Remote Monitoring MIB Extensions for

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 (2002). 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 for extending the alarm thresholding capabilities found in the Remote Monitoring (RMON) MIB (RFC 2819), to provide similar threshold monitoring of objects based on the Counter64 data type.

Table of Contents

1 The Internet-Standard Management Framework ................... 2
2 Terms ........................................................ 2
3 Overview ..................................................... 2 3.1 Relationship to the Remote Monitoring MIBs ............... 3
4 MIB Structure ................................................ 4 4.1 MIB Group Overview ....................................... 4

4.1.1 High Capacity Alarm Control Group .................. 5
4.1.2 High Capacity Alarm Capabilities ................... 6
4.1.3 High Capacity Alarm Notifications .................. 6

5 Definitions .................................................. 6
6 Intellectual Property ........................................ 21
7 Acknowledgements ............................................. 21
8 Normative References ......................................... 21
9 Informative References ....................................... 22

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10 Security Considerations ..................................... 22 11 Authors' Addresses .......................................... 23 12 Full Copyright Statement .................................... 24

1. The Internet-Standard Management Framework

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

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

2. Terms

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14, RFC 2119. [RFC2119]

3. Overview

There is a need for a standardized way of providing the same type of alarm thresholding capabilities for Counter64 objects, as already exists for Counter32 objects. The RMON-1 alarmTable objects and RMON-1 notification types are specific to 32-bit objects, and cannot be used to properly monitor Counter64-based objects. Extensions to these existing constructs which explicitly support Counter64-based objects are needed. These extensions are completely independent of the existing RMON-1 alarm mechanisms.

The usage of Counter64 objects is increasing. One of the causes for this increase is the increasing speeds of network interfaces; RFC 2863 [RFC2863] says:

As the speed of network media increase, the minimum time in which a 32 bit counter will wrap decreases. For example, a 10Mbs stream of back-to-back, full-size packets causes ifInOctets to wrap in just over 57 minutes; at 100Mbs, the minimum wrap time is 5.7 minutes, and at 1Gbs, the minimum is 34 seconds. Requiring that interfaces be polled frequently enough not to miss a counter wrap is increasingly problematic.

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and therefore requires:

For interfaces that operate at 20,000,000 (20 million) bits per second or less, 32-bit byte and packet counters MUST be supported. For interfaces that operate faster than 20,000,000 bits/second, and slower than 650,000,000 bits/second, 32-bit packet counters MUST be supported and 64-bit octet counters MUST be supported. For interfaces that operate at 650,000,000 bits/second or faster, 64-bit packet counters AND 64-bit octet counters MUST be supported.

Of the variables on which thresholds are set using RMON-1's alarmTable, two of the most popular are: ifInOctets and ifOutOctets. Thus, the increasing usage of the 64-bit versions: ifHCInOctets and ifHCOutOctets means that there is an increasing requirement to use RMON-1's thresholding capability for ifHCInOctets and ifHCOutOctets.

The RMON-1 Alarm Group is implemented not only by all RMON probes, but also by the SNMP agents in many other types of devices for the purpose of monitoring any of their (non-RMON) integer-valued MIB objects. The fact that it has been so widely implemented indicates its obvious value. Without this extension, that obvious value is becoming incomplete because of its lack of support for 64-bit integers. This extension is the easiest, simplest, and most compatible way for an implementation to overcome that lack of support.

3.1. Relationship to the Remote Monitoring MIBs

This MIB is intended to be implemented in Remote Monitoring (RMON) probes, which may also support the RMON-1 MIB [RFC2819]. Such probes may be stand-alone devices, or may be co-located with other networking devices (e.g., ethernet switches and repeaters).

The functionality of the High Capacity Alarm Group is a superset of RMON-1's Alarm Group. Thus, one day in the distant future, it is a possibility that RMON-1's Alarm Group will be deprecated in favor of this MIB's High Capacity Alarm Group. However, that day will not come before this document, or one of its successors, reaches the same standardization state as RMON-1.

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4. MIB Structure

Figure 1: HC-ALARM MIB Functional Structure

    +---------------------------------------------+
    |                                             |
    |     (RMON-1)              (HC-ALARM)        |
    |   +-----------+          +-----------+      |
    |   |           |          |           |      |
    |   |   alarm   |          |  hcAlarm  |      |
    |   |   Table   |          |  Table    |      |
    |   |           |          |           |      |
    |   +-----------+          +-----------+      |
    |         |                      |            |
    |         V      (RMON-1)        V            |
    |   +----------------------------------+      |
    |   |                                  |      |
    |   |            eventTable            |      |
    |   |                                  |      |
    |   +----------------------------------+      |
    |         |                      |            |
    |         |                      |            |
    |         V                      V            |
    |   +---------------+    +----------------+   |
    |   | risingAlarm   |    | hcRisingAlarm  |   |
    |   | fallingAlarm  |    | hcFallingAlarm |   |
    |   | Notifications |    | Notifications  |   |
    |   +---------------+    +----------------+   |
    |       (RMON-1)             (HC-ALARM)       |
    +---------------------------------------------+

4.1. MIB Group Overview

The HC-ALARM MIB contains three MIB groups:

• hcAlarmControlObjects group Controls the configuration of alarms for high capacity MIB object instances.
  
  
• hcAlarmCapabilities group Describes the high capacity alarm capabilities provided by the agent.
  
  
• hcAlarmNotifications group Provide new rising and falling threshold notifications for high capacity objects.
  
  
  
  

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4.1.1. High Capacity Alarm Control Group

This group contains one table, which is used by a management station to configure high capacity alarm entries. To configure alarm thresholding for Counter64 or CounterBasedGauge64 objects, a management application must configure the hcAlarmTable in a manner similar to how RMON-1's alarmTable is configured.

Because the language in some of the DESCRIPTION clauses of objects in the alarmTable is specific to the alarmTable itself, their defined semantics do not allow them to be used for this MIB also. Therefore, the following objects are essentially cloned from the alarmTable to the hcAlarmTable:

alarmTable	hcAlarmTable
alarmIndex	hcAlarmIndex
alarmInterval	hcAlarmInterval
alarmVariable	hcAlarmVariable
alarmSampleType	hcAlarmSampleType
alarmStartupAlarm	hcAlarmStartupAlarm
alarmRisingEventIndex	hcAlarmRisingEventIndex
alarmFallingEventIndex	hcAlarmFallingEventIndex
alarmOwner	hcAlarmOwner
alarmStatus	hcAlarmStatus

In addition, the following hcAlarmTable objects are used as high capacity values instead of the corresponding 32-bit version in the alarmTable.

alarmTable	hcAlarmTable
alarmValue	hcAlarmAbsValue hcAlarmValueStatus
alarmRisingThreshold	hcAlarmRisingThreshAbsValueLo hcAlarmRisingThreshAbsValueHi hcAlarmRisingThresholdValStatus
alarmFallingThreshold	hcAlarmFallingThreshAbsValueLo hcAlarmFallingThreshAbsValueHi hcAlarmFallingThresholdValStatus

Nevertheless, the hcAlarmTable does have a few differences from the alarmTable:

• Counter64 based objects are thresholded properly
• an entry is not destroyed if the instance identified by the hcAlarmVariable is not available during a polling interval.
  
  
  

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• the RowStatus textual convention is used instead of EntryStatus for the hcAlarmStatus object.
• the non-volatile storage of an HC alarm entry is explicitly controlled with a StorageType parameter.
• a counter is provided to indicate the number of times the hcAlarmVariable object value could not be retrieved by the agent.

4.1.2. High Capacity Alarm Capabilities

This group contains a single scalar object, called hcAlarmCapabilities. It describes the basic high capacity alarm features supported by the agent.

4.1.3. High Capacity Alarm Notifications

This group contains two notifications, hcRisingAlarm and hcFallingAlarm. These are generated for high capacity alarms in the same manner and used to convey essentially the same information as RMON-1's risingAlarm and fallingAlarm notifications do for alarmTable-specified alarms.

5. Definitions

HC-ALARM-MIB DEFINITIONS ::= BEGIN

IMPORTS

MODULE-IDENTITY, OBJECT-TYPE, NOTIFICATION-TYPE, Integer32, Counter32, Unsigned32 FROM SNMPv2-SMI
MODULE-COMPLIANCE, OBJECT-GROUP, NOTIFICATION-GROUP
FROM SNMPv2-CONF
RowStatus, VariablePointer, StorageType, TEXTUAL-CONVENTION
FROM SNMPv2-TC
CounterBasedGauge64
FROM HCNUM-TC
rmon, OwnerString, rmonEventGroup FROM RMON-MIB;

hcAlarmMIB MODULE-IDENTITY

LAST-UPDATED	"200212160000Z"
ORGANIZATION CONTACT-INFO	"IETF RMONMIB Working Group"
"	Andy Bierman Cisco Systems, Inc.
Tel: +1 408 527-3711

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E-mail: abierman@cisco.com

Postal:

170 West Tasman Drive San Jose, CA USA 95134

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

Send comments to <rmonmib@ietf.org> Mailing list subscription info: http://www.ietf.org/mailman/listinfo/rmonmib " DESCRIPTION
"This module defines Remote Monitoring MIB extensions for High Capacity Alarms.

Copyright (C) The Internet Society (2002). This version of this MIB module is part of RFC 3434; see the RFC itself for full legal notices."

hcAlarmControlObjects OBJECT IDENTIFIER

:= { hcAlarmObjects 1 } hcAlarmCapabilitiesObjects OBJECT IDENTIFIER

                                        ::= { hcAlarmObjects 2 }

--
-- Textual Conventions
--

HcValueStatus

:= TEXTUAL-CONVENTION
STATUS current DESCRIPTION "This data type indicates the validity and sign of the data in associated object instances which represent the absolute value of a high capacity numeric quantity. Such an object may be represented with one or more object instances. An object of type HcValueStatus MUST be defined within the same

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structure as the object(s) representing the high capacity absolute value.

If the associated object instance(s) representing the high capacity absolute value could not be accessed during the sampling interval, and is therefore invalid, then the associated HcValueStatus object will contain the value 'valueNotAvailable(1)'.

If the associated object instance(s) representing the high capacity absolute value are valid and actual value of the sample is greater than or equal to zero, then the associated HcValueStatus object will contain the value 'valuePositive(2)'.

	If the associated object instance(s) representing the high capacity absolute value are valid and the actual value of the sample is less than zero, then the associated HcValueStatus object will contain the value 'valueNegative(3)'. The associated absolute value should be multiplied by -1 to obtain the true sample value."
SYNTAX INTEGER {
}	valueNotAvailable(1), valuePositive(2), valueNegative(3)

--
-- High Capacity Alarm Table
--

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Because SNMP access control is articulated entirely in terms of the contents of MIB views, no access control mechanism exists that can restrict the value of this object to identify only those objects that exist in a particular MIB view. Because there is thus no acceptable means of restricting the read access that could be obtained through the alarm mechanism, the probe must only grant write access to this object in those views that have read access to all objects on the probe.

If the associated hcAlarmVariable instance could not be obtained at the previous sample interval, then a delta

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sample is not possible, and the value of the associated hcAlarmValueStatus object for this interval will be valueNotAvailable(1).

To obtain the true value for this sampling interval, the associated instance of hcAlarmValueStatus must be checked, and the value of this object adjusted as necessary.

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active. If the first sample after this entry becomes active is greater than or equal to the rising threshold and this object is equal to risingAlarm(1) or risingOrFallingAlarm(3), then a single rising alarm will be generated. If the first sample after this entry becomes valid is less than or equal to the falling threshold and this object is equal to fallingAlarm(2) or risingOrFallingAlarm(3), then a single falling alarm will be generated.

ABS(threshold)

hcAlarmRisingThreshAbsValueLo + (hcAlarmRisingThreshAbsValueHi * 2^^32)

The absolute value of the threshold is adjusted as required, as described in the HcValueStatus textual convention. These three object instances are conceptually combined to represent the rising threshold for this entry.

When the current sampled value is greater than or equal to this threshold, and the value at the last sampling interval was less than this threshold, a single event will be generated. A single event will also be generated if the first sample after this entry becomes valid is greater than or equal to this threshold and the associated hcAlarmStartupAlarm is equal to risingAlarm(1) or risingOrFallingAlarm(3).

After a rising event is generated, another such event will not be generated until the sampled value falls below this threshold and reaches the threshold identified by the hcAlarmFallingThreshAbsValueLo, hcAlarmFallingThreshAbsValueHi, and hcAlarmFallingThresholdValStatus objects.

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This object may not be modified if the associated hcAlarmStatus object is equal to active(1)."

::= { hcAlarmEntry 8 }

ABS(threshold)

hcAlarmRisingThreshAbsValueLo + (hcAlarmRisingThreshAbsValueHi * 2^^32)

The absolute value of the threshold is adjusted as required, as described in the HcValueStatus textual convention. These three object instances are conceptually combined to represent the rising threshold for this entry.

When the current sampled value is greater than or equal to this threshold, and the value at the last sampling interval was less than this threshold, a single event will be generated. A single event will also be generated if the first sample after this entry becomes valid is greater than or equal to this threshold and the associated hcAlarmStartupAlarm is equal to risingAlarm(1) or risingOrFallingAlarm(3).

After a rising event is generated, another such event will not be generated until the sampled value falls below this threshold and reaches the threshold identified by the hcAlarmFallingThreshAbsValueLo, hcAlarmFallingThreshAbsValueHi, and hcAlarmFallingThresholdValStatus objects.

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DESCRIPTION
"This object indicates the sign of the data for the rising threshold, as defined by the hcAlarmRisingThresAbsValueLo and hcAlarmRisingThresAbsValueHi objects, as described in the HcValueStatus textual convention.

The enumeration 'valueNotAvailable(1)' is not allowed, and the associated hcAlarmStatus object cannot be equal to 'active(1)' if this object is set to this value.

ABS(threshold)

hcAlarmFallingThreshAbsValueLo + (hcAlarmFallingThreshAbsValueHi * 2^^32)

The absolute value of the threshold is adjusted as required, as described in the HcValueStatus textual convention. These three object instances are conceptually combined to represent the falling threshold for this entry.

When the current sampled value is less than or equal to this threshold, and the value at the last sampling interval was greater than this threshold, a single event will be generated. A single event will also be generated if the first sample after this entry becomes valid is less than or equal to this threshold and the associated hcAlarmStartupAlarm is equal to fallingAlarm(2) or risingOrFallingAlarm(3).

After a falling event is generated, another such event will not be generated until the sampled value rises above this threshold and reaches the threshold identified by the hcAlarmRisingThreshAbsValueLo, hcAlarmRisingThreshAbsValueHi, and hcAlarmRisingThresholdValStatus objects.

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ABS(threshold)

hcAlarmFallingThreshAbsValueLo + (hcAlarmFallingThreshAbsValueHi * 2^^32)

The absolute value of the threshold is adjusted as required, as described in the HcValueStatus textual convention. These three object instances are conceptually combined to represent the falling threshold for this entry.

When the current sampled value is less than or equal to this threshold, and the value at the last sampling interval was greater than this threshold, a single event will be generated. A single event will also be generated if the first sample after this entry becomes valid is less than or equal to this threshold and the associated hcAlarmStartupAlarm is equal to fallingAlarm(2) or risingOrFallingAlarm(3).

After a falling event is generated, another such event will not be generated until the sampled value rises above this threshold and reaches the threshold identified by the hcAlarmRisingThreshAbsValueLo, hcAlarmRisingThreshAbsValueHi, and hcAlarmRisingThresholdValStatus objects.

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"This object indicates the sign of the data for the falling threshold, as defined by the hcAlarmFallingThreshAbsValueLo and hcAlarmFallingThreshAbsValueHi objects, as described in the HcValueStatus textual convention.

The enumeration 'valueNotAvailable(1)' is not allowed, and the associated hcAlarmStatus object cannot be equal to 'active(1)' if this object is set to this value.

hcAlarmValueFailedAttempts OBJECT-TYPE

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SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION

	"The number of times the associated hcAlarmVariable instance was polled on behalf of this hcAlarmEntry, (while in the active state) and the value was not available. This counter may experience a discontinuity if the agent restarts, indicated by the value of sysUpTime."
::= {	hcAlarmEntry 16 }

hcAlarmOwner OBJECT-TYPE

SYNTAX OwnerString
MAX-ACCESS read-create
STATUS current
DESCRIPTION

	"The entity that configured this entry and is therefore using the resources assigned to it."
::= {	hcAlarmEntry 17 }

hcAlarmStorageType OBJECT-TYPE

SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION

An entry MUST NOT exist in the active state unless all objects in the entry have an appropriate value, as described in the description clause for each writable object.

	The hcAlarmStatus object may be modified if the associated instance of this object is equal to active(1), notInService(2), or notReady(3). All other writable objects may be modified if the associated instance of this object is equal to notInService(2) or notReady(3)."
::= {	hcAlarmEntry 19 }

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--
-- Capabilities
--

If the 'hcAlarmCreation' BIT is set, then this agent allows NMS applications to create entries in the hcAlarmTable.

	If the 'hcAlarmNvStorage' BIT is	set, then this agent allows
	entries in the hcAlarmTable which will be recreated after a
	system restart, as controlled by object."	the hcAlarmStorageType
::= {	hcAlarmCapabilitiesObjects 1 }

--
-- Notifications
--

hcAlarmNotifPrefix OBJECT IDENTIFIER
::= { hcAlarmNotifications 0 }

hcRisingAlarm NOTIFICATION-TYPE

OBJECTS { hcAlarmVariable,

	hcAlarmSampleType, hcAlarmAbsValue, hcAlarmValueStatus, hcAlarmRisingThreshAbsValueLo, hcAlarmRisingThreshAbsValueHi, hcAlarmRisingThresholdValStatus, hcAlarmRisingEventIndex }
STATUS	current
DESCRIPTION
	"The SNMP notification that is generated when a high capacity alarm entry crosses its rising threshold and generates an event that is configured for sending SNMP traps.

The hcAlarmEntry object instances identified in the OBJECTS

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	clause are from the entry that causes this notification to be generated."
::= {	hcAlarmNotifPrefix 1 }

hcFallingAlarm NOTIFICATION-TYPE

OBJECTS { hcAlarmVariable,

	hcAlarmSampleType, hcAlarmAbsValue, hcAlarmValueStatus, hcAlarmFallingThreshAbsValueLo, hcAlarmFallingThreshAbsValueHi, hcAlarmFallingThresholdValStatus, hcAlarmFallingEventIndex }
STATUS	current
DESCRIPTION
	"The SNMP notification that is generated when a high capacity alarm entry crosses its falling threshold and generates an event that is configured for sending SNMP traps.
	The hcAlarmEntry object instances identified in the OBJECTS clause are from the entry that causes this notification to be generated."
::= {	hcAlarmNotifPrefix 2 }

--
-- Conformance Section
--

hcAlarmCompliances OBJECT IDENTIFIER ::= { hcAlarmConformance 1 }
hcAlarmGroups      OBJECT IDENTIFIER ::= { hcAlarmConformance 2 }

hcAlarmCompliance MODULE-COMPLIANCE

STATUS current
DESCRIPTION
"Describes the requirements for conformance to the High Capacity Alarm MIB."

MODULE -- this module
MANDATORY-GROUPS	{	hcAlarmControlGroup, hcAlarmCapabilitiesGroup, hcAlarmNotificationsGroup
MODULE RMON-MIB
MANDATORY-GROUPS	{	rmonEventGroup }

::= { hcAlarmCompliances 1 }

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-- Object Groups

"A collection of notifications to deliver information related to a high capacity rising or falling threshold event

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to a management application."
::= { hcAlarmGroups 3 }

END

6. 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.

7. Acknowledgements

This memo is a product of the RMONMIB working group, and is based on existing alarmTable objects in the RMON-1 MIB module [RFC2819]. In order to maintain the RMON 'look-and-feel' and semantic consistency, some of Steve Waldbusser's text from [RFC2819] has been adapted for use in this MIB.

8. Normative References

[RFC2026]

Bradner, S., "The Internet Standards Process -- Revision 3", BCP 9, RFC 2026, October 1996.

[RFC2119]

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

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[RFC2578]

McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.

[RFC2579]

McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999.

[RFC2580]

McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Conformance Statements for SMIv2", RFC 2580, STD 58, April 1999.

[RFC2819]

Waldbusser, S., "Remote Network Monitoring Management Information Base", STD 59, RFC 2819, May 2000.

[RFC3414]

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

[RFC3415]

Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", STD 62, RFC 3415, December 2002.

9. Informative References

[RFC3410]

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

[RFC2863]

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

10. 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:

hcAlarmAbsValue
hcAlarmValueStatus

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These objects are used together, and may expose the values of particular MIB instances, as identified by associated instances of the hcAlarmVariable object.

hcAlarmVariable

This object identifies the object instance that the associated hcAlarmEntry will periodically sample. Because SNMP access control is articulated entirely in terms of the contents of MIB views, no access control mechanism exists that can restrict the value of this object to identify only those objects that exist in a particular MIB view. Thus, because there is no acceptable means of restricting the read access that could be obtained through the alarm mechanism, the probe must only grant write access to this object in those views that have read access to all objects on the probe.

SNMPv1 by itself is not a secure environment. Even if the network itself is secure (for example by using IPSec), there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB.

It is recommended that the implementors consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model STD 62, RFC 3414 [RFC3414] and the View-based Access Control Model STD 62, RFC 3415 [RFC3415] 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 only the objects, and to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them.

11. Authors' Addresses

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

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

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12. Full Copyright Statement

Copyright (C) The Internet Society (2002). All Rights Reserved.

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