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Entity MIB (Version 4)
RFC 6933

Document Type RFC - Proposed Standard (May 2013) Errata
Obsoletes RFC 4133
Authors Andy Bierman , Dan Romascanu , Juergen Quittek , Mouli Chandramouli
Last updated 2020-01-21
RFC stream Internet Engineering Task Force (IETF)
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IESG Responsible AD Benoît Claise
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RFC 6933
Internet Engineering Task Force (IETF)                        A. Bierman
Request for Comments: 6933                               YumaWorks, Inc.
Obsoletes: 4133                                             D. Romascanu
Category: Standards Track                                          Avaya
ISSN: 2070-1721                                               J. Quittek
                                                         NEC Europe Ltd.
                                                         M. Chandramouli
                                                     Cisco Systems, Inc.
                                                                May 2013

                         Entity MIB (Version 4)

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes managed objects used for managing
   multiple logical and physical entities managed by a single Simple
   Network Management Protocol (SNMP) agent.  This document specifies
   version 4 of the Entity MIB.  This memo obsoletes version 3 of the
   Entity MIB module published as RFC 4133.

Status of This Memo

   This is an Internet Standards Track document.

   This document is a product of the Internet Engineering Task Force
   (IETF).  It represents the consensus of the IETF community.  It has
   received public review and has been approved for publication by the
   Internet Engineering Steering Group (IESG).  Further information on
   Internet Standards is available in Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc6933.

Copyright Notice

   Copyright (c) 2013 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

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   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1. The SNMP Management Framework ...................................3
   2. Overview ........................................................3
      2.1. Terms ......................................................5
      2.2. Relationship to Community Strings ..........................6
      2.3. Relationship to SNMP Contexts ..............................6
      2.4. Relationship to Proxy Mechanisms ...........................6
      2.5. Relationship to a Chassis MIB ..............................7
      2.6. Relationship to the Interfaces MIB .........................7
      2.7. Relationship to the Other MIB Modules ......................7
      2.8. Relationship to Naming Scopes ..............................7
      2.9. Multiple Instances of the Entity MIB .......................8
      2.10. Re-Configuration of Entities ..............................9
      2.11. Textual Convention Change .................................9
      2.12. MIB Structure .............................................9
           2.12.1. entityPhysical Group ..............................10
           2.12.2. entityLogical Group ...............................12
           2.12.3. entityMapping Group ...............................12
           2.12.4. entityGeneral Group ...............................13
           2.12.5. entityNotifications Group .........................13
      2.13. Multiple Agents ..........................................13
      2.14. Changes Since RFC 2037 ...................................14
           2.14.1. Textual Conventions ...............................14
           2.14.2. New entPhysicalTable Objects ......................14
           2.14.3. New entLogicalTable Objects .......................14
           2.14.4. Bug Fixes .........................................14
      2.15. Changes Since RFC 2737 ...................................15
           2.15.1. Textual Conventions ...............................15
           2.15.2. New Objects .......................................15
           2.15.3. Bug Fixes .........................................15
      2.16. Changes Since RFC 4133 ...................................15
           2.16.1. MIB Module Addition ...............................15
           2.16.2. Modification to Some of the MIB Objects ...........15
           2.16.3. New TC for Universally Unique Identifier ..........16
   3. MIB Definitions ................................................16
      3.1. ENTITY-MIB ................................................16
      3.2. IANA-ENTITY-MIB ...........................................50
      3.3. UUID-TC-MIB ...............................................53
   4. Usage Examples .................................................55
      4.1. Router/Bridge .............................................55
      4.2. Repeaters .................................................62
      4.3. EMAN Example ..............................................69
   5. Security Considerations ........................................70

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   6. IANA Considerations ............................................72
   7. Acknowledgements ...............................................73
   8. References .....................................................73
      8.1. Normative References ......................................73
      8.2. Informative References ....................................74

1.  The SNMP Management Framework

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to section 7 of
   RFC 3410 [RFC3410].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through the Simple Network Management Protocol (SNMP).
   Objects in the MIB are defined using the mechanisms defined in the
   Structure of Management Information (SMI).  This memo specifies a MIB
   module that is compliant to the SMIv2, which is described in STD 58,
   RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
   [RFC2580].

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in RFC
   2119 [RFC2119].

2.  Overview

   There is a need for a standardized way of representing a single
   agent, which supports multiple instances of one MIB module.  This is
   presently true for at least 3 standard MIB modules and is likely to
   become true for more and more MIB modules as time passes.  For
   example:

   - multiple instances of a bridge supported within a single device
     that has a single agent;

   - multiple repeaters supported by a single agent; and

   - multiple OSPF backbone areas, each operating as part of its own
     Autonomous System and each identified by the same area-id (e.g.,
     0.0.0.0), supported inside a single router with one agent.

   The single agent present in each of these cases implies a
   relationship binds these entities.  Effectively, there is some
   "overall" physical entity that houses the sum of the things managed
   by that one agent, i.e., there are multiple "logical" entities within
   a single physical entity.  Sometimes, the overall physical entity

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   contains multiple (smaller) physical entities, and each logical
   entity is associated with a particular physical entity.  Sometimes,
   the overall physical entity is a "compound" of multiple physical
   entities (e.g., a stack of stackable hubs).

   What is needed is a way to determine exactly which logical entities
   are managed by the agent (with some version of SNMP) in order to
   communicate with the agent about a particular logical entity.  When
   different logical entities are associated with different physical
   entities within the overall physical entity, it is also useful to be
   able to use this information to distinguish between logical entities.

   In these situations, there is no need for varbinds for multiple
   logical entities to be referenced in the same SNMP message (although
   that might be useful in the future).  Rather, it is sufficient, and
   in some situations preferable, to have the context/community in the
   message identify the logical entity to which the varbinds apply.

   Version 2 of this MIB addresses new requirements that have emerged
   since the publication of the first Entity MIB [RFC2037].  There is a
   need for a standardized way of providing non-volatile,
   administratively assigned identifiers for physical components
   represented with the Entity MIB.  There is also a need to align the
   Entity MIB with the SNMPv3 administrative framework (STD 62,
   [RFC3411]).  Implementation experience has shown that additional
   physical component attributes are also desirable.

   Version 3 of this MIB addresses new requirements that have emerged
   since the publication of the second Entity MIB [RFC2737].  There is a
   need to identify physical entities that are central processing units
   (CPUs) and a need to provide a Textual Convention (TC) that
   identifies an entPhysicalIndex value or zero, where the value zero
   has application-specific semantics.  Two new objects have been added
   to the entPhysicalTable to identify the manufacturing date and
   provide additional URIs for a particular physical entity.

   Version 4 of this MIB addresses new requirements that have emerged
   since the publication of the third version of the Entity MIB
   [RFC4133].  There is a need to add new enumerated values for entity
   physical classes, a need to provide identification information for
   physical entities using a Universally Unique Identifier (UUID)
   format, and a need to have compliant implementations of the Entity
   MIB with a smaller subsets of MIB objects for devices with
   constrained resources.

   The PhysicalClass TEXTUAL-CONVENTION was deprecated, and a new
   IANAPhysicalClass TC (maintained by IANA) was created.  A new TC,
   UUIDorZero, was created to represent a UUID, and a new MIB object was

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   added to the entPhysicalTable to identify an entity.  A new
   compliance statement, entity4CRCompliance, has been added for
   possible implementation of a selected subset of MIB objects by
   entities with constrained resources.

2.1.  Terms

   The following terms are used throughout this document:

   - Naming Scope
     A "naming scope" represents the set of information that may be
     potentially accessed through a single SNMP operation.  All
     instances within the naming scope share the same unique identifier
     space.  For SNMPv1, a naming scope is identified by the value of
     the associated entLogicalCommunity instance.  For SNMPv3, the term
     "context" is used instead of "naming scope".  The complete
     definition of an SNMP context can be found in Section 3.3.1 of RFC
     3411 [RFC3411].

   - Multi-Scoped Object
     A MIB object for which identical instance values identify different
     managed information in different naming scopes is called a "multi-
     scoped" MIB object.

   - Single-Scoped Object
     A MIB object for which identical instance values identify the same
     managed information in different naming scopes is called a "single-
     scoped" MIB object.

   - Logical Entity
     A managed system contains one or more "logical entities", each
     represented by at most one instantiation of each of a particular
     set of MIB objects.  A set of management functions is associated
     with each logical entity.  Examples of logical entities include
     routers, bridges, print-servers, etc.

   - Physical Entity
     A "physical entity" or "physical component" represents an
     identifiable physical resource within a managed system.  Zero or
     more logical entities may utilize a physical resource at any given
     time.  Determining which physical components are represented by an
     agent in the EntPhysicalTable is an implementation-specific matter.
     Typically, physical resources (e.g., communications ports,
     backplanes, sensors, daughter-cards, power supplies, and the
     overall chassis), which can be managed via functions associated
     with one or more logical entities, are included in the MIB.

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   - Containment Tree
     Each physical component may be modeled as 'contained' within
     another physical component.  A "containment-tree" is the conceptual
     sequence of entPhysicalIndex values that uniquely specifies the
     exact physical location of a physical component within the managed
     system.  It is generated by 'following and recording' each
     entPhysicalContainedIn instance 'up the tree towards the root'
     until a value of zero, indicating no further containment, is found.

2.2.  Relationship to Community Strings

   For community-based SNMP, differentiating logical entities is one
   (but not the only) purpose of the community string [RFC1157].  This
   is accommodated by representing each community string as a logical
   entity.

   Note that different logical entities may share the same naming scope
   and, therefore, the same values of entLogicalCommunity.  This is
   possible, providing they have no need for the same instance of a MIB
   object to represent different managed information.

2.3.  Relationship to SNMP Contexts

   Version 2 of the Entity MIB contains support for associating SNMPv3
   contexts with logical entities.  Two new MIB objects, defining an
   SnmpEngineID and ContextName pair, are used together to identify an
   SNMP context associated with a logical entity.  This context can be
   used (in conjunction with the entLogicalTAddress and
   entLogicalTDomain MIB objects) to send SNMPv3 messages on behalf of a
   particular logical entity.

2.4.  Relationship to Proxy Mechanisms

   The Entity MIB is designed to allow functional component discovery.
   The administrative relationships between different logical entities
   are not visible in any Entity MIB tables.  A Network Management
   System (NMS) cannot determine whether MIB instances in different
   naming scopes are realized locally or remotely (e.g., via some proxy
   mechanism) by examining any particular Entity MIB objects.

   The management of administrative framework functions is not an
   explicit goal of the Entity MIB WG at this time.  This new area of
   functionality may be revisited after some operational experience with
   the Entity MIB is gained.

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   Note that for community-based versions of SNMP, a network
   administrator will likely be able to associate community strings with
   naming scopes that have proprietary mechanisms, as a matter of
   configuration.  There are no mechanisms for managing naming scopes
   defined in this MIB.

2.5.  Relationship to a Chassis MIB

   Some readers may recall that a previous IETF working group attempted
   to define a Chassis MIB.  No consensus was reached by that working
   group, possibly because its scope was too broad.  As such, it is not
   the purpose of the ENTITY-MIB module to be a "Chassis MIB
   replacement", nor is it within the scope of the ENTITY-MIB module to
   contain all the information that might be necessary to manage a
   "chassis".  On the other hand, the entities represented by an
   implementation of the ENTITY-MIB module might well be contained in a
   chassis.

2.6.  Relationship to the Interfaces MIB

   The Entity MIB contains a mapping table identifying physical
   components that have 'external values' (e.g., ifIndex) associated
   with them within a given naming scope.  This table can be used to
   identify the physical location of each interface in the ifTable
   [RFC2863].  Because ifIndex values in different contexts are not
   related to one another, the interface-to-physical-component
   associations are relative to the same logical entity within the
   agent.

   The Entity MIB also contains entPhysicalName and entPhysicalAlias
   objects, which approximate the semantics of the ifName and ifAlias
   objects (respectively) from the Interfaces MIB [RFC2863] for all
   types of physical components.

2.7.  Relationship to the Other MIB Modules

   The Entity MIB contains a mapping table identifying physical
   components that have identifiers from other standard MIB modules
   associated with them.  For example, this table can be used along with
   the physical mapping table to identify the physical location of each
   repeater port in the rptrPortTable or each interface in the ifTable.

2.8.  Relationship to Naming Scopes

   There is some question as to which MIB objects may be returned within
   a given naming scope.  MIB objects that are not multi-scoped within a
   managed system are likely to ignore context information in

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   implementation.  In such a case, it is likely such objects will be
   returned in all naming scopes (e.g., not just the 'default' naming
   scope or the SNMPv3 default context).

   For example, a community string used to access the management
   information for logical device 'bridge2' may allow access to all the
   non-bridge-related objects in the 'default' naming scope, as well as
   a second instance of the Bridge MIB [RFC4188].

   The isolation of single-scoped MIB objects by the agent is an
   implementation-specific matter.  An agent may wish to limit the
   objects returned in a particular naming scope to only the multi-
   scoped objects in that naming scope (e.g., system group and the
   Bridge MIB).  In this case, all single-scoped management information
   would belong to a common naming scope (e.g., 'default'), which itself
   may contain some multi-scoped objects (e.g., system group).

2.9.  Multiple Instances of the Entity MIB

   It is possible that more than one agent may exist in a managed
   system.  In such cases, multiple instances of the Entity MIB
   (representing the same managed objects) may be available to an NMS.

   In order to reduce complexity for agent implementation, multiple
   instances of the Entity MIB are not required to be equivalent or even
   consistent.  An NMS may be able to 'align' instances returned by
   different agents by examining the columns of each table, but vendor-
   specific identifiers and (especially) index values are likely to be
   different.  Each agent may be managing different subsets of the
   entire chassis as well.

   When all of a physically modular device is represented by a single
   agent, the entry (for which entPhysicalContainedIn has the value
   zero) would likely have 'chassis' as the value of its
   entPhysicalClass.  Alternatively, for an agent on a module where the
   agent represents only the physical entities on that module (not those
   on other modules), the entry (for which entPhysicalContainedIn has
   the value zero) would likely have 'module' as the value of its
   entPhysicalClass.

   An agent implementation of the entLogicalTable is not required to
   contain information about logical entities managed primarily by other
   agents.  That is, the entLogicalTAddress and entLogicalTDomain
   objects in the entLogicalTable are provided to support a historical
   multiplexing mechanism, not to identify other SNMP agents.

   Note that the Entity MIB is a single-scoped MIB, in the event an
   agent represents the MIB in different naming scopes.

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2.10.  Re-Configuration of Entities

   Most of the MIB objects defined in this MIB have, at most, a read-
   only MAX-ACCESS clause.  This is a conscious decision by the working
   group to limit this MIB's scope.  The second version of the Entity
   MIB allows a network administrator to configure some common
   attributes of physical components.

2.11.  Textual Convention Change

   Version 1 of the Entity MIB contains three MIB objects defined with
   the (now obsolete) DisplayString TEXTUAL-CONVENTION.  In version 2 of
   the Entity MIB, the syntax for these objects has been updated to use
   the (now preferred) SnmpAdminString TEXTUAL-CONVENTION.

   The ENTMIB working group (which was in charge of the document at that
   point) realized that this change is not strictly supported by SMIv2.
   In their judgment, the alternative of deprecating the old objects and
   defining new objects would have had a more adverse impact on backward
   compatibility and interoperability, given the particular semantics of
   these objects.

2.12.  MIB Structure

   The Entity MIB contains five groups of MIB objects:

   - entityPhysical group
     Describes the physical entities managed by a single agent.

   - entityLogical group
     Describes the logical entities managed by a single agent.

   - entityMapping group
     Describes the associations between the physical entities, logical
     entities, interfaces, and non-interface ports managed by a single
     agent.

   - entityGeneral group
     Describes general system attributes shared by potentially all types
     of entities managed by a single agent.

   - entityNotifications group
     Contains status indication notifications.

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2.12.1.  entityPhysical Group

   This group contains a single table to identify physical system
   components, called the entPhysicalTable.

   The entPhysicalTable contains one row per physical entity and must
   always contain at least one row for an "overall" physical entity,
   which should have an entPhysicalClass value of 'stack(11)',
   'chassis(3)', or 'module(9)'.

   Each row is indexed by an arbitrary, small integer and contains a
   description and type of the physical entity.  It also optionally
   contains the index number of another entPhysicalEntry, indicating a
   containment relationship between the two.

   Version 2 of the Entity MIB provides additional MIB objects for each
   physical entity.  Some common read-only attributes have been added,
   as well as three writable string objects.

   - entPhysicalAlias
     This string can be used by an NMS as a non-volatile identifier for
     the physical component.  Maintaining a non-volatile string for
     every physical component represented in the entPhysicalTable can be
     costly and unnecessary.  An agent may algorithmically generate
     entPhysicalAlias strings for particular entries (e.g., based on the
     entPhysicalClass value).

   - entPhysicalAssetID
     This string is provided to store a user-specific asset identifier
     for removable physical components.  In order to reduce the non-
     volatile storage needed by a particular agent, a network
     administrator should only assign asset identifiers to physical
     entities that are field-replaceable (i.e., not permanently
     contained within another physical entity).

   - entPhysicalSerialNum
     This string is provided to store a vendor-specific serial number
     string for physical components.  This writable object is used when
     an agent cannot identify the serial numbers of all installed
     physical entities and a network administrator wishes to configure
     the non-volatile serial number strings manually (via an NMS
     application).

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   Version 3 of the Entity MIB provides two additional MIB objects for
   each physical entity:

   - entPhysicalMfgDate
     This object contains the date of manufacturing of the managed
     entity.  If the manufacturing date is unknown or not supported the
     object is not instantiated.  The special value '0000000000000000'H
     may also be returned in this case.

   - entPhysicalUris
     This object provides additional identification information about
     the physical entity.

     This object contains one or more Uniform Resource Identifiers
     (URIs); therefore, the syntax of this object must conform to
     [RFC3986], Section 3.  Uniform Resource Names (URNs) [RFC3406] are
     resource identifiers with the specific requirements for enabling
     location-independent identification of a resource, as well as
     longevity of reference.  URNs are part of the larger URI family
     with the specific goal of providing persistent naming of resources.
     URI schemes and URN namespaces are registered by IANA (see
     http://www.iana.org/assignments/uri-schemes and
     http://www.iana.org/assignments/urn-namespaces).

     For example, the entPhysicalUris object may be used to encode a URI
     containing a Common Language Equipment Identifier (CLEI) URN for
     the managed physical entity.  The URN namespace for CLEIs is
     defined in [RFC4152], and the CLEI format is defined in [T1.213]
     and [T1.213a].  For example, an entPhysicalUris instance may have
     the value of:

        URN:CLEI:D4CE18B7AA

     [RFC3986] and [RFC4152] identify this as a URI in the CLEI URN
     namespace.  The specific CLEI code, D4CE18B7AA, is based on the
     example provided in [T1.213a].

     Multiple URIs may be present and are separated by white space
     characters.  Leading and trailing white space characters are
     ignored.

     If no additional identification information is known about the
     physical entity or supported, the object is not instantiated.

     Version 4 of the Entity MIB module provides an additional MIB
     object for each physical entity.

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   - entPhysicalUUID
     This object provides an unique identification about the physical
     entity.  This object contains a globally unique identifier for the
     physical entity with the format defined in RFC 4122 [RFC4122].

     To support the existing implementations of ENTITY-MIB version 3
     [RFC4133], entPhysicalUris object should be used to store the UUID
     value of the physical entity as well in URN format.  This
     duplication of information enables backward compatibility.  Note
     that entPhysicalUris allows write access while entPhysicalUUID is
     read-only.

2.12.2.  entityLogical Group

   This group contains a single table to identify logical entities,
   called the entLogicalTable.

   The entLogicalTable contains one row per logical entity.  Each row is
   indexed by an arbitrary, small integer and contains a name,
   description, and type of the logical entity.  It also contains
   information to allow access to the MIB information for the logical
   entity.  This includes SNMP versions that use a community name (with
   some form of implied context representation) and SNMP versions that
   use the SNMP ARCH [RFC3411] method of context identification.

   If an agent represents multiple logical entities with this MIB, then
   this group must be implemented for all logical entities known to the
   agent.

   If an agent represents a single logical entity, or multiple logical
   entities within a single naming scope, then implementation of this
   group may be omitted by the agent.

2.12.3.  entityMapping Group

   This group contains three tables to identify associations between
   different system components.

   - entLPMappingTable
     This table contains mappings between entLogicalIndex values
     (logical entities) and entPhysicalIndex values (the physical
     components supporting that entity).  A logical entity can map to
     more than one physical component, and more than one logical entity
     can map to (share) the same physical component.  If an agent
     represents a single logical entity, or multiple logical entities
     within a single naming scope, then implementation of this table may
     be omitted by the agent.

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   - entAliasMappingTable
     This table contains mappings between entLogicalIndex,
     entPhysicalIndex pairs, and 'alias' object identifier values.  This
     allows resources managed with other MIB modules (e.g., repeater
     ports, bridge ports, physical and logical interfaces) to be
     identified in the physical entity hierarchy.  Note that each alias
     identifier is only relevant in a particular naming scope.  If an
     agent represents a single logical entity, or multiple logical
     entities within a single naming scope, then implementation of this
     table may be omitted by the agent.

   - entPhysicalContainsTable
     This table contains simple mappings between entPhysicalContainedIn
     values for each container/'containee' relationship in the managed
     system.  The indexing of this table allows an NMS to quickly
     discover the entPhysicalIndex values for all children of a given
     physical entity.

2.12.4.  entityGeneral Group

   This group contains general information relating to the other object
   groups.

   At this time, the entGeneral group contains a single scalar object
   (entLastChangeTime), which represents the value of sysUpTime when any
   part of the Entity MIB configuration last changed.

2.12.5.  entityNotifications Group

   This group contains notification definitions relating to the overall
   status of the Entity MIB instantiation.

2.13.  Multiple Agents

   Even though a primary motivation for this MIB is to represent the
   multiple logical entities supported by a single agent, another
   motivation is to represent multiple logical entities supported by
   multiple agents (in the same "overall" physical entity).  Indeed, it
   is implicit in the SNMP architecture that the number of agents is
   transparent to a network management station.

   However, there is no agreement at this time as to the degree of
   cooperation that should be expected for agent implementations.
   Therefore, multiple agents within the same managed system are free to
   implement the Entity MIB independently.  (For more information, refer
   to Section 2.9, "Multiple Instances of the Entity MIB".)

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2.14.  Changes Since RFC 2037

2.14.1.  Textual Conventions

   The PhysicalClass TC text has been clarified, and a new enumeration
   to support 'stackable' components has been added.  The
   SnmpEngineIdOrNone TC has been added to support SNMPv3.

2.14.2.  New entPhysicalTable Objects

   The entPhysicalHardwareRev, entPhysicalFirmwareRev, and
   entPhysicalSoftwareRev objects have been added for revision
   identification.

   The entPhysicalSerialNum, entPhysicalMfgName, entPhysicalModelName,
   and entPhysicalIsFRU objects have been added for better vendor
   identification for physical components.  In the event the agent
   cannot identify this information, the entPhysicalSerialNum object can
   be set by a management station.

   The entPhysicalAlias and entPhysicalAssetID objects have been added
   for better user component identification.  These objects are intended
   to be set by a management station and preserved by the agent across
   restarts.

2.14.3.  New entLogicalTable Objects

   The entLogicalContextEngineID and entLogicalContextName objects have
   been added to provide an SNMP context for SNMPv3 access on behalf of
   a logical entity.

2.14.4.  Bug Fixes

   A bug was fixed in the entLogicalCommunity object.  The subrange was
   incorrect (1..255) and is now correct (0..255).  The description
   clause has also been clarified.  This object is now deprecated.

   The entLastChangeTime object description has been changed to
   generalize the events that cause an update to the last change
   timestamp.

   The syntax was changed from DisplayString to SnmpAdminString for the
   entPhysicalDescr, entPhysicalName, and entLogicalDescr objects.

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2.15.  Changes Since RFC 2737

2.15.1.  Textual Conventions

   The PhysicalIndexOrZero TC has been added to allow objects to
   reference an entPhysicalIndex value or zero.  The PhysicalClass TC
   has been extended to support a new enumeration for central processing
   units.

2.15.2.  New Objects

   The entPhysicalMfgDate object has been added to the entPhysicalTable
   to provide the date of manufacturing of the managed entity.

   The entPhysicalUris object has been added to the entPhysicalTable to
   provide additional identification information about the physical
   entity, such as a Common Language Equipment Identifier (CLEI) URN.

2.15.3.  Bug Fixes

   The syntax was changed from INTEGER to Integer32 for the
   entPhysicalParentRelPos, entLogicalIndex, and
   entAliasLogicalIndexOrZero objects, and from INTEGER to
   PhysicalIndexOrZero for the entPhysicalContainedIn object.

2.16.  Changes Since RFC 4133

2.16.1.  MIB Module Addition

   Over time, there may be the need to add new enumerated values to the
   PhysicalClass TEXTUAL-CONVENTION.  To allow for such additions
   without requiring re-issuing of this MIB module, a new MIB module
   called IANA-ENTITY-MIB that provides the IANA-maintained TEXTUAL-
   CONVENTION IANAPhysicalClass has been created.  The PhysicalClass TC
   has been deprecated.

2.16.2.  Modification to Some of the MIB Objects

   A new MIB object has been added to the entPhysicalTable,
   entPhysicalUUID.  In comparison to entPhysicalUris, the new object is
   read-only and restricted to a fixed size to allow only for RFC 4122
   [RFC4122] compliant values.  The PhysicalClass TEXTUAL-CONVENTION was
   deprecated, and a new IANAPhysicalClass TC (maintained by IANA) has
   been created.

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   Two new MODULE-COMPLIANCE modules have been created:
   entity4Compliance for full compliance with version 4 of the Entity
   MIB, and entity4CRCompliance for devices with constrained resources
   like batteries that might require a limited number of objects to be
   supported (entPhysicalClass, entPhysicalName, and entPhysicalUUID).

2.16.3.  New TC for Universally Unique Identifier

   A new TEXTUAL-CONVENTION, UUIDorZero, was created to represent a
   Universally Unique Identifier (UUID) with a syntax that conforms to
   [RFC4122], Section 4.1.  Defining it as a TC will allow for future
   reuse in other MIB modules that will import the TC.  This Textual
   Convention is included in the UUID-TC-MIB module.

3.  MIB Definitions

3.1. ENTITY-MIB

ENTITY-MIB DEFINITIONS ::= BEGIN

IMPORTS
    MODULE-IDENTITY, OBJECT-TYPE, mib-2, NOTIFICATION-TYPE,
    Integer32
        FROM SNMPv2-SMI                       -- RFC 2578
    TDomain, TAddress, TEXTUAL-CONVENTION,
    AutonomousType, RowPointer, TimeStamp, TruthValue,
    DateAndTime
        FROM SNMPv2-TC                        -- RFC 2579
    MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
        FROM SNMPv2-CONF                      -- RFC 2580
    SnmpAdminString
        FROM SNMP-FRAMEWORK-MIB               -- RFC 3411
    UUIDorZero
        FROM UUID-TC-MIB                      -- RFC 6933
    IANAPhysicalClass
        FROM IANA-ENTITY-MIB;                 -- RFC 6933

entityMIB MODULE-IDENTITY
    LAST-UPDATED "201304050000Z"      -- April 5, 2013
    ORGANIZATION "IETF Energy Management Working Group"
    CONTACT-INFO
            "WG Email: [email protected]
            Mailing list subscription info:
            http://www.ietf.org/mailman/listinfo/eman

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RFC 6933                 Entity MIB (Version 4)                 May 2013

            Andy Bierman
            YumaWorks, Inc.
            274 Redwood Shores Parkway, #133
            Redwood City, CA 94065
            USA
            Phone: +1 408-716-0466
            Email: [email protected]

            Dan Romascanu
            Avaya
            Park Atidim, Bldg. #3
            Tel Aviv, 61581
            Israel
            Phone: +972-3-6458414
            Email: [email protected]

            Juergen Quittek
            NEC Europe Ltd.
            Network Research Division
            Kurfuersten-Anlage 36
            Heidelberg  69115
            Germany
            Phone: +49 6221 4342-115
            Email: [email protected]

            Mouli Chandramouli
            Cisco Systems, Inc.
            Sarjapur Outer Ring Road
            Bangalore 560103
            India
            Phone: +91 80 4429 2409
            Email: [email protected]"

    DESCRIPTION
            "The MIB module for representing multiple logical
            entities supported by a single SNMP agent.

            Copyright (c) 2013 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)."

    REVISION        "201304050000Z"      -- April 5, 2013

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    DESCRIPTION
            "Entity MIB (Version 4).
            This revision obsoletes RFC 4133.
            - Creation of a new MIB module, IANA-ENTITY-MIB, which
            makes the PhysicalIndex TC an IANA-maintained TEXTUAL-
            CONVENTION.  IANAPhysicalClass is now imported
            from the IANA-ENTITY-MIB.
            - Addition of a new MIB object to the entPhysicalTable,
            entPhysicalUUID.  UUIDorZero is imported from the
            UUID-TC-MIB.
            - Addition of two new MODULE-COMPLIANCE modules-
            entity4Compliance and entity4CRCompliance.
            This version is published as RFC 6933."

    REVISION        "200508100000Z"
    DESCRIPTION
            "Initial Version of Entity MIB (Version 3).
             This revision obsoletes RFC 2737.
             Additions:
               - cpu(12) enumeration added to IANAPhysicalClass TC
               - DISPLAY-HINT clause to PhysicalIndex TC
               - PhysicalIndexOrZero TC
               - entPhysicalMfgDate object
               - entPhysicalUris object
             Changes:
               - entPhysicalContainedIn SYNTAX changed from
                 INTEGER to PhysicalIndexOrZero

             This version was published as RFC 4133."

    REVISION        "199912070000Z"
    DESCRIPTION
            "Initial Version of Entity MIB (Version 2).
             This revision obsoletes RFC 2037.
             This version was published as RFC 2737."

    REVISION        "199610310000Z"
    DESCRIPTION
            "Initial version (version 1), published as
             RFC 2037."
    ::= { mib-2 47 }

entityMIBObjects OBJECT IDENTIFIER ::= { entityMIB 1 }

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-- MIB contains four groups
entityPhysical OBJECT IDENTIFIER ::= { entityMIBObjects 1 }
entityLogical  OBJECT IDENTIFIER ::= { entityMIBObjects 2 }
entityMapping  OBJECT IDENTIFIER ::= { entityMIBObjects 3 }
entityGeneral  OBJECT IDENTIFIER ::= { entityMIBObjects 4 }

-- Textual Conventions
PhysicalIndex ::= TEXTUAL-CONVENTION
    DISPLAY-HINT      "d"
    STATUS            current
    DESCRIPTION
            "An arbitrary value that uniquely identifies the physical
            entity.  The value should be a small positive integer.
            Index values for different physical entities are not
            necessarily contiguous."
    SYNTAX Integer32 (1..2147483647)

PhysicalIndexOrZero ::= TEXTUAL-CONVENTION
    DISPLAY-HINT      "d"
    STATUS            current
    DESCRIPTION
            "This TEXTUAL-CONVENTION is an extension of the
            PhysicalIndex convention, which defines a greater than zero
            value used to identify a physical entity.  This extension
            permits the additional value of zero.  The semantics of the
            value zero are object-specific and must, therefore, be
            defined as part of the description of any object that uses
            this syntax.  Examples of the usage of this extension are
            situations where none or all physical entities need to be
            referenced."
    SYNTAX Integer32 (0..2147483647)

SnmpEngineIdOrNone ::= TEXTUAL-CONVENTION
    STATUS            current
    DESCRIPTION
            "A specially formatted SnmpEngineID string for use with the
            Entity MIB.

            If an instance of an object of SYNTAX SnmpEngineIdOrNone has
            a non-zero length, then the object encoding and semantics
            are defined by the SnmpEngineID TEXTUAL-CONVENTION (see STD
            62, RFC 3411).

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            If an instance of an object of SYNTAX SnmpEngineIdOrNone
            contains a zero-length string, then no appropriate
            SnmpEngineID is associated with the logical entity (i.e.,
            SNMPv3 is not supported)."
    SYNTAX OCTET STRING (SIZE(0..32)) -- empty string or SnmpEngineID

PhysicalClass ::= TEXTUAL-CONVENTION
    STATUS            deprecated
    DESCRIPTION
            "Starting with version 4 of the ENTITY-MIB, this TC is
            deprecated, and the usage of the IANAPhysicalClass TC from
            the IANA-ENTITY-MIB is recommended instead.

            An enumerated value that provides an indication of the
            general hardware type of a particular physical entity.
            There are no restrictions as to the number of
            entPhysicalEntries of each entPhysicalClass, which must be
            instantiated by an agent.

            The enumeration 'other' is applicable if the physical entity
            class is known but does not match any of the supported
            values.

            The enumeration 'unknown' is applicable if the physical
            entity class is unknown to the agent.

            The enumeration 'chassis' is applicable if the physical
            entity class is an overall container for networking
            equipment.  Any class of physical entity, except a stack,
            may be contained within a chassis; a chassis may only
            be contained within a stack.

            The enumeration 'backplane' is applicable if the physical
            entity 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 agent may model a
            backplane as a single physical entity, which is actually
            implemented as multiple discrete physical components (within
            a chassis or stack).

            The enumeration 'container' is applicable if the physical
            entity 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
            entities should be modeled within a container entity, such

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RFC 6933                 Entity MIB (Version 4)                 May 2013

            as field-replaceable modules, fans, or power supplies.  Note
            that all known containers should be modeled by the agent,
            including empty containers.

            The enumeration 'powerSupply' is applicable if the physical
            entity class is a power-supplying component.

            The enumeration 'fan' is applicable if the physical entity
            class is a fan or other heat-reduction component.

            The enumeration 'sensor' is applicable if the physical
            entity class is some sort of sensor, such as a temperature
            sensor within a router chassis.

            The enumeration 'module' is applicable if the physical
            entity class is some sort of self-contained sub-system.  If
            the enumeration 'module' is removable, then it should be
            modeled within a container entity; otherwise, it should be
            modeled directly within another physical entity (e.g., a
            chassis or another module).

            The enumeration 'port' is applicable if the physical entity
            class is some sort of networking port capable of receiving
            and/or transmitting networking traffic.

            The enumeration 'stack' is applicable if the physical entity
            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 may in
            fact be comprised of multiple interconnect cables.  A stack
            should not be modeled within any other physical entities,
            but a stack may be contained within another stack.  Only
            chassis entities should be contained within a stack.

            The enumeration 'cpu' is applicable if the physical entity
            class is some sort of central processing unit."
    SYNTAX      INTEGER  {
       other(1),
       unknown(2),
       chassis(3),
       backplane(4),
       container(5),     -- e.g., chassis slot or daughter-card holder
       powerSupply(6),
       fan(7),
       sensor(8),
       module(9),        -- e.g., plug-in card or daughter-card
       port(10),

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       stack(11),        -- e.g., stack of multiple chassis entities
       cpu(12)
    }

--           The Physical Entity Table
entPhysicalTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF EntPhysicalEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "This table contains one row per physical entity.  There is
            always at least one row for an 'overall' physical entity."
    ::= { entityPhysical 1 }

entPhysicalEntry       OBJECT-TYPE
    SYNTAX      EntPhysicalEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "Information about a particular physical entity.

            Each entry provides objects (entPhysicalDescr,
            entPhysicalVendorType, and entPhysicalClass) to help an NMS
            identify and characterize the entry and objects
            (entPhysicalContainedIn and entPhysicalParentRelPos) to help
            an NMS relate the particular entry to other entries in this
            table."
    INDEX   { entPhysicalIndex }
    ::= { entPhysicalTable 1 }

EntPhysicalEntry ::= SEQUENCE {
      entPhysicalIndex          PhysicalIndex,
      entPhysicalDescr          SnmpAdminString,
      entPhysicalVendorType     AutonomousType,
      entPhysicalContainedIn    PhysicalIndexOrZero,
      entPhysicalClass          IANAPhysicalClass,
      entPhysicalParentRelPos   Integer32,
      entPhysicalName           SnmpAdminString,
      entPhysicalHardwareRev    SnmpAdminString,
      entPhysicalFirmwareRev    SnmpAdminString,
      entPhysicalSoftwareRev    SnmpAdminString,
      entPhysicalSerialNum      SnmpAdminString,
      entPhysicalMfgName        SnmpAdminString,
      entPhysicalModelName      SnmpAdminString,
      entPhysicalAlias          SnmpAdminString,
      entPhysicalAssetID        SnmpAdminString,
      entPhysicalIsFRU          TruthValue,

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      entPhysicalMfgDate        DateAndTime,
      entPhysicalUris           OCTET STRING,
      entPhysicalUUID           UUIDorZero

}

entPhysicalIndex    OBJECT-TYPE
    SYNTAX      PhysicalIndex
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "The index for this entry."
    ::= { entPhysicalEntry 1 }

entPhysicalDescr OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "A textual description of physical entity.  This object
            should contain a string that identifies the manufacturer's
            name for the physical entity and should be set to a
            distinct value for each version or model of the physical
            entity."
    ::= { entPhysicalEntry 2 }

entPhysicalVendorType OBJECT-TYPE
    SYNTAX      AutonomousType
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "An indication of the vendor-specific hardware type of the
            physical entity.  Note that this is different from the
            definition of MIB-II's sysObjectID.

            An agent should set this object to an enterprise-specific
            registration identifier value indicating the specific
            equipment type in detail.  The associated instance of
            entPhysicalClass is used to indicate the general type of
            hardware device.

            If no vendor-specific registration identifier exists for
            this physical entity, or the value is unknown by this agent,
            then the value { 0 0 } is returned."
    ::= { entPhysicalEntry 3 }

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entPhysicalContainedIn OBJECT-TYPE
    SYNTAX      PhysicalIndexOrZero
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The value of entPhysicalIndex for the physical entity that
            'contains' this physical entity.  A value of zero indicates
            this physical entity is not contained in any other physical
            entity.  Note that the set of 'containment' relationships
            define a strict hierarchy; that is, recursion is not
            allowed.

            In the event that a physical entity is contained by more
            than one physical entity (e.g., double-wide modules), this
            object should identify the containing entity with the lowest
            value of entPhysicalIndex."
    ::= { entPhysicalEntry 4 }

entPhysicalClass OBJECT-TYPE
    SYNTAX      IANAPhysicalClass
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "An indication of the general hardware type of the physical
            entity.

            An agent should set this object to the standard enumeration
            value that most accurately indicates the general class of
            the physical entity, or the primary class if there is more
            than one entity.

            If no appropriate standard registration identifier exists
            for this physical entity, then the value 'other(1)' is
            returned.  If the value is unknown by this agent, then the
            value 'unknown(2)' is returned."
    ::= { entPhysicalEntry 5 }

entPhysicalParentRelPos OBJECT-TYPE
    SYNTAX      Integer32 (-1..2147483647)
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "An indication of the relative position of this 'child'
            component among all its 'sibling' components.  Sibling
            components are defined as entPhysicalEntries that share the
            same instance values of each of the entPhysicalContainedIn
            and entPhysicalClass objects.

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            An NMS can use this object to identify the relative ordering
            for all sibling components of a particular parent
            (identified by the entPhysicalContainedIn instance in each
            sibling entry).

            If possible, this value should match any external labeling
            of the physical component.  For example, for a container
            (e.g., card slot) labeled as 'slot #3',
            entPhysicalParentRelPos should have the value '3'.  Note
            that the entPhysicalEntry for the module plugged in slot 3
            should have an entPhysicalParentRelPos value of '1'.

            If the physical position of this component does not match
            any external numbering or clearly visible ordering, then
            user documentation or other external reference material
            should be used to determine the parent-relative position.
            If this is not possible, then the agent should assign a
            consistent (but possibly arbitrary) ordering to a given set
            of 'sibling' components, perhaps based on internal
            representation of the components.

            If the agent cannot determine the parent-relative position
            for some reason, or if the associated value of
            entPhysicalContainedIn is '0', then the value '-1' is
            returned.  Otherwise, a non-negative integer is returned,
            indicating the parent-relative position of this physical
            entity.

            Parent-relative ordering normally starts from '1' and
            continues to 'N', where 'N' represents the highest
            positioned child entity.  However, if the physical entities
            (e.g., slots) are labeled from a starting position of zero,
            then the first sibling should be associated with an
            entPhysicalParentRelPos value of '0'.  Note that this
            ordering may be sparse or dense, depending on agent
            implementation.

            The actual values returned are not globally meaningful, as
            each 'parent' component may use different numbering
            algorithms.  The ordering is only meaningful among siblings
            of the same parent component.

            The agent should retain parent-relative position values
            across reboots, either through algorithmic assignment or use
            of non-volatile storage."
    ::= { entPhysicalEntry 6 }

entPhysicalName OBJECT-TYPE

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    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The textual name of the physical entity.  The value of this
            object should be the name of the component as assigned by
            the local device and should be suitable for use in commands
            entered at the device's 'console'.  This might be a text
            name (e.g., 'console') or a simple component number (e.g.,
            port or module number, such as '1'), depending on the
            physical component naming syntax of the device.

            If there is no local name, or if this object is otherwise
            not applicable, then this object contains a zero-length
            string.

            Note that the value of entPhysicalName for two physical
            entities will be the same in the event that the console
            interface does not distinguish between them, e.g., slot-1
            and the card in slot-1."
    ::= { entPhysicalEntry 7 }

entPhysicalHardwareRev    OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The vendor-specific hardware revision string for the
            physical entity.  The preferred value is the hardware
            revision identifier actually printed on the component itself
            (if present).

            Note that if revision information is stored internally in a
            non-printable (e.g., binary) format, then the agent must
            convert such information to a printable format in an
            implementation-specific manner.

            If no specific hardware revision string is associated with
            the physical component, or if this information is unknown to
            the agent, then this object will contain a zero-length
            string."
    ::= { entPhysicalEntry 8 }

entPhysicalFirmwareRev    OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current

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    DESCRIPTION
            "The vendor-specific firmware revision string for the
            physical entity.

            Note that if revision information is stored internally in a
            non-printable (e.g., binary) format, then the agent must
            convert such information to a printable format in an
            implementation-specific manner.

            If no specific firmware programs are associated with the
            physical component, or if this information is unknown to the
            agent, then this object will contain a zero-length string."
    ::= { entPhysicalEntry 9 }

entPhysicalSoftwareRev    OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The vendor-specific software revision string for the
            physical entity.

            Note that if revision information is stored internally in a
            non-printable (e.g., binary) format, then the agent must
            convert such information to a printable format in an
            implementation-specific manner.

            If no specific software programs are associated with the
            physical component, or if this information is unknown to the
            agent, then this object will contain a zero-length string."
    ::= { entPhysicalEntry 10 }

entPhysicalSerialNum   OBJECT-TYPE
    SYNTAX      SnmpAdminString (SIZE (0..32))
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
            "The vendor-specific serial number string for the physical
            entity.  The preferred value is the serial number string
            actually printed on the component itself (if present).

            On the first instantiation of a physical entity, the value
            of entPhysicalSerialNum associated with that entity is set
            to the correct vendor-assigned serial number, if this
            information is available to the agent.  If a serial number
            is unknown or non-existent, the entPhysicalSerialNum will be
            set to a zero-length string instead.

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            Note that implementations that can correctly identify the
            serial numbers of all installed physical entities do not
            need to provide write access to the entPhysicalSerialNum
            object.  Agents that cannot provide non-volatile storage
            for the entPhysicalSerialNum strings are not required to
            implement write access for this object.

            Not every physical component will have a serial number, or
            even need one.  Physical entities for which the associated
            value of the entPhysicalIsFRU object is equal to 'false(2)'
            (e.g., the repeater ports within a repeater module) do not
            need their own unique serial numbers.  An agent does not
            have to provide write access for such entities and may
            return a zero-length string.

            If write access is implemented for an instance of
            entPhysicalSerialNum and a value is written into the
            instance, the agent must retain the supplied value in the
            entPhysicalSerialNum instance (associated with the same
            physical entity) for as long as that entity remains
            instantiated.  This includes instantiations across all
            re-initializations/reboots of the network management system,
            including those resulting in a change of the physical
            entity's entPhysicalIndex value."
    ::= { entPhysicalEntry 11 }

entPhysicalMfgName   OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    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
            entPhysicalModelName, entPhysicalFirmwareRev,
            entPhysicalSoftwareRev, and the entPhysicalSerialNum
            objects are only meaningful amongst entPhysicalEntries with
            the same value of entPhysicalMfgName.

            If the manufacturer name string associated with the physical
            component is unknown to the agent, then this object will
            contain a zero-length string."
    ::= { entPhysicalEntry 12 }

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entPhysicalModelName   OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    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 agent, then this object will
            contain a zero-length string."
    ::= { entPhysicalEntry 13 }

entPhysicalAlias    OBJECT-TYPE
    SYNTAX      SnmpAdminString (SIZE (0..32))
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
            "This object is an 'alias' name for the physical entity, as
            specified by a network manager, and provides a non-volatile
            'handle' for the physical entity.

            On the first instantiation of a physical entity, the value
            of entPhysicalAlias associated with that entity is set to
            the zero-length string.  However, the agent may set the
            value to a locally unique default value, instead of a
            zero-length string.

            If write access is implemented for an instance of
            entPhysicalAlias and a value is written into the instance,
            the agent must retain the supplied value in the
            entPhysicalAlias instance (associated with the same physical
            entity) for as long as that entity remains instantiated.
            This includes instantiations across all
            re-initializations/reboots of the network management system,
            including those resulting in a change of the physical
            entity's entPhysicalIndex value."
    ::= { entPhysicalEntry 14 }

entPhysicalAssetID OBJECT-TYPE
    SYNTAX      SnmpAdminString (SIZE (0..32))
    MAX-ACCESS  read-write
    STATUS      current

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    DESCRIPTION
            "This object is a user-assigned asset tracking identifier
            (as specified by a network manager) for the physical entity
            and provides non-volatile storage of this information.

            On the first instantiation of a physical entity, the value
            of entPhysicalAssetID associated with that entity is set to
            the zero-length string.

            Not every physical component will have an asset tracking
            identifier or even need one.  Physical entities for which
            the associated value of the entPhysicalIsFRU object is equal
            to 'false(2)' (e.g., the repeater ports within a repeater
            module) do not need their own unique asset tracking
            identifier.  An agent does not have to provide write access
            for such entities and may instead return a zero-length
            string.

            If write access is implemented for an instance of
            entPhysicalAssetID and a value is written into the
            instance, the agent must retain the supplied value in the
            entPhysicalAssetID instance (associated with the same
            physical entity) for as long as that entity remains
            instantiated.  This includes instantiations across all
            re-initializations/reboots of the network management system,
            including those resulting in a change of the physical
            entity's entPhysicalIndex value.

            If no asset tracking information is associated with the
            physical component, then this object will contain a
            zero-length string."
    ::= { entPhysicalEntry 15 }

entPhysicalIsFRU OBJECT-TYPE
    SYNTAX      TruthValue
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "This object indicates whether or not this physical entity
            is considered a 'field replaceable unit' by the vendor.
            If this object contains the value 'true(1)', then this
            entPhysicalEntry identifies a field replaceable unit.  For
            all entPhysicalEntries that represent components
            permanently contained within a field replaceable unit, the
            value 'false(2)' should be returned for this object."
    ::= { entPhysicalEntry 16 }

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entPhysicalMfgDate  OBJECT-TYPE
    SYNTAX      DateAndTime
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "This object contains the date of manufacturing of the
            managed entity.  If the manufacturing date is unknown or
            not supported, the object is not instantiated.  The special
            value '0000000000000000'H may also be returned in this
            case."
    ::= { entPhysicalEntry 17 }

entPhysicalUris OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
            "This object contains identification
            information about the physical entity.  The object
            contains URIs; therefore, the syntax of this object
            must conform to RFC 3986, Section 3.

            Multiple URIs may be present and are separated by white
            space characters.  Leading and trailing white space
            characters are ignored.

            If no URI identification information is known
            about the physical entity, the object is not
            instantiated.  A zero-length octet string may also be
            returned in this case."
    REFERENCE
            "RFC 3986, Uniform Resource Identifiers (URI): Generic
            Syntax, Section 2, August 1998."

    ::= { entPhysicalEntry 18 }

entPhysicalUUID OBJECT-TYPE
    SYNTAX      UUIDorZero
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "This object contains identification information
            about the physical entity.  The object contains a
            Universally Unique Identifier, the syntax of this object
            must conform to RFC 4122, Section 4.1.

            A zero-length octet string is returned if no UUID
            information is known."

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    REFERENCE
            "RFC 4122, A Universally Unique IDentifier (UUID) URN
            Namespace, Section 4.1, July 2005."

    ::= { entPhysicalEntry 19 }

--           The Logical Entity Table
entLogicalTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF EntLogicalEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "This table contains one row per logical entity.  For agents
            that implement more than one naming scope, at least one
            entry must exist.  Agents that instantiate all MIB objects
            within a single naming scope are not required to implement
            this table."
    ::= { entityLogical 1 }

entLogicalEntry       OBJECT-TYPE
    SYNTAX      EntLogicalEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "Information about a particular logical entity.  Entities
            may be managed by this agent or other SNMP agents (possibly)
            in the same chassis."
    INDEX       { entLogicalIndex }
    ::= { entLogicalTable 1 }

EntLogicalEntry ::= SEQUENCE {
      entLogicalIndex            Integer32,
      entLogicalDescr            SnmpAdminString,
      entLogicalType             AutonomousType,
      entLogicalCommunity        OCTET STRING,
      entLogicalTAddress         TAddress,
      entLogicalTDomain          TDomain,
      entLogicalContextEngineID  SnmpEngineIdOrNone,
      entLogicalContextName      SnmpAdminString
}

entLogicalIndex OBJECT-TYPE
    SYNTAX      Integer32 (1..2147483647)
    MAX-ACCESS  not-accessible
    STATUS      current

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    DESCRIPTION
            "The value of this object uniquely identifies the logical
            entity.  The value should be a small positive integer; index
            values for different logical entities are not necessarily
            contiguous."
    ::= { entLogicalEntry 1 }

entLogicalDescr OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "A textual description of the logical entity.  This object
            should contain a string that identifies the manufacturer's
            name for the logical entity and should be set to a distinct
            value for each version of the logical entity."
    ::= { entLogicalEntry 2 }

entLogicalType OBJECT-TYPE
    SYNTAX      AutonomousType
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "An indication of the type of logical entity.  This will
            typically be the OBJECT IDENTIFIER name of the node in the
            SMI's naming hierarchy that represents the major MIB
            module, or the majority of the MIB modules, supported by the
            logical entity.  For example:
               a logical entity of a regular host/router -> mib-2
               a logical entity of a 802.1d bridge -> dot1dBridge
               a logical entity of a 802.3 repeater -> snmpDot3RptrMgmt
            If an appropriate node in the SMI's naming hierarchy cannot
            be identified, the value 'mib-2' should be used."
    ::= { entLogicalEntry 3 }

entLogicalCommunity OBJECT-TYPE
    SYNTAX      OCTET STRING (SIZE (0..255))
    MAX-ACCESS  read-only
    STATUS      deprecated
    DESCRIPTION
            "An SNMPv1 or SNMPv2c community string, which can be used to
            access detailed management information for this logical
            entity.  The agent should allow read access with this
            community string (to an appropriate subset of all managed
            objects) and may also return a community string based on the
            privileges of the request used to read this object.  Note
            that an agent may return a community string with read-only
            privileges, even if this object is accessed with a

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            read-write community string.  However, the agent must take
            care not to return a community string that allows more
            privileges than the community string used to access this
            object.

            A compliant SNMP agent may wish to conserve naming scopes by
            representing multiple logical entities in a single 'default'
            naming scope.  This is possible when the logical entities,
            represented by the same value of entLogicalCommunity, have
            no object instances in common.  For example, 'bridge1' and
            'repeater1' may be part of the main naming scope, but at
            least one additional community string is needed to represent
            'bridge2' and 'repeater2'.

            Logical entities 'bridge1' and 'repeater1' would be
            represented by sysOREntries associated with the 'default'
            naming scope.

            For agents not accessible via SNMPv1 or SNMPv2c, the value
            of this object is the empty string.  This object may also
            contain an empty string if a community string has not yet
            been assigned by the agent or if no community string with
            suitable access rights can be returned for a particular SNMP
            request.

            Note that this object is deprecated.  Agents that implement
            SNMPv3 access should use the entLogicalContextEngineID and
            entLogicalContextName objects to identify the context
            associated with each logical entity.  SNMPv3 agents may
            return a zero-length string for this object or may continue
            to return a community string (e.g., tri-lingual agent
            support)."
    ::= { entLogicalEntry 4 }

entLogicalTAddress OBJECT-TYPE
    SYNTAX      TAddress
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The transport service address by which the logical entity
            receives network management traffic, formatted according to
            the corresponding value of entLogicalTDomain.

            For snmpUDPDomain, a TAddress is 6 octets long: the initial
            4 octets contain the IP-address in network-byte order, and
            the last 2 contain the UDP port in network-byte order.
            Consult RFC 3417 for further information on snmpUDPDomain."

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    REFERENCE
            "Transport Mappings for the Simple Network Management
            Protocol (SNMP), STD 62, RFC 3417."
    ::= { entLogicalEntry 5 }

entLogicalTDomain OBJECT-TYPE
    SYNTAX      TDomain
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "Indicates the kind of transport service by which the
            logical entity receives network management traffic.
            Possible values for this object are presently found in
            RFC 3417."
    REFERENCE
            "Transport Mappings for the Simple Network Management
            Protocol (SNMP), STD 62, RFC 3417."
    ::= { entLogicalEntry 6 }

entLogicalContextEngineID    OBJECT-TYPE
    SYNTAX      SnmpEngineIdOrNone
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The authoritative contextEngineID that can be used to send
            an SNMP message concerning information held by this logical
            entity to the address specified by the associated
            'entLogicalTAddress/entLogicalTDomain' pair.

            This object, together with the associated
            entLogicalContextName object, defines the context associated
            with a particular logical entity and allows access to SNMP
            engines identified by a contextEngineID and contextName
            pair.

            If no value has been configured by the agent, a zero-length
            string is returned, or the agent may choose not to
            instantiate this object at all."
    ::= { entLogicalEntry 7 }

entLogicalContextName    OBJECT-TYPE
    SYNTAX      SnmpAdminString
    MAX-ACCESS  read-only
    STATUS      current

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    DESCRIPTION
            "The contextName that can be used to send an SNMP message
            concerning information held by this logical entity to the
            address specified by the associated
            'entLogicalTAddress/entLogicalTDomain' pair.

            This object, together with the associated
            entLogicalContextEngineID object, defines the context
            associated with a particular logical entity and allows
            access to SNMP engines identified by a contextEngineID and
            contextName pair.

            If no value has been configured by the agent, a zero-length
            string is returned, or the agent may choose not to
            instantiate this object at all."
    ::= { entLogicalEntry 8 }

entLPMappingTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF EntLPMappingEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "This table contains zero or more rows of logical entity to
            physical equipment associations.  For each logical entity
            known by this agent, there are zero or more mappings to the
            physical resources, which are used to realize that logical
            entity.

            An agent should limit the number and nature of entries in
            this table such that only meaningful and non-redundant
            information is returned.  For example, in a system that
            contains a single power supply, mappings between logical
            entities and the power supply are not useful and should not
            be included.

            Also, only the most appropriate physical component, which is
            closest to the root of a particular containment tree, should
            be identified in an entLPMapping entry.

            For example, suppose a bridge is realized on a particular
            module, and all ports on that module are ports on this
            bridge.  A mapping between the bridge and the module would
            be useful, but additional mappings between the bridge and
            each of the ports on that module would be redundant (because
            the entPhysicalContainedIn hierarchy can provide the same
            information).  On the other hand, if more than one bridge
            were utilizing ports on this module, then mappings between
            each bridge and the ports it used would be appropriate.

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            Also, in the case of a single backplane repeater, a mapping
            for the backplane to the single repeater entity is not
            necessary."
    ::= { entityMapping 1 }

entLPMappingEntry       OBJECT-TYPE
    SYNTAX      EntLPMappingEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "Information about a particular logical-entity-to-physical-
            equipment association.  Note that the nature of the
            association is not specifically identified in this entry.
            It is expected that sufficient information exists in the
            MIB modules used to manage a particular logical entity to
            infer how physical component information is utilized."
    INDEX       { entLogicalIndex, entLPPhysicalIndex }
    ::= { entLPMappingTable 1 }

EntLPMappingEntry ::= SEQUENCE {
      entLPPhysicalIndex         PhysicalIndex
}

entLPPhysicalIndex OBJECT-TYPE
    SYNTAX      PhysicalIndex
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The value of this object identifies the index value of a
            particular entPhysicalEntry associated with the indicated
            entLogicalEntity."
    ::= { entLPMappingEntry 1 }

-- logical entity/component to alias table
entAliasMappingTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF EntAliasMappingEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "This table contains zero or more rows, representing
            mappings of logical entities and physical components to
            external MIB identifiers.  Each physical port in the system
            may be associated with a mapping to an external identifier,
            which itself is associated with a particular logical

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            entity's naming scope.  A 'wildcard' mechanism is provided
            to indicate that an identifier is associated with more than
            one logical entity."
    ::= { entityMapping 2 }

entAliasMappingEntry       OBJECT-TYPE
    SYNTAX      EntAliasMappingEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "Information about a particular binding between a
            logical entity/physical component pair and an external
            identifier.  Each logical entity/physical component pair
            may be associated with one alias mapping.
            The logical entity index may also be used as
            a 'wildcard' (refer to the entAliasLogicalIndexOrZero object
            DESCRIPTION clause for details.)

            Note that only entPhysicalIndex values that represent
            physical ports (i.e., associated entPhysicalClass value is
            'port(10)') are permitted to exist in this table."
    INDEX { entPhysicalIndex, entAliasLogicalIndexOrZero }
    ::= { entAliasMappingTable 1 }

EntAliasMappingEntry ::= SEQUENCE {
      entAliasLogicalIndexOrZero        Integer32,
      entAliasMappingIdentifier         RowPointer
}

entAliasLogicalIndexOrZero OBJECT-TYPE
    SYNTAX      Integer32 (0..2147483647)
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "The value of this object identifies the logical entity
            that defines the naming scope for the associated instance
            of the entAliasMappingIdentifier object.

            If this object has a non-zero value, then it identifies the
            logical entity named by the same value of entLogicalIndex.

            If this object has a value of zero, then the mapping between
            the physical component and the alias identifier for this
            entAliasMapping entry is associated with all unspecified
            logical entities.  That is, a value of zero (the default
            mapping) identifies any logical entity that does not have
            an explicit entry in this table for a particular
            entPhysicalIndex/entAliasMappingIdentifier pair.

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            For example, to indicate that a particular interface (e.g.,
            physical component 33) is identified by the same value of
            ifIndex for all logical entities, the following instance
            might exist:

                    entAliasMappingIdentifier.33.0 = ifIndex.5

            In the event an entPhysicalEntry is associated differently
            for some logical entities, additional entAliasMapping
            entries may exist, e.g.:

                    entAliasMappingIdentifier.33.0 = ifIndex.6
                    entAliasMappingIdentifier.33.4 =  ifIndex.1
                    entAliasMappingIdentifier.33.5 =  ifIndex.1
                    entAliasMappingIdentifier.33.10 = ifIndex.12

            Note that entries with non-zero entAliasLogicalIndexOrZero
            index values have precedence over zero-indexed entries.  In
            this example, all logical entities except 4, 5, and 10
            associate physical entity 33 with ifIndex.6."
    ::= { entAliasMappingEntry 1 }

entAliasMappingIdentifier OBJECT-TYPE
    SYNTAX      RowPointer
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The value of this object identifies a particular conceptual
            row associated with the indicated entPhysicalIndex and
            entLogicalIndex pair.

            Because only physical ports are modeled in this table, only
            entries that represent interfaces or ports are allowed.  If
            an ifEntry exists on behalf of a particular physical port,
            then this object should identify the associated ifEntry.
            For repeater ports, the appropriate row in the
            'rptrPortGroupTable' should be identified instead.

            For example, suppose a physical port was represented by
            entPhysicalEntry.3, entLogicalEntry.15 existed for a
            repeater, and entLogicalEntry.22 existed for a bridge.  Then
            there might be two related instances of
            entAliasMappingIdentifier:

               entAliasMappingIdentifier.3.15 == rptrPortGroupIndex.5.2
               entAliasMappingIdentifier.3.22 == ifIndex.17

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            It is possible that other mappings (besides interfaces and
            repeater ports) may be defined in the future, as required.

            Bridge ports are identified by examining the Bridge MIB and
            appropriate ifEntries associated with each 'dot1dBasePort'
            and are thus not represented in this table."
    ::= { entAliasMappingEntry 2 }

-- physical mapping table
entPhysicalContainsTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF EntPhysicalContainsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "A table that exposes the container/'containee'
            relationships between physical entities.  This table
            provides all the information found by constructing the
            virtual containment tree for a given entPhysicalTable, but
            in a more direct format.

            In the event a physical entity is contained by more than one
            other physical entity (e.g., double-wide modules), this
            table should include these additional mappings, which cannot
            be represented in the entPhysicalTable virtual containment
            tree."
    ::= { entityMapping 3 }

entPhysicalContainsEntry OBJECT-TYPE
    SYNTAX      EntPhysicalContainsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
            "A single container/'containee' relationship."
    INDEX       { entPhysicalIndex, entPhysicalChildIndex }
    ::= { entPhysicalContainsTable 1 }

EntPhysicalContainsEntry ::= SEQUENCE {
      entPhysicalChildIndex     PhysicalIndex
}

entPhysicalChildIndex OBJECT-TYPE
    SYNTAX      PhysicalIndex
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The value of entPhysicalIndex for the contained physical
            entity."

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    ::= { entPhysicalContainsEntry 1 }

-- last change time stamp for the whole MIB
entLastChangeTime OBJECT-TYPE
    SYNTAX      TimeStamp
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
            "The value of sysUpTime at the time a conceptual row is
            created, modified, or deleted in any of these tables:
                    - entPhysicalTable
                    - entLogicalTable
                    - entLPMappingTable
                    - entAliasMappingTable
                    - entPhysicalContainsTable
            "
    ::= { entityGeneral 1 }

-- Entity MIB Trap Definitions
entityMIBTraps      OBJECT IDENTIFIER ::= { entityMIB 2 }
entityMIBTrapPrefix OBJECT IDENTIFIER ::= { entityMIBTraps 0 }

entConfigChange NOTIFICATION-TYPE
    STATUS             current
    DESCRIPTION
            "An entConfigChange notification is generated when the value
            of entLastChangeTime changes.  It can be utilized by an NMS
            to trigger logical/physical entity table maintenance polls.

            An agent should not generate more than one entConfigChange
            'notification-event' in a given time interval (five seconds
            is the suggested default).  A 'notification-event' is the
            transmission of a single trap or inform PDU to a list of
            notification destinations.

            If additional configuration changes occur within the
            throttling period, then notification-events for these
            changes should be suppressed by the agent until the current
            throttling period expires.  At the end of a throttling
            period, one notification-event should be generated if any
            configuration changes occurred since the start of the
            throttling period.  In such a case, another throttling
            period is started right away.

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            An NMS should periodically check the value of
            entLastChangeTime to detect any missed entConfigChange
            notification-events, e.g., due to throttling or transmission
            loss."
   ::= { entityMIBTrapPrefix 1 }

-- conformance information
entityConformance OBJECT IDENTIFIER ::= { entityMIB 3 }

entityCompliances OBJECT IDENTIFIER ::= { entityConformance 1 }
entityGroups      OBJECT IDENTIFIER ::= { entityConformance 2 }

-- compliance statements
entityCompliance MODULE-COMPLIANCE
    STATUS  deprecated
    DESCRIPTION
            "The compliance statement for SNMP entities that implement
            version 1 of the Entity MIB."
    MODULE  -- this module
        MANDATORY-GROUPS {
                           entityPhysicalGroup,
                           entityLogicalGroup,
                           entityMappingGroup,
                           entityGeneralGroup,
                           entityNotificationsGroup
        }
    ::= { entityCompliances 1 }

entity2Compliance MODULE-COMPLIANCE
    STATUS  deprecated
    DESCRIPTION
            "The compliance statement for SNMP entities that implement
            version 2 of the Entity MIB."
    MODULE  -- this module
        MANDATORY-GROUPS {
                           entityPhysicalGroup,
                           entityPhysical2Group,
                           entityGeneralGroup,
                           entityNotificationsGroup
        }
        GROUP entityLogical2Group
        DESCRIPTION
            "Implementation of this group is not mandatory for agents
            that model all MIB object instances within a single naming
            scope."

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        GROUP entityMappingGroup
        DESCRIPTION
            "Implementation of the entPhysicalContainsTable is mandatory
            for all agents.  Implementation of the entLPMappingTable and
            entAliasMappingTables are not mandatory for agents that
            model all MIB object instances within a single naming scope.

            Note that the entAliasMappingTable may be useful for all
            agents; however, implementation of the entityLogicalGroup or
            entityLogical2Group is required to support this table."

        OBJECT entPhysicalSerialNum
        MIN-ACCESS   not-accessible
        DESCRIPTION
            "Read and write access is not required for agents that
            cannot identify serial number information for physical
            entities and/or cannot provide non-volatile storage for
            NMS-assigned serial numbers.

            Write access is not required for agents that can identify
            serial number information for physical entities but cannot
            provide non-volatile storage for NMS-assigned serial
            numbers.

            Write access is not required for physical entities for which
            the associated value of the entPhysicalIsFRU object is equal
            to 'false(2)'."

        OBJECT entPhysicalAlias
        MIN-ACCESS   read-only
        DESCRIPTION
            "Write access is required only if the associated
            entPhysicalClass value is equal to 'chassis(3)'."

        OBJECT entPhysicalAssetID
        MIN-ACCESS   not-accessible
        DESCRIPTION
            "Read and write access is not required for agents that
            cannot provide non-volatile storage for NMS-assigned asset
            identifiers.

            Write access is not required for physical entities for which
            the associated value of the entPhysicalIsFRU object is equal
            to 'false(2)'."

        OBJECT entPhysicalClass
        SYNTAX INTEGER {
            other(1),

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            unknown(2),
            chassis(3),
            backplane(4),
            container(5),
            powerSupply(6),
            fan(7),
            sensor(8),
            module(9),
            port(10),
            stack(11)
        }
        DESCRIPTION
            "Implementation of the 'cpu(12)' enumeration is not
            required."
    ::= { entityCompliances 2 }

entity3Compliance MODULE-COMPLIANCE
    STATUS  deprecated
    DESCRIPTION
            "The compliance statement for SNMP entities that implement
            version 3 of the Entity MIB."
    MODULE  -- this module
        MANDATORY-GROUPS {
                           entityPhysicalGroup,
                           entityPhysical2Group,
                           entityPhysical3Group,
                           entityGeneralGroup,
                           entityNotificationsGroup
        }
        GROUP entityLogical2Group
        DESCRIPTION
            "Implementation of this group is not mandatory for agents
            that model all MIB object instances within a single naming
            scope."

        GROUP entityMappingGroup
        DESCRIPTION
            "Implementation of the entPhysicalContainsTable is mandatory
            for all agents.  Implementation of the entLPMappingTable and
            entAliasMappingTables are not mandatory for agents that
            model all MIB object instances within a single naming scope.

            Note that the entAliasMappingTable may be useful for all
            agents; however, implementation of the entityLogicalGroup or
            entityLogical2Group is required to support this table."

        OBJECT entPhysicalSerialNum
        MIN-ACCESS   not-accessible

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        DESCRIPTION
            "Read and write access is not required for agents that
            cannot identify serial number information for physical
            entities and/or cannot provide non-volatile storage for
            NMS-assigned serial numbers.

            Write access is not required for agents that can identify
            serial number information for physical entities but cannot
            provide non-volatile storage for NMS-assigned serial
            numbers.

            Write access is not required for physical entities for
            which the associated value of the entPhysicalIsFRU object
            is equal to 'false(2)'."

        OBJECT entPhysicalAlias
        MIN-ACCESS   read-only
        DESCRIPTION
            "Write access is required only if the associated
            entPhysicalClass value is equal to 'chassis(3)'."

        OBJECT entPhysicalAssetID
        MIN-ACCESS   not-accessible
        DESCRIPTION
            "Read and write access is not required for agents that
            cannot provide non-volatile storage for NMS-assigned asset
            identifiers.

            Write access is not required for physical entities for which
            the associated value of entPhysicalIsFRU is equal to
            'false(2)'."
    ::= { entityCompliances 3 }

entity4Compliance MODULE-COMPLIANCE
    STATUS  current
    DESCRIPTION
            "The compliance statement for SNMP entities that implement
            the full version 4 (full compliance) of the Entity MIB."
    MODULE  -- this module
        MANDATORY-GROUPS {
                           entityPhysicalGroup,
                           entityPhysical2Group,
                           entityPhysical3Group,
                           entityGeneralGroup,
                           entityNotificationsGroup,
                           entityPhysical4Group
        }
        GROUP entityLogical2Group

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        DESCRIPTION
            "Implementation of this group is not mandatory for agents
            that model all MIB object instances within a single naming
            scope."

        GROUP entityMappingGroup
        DESCRIPTION
            "Implementation of the entPhysicalContainsTable is mandatory
            for all agents.  Implementation of the entLPMappingTable and
            entAliasMappingTables are not mandatory for agents that
            model all MIB object instances within a single naming scope.

            Note that the entAliasMappingTable may be useful for all
            agents; however, implementation of the entityLogicalGroup or
            entityLogical2Group is required to support this table."

        OBJECT entPhysicalSerialNum
        MIN-ACCESS   not-accessible
        DESCRIPTION
            "Read and write access is not required for agents that
            cannot identify serial number information for physical
            entities and/or cannot provide non-volatile storage for
            NMS-assigned serial numbers.

            Write access is not required for agents that can identify
            serial number information for physical entities but cannot
            provide non-volatile storage for NMS-assigned serial
            numbers.

            Write access is not required for physical entities for
            which the associated value of the entPhysicalIsFRU object
            is equal to 'false(2)'."

        OBJECT entPhysicalAlias
        MIN-ACCESS   read-only
        DESCRIPTION
            "Write access is required only if the associated
            entPhysicalClass value is equal to 'chassis(3)'."

        OBJECT entPhysicalAssetID
        MIN-ACCESS   not-accessible
        DESCRIPTION
            "Read and write access is not required for agents that
            cannot provide non-volatile storage for NMS-assigned asset
            identifiers.

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            Write access is not required for physical entities for which
            the associated value of entPhysicalIsFRU is equal to
            'false(2)'."
    ::= { entityCompliances 4 }

entity4CRCompliance MODULE-COMPLIANCE
    STATUS  current
    DESCRIPTION
            "The compliance statement for SNMP entities that implement
            version 4 of the Entity MIB on devices with constrained
            resources."
    MODULE  -- this module
        MANDATORY-GROUPS {
                           entityPhysicalCRGroup,
                           entityPhysical4Group
        }
    ::= { entityCompliances 5 }

-- MIB groupings
entityPhysicalGroup    OBJECT-GROUP
    OBJECTS {
              entPhysicalDescr,
              entPhysicalVendorType,
              entPhysicalContainedIn,
              entPhysicalClass,
              entPhysicalParentRelPos,
              entPhysicalName
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent physical
            system components for which a single agent provides
            management information."
    ::= { entityGroups 1 }

entityLogicalGroup    OBJECT-GROUP
    OBJECTS {
              entLogicalDescr,
              entLogicalType,
              entLogicalCommunity,
              entLogicalTAddress,
              entLogicalTDomain
            }
    STATUS  deprecated

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    DESCRIPTION
            "The collection of objects used to represent the list of
            logical entities for which a single agent provides
            management information."
    ::= { entityGroups 2 }

entityMappingGroup    OBJECT-GROUP
    OBJECTS {
              entLPPhysicalIndex,
              entAliasMappingIdentifier,
              entPhysicalChildIndex
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent the
            associations between multiple logical entities, physical
            components, interfaces, and port identifiers for which a
            single agent provides management information."
    ::= { entityGroups 3 }

entityGeneralGroup    OBJECT-GROUP
    OBJECTS {
              entLastChangeTime
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent general entity
            information for which a single agent provides management
            information."
    ::= { entityGroups 4 }

entityNotificationsGroup NOTIFICATION-GROUP
    NOTIFICATIONS { entConfigChange }
    STATUS        current
    DESCRIPTION
            "The collection of notifications used to indicate Entity MIB
            data consistency and general status information."
    ::= { entityGroups 5 }

entityPhysical2Group    OBJECT-GROUP
    OBJECTS {
              entPhysicalHardwareRev,
              entPhysicalFirmwareRev,
              entPhysicalSoftwareRev,
              entPhysicalSerialNum,
              entPhysicalMfgName,
              entPhysicalModelName,
              entPhysicalAlias,

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              entPhysicalAssetID,
              entPhysicalIsFRU
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent physical
            system components for which a single agent provides
            management information.  This group augments the objects
            contained in the entityPhysicalGroup."
    ::= { entityGroups 6 }

entityLogical2Group    OBJECT-GROUP
    OBJECTS {
              entLogicalDescr,
              entLogicalType,
              entLogicalTAddress,
              entLogicalTDomain,
              entLogicalContextEngineID,
              entLogicalContextName
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent the
            list of logical entities for which a single SNMP entity
            provides management information."
    ::= { entityGroups 7 }

entityPhysical3Group    OBJECT-GROUP
    OBJECTS {
              entPhysicalMfgDate,
              entPhysicalUris
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent physical
            system components for which a single agent provides
            management information.  This group augments the objects
            contained in the entityPhysicalGroup."
    ::= { entityGroups 8 }

entityPhysical4Group    OBJECT-GROUP
    OBJECTS {
              entPhysicalUUID
            }
    STATUS  current

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    DESCRIPTION
            "The collection of objects used to represent physical
            system components for which a single agent provides
            management information.  This group augments the objects
            contained in the entityPhysicalGroup and
            entityPhysicalCRGroup."
    ::= { entityGroups 9 }

entityPhysicalCRGroup    OBJECT-GROUP
    OBJECTS {
              entPhysicalClass,
              entPhysicalName
            }
    STATUS  current
    DESCRIPTION
            "The collection of objects used to represent physical
            system components for constrained resourced devices,
            for which a single agent provides management
            information."
    ::= { entityGroups 10 }

END

3.2. IANA-ENTITY-MIB

   IANA-ENTITY-MIB DEFINITIONS ::= BEGIN

        IMPORTS
          MODULE-IDENTITY, mib-2
            FROM SNMPv2-SMI             -- RFC 2578
          TEXTUAL-CONVENTION
            FROM SNMPv2-TC              -- RFC 2579
          ;

        ianaEntityMIB MODULE-IDENTITY
          LAST-UPDATED "201304050000Z"  -- April 5, 2013
          ORGANIZATION "IANA"
          CONTACT-INFO
                       "Internet Assigned Numbers Authority
                        Postal: ICANN
                                12025 Waterfront Drive, Suite 300
                                Los Angeles, CA 90094-2536

                        Phone: +1-310-301-5800
                        EMail: [email protected]"

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          DESCRIPTION
            "This MIB module defines a TEXTUAL-CONVENTION that provides
            an indication of the general hardware type of a particular
            physical entity.

            Copyright (c) 2013 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).

            The initial version of this MIB module was published in
            RFC 6933; for full legal notices see the RFC itself."

          REVISION     "201304050000Z"  -- April 5, 2013
          DESCRIPTION  "Initial version of this MIB as published in
                        RFC 6933."

          ::= { mib-2 216 }

        -- Textual Conventions

   IANAPhysicalClass ::= TEXTUAL-CONVENTION
       STATUS            current
       DESCRIPTION
               "An enumerated value that provides an indication of the
               general hardware type of a particular physical entity.
               There are no restrictions as to the number of
               entPhysicalEntries of each entPhysicalClass, which must
               be instantiated by an agent.

               The enumeration 'other' is applicable if the physical
               entity class is known but does not match any of the
               supported values.

               The enumeration 'unknown' is applicable if the physical
               entity class is unknown to the agent.

               The enumeration 'chassis' is applicable if the physical
               entity class is an overall container for networking
               equipment.  Any class of physical entity, except a stack,
               may be contained within a chassis; a chassis may only
               be contained within a stack.

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               The enumeration 'backplane' is applicable if the physical
               entity 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
               agent may model a backplane as a single physical entity,
               which is actually implemented as multiple discrete
               physical components (within a chassis or stack).

               The enumeration 'container' is applicable if the
               physical entity 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 entities should be modeled within
               a container entity, such as field-replaceable modules,
               fans, or power supplies.  Note that all known containers
               should be modeled by the agent, including empty
               containers.

               The enumeration 'powerSupply' is applicable if the
               physical entity class is a power-supplying component.

               The enumeration 'fan' is applicable if the physical
               entity class is a fan or other heat-reduction component.

               The enumeration 'sensor' is applicable if the physical
               entity class is some sort of sensor, such as a
               temperature sensor within a router chassis.

               The enumeration 'module' is applicable if the physical
               entity class is some sort of self-contained sub-system.
               If the enumeration 'module' is removable, then it should
               be modeled within a container entity; otherwise, it
               should be modeled directly within another physical
               entity (e.g., a chassis or another module).

               The enumeration 'port' is applicable if the physical
               entity class is some sort of networking port, capable
               of receiving and/or transmitting networking traffic.

               The enumeration 'stack' is applicable if the physical
               entity 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

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               modeled within any other physical entities, but a stack
               may be contained within another stack.  Only chassis
               entities should be contained within a stack.

               The enumeration 'cpu' is applicable if the physical
               entity class is some sort of central processing unit.

               The enumeration 'energyObject' is applicable if the
               physical entity 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.

               The enumeration 'battery' is applicable if the physical
               entity class is some sort of battery."

       SYNTAX      INTEGER  {
          other(1),
          unknown(2),
          chassis(3),
          backplane(4),
          container(5), -- e.g., chassis slot or daughter-card holder
          powerSupply(6),
          fan(7),
          sensor(8),
          module(9),        -- e.g., plug-in card or daughter-card
          port(10),
          stack(11),        -- e.g., stack of multiple chassis entities
          cpu(12),
          energyObject(13),
          battery (14)
       }

   END

3.3. UUID-TC-MIB

   UUID-TC-MIB DEFINITIONS ::= BEGIN

        IMPORTS
          MODULE-IDENTITY, mib-2
            FROM SNMPv2-SMI             -- RFC 2578
          TEXTUAL-CONVENTION
            FROM SNMPv2-TC              -- RFC 2579
          ;

        uuidTCMIB MODULE-IDENTITY

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          LAST-UPDATED "201304050000Z"  -- April 5, 2013
          ORGANIZATION "IETF Energy Management Working Group"
          CONTACT-INFO "WG Email: [email protected]
                        Mailing list subscription info:
                        http://www.ietf.org/mailman/listinfo/eman

                        Dan Romascanu
                        Avaya
                        Park Atidim, Bldg. #3
                        Tel Aviv, 61581
                        Israel
                        Phone: +972-3-6458414
                        Email: [email protected]

                        Juergen Quittek
                        NEC Europe Ltd.
                        Network Research Division
                        Kurfuersten-Anlage 36
                        Heidelberg  69115
                        Germany
                        Phone: +49 6221 4342-115
                        Email: [email protected]

                        Mouli Chandramouli
                        Cisco Systems, Inc.
                        Sarjapur Outer Ring Road
                        Bangalore 560103
                        India
                        Phone: +91 80 4429 2409
                        Email: [email protected]"

          DESCRIPTION
                     "This MIB module defines TEXTUAL-CONVENTIONs
                      representing Universally Unique IDentifiers
                      (UUIDs).

                      Copyright (c) 2013 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)."

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          REVISION     "201304050000Z"  -- April 5, 2013
          DESCRIPTION  "Initial version of this MIB as published in
                        RFC 6933."

          ::= { mib-2 217 }

        -- Textual Conventions

   UUID ::= TEXTUAL-CONVENTION
       DISPLAY-HINT    "4x-2x-2x-1x1x-6x"
       STATUS          current
       DESCRIPTION
            "Universally Unique Identifier information.  The syntax must
             conform to RFC 4122, Section 4.1."

           SYNTAX      OCTET STRING (SIZE (16))

   UUIDorZero ::= TEXTUAL-CONVENTION
       DISPLAY-HINT    "4x-2x-2x-1x1x-6x"
       STATUS          current
       DESCRIPTION
            "Universally Unique Identifier information.  The syntax must
             conform to RFC 4122, Section 4.1.

             The semantics of the value zero-length OCTET STRING are
             object-specific and must therefore be defined as part of
             the description of any object that uses this syntax."

           SYNTAX      OCTET STRING (SIZE (0|16))

   END

4.  Usage Examples

   The following sections iterate the instance values for two example
   networking devices.  These examples are kept simple to make them
   more understandable.  Auxiliary components such as fans, sensors,
   empty slots, and sub-modules are not shown but might be modeled in
   real implementations.

4.1.  Router/Bridge

   The first example is a router containing two slots.  Each slot
   contains a 3-port router/bridge module.  Each port is represented
   in the ifTable.  There are two logical instances of OSPF running and
   two logical bridges:

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    Physical entities -- entPhysicalTable:
       1 Field-replaceable physical chassis:
         entPhysicalDescr.1 ==             'Acme Chassis Model 100'
         entPhysicalVendorType.1 ==        acmeProducts.chassisTypes.1
         entPhysicalContainedIn.1 ==       0
         entPhysicalClass.1 ==             chassis(3)
         entPhysicalParentRelPos.1 ==      0
         entPhysicalName.1 ==              '100-A'
         entPhysicalHardwareRev.1 ==       'A(1.00.02)'
         entPhysicalSoftwareRev.1 ==       ''
         entPhysicalFirmwareRev.1 ==       ''
         entPhysicalSerialNum.1 ==         'C100076544'
         entPhysicalMfgName.1 ==           'Acme'
         entPhysicalModelName.1 ==         '100'
         entPhysicalAlias.1 ==             'cl-SJ17-3-006:rack1:rtr-U3'
         entPhysicalAssetID.1 ==           '0007372293'
         entPhysicalIsFRU.1 ==             true(1)
         entPhysicalMfgDate.1 ==           '2002-5-26,13:30:30.0,-4:0'
         entPhysicalUris.1 ==              'URN:CLEI:CNME120ARA'
       2 slots within the chassis:
         entPhysicalDescr.2 ==             'Acme Chassis Slot Type AA'
         entPhysicalVendorType.2  ==       acmeProducts.slotTypes.1
         entPhysicalContainedIn.2 ==       1
         entPhysicalClass.2 ==             container(5)
         entPhysicalParentRelPos.2 ==      1
         entPhysicalName.2 ==              'S1'
         entPhysicalHardwareRev.2 ==       'B(1.00.01)'
         entPhysicalSoftwareRev.2 ==       ''
         entPhysicalFirmwareRev.2 ==       ''
         entPhysicalSerialNum.2 ==         ''
         entPhysicalMfgName.2 ==           'Acme'
         entPhysicalModelName.2 ==         'AA'
         entPhysicalAlias.2 ==             ''
         entPhysicalAssetID.2 ==           ''
         entPhysicalIsFRU.2 ==             false(2)
         entPhysicalMfgDate.2 ==           '2002-7-26,12:22:12.0,-4:0'
         entPhysicalUris.2 ==              'URN:CLEI:CNME123ARA'

         entPhysicalDescr.3 ==             'Acme Chassis Slot Type AA'
         entPhysicalVendorType.3 =         acmeProducts.slotTypes.1
         entPhysicalContainedIn.3 ==       1
         entPhysicalClass.3 ==             container(5)
         entPhysicalParentRelPos.3 ==      2
         entPhysicalName.3 ==              'S2'
         entPhysicalHardwareRev.3 ==       '1.00.07'
         entPhysicalSoftwareRev.3 ==       ''
         entPhysicalFirmwareRev.3 ==       ''
         entPhysicalSerialNum.3 ==         ''

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         entPhysicalMfgName.3 ==           'Acme'
         entPhysicalModelName.3 ==         'AA'
         entPhysicalAlias.3 ==             ''
         entPhysicalAssetID.3 ==           ''
         entPhysicalIsFRU.3 ==             false(2)
         entPhysicalMfgDate.3 ==           '2002-7-26,12:12:12.0,-4:0'
         entPhysicalUris.3 ==              'URN:CLEI:CNME123ARA'

       2 Field-replaceable modules:
       Slot 1 contains a module with 3 ports:
         entPhysicalDescr.4 ==             'Acme Router-100'
         entPhysicalVendorType.4  ==       acmeProducts.moduleTypes.14
         entPhysicalContainedIn.4 ==       2
         entPhysicalClass.4 ==             module(9)
         entPhysicalParentRelPos.4 ==      1
         entPhysicalName.4 ==              'M1'
         entPhysicalHardwareRev.4 ==       '1.00.07'
         entPhysicalSoftwareRev.4 ==       '1.4.1'
         entPhysicalFirmwareRev.4 ==       'A(1.1)'
         entPhysicalSerialNum.4 ==         'C100087363'
         entPhysicalMfgName.4 ==           'Acme'
         entPhysicalModelName.4 ==         'R100-FE'
         entPhysicalAlias.4 ==             'rtr-U3:m1:SJ17-3-eng'
         entPhysicalAssetID.4 ==           '0007372462'
         entPhysicalIsFRU.4 ==             true(1)
         entPhysicalMfgDate.4 ==           '2003-7-18,13:30:30.0,-4:0'
         entPhysicalUris.4 ==              'URN:CLEI:CNRU123CAA'

         entPhysicalDescr.5 ==             'Acme Ethernet-100 Port'
         entPhysicalVendorType.5  ==       acmeProducts.portTypes.2
         entPhysicalContainedIn.5 ==       4
         entPhysicalClass.5 ==             port(10)
         entPhysicalParentRelPos.5 ==      1
         entPhysicalName.5 ==              'P1'
         entPhysicalHardwareRev.5 ==       'G(1.02)'
         entPhysicalSoftwareRev.5 ==       ''
         entPhysicalFirmwareRev.5 ==       '1.1'
         entPhysicalSerialNum.5 ==         ''
         entPhysicalMfgName.5 ==           'Acme'
         entPhysicalModelName.5 ==         'FE-100'
         entPhysicalAlias.5 ==             ''
         entPhysicalAssetID.5 ==           ''
         entPhysicalIsFRU.5 ==             false(2)
         entPhysicalMfgDate.5 ==           '2003-7-18,14:20:22.0,-4:0'
         entPhysicalUris.5 ==              'URN:CLEI:CNMES23ARA'

         entPhysicalDescr.6 ==             'Acme Ethernet-100 Port'
         entPhysicalVendorType.6  ==       acmeProducts.portTypes.2

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         entPhysicalContainedIn.6 ==       4
         entPhysicalClass.6 ==             port(10)
         entPhysicalParentRelPos.6 ==      2
         entPhysicalName.6 ==              'P2'
         entPhysicalHardwareRev.6 ==       'G(1.02)'
         entPhysicalSoftwareRev.6 ==       ''
         entPhysicalFirmwareRev.6 ==       '1.1'
         entPhysicalSerialNum.6 ==         ''
         entPhysicalMfgName.6 ==           'Acme'
         entPhysicalModelName.6 ==         'FE-100'
         entPhysicalAlias.6 ==             ''
         entPhysicalAssetID.6 ==           ''
         entPhysicalIsFRU.6 ==             false(2)
         entPhysicalMfgDate.6 ==           '2003-7-19,10:15:15.0,-4:0'
         entPhysicalUris.6 ==              'URN:CLEI:CNMES23ARA'

         entPhysicalDescr.7 ==             'Acme Router-100 FDDI-Port'
         entPhysicalVendorType.7  ==       acmeProducts.portTypes.3
         entPhysicalContainedIn.7 ==       4
         entPhysicalClass.7 ==             port(10)
         entPhysicalParentRelPos.7 ==      3
         entPhysicalName.7 ==              'P3'
         entPhysicalHardwareRev.7 ==       'B(1.03)'
         entPhysicalSoftwareRev.7 ==       '2.5.1'
         entPhysicalFirmwareRev.7 ==       '2.5F'
         entPhysicalSerialNum.7 ==         ''
         entPhysicalMfgName.7 ==           'Acme'
         entPhysicalModelName.7 ==         'FDDI-100'
         entPhysicalAlias.7 ==             ''
         entPhysicalAssetID.7 ==           ''
         entPhysicalIsFRU.7 ==             false(2)

      Slot 2 contains another 3-port module:
         entPhysicalDescr.8 ==             'Acme Router-100 Comm Module'
         entPhysicalVendorType.8  ==       acmeProducts.moduleTypes.15
         entPhysicalContainedIn.8 ==       3
         entPhysicalClass.8 ==             module(9)
         entPhysicalParentRelPos.8 ==      1
         entPhysicalName.8 ==              'M2'
         entPhysicalHardwareRev.8 ==       '2.01.00'
         entPhysicalSoftwareRev.8 ==       '3.0.7'
         entPhysicalFirmwareRev.8 ==       'A(1.2)'
         entPhysicalSerialNum.8 ==         'C100098732'
         entPhysicalMfgName.8 ==           'Acme'
         entPhysicalModelName.8 ==         'C100'
         entPhysicalAlias.8 ==             'rtr-U3:m2:SJ17-2-eng'
         entPhysicalAssetID.8 ==           '0007373982'
         entPhysicalIsFRU.8 ==             true(1)

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         entPhysicalMfgDate.8 ==           '2002-5-26,13:30:15.0,-4:0'
         entPhysicalUris.8 ==              'URN:CLEI:CNRT321MAA'

         entPhysicalDescr.9 ==             'Acme Fddi-100 Port'
         entPhysicalVendorType.9 ==        acmeProducts.portTypes.5
         entPhysicalContainedIn.9 ==       8
         entPhysicalClass.9 ==             port(10)
         entPhysicalParentRelPos.9 ==      1
         entPhysicalName.9 ==              'FDDI Primary'
         entPhysicalHardwareRev.9 ==       'CC(1.07)'
         entPhysicalSoftwareRev.9 ==       '2.0.34'
         entPhysicalFirmwareRev.9 ==       '1.1'
         entPhysicalSerialNum.9 ==         ''
         entPhysicalMfgName.9 ==           'Acme'
         entPhysicalModelName.9 ==         'FDDI-100'
         entPhysicalAlias.9 ==             ''
         entPhysicalAssetID.9 ==           ''
         entPhysicalIsFRU.9 ==             false(2)

         entPhysicalDescr.10 ==            'Acme Ethernet-100 Port'
         entPhysicalVendorType.10 ==       acmeProducts.portTypes.2
         entPhysicalContainedIn.10 ==      8
         entPhysicalClass.10 ==            port(10)
         entPhysicalParentRelPos.10 ==     2
         entPhysicalName.10 ==             'Ethernet A'
         entPhysicalHardwareRev.10 ==      'G(1.04)'
         entPhysicalSoftwareRev.10 ==      ''
         entPhysicalFirmwareRev.10 ==      '1.3'
         entPhysicalSerialNum.10 ==        ''
         entPhysicalMfgName.10 ==          'Acme'
         entPhysicalModelName.10 ==        'FE-100'
         entPhysicalAlias.10 ==            ''
         entPhysicalAssetID.10 ==          ''
         entPhysicalIsFRU.10 ==            false(2)
         entPhysicalMfgDate.10 ==          '2002-7-26,13:30:15.0,-4:0'
         entPhysicalUris.10 ==             'URN:CLEI:CNMES23ARA'

         entPhysicalDescr.11 ==            'Acme Ethernet-100 Port'
         entPhysicalVendorType.11 ==       acmeProducts.portTypes.2
         entPhysicalContainedIn.11 ==      8
         entPhysicalClass.11 ==            port(10)
         entPhysicalParentRelPos.11 ==     3
         entPhysicalName.11 ==             'Ethernet B'
         entPhysicalHardwareRev.11 ==      'G(1.04)'
         entPhysicalSoftwareRev.11 ==      ''
         entPhysicalFirmwareRev.11 ==      '1.3'
         entPhysicalSerialNum.11 ==        ''
         entPhysicalMfgName.11 ==          'Acme'

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         entPhysicalModelName.11 ==        'FE-100'
         entPhysicalAlias.11 ==            ''
         entPhysicalAssetID.11 ==          ''
         entPhysicalIsFRU.11 ==            false(2)
         entPhysicalMfgDate.11 ==          '2002-8-16,15:35:15.0,-4:0'
         entPhysicalUris.11 ==             'URN:CLEI:CNMES23ARA'

      Logical entities -- entLogicalTable; no SNMPv3 support
       2 OSPF instances:
         entLogicalDescr.1 ==              'Acme OSPF v1.1'
         entLogicalType.1 ==               ospf
         entLogicalCommunity.1 ==          'public-ospf1'
         entLogicalTAddress.1 ==           192.0.2.1:161
         entLogicalTDomain.1 ==            snmpUDPDomain
         entLogicalContextEngineID.1 ==    ''
         entLogicalContextName.1 ==        ''

         entLogicalDescr.2 ==              'Acme OSPF v1.1'
         entLogicalType.2 ==               ospf
         entLogicalCommunity.2 ==          'public-ospf2'
         entLogicalTAddress.2 ==           192.0.2.1:161
         entLogicalTDomain.2 ==            snmpUDPDomain
         entLogicalContextEngineID.2 ==    ''
         entLogicalContextName.2 ==        ''

       2 logical bridges:
         entLogicalDescr.3 ==              'Acme Bridge v2.1.1'
         entLogicalType.3  ==              dot1dBridge
         entLogicalCommunity.3 ==          'public-bridge1'
         entLogicalTAddress.3 ==           192.0.2.1:161
         entLogicalTDomain.3 ==            snmpUDPDomain
         entLogicalContextEngineID.3 ==    ''
         entLogicalContextName.3 ==        ''

         entLogicalDescr.4 ==              'Acme Bridge v2.1.1'
         entLogicalType.4 ==               dot1dBridge
         entLogicalCommunity.4 ==          'public-bridge2'
         entLogicalTAddress.4 ==           192.0.2.1:161
         entLogicalTDomain.4 ==            snmpUDPDomain
         entLogicalContextEngineID.4 ==    ''
         entLogicalContextName.4 ==        ''

   Logical to Physical Mappings:
     1st OSPF instance: uses module 1-port 1
         entLPPhysicalIndex.1.5 ==         5

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     2nd OSPF instance: uses module 2-port 1
         entLPPhysicalIndex.2.9 ==         9

     1st bridge group: uses module 1, all ports

     Note that these mappings are included in the table because
     another logical entity (1st OSPF) utilizes one of the
     ports.  If this were not the case, then a single mapping
     to the module (e.g., entLPPhysicalIndex.3.4) would be
     present instead.

         entLPPhysicalIndex.3.5 ==         5
         entLPPhysicalIndex.3.6 ==         6
         entLPPhysicalIndex.3.7 ==         7

     2nd bridge group: uses module 2, all ports
         entLPPhysicalIndex.4.9  ==        9
         entLPPhysicalIndex.4.10 ==        10
         entLPPhysicalIndex.4.11 ==        11

   Physical to Logical to MIB Alias Mappings -- entAliasMappingTable:
     Example 1: ifIndex values are global to all logical entities
         entAliasMappingIdentifier.5.0 ==  ifIndex.1
         entAliasMappingIdentifier.6.0 ==  ifIndex.2
         entAliasMappingIdentifier.7.0 ==  ifIndex.3
         entAliasMappingIdentifier.9.0 ==  ifIndex.4
         entAliasMappingIdentifier.10.0 == ifIndex.5
         entAliasMappingIdentifier.11.0 == ifIndex.6

     Example 2: ifIndex values are not shared by all logical entities;
            (Bridge-1 uses ifIndex values 101 - 103 and Bridge-2 uses
            ifIndex values 204-206.)
            entAliasMappingIdentifier.5.0 ==  ifIndex.1
            entAliasMappingIdentifier.5.3 ==  ifIndex.101
            entAliasMappingIdentifier.6.0 ==  ifIndex.2
            entAliasMappingIdentifier.6.3 ==  ifIndex.102
            entAliasMappingIdentifier.7.0 ==  ifIndex.3
            entAliasMappingIdentifier.7.3 ==  ifIndex.103
            entAliasMappingIdentifier.9.0 ==  ifIndex.4
            entAliasMappingIdentifier.9.4 ==  ifIndex.204
            entAliasMappingIdentifier.10.0 == ifIndex.5
            entAliasMappingIdentifier.10.4 == ifIndex.205
            entAliasMappingIdentifier.11.0 == ifIndex.6
            entAliasMappingIdentifier.11.4 == ifIndex.206

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   Physical Containment Tree -- entPhysicalContainsTable
     chassis has two containers:
         entPhysicalChildIndex.1.2 ==      2
         entPhysicalChildIndex.1.3 ==      3

     container 1 has a module:
         entPhysicalChildIndex.2.4 ==      4

     container 2 has a module:
         entPhysicalChildIndex.3.8 ==      8

     module 1 has 3 ports:
         entPhysicalChildIndex.4.5 ==      5
         entPhysicalChildIndex.4.6 ==      6
         entPhysicalChildIndex.4.7 ==      7

     module 2 has 3 ports:
         entPhysicalChildIndex.8.9 ==      9
         entPhysicalChildIndex.8.10 ==     10
         entPhysicalChildIndex.8.11 ==     11

4.2.  Repeaters

   The second example is a 3-slot hub with 2 backplane ethernet
   segments.  Slot three is empty, and the remaining slots contain
   ethernet repeater modules.

   Note that this example assumes an older Repeater MIB implementation
   [RFC1516] rather than the new Repeater MIB [RFC2108].  The new
   version contains an object called 'rptrPortRptrId', which should be
   used to identify repeater port groupings, rather than using community
   strings or contexts.

   Physical entities -- entPhysicalTable:
      1 Field-replaceable physical chassis:
         entPhysicalDescr.1 ==       'Acme Chassis Model 110'
         entPhysicalVendorType.1 ==  acmeProducts.chassisTypes.2
         entPhysicalContainedIn.1 == 0
         entPhysicalClass.1 ==       chassis(3)
         entPhysicalParentRelPos.1 ==0
         entPhysicalName.1 ==        '110-B'
         entPhysicalHardwareRev.1 == 'A(1.02.00)'
         entPhysicalSoftwareRev.1 == ''
         entPhysicalFirmwareRev.1 == ''
         entPhysicalSerialNum.1 ==   'C100079294'
         entPhysicalMfgName.1 ==     'Acme'
         entPhysicalModelName.1 ==   '110'
         entPhysicalAlias.1 ==       'bldg09:floor1:rptr18:0067eea0229f'

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         entPhysicalAssetID.1 ==     '0007386327'
         entPhysicalIsFRU.1 ==       true(1)

      2 Chassis Ethernet Backplanes:
         entPhysicalDescr.2 ==          'Acme Ethernet Backplane Type A'
         entPhysicalVendorType.2 ==     acmeProducts.backplaneTypes.1
         entPhysicalContainedIn.2 ==    1
         entPhysicalClass.2 ==          backplane(4)
         entPhysicalParentRelPos.2 ==   1
         entPhysicalName.2 ==           'B1'
         entPhysicalHardwareRev.2 ==    'A(2.04.01)'
         entPhysicalSoftwareRev.2 ==    ''
         entPhysicalFirmwareRev.2 ==    ''
         entPhysicalSerialNum.2 ==      ''
         entPhysicalMfgName.2 ==        'Acme'
         entPhysicalModelName.2 ==      'BK-A'
         entPhysicalAlias.2 ==          ''
         entPhysicalAssetID.2 ==        ''
         entPhysicalIsFRU.2 ==          false(2)

         entPhysicalDescr.3 ==          'Acme Ethernet Backplane Type A'
         entPhysicalVendorType.3  ==    acmeProducts.backplaneTypes.1
         entPhysicalContainedIn.3 ==    1
         entPhysicalClass.3 ==          backplane(4)
         entPhysicalParentRelPos.3 ==   2
         entPhysicalName.3 ==           'B2'
         entPhysicalHardwareRev.3 ==    'A(2.04.01)'
         entPhysicalSoftwareRev.3 ==    ''
         entPhysicalFirmwareRev.3 ==    ''
         entPhysicalSerialNum.3 ==      ''
         entPhysicalMfgName.3 ==        'Acme'
         entPhysicalModelName.3 ==      'BK-A'
         entPhysicalAlias.3 ==          ''
         entPhysicalAssetID.3 ==        ''
         entPhysicalIsFRU.3 ==          false(2)

      3 slots within the chassis:
         entPhysicalDescr.4 ==          'Acme Hub Slot Type RB'
         entPhysicalVendorType.4  ==    acmeProducts.slotTypes.5
         entPhysicalContainedIn.4 ==    1
         entPhysicalClass.4 ==          container(5)
         entPhysicalParentRelPos.4 ==   1
         entPhysicalName.4 ==           'Slot 1'
         entPhysicalHardwareRev.4 ==    'B(1.00.03)'
         entPhysicalSoftwareRev.4 ==    ''
         entPhysicalFirmwareRev.4 ==    ''
         entPhysicalSerialNum.4 ==      ''
         entPhysicalMfgName.4 ==        'Acme'

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         entPhysicalModelName.4 ==      'RB'
         entPhysicalAlias.4 ==          ''
         entPhysicalAssetID.4 ==        ''
         entPhysicalIsFRU.4 ==          false(2)

         entPhysicalDescr.5 ==          'Acme Hub Slot Type RB'
         entPhysicalVendorType.5  ==    acmeProducts.slotTypes.5
         entPhysicalContainedIn.5 ==    1
         entPhysicalClass.5 ==          container(5)
         entPhysicalParentRelPos.5 ==   2
         entPhysicalName.5 ==           'Slot 2'
         entPhysicalHardwareRev.5 ==    'B(1.00.03)'
         entPhysicalSoftwareRev.5 ==    ''
         entPhysicalFirmwareRev.5 ==    ''
         entPhysicalSerialNum.5 ==      ''
         entPhysicalMfgName.5 ==        'Acme'
         entPhysicalModelName.5 ==      'RB'
         entPhysicalAlias.5 ==          ''
         entPhysicalAssetID.5 ==        ''
         entPhysicalIsFRU.5 ==          false(2)

         entPhysicalDescr.6 ==          'Acme Hub Slot Type RB'
         entPhysicalVendorType.6  ==    acmeProducts.slotTypes.5
         entPhysicalContainedIn.6 ==    1
         entPhysicalClass.6 ==          container(5)
         entPhysicalParentRelPos.6 ==   3
         entPhysicalName.6 ==           'Slot 3'
         entPhysicalHardwareRev.6 ==    'B(1.00.03)'
         entPhysicalSoftwareRev.6 ==    ''
         entPhysicalFirmwareRev.6 ==    ''
         entPhysicalSerialNum.6 ==      ''
         entPhysicalMfgName.6 ==        'Acme'
         entPhysicalModelName.6 ==      'RB'
         entPhysicalAlias.6 ==          ''
         entPhysicalAssetID.6 ==        ''
         entPhysicalIsFRU.6 ==          false(2)

      Slot 1 contains a plug-in module with 4 10-BaseT ports:
         entPhysicalDescr.7  ==         'Acme 10Base-T Module 114'
         entPhysicalVendorType.7 ==     acmeProducts.moduleTypes.32
         entPhysicalContainedIn.7  ==   4
         entPhysicalClass.7 ==          module(9)
         entPhysicalParentRelPos.7 ==   1
         entPhysicalName.7 ==           'M1'
         entPhysicalHardwareRev.7 ==    'A(1.02.01)'
         entPhysicalSoftwareRev.7 ==    '1.7.2'
         entPhysicalFirmwareRev.7 ==    'A(1.5)'
         entPhysicalSerialNum.7 ==      'C100096244'

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         entPhysicalMfgName.7 ==        'Acme'
         entPhysicalModelName.7 =       '114'
         entPhysicalAlias.7 ==          'bldg09:floor1:eng'
         entPhysicalAssetID.7 ==        '0007962951'
         entPhysicalIsFRU.7 ==          true(1)

         entPhysicalDescr.8 ==          'Acme 10Base-T Port RB'
         entPhysicalVendorType.8 ==     acmeProducts.portTypes.10
         entPhysicalContainedIn.8  ==   7
         entPhysicalClass.8 ==          port(10)
         entPhysicalParentRelPos.8 ==   1
         entPhysicalName.8 ==           'Ethernet-A'
         entPhysicalHardwareRev.8 ==    'A(1.04F)'
         entPhysicalSoftwareRev.8 ==    ''
         entPhysicalFirmwareRev.8 ==    '1.4'
         entPhysicalSerialNum.8 ==      ''
         entPhysicalMfgName.8 ==        'Acme'
         entPhysicalModelName.8 ==      'RB'
         entPhysicalAlias.8 ==          ''
         entPhysicalAssetID.8 ==        ''
         entPhysicalIsFRU.8 ==          false(2)

         entPhysicalDescr.9  ==         'Acme 10Base-T Port RB'
         entPhysicalVendorType.9 ==     acmeProducts.portTypes.10
         entPhysicalContainedIn.9 ==    7
         entPhysicalClass.9 ==          port(10)
         entPhysicalParentRelPos.9 ==   2
         entPhysicalName.9 ==           'Ethernet-B'
         entPhysicalHardwareRev.9 ==    'A(1.04F)'
         entPhysicalSoftwareRev.9 ==    ''
         entPhysicalFirmwareRev.9 ==    '1.4'
         entPhysicalSerialNum.9 ==      ''
         entPhysicalMfgName.9 ==        'Acme'
         entPhysicalModelName.9 =       'RB'
         entPhysicalAlias.9 ==          ''
         entPhysicalAssetID.9 ==        ''
         entPhysicalIsFRU.9 ==          false(2)

         entPhysicalDescr.10 ==         'Acme 10Base-T Port RB'
         entPhysicalVendorType.10 ==    acmeProducts.portTypes.10
         entPhysicalContainedIn.10 ==   7
         entPhysicalClass.10 ==         port(10)
         entPhysicalParentRelPos.10 ==  3
         entPhysicalName.10 ==          'Ethernet-C'
         entPhysicalHardwareRev.10 ==   'B(1.02.07)'
         entPhysicalSoftwareRev.10 ==   ''
         entPhysicalFirmwareRev.10 ==   '1.4'
         entPhysicalSerialNum.10 ==     ''

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         entPhysicalMfgName.10 ==       'Acme'
         entPhysicalModelName.10 ==     'RB'
         entPhysicalAlias.10 ==         ''
         entPhysicalAssetID.10 ==       ''
         entPhysicalIsFRU.10 ==         false(2)

         entPhysicalDescr.11 ==         'Acme 10Base-T Port RB'
         entPhysicalVendorType.11  ==   acmeProducts.portTypes.10
         entPhysicalContainedIn.11 ==   7
         entPhysicalClass.11 ==         port(10)
         entPhysicalParentRelPos.11 ==  4
         entPhysicalName.11 ==          'Ethernet-D'
         entPhysicalHardwareRev.11 ==   'B(1.02.07)'
         entPhysicalSoftwareRev.11 ==   ''
         entPhysicalFirmwareRev.11 ==   '1.4'
         entPhysicalSerialNum.11 ==     ''
         entPhysicalMfgName.11 ==       'Acme'
         entPhysicalModelName.11 ==     'RB'
         entPhysicalAlias.11 ==         ''
         entPhysicalAssetID.11 ==       ''
         entPhysicalIsFRU.11 ==         false(2)

      Slot 2 contains another ethernet module with 2 ports.
         entPhysicalDescr.12 ==         'Acme 10Base-T Module Model 4'
         entPhysicalVendorType.12 ==    acmeProducts.moduleTypes.30
         entPhysicalContainedIn.12 =    5
         entPhysicalClass.12 ==         module(9)
         entPhysicalParentRelPos.12 ==  1
         entPhysicalName.12 ==          'M2'
         entPhysicalHardwareRev.12 ==   'A(1.01.07)'
         entPhysicalSoftwareRev.12 ==   '1.8.4'
         entPhysicalFirmwareRev.12 ==   'A(1.8)'
         entPhysicalSerialNum.12 ==     'C100102384'
         entPhysicalMfgName.12 ==       'Acme'
         entPhysicalModelName.12 ==     '4'
         entPhysicalAlias.12 ==         'bldg09:floor1:devtest'
         entPhysicalAssetID.12 ==       '0007968462'
         entPhysicalIsFRU.12 ==         true(1)

         entPhysicalDescr.13 ==         'Acme 802.3 AUI Port'
         entPhysicalVendorType.13  ==   acmeProducts.portTypes.11
         entPhysicalContainedIn.13 ==   12
         entPhysicalClass.13 ==         port(10)
         entPhysicalParentRelPos.13 ==  1
         entPhysicalName.13 ==          'AUI'
         entPhysicalHardwareRev.13 ==   'A(1.06F)'
         entPhysicalSoftwareRev.13 ==   ''
         entPhysicalFirmwareRev.13 ==   '1.5'

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         entPhysicalSerialNum.13 ==     ''
         entPhysicalMfgName.13 ==       'Acme'
         entPhysicalModelName.13 ==     ''
         entPhysicalAlias.13 ==         ''
         entPhysicalAssetID.13 ==       ''
         entPhysicalIsFRU.13 ==         false(2)

         entPhysicalDescr.14 ==         'Acme 10Base-T Port RD'
         entPhysicalVendorType.14  ==   acmeProducts.portTypes.14
         entPhysicalContainedIn.14 ==   12
         entPhysicalClass.14 ==         port(10)
         entPhysicalParentRelPos.14 ==  2
         entPhysicalName.14 ==          'E2'
         entPhysicalHardwareRev.14 ==   'B(1.01.02)'
         entPhysicalSoftwareRev.14 ==   ''
         entPhysicalFirmwareRev.14 ==   '2.1'
         entPhysicalSerialNum.14 ==     ''
         entPhysicalMfgName.14 ==       'Acme'
         entPhysicalModelName.14 ==     ''
         entPhysicalAlias.14 ==         ''
         entPhysicalAssetID.14 ==       ''
         entPhysicalIsFRU.14 ==         false(2)

   Logical entities -- entLogicalTable; with SNMPv3 support
      Repeater 1--comprised of any ports attached to backplane 1
         entLogicalDescr.1 ==           'Acme repeater v3.1'
         entLogicalType.1  ==           snmpDot3RptrMgt
         entLogicalCommunity.1          'public-repeater1'
         entLogicalTAddress.1 ==        192.0.2.1:161
         entLogicalTDomain.1 ==         snmpUDPDomain
         entLogicalContextEngineID.1 == '80000777017c7d7e7f'H
         entLogicalContextName.1 ==     'repeater1'

      Repeater 2--comprised of any ports attached to backplane 2:
         entLogicalDescr.2 ==           'Acme repeater v3.1'
         entLogicalType.2  ==           snmpDot3RptrMgt
         entLogicalCommunity.2 ==       'public-repeater2'
         entLogicalTAddress.2 ==        192.0.2.1:161
         entLogicalTDomain.2 ==         snmpUDPDomain
         entLogicalContextEngineID.2 == '80000777017c7d7e7f'H
         entLogicalContextName.2 ==     'repeater2'

   Logical to Physical Mappings -- entLPMappingTable:

     repeater1 uses backplane 1, slot 1-ports 1 & 2, slot 2-port 1

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      Note that a mapping to the module is not included,
      because this example represents a port-switchable hub.
      Even though all ports on the module could belong to the
      same repeater as a matter of configuration, the LP port
      mappings should not be replaced dynamically with a single
      mapping for the module (e.g., entLPPhysicalIndex.1.7).
      If all ports on the module shared a single backplane connection,
      then a single mapping for the module would be more appropriate.

        entLPPhysicalIndex.1.2 ==       2
        entLPPhysicalIndex.1.8 ==       8
        entLPPhysicalIndex.1.9 ==       9
        entLPPhysicalIndex.1.13 ==      13

     repeater2 uses backplane 2, slot 1-ports 3 & 4, slot 2-port 2
         entLPPhysicalIndex.2.3 ==      3
         entLPPhysicalIndex.2.10 ==     10
         entLPPhysicalIndex.2.11 ==     11
         entLPPhysicalIndex.2.14 ==     14

   Physical to Logical to MIB Alias Mappings -- entAliasMappingTable:
     Repeater Port Identifier values are shared by both repeaters:
         entAliasMappingIdentifier.8.0 ==      rptrPortGroupIndex.1.1
         entAliasMappingIdentifier.9.0 ==      rptrPortGroupIndex.1.2
         entAliasMappingIdentifier.10.0 ==     rptrPortGroupIndex.1.3
         entAliasMappingIdentifier.11.0 ==     rptrPortGroupIndex.1.4
         entAliasMappingIdentifier.13.0 ==     rptrPortGroupIndex.2.1
         entAliasMappingIdentifier.14.0 ==     rptrPortGroupIndex.2.2

   Physical Containment Tree -- entPhysicalContainsTable
     chassis has two backplanes and three containers:
         entPhysicalChildIndex.1.2 ==   2
         entPhysicalChildIndex.1.3 ==   3
         entPhysicalChildIndex.1.4 ==   4
         entPhysicalChildIndex.1.5 ==   5
         entPhysicalChildIndex.1.6 ==   6

     container 1 has a module:
         entPhysicalChildIndex.4.7 ==   7

     container 2 has a module
         entPhysicalChildIndex.5.12 ==  12

    Note that in this example, container 3 is empty.

     module 1 has 4 ports:
         entPhysicalChildIndex.7.8 ==   8
         entPhysicalChildIndex.7.9 ==   9

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         entPhysicalChildIndex.7.10 ==  10
         entPhysicalChildIndex.7.11 ==  11

     module 2 has 2 ports:
         entPhysicalChildIndex.12.13 == 13
         entPhysicalChildIndex.12.14 == 14

4.3.  EMAN Example

   As an example, to illustrate the use of the MIB objects introduced
   with Energy Management (EMAN) applications, consider a router that
   has 16 slots with line cards.  An example of the entPhysicalTable is
   given for 3 components of the router, a chassis, a slot, and a line
   card in that slot.  The chassis contains the slot, and the slot
   contains the line card.

       entPhysicalDescr.1 == 'ACME Series 16 Slots'
       entPhysicalVendorType.1 == acmeProducts.chassisTypes.1
       entPhysicalContainedIn.1 == 0
       entPhysicalClass.1 == chassis(3)
       entPhysicalParentRelPos.1 == -1
       entPhysicalName.1 == 'Router 0 Chassis'
       entPhysicalHardwareRev.1 == ''
       entPhysicalSoftwareRev.1 == ''
       entPhysicalFirmwareRev.1 == ''
       entPhysicalSerialNum.1 == 'abcd1234'
       entPhysicalMfgName.1 == 'ACME'
       entPhysicalModelName.1 == 'ACME-16-LCC'
       entPhysicalAlias.1 == ''
       entPhysicalAssetID.1 == ''
       entPhysicalIsFRU.1 == true(1)
       entPhysicalMfgDate.1 == '2008-7-28,13:30:30.0,-4:0'
       entPhysicalUris.1 == 'urn:f81d4fae-7dec-11d0-a765-00a0c91e6bf6'
       entPhysicalUUID.1 == 'f81d4fae-7dec-11d0-a765-00a0c91e6bf6'

       entPhysicalDescr.2 == 'ACME Line Card Slot'
       entPhysicalVendorType.2 == acmeProducts.slotTypes.1
       entPhysicalContainedIn.2 == 1
       entPhysicalClass.2 = container(5)
       entPhysicalParentRelPos.2 == 6
       entPhysicalName.2 == 'Slot 6'
       entPhysicalHardwareRev.2 == ''
       entPhysicalFirmwareRev.2 == ''
       entPhysicalSoftwareRev.2 == ''
       entPhysicalSerialNum.2 ==   ''
       entPhysicalMfgName.2 ==     'ACME'
       entPhysicalModelName.2 ==   ''

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       entPhysicalAlias.2 ==   ''
       entPhysicalAssetID.2 == ''
       entPhysicalIsFRU.2 == false(2)
       entPhysicalUris.2 == ''urn:7dc53df5-703e-49b3-8670-b1c468f47f1f'
       entPhysicalUUID.2 == '7dc53df5-703e-49b3-8670-b1c468f47f1f'

       entPhysicalDescr.4 == 'ACME Series1 Line Card'
       entPhysicalVendorType.4 == acmeProducts.moduleTypes.14
       entPhysicalContainedIn.4 == 2
       entPhysicalClass.4 == module(9)
       entPhysicalParentRelPos.4 == 0
       entPhysicalName.4 == 'Series1 Linecard'
       entPhysicalHardwareRev.4 == ''
       entPhysicalFirmwareRev.4 == ''
       entPhysicalSoftwareRev.4 == ''
       entPhysicalSerialNum.4 ==   ''
       entPhysicalMfgName.4 == 'ACME'
       entPhysicalModelName.4 == ''
       entPhysicalAlias.4 == ''
       entPhysicalAssetID.4 == ''
       entPhysicalIsFRU.4 == true(1)
       entPhysicalUris.4 ==  'urn:01c47915-4777-11d8-bc70-0090272ff725'
       entPhysicalUUID.4 == '01c47915-4777-11d8-bc70-0090272ff725'

5.  Security Considerations

   There are a number of management objects defined in these MIB modules
   with a MAX-ACCESS clause of read-write and/or read-create.  Such
   objects may be considered sensitive or vulnerable in some network
   environments.  The support for SET operations in a non-secure
   environment without proper protection can have a negative effect on
   network operations.  These are the tables and objects and their
   sensitivity/vulnerability:

      entPhysicalSerialNum
      entPhysicalAlias
      entPhysicalAssetID
      entPhysicalUris

   These objects contain information about the physical entities within
   a managed system, which may be used to identify the serial number,
   identification of assets and managed components, and handling of the
   managed objects.  Their mis-configuration or disclosure may reveal
   sensitive information on assets, perturb the management of entities,
   or cause privacy issues if they allow tracking of values that are
   personally identifying.

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   Some of the readable objects in these MIB modules (i.e., objects with
   a MAX-ACCESS other than not-accessible) may be considered sensitive
   or vulnerable in some network environments.  It is thus important to
   control even GET and/or NOTIFY access to these objects and possibly
   to even encrypt the values of these objects when sending them over
   the network via SNMP.  These are the tables and objects and their
   sensitivity/vulnerability:

      entPhysicalDescr
      entPhysicalVendorType
      entPhysicalHardwareRev
      entPhysicalFirmwareRev
      entPhysicalSoftwareRev
      entPhysicalMfgName
      entPhysicalModelName
      entPhysicalUUID

   These objects expose information about the physical entities within a
   managed system, which may be used to identify the vendor, model,
   version, and specific device-identification information of each
   system component.

      entLogicalDescr
      entLogicalType

   These objects expose the type of logical entities present in the
   managed system.

      entLogicalCommunity

   This object exposes community names associated with particular
   logical entities within the system.

      entLogicalTAddress
      entLogicalTDomain

   These objects expose network addresses that can be used to
   communicate with an SNMP agent on behalf of particular logical
   entities within the system.

      entLogicalContextEngineID
      entLogicalContextName

   These objects identify the authoritative SNMP engine that contains
   information on behalf of particular logical entities within the
   system.

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   SNMP versions prior to SNMPv3 did not include adequate security.
   Even if the network itself is secure (for example by using IPsec),
   there is no control as to who on the secure network is allowed to
   access and GET/SET (read/change/create/delete) the objects in these
   MIB modules.

   Implementations SHOULD provide the security features described by the
   SNMPv3 framework (see [RFC3410]), and implementations claiming
   compliance to the SNMPv3 standard MUST include full support for
   authentication and privacy via the User-based Security Model (USM)
   [RFC3414] with the AES cipher algorithm [RFC3826].  Implementations
   MAY also provide support for the Transport Security Model (TSM)
   [RFC5591] in combination with a secure transport such as SSH
   [RFC5592] or TLS/DTLS [RFC6353].

   Further, deployment of SNMP versions prior to SNMPv3 is NOT
   RECOMMENDED.  Instead, it is RECOMMENDED to deploy SNMPv3 and to
   enable cryptographic security.  It is then a customer/operator
   responsibility to ensure that the SNMP entity giving access to an
   instance of these MIB modules is properly configured to give access
   to the objects only to those principals (users) that have legitimate
   rights to indeed GET or SET (change/create/delete) them.

6.  IANA Considerations

   This document defines the first version of the IANA-maintained
   IANA-ENTITY-MIB module, which allows new physical classes to be added
   to the enumeration in IANAPhysicalClass.  An Expert Review, as
   defined in RFC 5226 [RFC5226], is REQUIRED for each modification.

   The MIB module in this document uses the following IANA-assigned
   OBJECT IDENTIFIER values recorded in the SMI Numbers registry:

              Descriptor        OBJECT IDENTIFIER value
              ----------        -----------------------
              entityMIB          { mib-2 47 }

   IANA has allocated two OBJECT IDENTIFIERS under mib-2 for:

              Descriptor        OBJECT IDENTIFIER value
              ----------        -----------------------
              ianaEntityMIB      { mib-2 216 }
              uuidTCMIB          { mib-2 217 }

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7.  Acknowledgements

   The first three versions of RFCs on the ENTITY MIB modules were
   authored by A. Bierman and K. McCloghrie.  The authors would like to
   thank A. Bierman and K. McCloghrie for the earlier versions of the
   ENTITY MIB.

   The motivation for the extension to RFC 4133 stems from the
   requirements of the EMAN WG of the IETF.

   The authors also thank Juergen Schoenwaelder for his review and
   comments for improving this document.

8.  References

8.1.  Normative References

   [RFC2119]     Bradner, S., "Key words for use in RFCs to Indicate
                 Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RFC2578]     McCloghrie, K., Perkins, D., and J. Schoenwaelder,
                 "Structure of Management Information Version 2
                 (SMIv2)", STD 58, RFC 2578, April 1999.

   [RFC2579]     McCloghrie, K., Ed., Perkins, D., Ed., and J.
                 Schoenwaelder, Ed., "Textual Conventions for SMIv2",
                 STD 58, RFC 2579, April 1999.

   [RFC2580]     McCloghrie, K., Ed., Perkins, D., Ed., and J.
                 Schoenwaelder, Ed., "Conformance Statements for SMIv2",
                 STD 58, RFC 2580, April 1999.

   [RFC3411]     Harrington, D., Presuhn, R., and B. Wijnen, "An
                 Architecture for Describing Simple Network Management
                 Protocol (SNMP) Management Frameworks", STD 62, RFC
                 3411, December 2002.

   [RFC3414]     Blumenthal, U. and B. Wijnen, "User-based Security
                 Model (USM) for version 3 of the Simple Network
                 Management Protocol (SNMPv3)", STD 62, RFC 3414,
                 December 2002.

   [RFC3826]     Blumenthal, U., Maino, F., and K. McCloghrie, "The
                 Advanced Encryption Standard (AES) Cipher Algorithm in
                 the SNMP User-based Security Model", RFC 3826, June
                 2004.

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RFC 6933                 Entity MIB (Version 4)                 May 2013

   [RFC3986]     Berners-Lee, T., Fielding, R., and L. Masinter,
                 "Uniform Resource Identifier (URI): Generic Syntax",
                 STD 66, RFC 3986, January 2005.

   [RFC4122]     Leach, P., Mealling, M., and R. Salz, "A Universally
                 Unique IDentifier (UUID) URN Namespace", RFC 4122, July
                 2005.

   [RFC5226]     Narten, T. and H. Alvestrand, "Guidelines for Writing
                 an IANA Considerations Section in RFCs", BCP 26, RFC
                 5226, May 2008.

   [RFC5591]     Harrington, D. and W. Hardaker, "Transport Security
                 Model for the Simple Network Management Protocol
                 (SNMP)", RFC 5591, June 2009.

   [RFC5592]     Harrington, D., Salowey, J., and W. Hardaker, "Secure
                 Shell Transport Model for the Simple Network Management
                 Protocol (SNMP)", RFC 5592, June 2009.

   [RFC6353]     Hardaker, W., "Transport Layer Security (TLS) Transport
                 Model for the Simple Network Management Protocol
                 (SNMP)", RFC 6353, July 2011.

8.2.  Informative References

   [RFC1157]     Case, J., Fedor, M., Schoffstall, M., and J. Davin,
                 "Simple Network Management Protocol (SNMP)", RFC 1157,
                 May 1990.

   [RFC1516]     McMaster, D. and K. McCloghrie, "Definitions of Managed
                 Objects for IEEE 802.3 Repeater Devices", RFC 1516,
                 September 1993.

   [RFC2108]     de Graaf, K., Romascanu, D., McMaster, D., and K.
                 McCloghrie, "Definitions of Managed Objects for IEEE
                 802.3 Repeater Devices using SMIv2", RFC 2108, February
                 1997.

   [RFC2037]     McCloghrie, K. and A. Bierman, "Entity MIB using
                 SMIv2", RFC 2037, October 1996.

   [RFC2737]     McCloghrie, K. and A. Bierman, "Entity MIB (Version
                 2)", RFC 2737, December 1999.

   [RFC2863]     McCloghrie, K. and F. Kastenholz, "The Interfaces Group
                 MIB", RFC 2863, June 2000.

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RFC 6933                 Entity MIB (Version 4)                 May 2013

   [RFC3406]     Daigle, L., van Gulik, D., Iannella, R., and P.
                 Faltstrom, "Uniform Resource Names (URN) Namespace
                 Definition Mechanisms", BCP 66, RFC 3406, October 2002.

   [RFC3410]     Case, J., Mundy, R., Partain, D., and B. Stewart,
                 "Introduction and Applicability Statements for
                 Internet-Standard Management Framework", RFC 3410,
                 December 2002.

   [RFC4133]     Bierman, A. and K. McCloghrie, "Entity MIB (Version
                 3)", RFC 4133, August 2005.

   [RFC4152]     Tesink, K. and R. Fox, "A Uniform Resource Name (URN)
                 Namespace for the Common Language Equipment Identifier
                 (CLEI) Code", RFC 4152, August 2005.

   [RFC4188]     Norseth, K., Ed., and E. Bell, Ed., "Definitions of
                 Managed Objects for Bridges", RFC 4188, September 2005.

   [T1.213]      ATIS T1.213-2001, "Coded Identification of Equipment
                 Entities in the North American Telecommunications
                 System for Information Exchange", 2001, <www.ansi.org>.

   [T1.213a]     ATIS T1.213a, "Supplement to T1.213-2001, Coded
                 Identification of Equipment Entities in the North
                 American Telecommunications System for Information
                 Exchange, to Correct the Representation of the Basic
                 Code in Figure B.1", 2001, <www.ansi.org>.

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Authors' Addresses

   Andy Bierman
   YumaWorks, Inc.
   274 Redwood Shores Parkway, #133
   Redwood City, CA 94065
   USA

   Phone: +1 408-716-0466
   EMail: [email protected]

   Dan Romascanu
   Avaya
   Park Atidim, Bldg. #3
   Tel Aviv, 61581
   Israel

   Phone: +972-3-6458414
   EMail: [email protected]

   Juergen Quittek
   NEC Europe Ltd.
   Network Research Division
   Kurfuersten-Anlage 36
   Heidelberg  69115
   Germany

   Phone: +49 6221 4342-115
   EMail: [email protected]

   Mouli Chandramouli
   Cisco Systems, Inc.
   Sarjapur Outer Ring Road
   Bangalore 560103
   India

   Phone: +91 80 4429 2409
   EMail: [email protected]

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