Network Working Group K. McCloghrie
Request for Comments: 2737 Cisco Systems, Inc.
Obsoletes: 2037 A. Bierman
Cisco Systems, Inc.
December 1999

Entity MIB (Version 2)

Status of this Memo

This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.

Copyright Notice

Copyright (C) The Internet Society (1999). All Rights Reserved.

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 SNMP
agent.

Table of Contents

1 The SNMP Management Framework ............................... 2
2 Overview .................................................... 3
2.1 Terms ..................................................... 4
2.2 Relationship to Community Strings ......................... 5
2.3 Relationship to SNMP Contexts ............................. 5
2.4 Relationship to Proxy Mechanisms .......................... 6
2.5 Relationship to a Chassis MIB ............................. 6
2.6 Relationship to the Interfaces MIB ........................ 6
2.7 Relationship to the Other MIBs ............................ 7
2.8 Relationship to Naming Scopes ............................. 7
2.9 Multiple Instances of the Entity MIB ...................... 7
2.10 Re-Configuration of Entities ............................. 8
2.11 Textual Convention Change ................................ 8
2.12 MIB StrUCture ............................................ 8
2.12.1 entityPhysical Group ................................... 9
2.12.2 entityLogical Group .................................... 10
2.12.3 entityMapping Group .................................... 10

2.12.4 entityGeneral Group .................................... 11
2.12.5 entityNotifications Group .............................. 11
2.13 Multiple Agents .......................................... 11
2.14 Changes Since RFC2037 ................................... 11
2.14.1 Textual Conventions .................................... 11
2.14.2 New entPhysicalTable Objects ........................... 12
2.14.3 New entLogicalTable Objects ............................ 12
2.14.4 Bugfixes ............................................... 12
3 Definitions ................................................. 13
4 Usage Examples .............................................. 38
4.1 Router/Bridge ............................................. 38
4.2 Repeaters ................................................. 44
5 Intellectual Property ....................................... 51
6 Acknowledgements ............................................ 51
7 References .................................................. 51
8 Security Considerations ..................................... 53
9 Authors' Addresses .......................................... 55
10 Full Copyright Statement ................................... 56

1. The SNMP Management Framework

The SNMP Management Framework presently consists of five major
components:

o An overall architecture, described in RFC2571 [RFC2571].

o Mechanisms for describing and naming objects and events for the
purpose of management. The first version of this Structure of
Management Information (SMI) is called SMIv1 and described in STD
16, RFC1155 [RFC1155], STD 16, RFC1212 [RFC1212] and RFC1215
[RFC1215]. The second version, called SMIv2, is described in STD
58, RFC2578 [RFC2578], STD 58, RFC2579 [RFC2579] and STD 58, RFC
2580 [RFC2580].

o Message protocols for transferring management information. The
first version of the SNMP message protocol is called SNMPv1 and
described in STD 15, RFC1157 [RFC1157]. A second version of the
SNMP message protocol, which is not an Internet standards track
protocol, is called SNMPv2c and described in RFC1901 [RFC1901]
and RFC1906 [RFC1906]. The third version of the message protocol
is called SNMPv3 and described in RFC1906 [RFC1906], RFC2572
[RFC2572] and RFC2574 [RFC2574].

o Protocol operations for Accessing management information. The
first set of protocol operations and associated PDU formats is
described in STD 15, RFC1157 [RFC1157]. A second set of protocol
operations and associated PDU formats is described in RFC1905
[RFC1905].

o A set of fundamental applications described in RFC2573 [RFC2573]
and the view-based access control mechanism described in RFC2575
[RFC2575].

A more detailed introduction to the current SNMP Management Framework
can be found in RFC2570 [RFC2570].

Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB are
defined using the mechanisms defined in the SMI.

This memo specifies a MIB module that is compliant to the SMIv2. A
MIB conforming to the SMIv1 can be produced through the appropriate
translations. The resulting translated MIB must be semantically
equivalent, except where objects or events are omitted because no
translation is possible (use of Counter64). Some machine readable
information in SMIv2 will be converted into textual descriptions in
SMIv1 during the translation process. However, this loss of machine
readable information is not considered to change the semantics of the
MIB.

2. Overview

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

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

- multiple repeaters supported by a single agent;

- multiple OSPF backbone areas, each one 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 fact that it is a single agent in each of these cases implies
there is some relationship which binds all of these entities
together. Effectively, there is some "overall" physical entity which
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 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 what logical entities
are managed by the agent (with some version of SNMP), and thereby to
be able 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 [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 (RFC2571
[RFC2571]). Implementation eXPerience has shown that additional
physical component attributes are also desirable.

2.1. Terms

Some new 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 RFC2571 [RFC2571].

- 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. It is an implementation-specific manner as to which
physical components are represented by an agent in the
EntPhysicalTable. Typically, physical resources (e.g.,
communications ports, backplanes, sensors, daughter-cards, power
supplies, the overall chassis) which can be managed via
functions associated with one or more logical entities are
included in the MIB.

- Containment Tree
Each physical component may be modeled as 'contained' within
another physical component. A "containment-tree" is the
conceptual sequence of entPhysicalIndex values which 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, distinguishing between different logical
entities is one (but not the only) purpose of the community string
(STD 15, RFC1157 [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. An 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.

Note that for community-based versions of SNMP, a network
administrator will likely be able to associate community strings with
naming scopes with 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 this MIB to be a "Chassis MIB replacement", nor is it
within the scope of this MIB to contain all the information which
might be necessary to manage a "chassis". On the other hand, the
entities represented by an implementation of this MIB 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 (RFC
2233 [RFC2233]). Since 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 [RFC2233],
for all types of physical components.

2.7. Relationship to the Other MIBs

The Entity MIB contains a mapping table identifying physical
components that have identifiers from other standard MIBs 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 which are not multi-scoped within a
managed system are likely to ignore context information in
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 (RFC1493 [RFC1493]).

It is an implementation-specific matter as to the isolation of
single-scoped MIB objects by the agent. An agent may wish to limit
the objects returned in a particular naming scope to just 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 exists in a managed system,
and 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 an 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.

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 working group realizes that this change is not strictly supported
by SMIv2. In our judgment, the alternative of deprecating the old
objects and defining new objects would have 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.

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 which 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 is a writable object in
case 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).

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 [RFC2571] method of context identification.

If a 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.

The entLPMappingTable 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.

The entAliasMappingTable contains mappings between entLogicalIndex,
entPhysicalIndex pairs and 'alias' object identifier values. This
allows resources managed with other MIBs (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.

The entPhysicalContainsTable 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, it is also
possible to use it 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 which should be expected for agent implementations.
Therefore, multiple agents within the same managed system are free to
implement the Entity MIB independently. (Refer the section on
"Multiple Instances of the Entity MIB" for more details).

2.14. Changes Since RFC2037

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. The entPhysicalSerialNum
object can be set by a management station in the event the agent
cannot identify this information.

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. Bugfixes

A bug was fixed in the entLogicalCommunity object. The subrange was
incorrect (1..255) and is now (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 which cause an update to the last change
timestamp.

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

3. Definitions

ENTITY-MIB DEFINITIONS ::= BEGIN

IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, mib-2, NOTIFICATION-TYPE
FROM SNMPv2-SMI
TDomain, TAddress, TEXTUAL-CONVENTION,
AutonomousType, RowPointer, TimeStamp, TruthValue
FROM SNMPv2-TC
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF
SnmpAdminString
FROM SNMP-FRAMEWORK-MIB;

entityMIB MODULE-IDENTITY
LAST-UPDATED "9912070000Z" -- December 7, 1999
ORGANIZATION "IETF ENTMIB Working Group"
CONTACT-INFO
" WG E-mail: entmib@cisco.com
Subscribe: majordomo@cisco.com
msg body: subscribe entmib

Keith McCloghrie
ENTMIB Working Group Chair
Cisco Systems Inc.
170 West Tasman Drive
San Jose, CA 95134
+1 408-526-5260
kzm@cisco.com

Andy Bierman
ENTMIB Working Group Editor
Cisco Systems Inc.
170 West Tasman Drive
San Jose, CA 95134
+1 408-527-3711
abierman@cisco.com"
DESCRIPTION
"The MIB module for representing multiple logical
entities supported by a single SNMP agent."
REVISION "9912070000Z"
DESCRIPTION
"Initial Version of Entity MIB (Version 2).
This revision obsoletes RFC2037.
This version published as RFC2737."
REVISION "9610310000Z"
DESCRIPTION

"Initial version (version 1), published as
RFC2037."
::= { mib-2 47 }

entityMIBObjects OBJECT IDENTIFIER ::= { entityMIB 1 }

-- 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
STATUS current
DESCRIPTION
"An arbitrary value which uniquely identifies the physical
entity. The value should be a small positive integer; index
values for different physical entities are not necessarily
contiguous."
SYNTAX INTEGER (1..2147483647)

PhysicalClass ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"An enumerated value which 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, and 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 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
it 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."
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
}

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 RFC
2571 [RFC2571]).

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 not supported)."
SYNTAX OCTET STRING (SIZE(0..32)) -- empty string or SnmpEngineID

-- 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 INTEGER,
entPhysicalClass PhysicalClass,
entPhysicalParentRelPos INTEGER,
entPhysicalName SnmpAdminString,
entPhysicalHardwareRev SnmpAdminString,
entPhysicalFirmwareRev SnmpAdminString,
entPhysicalSoftwareRev SnmpAdminString,
entPhysicalSerialNum SnmpAdminString,
entPhysicalMfgName SnmpAdminString,
entPhysicalModelName SnmpAdminString,
entPhysicalAlias SnmpAdminString,
entPhysicalAssetID SnmpAdminString,
entPhysicalIsFRU TruthValue
}

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 which 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 a 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 }

entPhysicalContainedIn OBJECT-TYPE
SYNTAX INTEGER (0..2147483647)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of entPhysicalIndex for the physical entity which
'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 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 PhysicalClass
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 which most accurately indicates the general class of
the physical entity, or the primary class if there is more
than one.

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 INTEGER (-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 which share the
same instance values of each of the entPhysicalContainedIn
and entPhysicalClass objects.

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).

This value should match any external labeling of the
physical component if possible. 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 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 a
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
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, such as `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 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 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
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 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 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 an 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.

Note that implementations which can correctly identify the
serial numbers of all installed physical entities do not
need to provide write access to the entPhysicalSerialNum
object. Agents which 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 number. 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 which result 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 }

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 an physical entity, the value
of entPhysicalAlias associated with that entity is set to
the zero-length string. However, 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 which result 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
DESCRIPTION
"This object is a user-assigned asset tracking identifier
for the physical entity as specified by a network manager,
and provides non-volatile storage of this information.

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

Not every physical component will have a 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 which result 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 which represent components that are
permanently contained within a field replaceable unit, the
value 'false(2)' should be returned for this object."

::= { entPhysicalEntry 16 }

-- 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
which implement more than one naming scope, at least one
entry must exist. Agents which 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 INTEGER,
entLogicalDescr SnmpAdminString,
entLogicalType AutonomousType,
entLogicalCommunity OCTET STRING,
entLogicalTAddress TAddress,
entLogicalTDomain TDomain,
entLogicalContextEngineID SnmpEngineIdOrNone,
entLogicalContextName SnmpAdminString
}

entLogicalIndex OBJECT-TYPE
SYNTAX INTEGER (1..2147483647)
MAX-ACCESS not-accessible
STATUS current
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 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 which 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 which 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 read-
write community string. However, the agent must take care

not to return a community string which 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 no community string with
suitable access rights can be returned for a particular SNMP
request.

Note that this object is deprecated. Agents which 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 containing the IP-address in network-byte order and
the last 2 containing the UDP port in network-byte order.
Consult 'Transport Mappings for Version 2 of the Simple
Network Management Protocol' (RFC1906 [RFC1906]) for
further information on snmpUDPDomain."

::= { 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 the
Transport Mappings for SNMPv2 document (RFC1906
[RFC1906])."
::= { 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
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 which
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 (since the
entPhysicalContainedIn hierarchy can provide the same
information). If, on the other hand, more than one bridge
was utilizing ports on this module, then mappings between
each bridge and the ports it used would be appropriate.

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
MIBs 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 entity and physical component 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
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 physical equipment, logical
entity to external identifier binding. 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 which 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 INTEGER,
entAliasMappingIdentifier RowPointer
}

entAliasLogicalIndexOrZero OBJECT-TYPE
SYNTAX INTEGER (0..2147483647)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The value of this object identifies the logical entity
which 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 which does not have
an explicit entry in this table for a particular
entPhysicalIndex/entAliasMappingIdentifier pair.

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 any zero-indexed entry. 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.

Since only physical ports are modeled in this table, only
entries which 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
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 which 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."
::= { 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.

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 which implement
version 1 of the Entity MIB."
MODULE -- this module
MANDATORY-GROUPS {

entityPhysicalGroup,
entityLogicalGroup,
entityMappingGroup,
entityGeneralGroup,
entityNotificationsGroup
}
::= { entityCompliances 1 }

entity2Compliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for SNMP entities which 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
which 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 which
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 which
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 which 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
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 which
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 2 }

-- MIB groupings
entityPhysicalGroup OBJECT-GROUP
OBJECTS {
entPhysicalDescr,
entPhysicalVendorType,
entPhysicalContainedIn,
entPhysicalClass,
entPhysicalParentRelPos,
entPhysicalName
}
STATUS current
DESCRIPTION
"The collection of objects which are 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
DESCRIPTION
"The collection of objects which are 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 which are 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 which are 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,
entPhysicalAssetID,
entPhysicalIsFRU
}

STATUS current
DESCRIPTION
"The collection of objects which are 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 which are used to represent the
list of logical entities for which a single SNMP entity
provides management information."
::= { entityGroups 7 }

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

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:

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)

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)

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 == ''
entPhysicalMfgName.3 == 'Acme'
entPhysicalModelName.3 == 'AA'
entPhysicalAlias.3 == ''
entPhysicalAssetID.3 == ''
entPhysicalIsFRU.3 == false(2)

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)

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)

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

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)

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)
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'
entPhysicalModelName.11 == 'FE-100'
entPhysicalAlias.11 == ''
entPhysicalAssetID.11 == ''
entPhysicalIsFRU.11 == false(2)

Logical entities -- entLogicalTable; no SNMPv3 support
2 OSPF instances:
entLogicalDescr.1 == 'Acme OSPF v1.1'
entLogicalType.1 == ospf
entLogicalCommunity.1 == 'public-ospf1'
entLogicalTAddress.1 == 124.125.126.127:161
entLogicalTDomain.1 == snmpUDPDomain
entLogicalContextEngineID.1 == ''
entLogicalContextName.1 == ''

entLogicalDescr.2 == 'Acme OSPF v1.1'
entLogicalType.2 == ospf
entLogicalCommunity.2 == 'public-ospf2'
entLogicalTAddress.2 == 124.125.126.127:161

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 == 124.125.126.127:161
entLogicalTDomain.3 == snmpUDPDomain
entLogicalContextEngineID.3 == ''
entLogicalContextName.3 == ''

entLogicalDescr.4 == 'Acme Bridge v2.1.1'
entLogicalType.4 == dot1dBridge
entLogicalCommunity.4 == 'public-bridge2'
entLogicalTAddress.4 == 124.125.126.127:161
entLogicalTDomain.4 == snmpUDPDomain
entLogicalContextEngineID.4 == ''
entLogicalContextName.4 == ''

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

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

1st bridge group: uses module 1, all ports

[ed. -- Note that these mappings are included in the table since
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
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.9.3 == ifIndex.204
entAliasMappingIdentifier.10.0 == ifIndex.5
entAliasMappingIdentifier.10.3 == ifIndex.205
entAliasMappingIdentifier.11.0 == ifIndex.6
entAliasMappingIdentifier.11.3 == ifIndex.206

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.1.11 == 11

4.2. Repeaters

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 [RFC1516]) rather than the new Repeater MIB (RFC2108
[RFC2108]). The new version contains an object called '

rptrPortRptrId', which should be used to identify repeater port
groupings, rather than with 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'
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'
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'
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 == ''
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'
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 == 124.125.126.127:161
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 == 124.125.126.127:161
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
[ed. -- Note that a mapping to the module is not included,
since in 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
[ed. - in this example, container 3 is empty.]

module 1 has 4 ports:
entPhysicalChildIndex.7.8 == 8
entPhysicalChildIndex.7.9 == 9
entPhysicalChildIndex.7.10 == 10
entPhysicalChildIndex.7.11 == 11

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

5. Intellectual Property

The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.

The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.

6. Acknowledgements

This memo has been produced by the IETF's Entity MIB working group.

7. References

[RFC1155] Rose, M. and K. McCloghrie, "Structure and Identification
of Management Information for TCP/IP-based Internets", STD
16, RFC1155, May 1990.

[RFC1157] Case, J., Fedor, M., Schoffstall, M. and J. Davin, "Simple
Network Management Protocol", STD 15, RFC1157, May 1990.

[RFC1212] Rose, M. and K. McCloghrie, "Concise MIB Definitions", STD
16, RFC1212, March 1991.

[RFC1215] Rose, M., "A Convention for Defining Traps for use with the
SNMP", RFC1215, March 1991.

[RFC1493] Decker, E., Langille, P., Rijsinghani, A. and K.
McCloghrie, "Definitions of Managed Objects for Bridges",
RFC1493, July 1993.

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

[RFC1901] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Introduction to Community-based SNMPv2", RFC1901, January
1996.

[RFC1905] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Protocol Operations for Version 2 of the Simple Network
Management Protocol (SNMPv2)", RFC1905, January 1996.

[RFC1906] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Transport Mappings for Version 2 of the Simple Network
Management Protocol (SNMPv2)", RFC1906, January 1996.

[RFC2026] Bradner, S., "The Internet Standards Process -- Revision
3", BCP 9, RFC2026, October 1996.

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

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

[RFC2233] McCloghrie, K. and F. Kastenholz, "The Interfaces Group MIB
Using SMIv2", RFC2233, November 1997.

[RFC2570] Case, J., Mundy, R., Partain, D. and B. Stewart,
"Introduction to Version 3 of the Internet-standard Network
Management Framework", RFC2570, April 1999.

[RFC2571] Harrington, D., Presuhn, R. and B. Wijnen, "An Architecture
for Describing SNMP Management Frameworks", RFC2571, April
1999.

[RFC2572] Case, J., Harrington D., Presuhn R. and B. Wijnen, "Message
Processing and Dispatching for the Simple Network
Management Protocol (SNMP)", RFC2572, April 1999.

[RFC2573] Levi, D., Meyer, P. and B. Stewart, "SNMPv3 Applications",
RFC2573, April 1999.

[RFC2574] Blumenthal, U. and B. Wijnen, "User-based Security Model
(USM) for version 3 of the Simple Network Management
Protocol (SNMPv3)", RFC2574, April 1999.

[RFC2575] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based
Access Control Model (VACM) for the Simple Network
Management Protocol (SNMP)", RFC2575, April 1999.

[RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M. and S. Waldbusser, "Structure of Management
Information Version 2 (SMIv2)", STD 58, RFC2578, April
1999.

[RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M. and S. Waldbusser, "Textual Conventions for
SMIv2", STD 58, RFC2579, April 1999.

[RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J.,
Rose, M. and S. Waldbusser, "Conformance Statements for
SMIv2", STD 58, RFC2580, April 1999.

8. Security Considerations

There are a number of management objects defined in this MIB that
have 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.

There are a number of managed objects in this MIB that may contain
sensitive information. These are:

entPhysicalDescr
entPhysicalVendorType
entPhysicalHardwareRev
entPhysicalFirmwareRev
entPhysicalSoftwareRev
entPhysicalSerialNum
entPhysicalMfgName
entPhysicalModelName

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

entPhysicalAssetID

This object can allow asset identifiers for various system components
to be exposed, in the event this MIB object is actually configured by
an NMS application.

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 entites 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.

It is thus important to control even GET access to these objects and
possibly to even encrypt the values of these object when sending them
over the network via SNMP. Not all versions of SNMP provide features
for such a secure environment.

SNMPv1 by itself is not a secure environment. Even if the network
itself is secure (for example by using IPSec), even then, 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 this MIB.

It is recommended that the implementers consider the security
features as provided by the SNMPv3 framework. Specifically, the use
of the User-based Security Model RFC2574 [RFC2574] and the View-
based Access Control Model RFC2575 [RFC2575] is recommended.

It is then a customer/user responsibility to ensure that the SNMP
entity giving access to an instance of this MIB, 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.

12. Authors' Addresses

Keith McCloghrie
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134 USA
Phone: +1 408-526-5260
EMail: kzm@cisco.com

Andy Bierman
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134 USA
Phone: +1 408-527-3711
EMail: abierman@cisco.com

9. Full Copyright Statement

Copyright (C) The Internet Society (1999). All Rights Reserved.

This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.

The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.

This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

Funding for the RFCEditor function is currently provided by the
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