |
   | uri                            | entPhysicalUris                  |
   | uuid                           | entPhysicalUUID                  |
   +--------------------------------+----------------------------------+

              YANG Data Nodes and Related ENTITY-MIB Objects

5.  Relationship to ENTITY-SENSOR-MIB

   If the device implements the ENTITY-SENSOR-MIB [RFC3433], each entry
   in the "/hardware/component" list where the container "sensor-data"
   exists is mapped to one EntPhySensorEntry.


















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   +-------------------------------------+-----------------------------+
   | YANG data node in                   | ENTITY-SENSOR-MIB object    |
   | /hardware/component/sensor-data     |                             |
   +-------------------------------------+-----------------------------+
   | value                               | entPhySensorValue           |
   | value-type                          | entPhySensorType            |
   | value-scale                         | entPhySensorScale           |
   | value-precision                     | entPhySensorPrecision       |
   | oper-status                         | entPhySensorOperStatus      |
   | units-display                       | entPhySensorUnitsDisplay    |
   | value-timestamp                     | entPhySensorValueTimeStamp  |
   | value-update-rate                   | entPhySensorValueUpdateRate |
   +-------------------------------------+-----------------------------+

           YANG Data Nodes and Related ENTITY-SENSOR-MIB Objects

6.  Relationship to ENTITY-STATE-MIB

   If the device implements the ENTITY-STATE-MIB [RFC4268], each entry
   in the "/hardware/component" list where the container "state" exists
   is mapped to one EntStateEntry.

   +------------------------------------------+------------------------+
   | YANG data node in                        | ENTITY-STATE-MIB       |
   | /hardware/component/state                | object                 |
   +------------------------------------------+------------------------+
   | state-last-changed                       | entStateLastChanged    |
   | admin-state                              | entStateAdmin          |
   | oper-state                               | entStateOper           |
   | usage-state                              | entStateUsage          |
   | alarm-state                              | entStateAlarm          |
   | standby-state                            | entStateStandby        |
   +------------------------------------------+------------------------+

           YANG Data Nodes and Related ENTITY-SENSOR-MIB Objects

7.  Hardware YANG Module

   <CODE BEGINS> file "ietf-hardware@2017-10-16.yang"

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

     import ietf-inet-types {
       prefix inet;
     }



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     import ietf-yang-types {
       prefix yang;
     }
     import iana-hardware {
       prefix ianahw;
     }

     organization
       "IETF NETMOD (NETCONF Data Modeling Language) Working Group";

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

        Editor:   Andy Bierman
                  <mailto:andy@yumaworks.com>

        Editor:   Martin Bjorklund
                  <mailto:mbj@tail-f.com>

        Editor:   Jie Dong
                  <mailto:jie.dong@huawei.com>

        Editor:   Dan Romascanu
                  <mailto:dromasca@gmail.com>";

     // RFC Ed.: replace XXXX and YYYY with actual RFC numbers and
     // remove this note.

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

        This data model is designed for the Network Management Datastore
        Architecture defined in RFC YYYY.

        Copyright (c) 2017 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 RFC XXXX; see
        the RFC itself for full legal notices.";



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     // RFC Ed.: update the date below with the date of RFC publication
     // and remove this note.
     revision 2017-10-16 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: A YANG Data Model for Hardware Management";
     }

     /*
      * Features
      */

     feature entity-mib {
       description
         "This feature indicates that the device implements
          the ENTITY-MIB.";
       reference "RFC 6933: Entity MIB (Version 4)";
     }

     feature hardware-state {
       description
         "Indicates the ENTITY-STATE-MIB objects are supported";
       reference "RFC 4268: Entity State MIB";
     }

     feature hardware-sensor {
       description
         "Indicates the ENTITY-SENSOR-MIB objects are supported";
       reference "RFC 3433: Entity Sensor MIB";
     }

     /*
      * Typedefs
      */

     typedef admin-state {
       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report administrative state.";
         }
         enum locked {
           value 2;
           description
             "The resource is administratively prohibited from use.";
         }



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         enum shutting-down {
           value 3;
           description
             "The resource usage is administratively limited to current
              instances of use.";
         }
         enum unlocked {
           value 4;
           description
             "The resource is not administratively prohibited from
              use.";
         }
       }
       description
         "Represents the various possible administrative states.";
       reference "RFC 4268: EntityAdminState";
     }

     typedef oper-state {
       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report its operational state.";
         }
         enum disabled {
           value 2;
           description
             "The resource is totally inoperable.";
         }
         enum enabled {
           value 3;
           description
             "The resource is partially or fully operable.";
         }
         enum testing {
           value 4;
           description
             "The resource is currently being tested and cannot
              therefore report whether it is operational or not.";
         }
       }
       description
         "Represents the possible values of operational states.";
       reference "RFC 4268: EntityOperState";
     }

     typedef usage-state {



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       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report usage state.";
         }
         enum idle {
           value 2;
           description
             "The resource is servicing no users.";
         }
         enum active {
           value 3;
           description
             "The resource is currently in use and it has sufficient
              spare capacity to provide for additional users.";
         }
         enum busy {
           value 4;
           description
             "The resource is currently in use, but it currently has no
              spare capacity to provide for additional users.";
         }
       }
       description
         "Represents the possible values of usage states.";
       reference "RFC 4268, EntityUsageState";
     }

     typedef alarm-state {
       type bits {
         bit unknown {
           position 0;
           description
             "The resource is unable to report alarm state.";
         }
         bit under-repair {
           position 1;
           description
             "The resource is currently being repaired, which, depending
              on the implementation, may make the other values in this
              bit string not meaningful.";
         }
         bit critical {
           position 2;
           description
             "One or more critical alarms are active against the
              resource.";



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         }
         bit major {
           position 3;
           description
             "One or more major alarms are active against the
              resource.";
         }
         bit minor {
           position 4;
           description
             "One or more minor alarms are active against the
              resource.";
         }
         bit warning {
           position 5;
           description
             "One or more warning alarms are active against the
              resource.";
         }
         bit indeterminate {
           position 6;
           description
             "One or more alarms of whose perceived severity cannot be
              determined are active against this resource.";
         }
       }
       description
         "Represents the possible values of alarm states.  An alarm is a
          persistent indication of an error or warning condition.

          When no bits of this attribute are set, then no active alarms
          are known against this component and it is not under repair.";
       reference "RFC 4268: EntityAlarmStatus";
     }

     typedef standby-state {
       type enumeration {
         enum unknown {
           value 1;
           description
             "The resource is unable to report standby state.";
         }
         enum hot-standby {
           value 2;
           description
             "The resource is not providing service, but it will be
              immediately able to take over the role of the resource to
              be backed up, without the need for initialization



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              activity, and will contain the same information as the
              resource to be backed up.";
         }
         enum cold-standby {
           value 3;
           description
             "The resource is to back up another resource, but will not
              be immediately able to take over the role of a resource to
              be backed up, and will require some initialization
              activity.";
         }
         enum providing-service {
           value 4;
           description
             "The resource is providing service.";
         }
       }
       description
         "Represents the possible values of standby states.";
       reference "RFC 4268: EntityStandbyStatus";
     }

     typedef sensor-value-type {
       type enumeration {
         enum other {
           value 1;
           description
             "A measure other than those listed below.";
         }
         enum unknown {
           value 2;
           description
             "An unknown measurement, or arbitrary, relative numbers";
         }
         enum volts-AC {
           value 3;
           description
             "A measure of electric potential (alternating current).";
         }
         enum volts-DC {
           value 4;
           description
             "A measure of electric potential (direct current).";
         }
         enum amperes {
           value 5;
           description
             "A measure of electric current.";



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         }
         enum watts {
           value 6;
           description
             "A measure of power.";
         }
         enum hertz {
           value 7;
           description
             "A measure of frequency.";
         }
         enum celsius {
           value 8;
           description
             "A measure of temperature.";
         }
         enum percent-RH {
           value 9;
           description
             "A measure of percent relative humidity.";
         }
         enum rpm {
           value 10;
           description
             "A measure of shaft revolutions per minute.";
         }
         enum cmm {
           value 11;
           description
             "A measure of cubic meters per minute (airflow).";
         }
         enum truth-value {
           value 12;
           description
             "Value is one of 1 (true) or 2 (false)";
         }
       }
       description
         "A node using this data type represents the sensor measurement
          data type associated with a physical sensor value. The actual
          data units are determined by examining a node of this type
          together with the associated sensor-value-scale node.

          A node of this type SHOULD be defined together with nodes of
          type sensor-value-scale and sensor-value-precision. These
          three types are used to identify the semantics of a node of
          type sensor-value.";
       reference "RFC 3433: EntitySensorDataType";



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     }

     typedef sensor-value-scale {
       type enumeration {
         enum yocto {
           value 1;
           description
             "Data scaling factor of 10^-24.";
         }
         enum zepto {
           value 2;
           description
             "Data scaling factor of 10^-21.";
         }
         enum atto {
           value 3;
           description
             "Data scaling factor of 10^-18.";
         }
         enum femto {
           value 4;
           description
             "Data scaling factor of 10^-15.";
         }
         enum pico {
           value 5;
           description
             "Data scaling factor of 10^-12.";
         }
         enum nano {
           value 6;
           description
             "Data scaling factor of 10^-9.";
         }
         enum micro {
           value 7;
           description
             "Data scaling factor of 10^-6.";
         }
         enum milli {
           value 8;
           description
             "Data scaling factor of 10^-3.";
         }
         enum units {
           value 9;
           description
             "Data scaling factor of 10^0.";



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         }
         enum kilo {
           value 10;
           description
             "Data scaling factor of 10^3.";
         }
         enum mega {
           value 11;
           description
             "Data scaling factor of 10^6.";
         }
         enum giga {
           value 12;
           description
             "Data scaling factor of 10^9.";
         }
         enum tera {
           value 13;
           description
             "Data scaling factor of 10^12.";
         }
         enum exa {
           value 14;
           description
             "Data scaling factor of 10^15.";
         }
         enum peta {
           value 15;
           description
             "Data scaling factor of 10^18.";
         }
         enum zetta {
           value 16;
           description
             "Data scaling factor of 10^21.";
         }
         enum yotta {
           value 17;
           description
             "Data scaling factor of 10^24.";
         }
       }
       description
         "A node using this data type represents a data scaling factor,
          represented with an International System of Units (SI) prefix.
          The actual data units are determined by examining a node of
          this type together with the associated sensor-value-type.




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          A node of this type SHOULD be defined together with nodes of
          type sensor-value-type and sensor-value-precision.  Together,
          associated nodes of these three types are used to identify the
          semantics of a node of type sensor-value.";
       reference "RFC 3433: EntitySensorDataScale";
     }

     typedef sensor-value-precision {
       type int32 {
         range "-8 .. 9";
       }
       description
         "A node using this data type represents a sensor value
          precision range.

          A node of this type SHOULD be defined together with nodes of
          type sensor-value-type and sensor-value-scale.  Together,
          associated nodes of these three types are used to identify the
          semantics of a node of type sensor-value.

          If a node of this type contains a value in the range 1 to 9,
          it represents the number of decimal places in the fractional
          part of an associated sensor-value fixed- point number.

          If a node of this type contains a value in the range -8 to -1,
          it represents the number of accurate digits in the associated
          sensor-value fixed-point number.

          The value zero indicates the associated sensor-value node is
          not a fixed-point number.

          Server implementers must choose a value for the associated
          sensor-value-precision node so that the precision and accuracy
          of the associated sensor-value node is correctly indicated.

          For example, a component representing a temperature sensor
          that can measure 0 degrees to 100 degrees C in 0.1 degree
          increments, +/- 0.05 degrees, would have an
          sensor-value-precision value of '1', an sensor-value-scale
          value of 'units', and an sensor-value ranging from '0' to
          '1000'.  The sensor-value would be interpreted as
          'degrees C * 10'.";
       reference "RFC 3433: EntitySensorPrecision";
     }

     typedef sensor-value {
       type int32 {
         range "-1000000000 .. 1000000000";



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       }
       description
        "A node using this data type represents an sensor value.

         A node of this type SHOULD be defined together with nodes of
         type sensor-value-type, sensor-value-scale, and
         sensor-value-precision.  Together, associated nodes of those
         three types are used to identify the semantics of a node of
         this data type.

         The semantics of a node using this data type are determined by
         the value of the associated sensor-value-type node.

         If the associated sensor-value-type node is equal to 'voltsAC',
         'voltsDC', 'amperes', 'watts', 'hertz', 'celsius', or 'cmm',
         then a node of this type MUST contain a fixed point number
         ranging from -999,999,999 to +999,999,999.  The value
         -1000000000 indicates an underflow error. The value +1000000000
         indicates an overflow error.  The sensor-value-precision
         indicates how many fractional digits are represented in the
         associated sensor-value node.

         If the associated sensor-value-type node is equal to
         'percentRH', then a node of this type MUST contain a number
         ranging from 0 to 100.

         If the associated sensor-value-type node is equal to 'rpm',
         then a node of this type MUST contain a number ranging from
         -999,999,999 to +999,999,999.

         If the associated sensor-value-type node is equal to
         'truth-value', then a node of this type MUST contain either the
         value 1 (true) or the value 2 (false)'.

         If the associated sensor-value-type node is equal to 'other' or
         unknown', then a node of this type MUST contain a number
         ranging from -1000000000 to 1000000000.";
       reference "RFC 3433: EntitySensorValue";
     }

     typedef sensor-status {
       type enumeration {
         enum ok {
           value 1;
           description
             "Indicates that the server can obtain the sensor value.";
         }
         enum unavailable {



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           value 2;
           description
             "Indicates that the server presently cannot obtain the
              sensor value.";
         }
         enum nonoperational {
           value 3;
           description
             "Indicates that the server believes the sensor is broken.
              The sensor could have a hard failure (disconnected wire),
              or a soft failure such as out-of-range, jittery, or wildly
              fluctuating readings.";
         }
       }
       description
         "A node using this data type represents the operational status
          of a physical sensor.";
       reference "RFC 3433: EntitySensorStatus";
     }

     /*
      * Data nodes
      */

     container hardware {
       description
         "Data nodes representing components.

          If the server supports configuration of hardware components,
          then this data model is instantiated in the configuration
          datastores supported by the server.  The leaf-list 'datastore'
          for the module 'ietf-hardware' in the YANG library provides
          this information.";

       leaf last-change {
         type yang:date-and-time;
         config false;
         description
           "The time the '/hardware/component' list changed in the
            operational state.";
       }

       list component {
         key name;
         description
           "List of components.

            When the server detects a new hardware component, it



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            initializes a list entry in the operational state.

            If the server does not support configuration of hardware
            components, list entries in the operational state are
            initialized with values for all nodes as detected by the
            implementation.

            Otherwise, the following procedure is followed:

              1. If there is an entry in the /hardware/component list in
                 the intended configuration with values for the nodes
                 'class', 'parent', 'parent-rel-pos' that are equal to
                 the detected values, then:

              1a. If the configured entry has a value for 'mfg-name'
                  that is equal to the detected value, or if the
                  'mfg-name' value cannot be detected, then the list
                  entry in the operational state is initialized with the
                  configured values for all configured nodes, including
                  the 'name'.

                  Otherwise, the list entry in the operational state is
                  initialized with values for all nodes as detected by
                  the implementation.  The implementation may raise an
                  alarm that informs about the 'mfg-name' mismatch
                  condition.  How this is done is outside the scope of
                  this document.

              1b. Otherwise (i.e., there is no matching configuration
                  entry), the list entry in the operational state is
                  initialized with values for all nodes as detected by
                  the implementation.

            If the /hardware/component list in the intended
            configuration is modified, then the system MUST behave as if
            it re-initializes itself, and follow the procedure in (1).";
         reference "RFC 6933: entPhysicalEntry";

         leaf name {
           type string;
           description
             "The name assigned to this component.

              This name is not required to be the same as
              entPhysicalName.";
         }

         leaf class {



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           type identityref {
             base ianahw:hardware-class;
           }
           mandatory true;
           description
             "An indication of the general hardware type of the
              component.";
           reference "RFC 6933: entPhysicalClass";
         }

         leaf physical-index {
           if-feature entity-mib;
           type int32 {
             range "1..2147483647";
           }
           config false;
           description
             "The entPhysicalIndex for the entPhysicalEntry represented
              by this list entry.";
           reference "RFC 6933: entPhysicalIndex";
         }

         leaf description {
           type string;
           config false;
           description
             "A textual description of component.  This node should
              contain a string that identifies the manufacturer's name
              for the component and should be set to a distinct value
              for each version or model of the component.";
           reference "RFC 6933: entPhysicalDescr";
         }

         leaf parent {
           type leafref {
             path "../../component/name";
             require-instance false;
           }
           description
             "The name of the component that physically contains this
              component.

              If this leaf is not instantiated, it indicates that this
              component is not contained in any other component.

              In the event that a physical component is contained by
              more than one physical component (e.g., double-wide
              modules), this node contains the name of one of these



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              components.  An implementation MUST use the same name
              every time this node is instantiated.";
           reference "RFC 6933: entPhysicalContainedIn";
         }

         leaf parent-rel-pos {
           type int32 {
             range "0 .. 2147483647";
           }
           description
             "An indication of the relative position of this child
              component among all its sibling components.  Sibling
              components are defined as components that:

                o Share the same value of the 'parent' node; and

                o Share a common base identity for the 'class' node.

              Note that the last rule gives implementations flexibility
              in how components are numbered.  For example, some
              implementations might have a single number series for all
              components derived from 'ianahw:port', while some others
              might have different number series for different
              components with identities derived from 'ianahw:port' (for
              example, one for RJ45 and one for SFP).";

           reference "RFC 6933: entPhysicalParentRelPos";
         }

         leaf-list contains-child {
           type leafref {
             path "../../component/name";
           }
           config false;
           description
             "The name of the contained component.";
           reference "RFC 6933: entPhysicalChildIndex";
         }

         leaf hardware-rev {
           type string;
           config false;
           description
             "The vendor-specific hardware revision string for the
              component.  The preferred value is the hardware revision
              identifier actually printed on the component itself (if
              present).";
           reference "RFC 6933: entPhysicalHardwareRev";



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         }

         leaf firmware-rev {
           type string;
           config false;
           description
             "The vendor-specific firmware revision string for the
              component.";
           reference "RFC 6933: entPhysicalFirmwareRev";
         }

         leaf software-rev {
           type string;
           config false;
           description
             "The vendor-specific software revision string for the
              component.";
           reference "RFC 6933: entPhysicalSoftwareRev";
         }

         leaf serial-num {
           type string;
           config false;
           description
             "The vendor-specific serial number string for the
              component.  The preferred value is the serial number
              string actually printed on the component itself (if
              present).";
           reference "RFC 6933: entPhysicalSerialNum";
         }

         leaf mfg-name {
           type string;
           description
             "The name of the manufacturer of this physical component.
              The preferred value is the manufacturer name string
              actually printed on the component itself (if present).

              Note that comparisons between instances of the model-name,
              firmware-rev, software-rev, and the serial-num nodes are
              only meaningful amongst component with the same value of
              mfg-name.

              If the manufacturer name string associated with the
              physical component is unknown to the server, then this
              node is not instantiated.";
           reference "RFC 6933: entPhysicalMfgName";
         }



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         leaf model-name {
           type string;
           config false;
           description
             "The vendor-specific model name identifier string
              associated with this physical component.  The preferred
              value is the customer-visible part number, which may be
              printed on the component itself.

              If the model name string associated with the physical
              component is unknown to the server, then this node is not
              instantiated.";
           reference "RFC 6933: entPhysicalModelName";
         }

         leaf alias {
           type string;
           description
             "An 'alias' name for the component, as specified by a
              network manager, and provides a non-volatile 'handle' for
              the component.

              If no configured value exists, the server MAY set the
              value of this node to a locally unique value in the
              operational state.

              A server implementation MAY map this leaf to the
              entPhysicalAlias MIB object.  Such an implementation needs
              to use some mechanism to handle the differences in size
              and characters allowed between this leaf and
              entPhysicalAlias.  The definition of such a mechanism is
              outside the scope of this document.";
           reference "RFC 6933: entPhysicalAlias";
         }

         leaf asset-id {
           type string;
           description
             "This node is a user-assigned asset tracking identifier for
              the component.

              A server implementation MAY map this leaf to the
              entPhysicalAssetID MIB object.  Such an implementation
              needs to use some mechanism to handle the differences in
              size and characters allowed between this leaf and
              entPhysicalAssetID.  The definition of such a mechanism is
              outside the scope of this document.";
           reference "RFC 6933: entPhysicalAssetID";



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         }

         leaf is-fru {
           type boolean;
           config false;
           description
             "This node indicates whether or not this component is
              considered a 'field replaceable unit' by the vendor.  If
              this node contains the value 'true', then this component
              identifies a field replaceable unit.  For all components
              that are permanently contained within a field replaceable
              unit, the value 'false' should be returned for this
              node.";
           reference "RFC 6933: entPhysicalIsFRU";
         }

         leaf mfg-date {
           type yang:date-and-time;
           config false;
           description
             "The date of manufacturing of the managed component.";
           reference "RFC 6933: entPhysicalMfgDate";
         }

         leaf-list uri {
           type inet:uri;
           description
             "This node contains identification information about the
              component.";
           reference "RFC 6933: entPhysicalUris";
         }

         leaf uuid {
           type yang:uuid;
           config false;
           description
             "A Universally Unique Identifier of the component.";
           reference "RFC 6933: entPhysicalUUID";
         }

         container state {
           if-feature hardware-state;
           description
             "State-related nodes";
           reference "RFC 4268: Entity State MIB";

           leaf state-last-changed {
             type yang:date-and-time;



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             config false;
             description
               "The date and time when the value of any of the
                admin-state, oper-state, usage-state, alarm-state, or
                standby-state changed for this component.

                If there has been no change since the last
                re-initialization of the local system, this node
                contains the date and time of local system
                initialization.  If there has been no change since the
                component was added to the local system, this node
                contains the date and time of the insertion.";
             reference "RFC 4268: entStateLastChanged";
           }

           leaf admin-state {
             type admin-state;
             description
               "The administrative state for this component.

                This node refers to a component's administrative
                permission to service both other components within its
                containment hierarchy as well other users of its
                services defined by means outside the scope of this
                module.

                Some components exhibit only a subset of the remaining
                administrative state values.  Some components cannot be
                locked, and hence this node exhibits only the 'unlocked'
                state.  Other components cannot be shutdown gracefully,
                and hence this node does not exhibit the 'shutting-down'
                state.";
             reference "RFC 4268: entStateAdmin";
           }

           leaf oper-state {
             type oper-state;
             config false;
             description
               "The operational state for this component.

                Note that this node does not follow the administrative
                state.  An administrative state of down does not predict
                an operational state of disabled.

                Note that some implementations may not be able to
                accurately report oper-state while the admin-state node
                has a value other than 'unlocked'.  In these cases, this



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                node MUST have a value of 'unknown'.";
             reference "RFC 4268: entStateOper";
           }

           leaf usage-state {
             type usage-state;
             config false;
             description
               "The usage state for this component.

                This node refers to a component's ability to service
                more components in a containment hierarchy.

                Some components will exhibit only a subset of the usage
                state values.  Components that are unable to ever
                service any components within a containment hierarchy
                will always have a usage state of 'busy'.  Some
                components will only ever be able to support one
                component within its containment hierarchy and will
                therefore only exhibit values of 'idle' and 'busy'.";
             reference "RFC 4268, entStateUsage";
           }

           leaf alarm-state {
             type alarm-state;
             config false;
             description
               "The alarm state for this component.  It does not
                include the alarms raised on child components within its
                containment hierarchy.";
             reference "RFC 4268: entStateAlarm";
           }

           leaf standby-state {
             type standby-state;
             config false;
             description
               "The standby state for this component.

                Some components will exhibit only a subset of the
                remaining standby state values.  If this component
                cannot operate in a standby role, the value of this node
                will always be 'providing-service'.";
             reference "RFC 4268: entStateStandby";
           }
         }

         container sensor-data {



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           when 'derived-from-or-self(../class,
                                      "ianahw:sensor")' {
             description
               "Sensor data nodes present for any component of type
                'sensor'";
           }
           if-feature hardware-sensor;
           config false;

           description
             "Sensor-related nodes.";
           reference "RFC 3433: Entity Sensor MIB";

           leaf value {
             type sensor-value;
             description
               "The most recent measurement obtained by the server
                for this sensor.

                A client that periodically fetches this node should also
                fetch the nodes 'value-type', 'value-scale', and
                'value-precision', since they may change when the value
                is changed.";
             reference "RFC 3433: entPhySensorValue";
           }

           leaf value-type {
             type sensor-value-type;
             description
               "The type of data units associated with the
                sensor value";
             reference "RFC 3433: entPhySensorType";
           }

           leaf value-scale {
             type sensor-value-scale;
             description
               "The (power of 10) scaling factor associated
                with the sensor value";
             reference "RFC 3433: entPhySensorScale";
           }

           leaf value-precision {
             type sensor-value-precision;
             description
               "The number of decimal places of precision
                associated with the sensor value";
             reference "RFC 3433: entPhySensorPrecision";



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           }

           leaf oper-status {
             type sensor-status;
             description
               "The operational status of the sensor.";
             reference "RFC 3433: entPhySensorOperStatus";
           }

           leaf units-display {
             type string;
             description
               "A textual description of the data units that should be
                used in the display of the sensor value.";
             reference "RFC 3433: entPhySensorUnitsDisplay";
           }

           leaf value-timestamp {
             type yang:date-and-time;
             description
               "The time the status and/or value of this sensor was last
                obtained by the server.";
             reference "RFC 3433: entPhySensorValueTimeStamp";
           }

           leaf value-update-rate {
             type uint32;
             units "milliseconds";
             description
               "An indication of the frequency that the server updates
                the associated 'value' node, representing in
                milliseconds.  The value zero indicates:

                 - the sensor value is updated on demand (e.g.,
                   when polled by the server for a get-request),
                 - the sensor value is updated when the sensor
                   value changes (event-driven),
                 - the server does not know the update rate.";
             reference "RFC 3433: entPhySensorValueUpdateRate";
           }
         }
       }
     }

     /*
      * Notifications
      */




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     notification hardware-state-change {
       description
         "A hardware-state-change notification is generated when the
          value of /hardware/last-change changes in the operational
          state.";
       reference "RFC 6933, entConfigChange";
     }

     notification hardware-state-oper-enabled {
       if-feature hardware-state;
       description
         "A hardware-state-oper-enabled notification signifies that a
          component has transitioned into the 'enabled' state.";

       leaf name {
         type leafref {
           path "/hardware/component/name";
         }
         description
           "The name of the component that has transitioned into the
            'enabled' state.";
       }
       leaf admin-state {
         type leafref {
           path "/hardware/component/state/admin-state";
         }
         description
           "The administrative state for the component.";
       }
       leaf alarm-state {
         type leafref {
           path "/hardware/component/state/alarm-state";
         }
         description
           "The alarm state for the component.";
       }
       reference "RFC 4268, entStateOperEnabled";
     }

     notification hardware-state-oper-disabled {
       if-feature hardware-state;
       description
         "A hardware-state-oper-disabled notification signifies that a
          component has transitioned into the 'disabled' state.";

       leaf name {
         type leafref {
           path "/hardware/component/name";



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         }
         description
           "The name of the component that has transitioned into the
            'disabled' state.";
       }
       leaf admin-state {
         type leafref {
           path "/hardware/component/state/admin-state";
         }
         description
           "The administrative state for the component.";
       }
       leaf alarm-state {
         type leafref {
           path "/hardware/component/state/alarm-state";
         }
         description
           "The alarm state for the component.";
       }
       reference "RFC 4268, entStateOperDisabled";
     }

   }

   <CODE ENDS>

   <CODE BEGINS> file "iana-hardware@2017-10-16.yang"

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

     organization "IANA";
     contact
       "        Internet Assigned Numbers Authority

        Postal: ICANN
                4676 Admiralty Way, Suite 330
                Marina del Rey, CA 90292

        Tel:    +1 310 823 9358
        <mailto:iana@iana.org>";


     description
       "IANA defined identities for hardware class.";
     reference



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       // RFC Ed.: replace XXXX with actual path and remove this note.
       "https://www.iana.org/assignments/XXXX";

     // RFC Ed.: replace XXXX with actual RFC number and remove this
     // note.

     // RFC Ed.: update the date below with the date of RFC publication
     // and remove this note.
     revision 2017-10-16 {
       description
         "Initial revision.";
       reference
         "RFC XXXX: A YANG Data Model for Hardware Management";
     }

     /*
      * Identities
      */

     identity hardware-class {
       description
         "This identity is the base for all hardware class
          identifiers.";
     }

     identity unknown {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is unknown
          to the server.";
     }

     identity chassis {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is an
          overall container for networking equipment.  Any class of
          physical component, except a stack, may be contained within a
          chassis; a chassis may only be contained within a stack.";
     }

     identity backplane {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of device for aggregating and forwarding networking traffic,
          such as a shared backplane in a modular ethernet switch.  Note
          that an implementation may model a backplane as a single



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          physical component, which is actually implemented as multiple
          discrete physical components (within a chassis or stack).";
     }

     identity container {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is capable
          of containing one or more removable physical entities,
          possibly of different types.  For example, each (empty or
          full) slot in a chassis will be modeled as a container.  Note
          that all removable physical components should be modeled
          within a container component, such as field-replaceable
          modules, fans, or power supplies.  Note that all known
          containers should be modeled by the agent, including empty
          containers.";
     }

     identity power-supply {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is a
          power-supplying component.";
     }

     identity fan {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is a fan or
          other heat-reduction component.";
     }

     identity sensor {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of sensor, such as a temperature sensor within a router
          chassis.";
     }

     identity module {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of self-contained sub-system.  If a module component is
          removable, then it should be modeled within a container
          component; otherwise, it should be modeled directly within
          another physical component (e.g., a chassis or another



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          module).";
     }

     identity port {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of networking port, capable of receiving and/or transmitting
          networking traffic.";
     }

     identity stack {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of super-container (possibly virtual) intended to group
          together multiple chassis entities.  A stack may be realized
          by a virtual cable, a real interconnect cable attached to
          multiple chassis, or multiple interconnect cables.  A stack
          should not be modeled within any other physical components,
          but a stack may be contained within another stack.  Only
          chassis components should be contained within a stack.";
     }

     identity cpu {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of central processing unit.";
     }

     identity energy-object {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of energy object, i.e., a piece of equipment that is part of
          or attached to a communications network that is monitored,
          controlled, or aids in the management of another device for
          Energy Management.";
     }

     identity battery {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of battery.";
     }




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     identity storage-drive {
       base ianahw:hardware-class;
       description
         "This identity is applicable if the hardware class is some sort
          of component with data storage capability as main
          functionality, e.g., disk drive (HDD), solid state device
          (SSD), hybrid (SSHD), object storage (OSD) or other.";
     }
   }

   <CODE ENDS>

8.  IANA Considerations

   This document defines the initial version of the IANA-maintained
   "iana-hardware" YANG module.

   The "iana-hardware" YANG module is intended to reflect the
   "IANA-ENTITY-MIB" MIB module so that if a new enumeration is added to
   the "IANAPhysicalClass" TEXTUAL-CONVENTION, the same class is added
   as an identity derived from "ianahw:hardware-class".

   When the "iana-hardware" YANG module is updated, a new "revision"
   statement must be added in front of the existing revision statements.

8.1.  URI Registrations

   This document registers two URIs in the IETF XML registry [RFC3688].
   Following the format in RFC 3688, the following registrations are
   requested to be made.

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

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

8.2.  YANG Module Registrations

   This document registers two YANG modules in the YANG Module Names
   registry [RFC6020].








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     name:         iana-hardware
     namespace:    urn:ietf:params:xml:ns:yang:iana-hardware
     prefix:       ianahw
     reference:    RFC XXXX

     name:         ietf-hardware
     namespace:    urn:ietf:params:xml:ns:yang:ietf-hardware
     prefix:       hw
     reference:    RFC XXXX

9.  Security Considerations

   The YANG module defined in this memo is designed to be accessed via
   the NETCONF protocol [RFC6241].  The lowest NETCONF layer is the
   secure transport layer, and the mandatory-to-implement secure
   transport is Secure Shell (SSH) [RFC6242].  The NETCONF access
   control model [RFC6536] provides the means to restrict access for
   particular NETCONF users to a pre-configured subset of all available
   NETCONF protocol operations and content.

   There are a number of data nodes defined in this YANG 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)
   to these data nodes without proper protection can have a negative
   effect on network operations.  These are the subtrees and data nodes
   and their sensitivity/vulnerability:

   /hardware/component/admin-state:  Setting this node to 'locked' or
      'shutting-down' can cause disruption of services ranging from
      those running on a port to those on an entire device, depending on
      the type of component.

   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:

   /hardware/component:  The leafs in this list expose information about
      the physical components in a device, which may be used to identify
      the vendor, model, version, and specific device-identification
      information of each system component.

   /hardware/component/sensor-data/value:  This node may expose the
      values of particular physical sensors in a device.





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   /hardware/component/state:  Access to this node allows one to figure
      out what the active and standby resources in a device are.

10.  Acknowledgments

   The authors wish to thank the following individuals, who all provided
   helpful comments on various draft versions of this document: Bart
   Bogaert, Timothy Carey, William Lupton, Juergen Schoenwaelder.

11.  Normative References

   [I-D.ietf-netmod-revised-datastores]
              Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
              and R. Wilton, "Network Management Datastore
              Architecture", draft-ietf-netmod-revised-datastores-03
              (work in progress), July 2017.

   [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>.

   [RFC3433]  Bierman, A., Romascanu, D., and K. Norseth, "Entity Sensor
              Management Information Base", RFC 3433,
              DOI 10.17487/RFC3433, December 2002, <https://www.rfc-
              editor.org/info/rfc3433>.

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

   [RFC4268]  Chisholm, S. and D. Perkins, "Entity State MIB", RFC 4268,
              DOI 10.17487/RFC4268, November 2005, <https://www.rfc-
              editor.org/info/rfc4268>.

   [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>.



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   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              DOI 10.17487/RFC6536, March 2012, <https://www.rfc-
              editor.org/info/rfc6536>.

   [RFC6933]  Bierman, A., Romascanu, D., Quittek, J., and M.
              Chandramouli, "Entity MIB (Version 4)", RFC 6933,
              DOI 10.17487/RFC6933, May 2013, <https://www.rfc-
              editor.org/info/rfc6933>.

   [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>.

Authors' Addresses

   Andy Bierman
   YumaWorks

   Email: andy@yumaworks.com


   Martin Bjorklund
   Tail-f Systems

   Email: mbj@tail-f.com


   Jie Dong
   Huawei Technologies

   Email: jie.dong@huawei.com


   Dan Romascanu

   Email: dromasca@gmail.com














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