The scope of this MIB is targeted for network operators responsible
for managing the operations of network resources. This document
defines an alarm reporting control (ARC) MIB module, which provides a
mechanism for a manager to suppress or defer the reporting of alarm
conditions based on the resource ID and alarm condition type.
For a detailed overview of the documents that describe the current
Internet-Standard Management Framework, please refer to section 7 of
RFC 3410 [RFC3410].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. MIB objects are generally
accessed through the Simple Network Management Protocol (SNMP).
Objects in the MIB are defined using the mechanisms defined in the
Structure of Management Information (SMI). This memo specifies a MIB
module that is compliant to the SMIv2, which is described in STD 58,
RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580
[RFC2580].
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in BCP 14, RFC 2119
[RFC2119].
There is a need to provide a mechanism for controlling the reporting
of alarm conditions of resources in a network device. For example,
(a) inhibiting the reporting of alarm conditions of a resource until
the resource is problem-free, (b) inhibiting the reporting of alarm
conditions of a resource for a specified time period, or (c)
inhibiting the reporting of alarm conditions of a resource
indefinitely until explicitly allowed by the managing system at a
later time.
The alarm reporting control (ARC) feature provides an automatic in-
service provisioning capability. It allows sufficient time for
service setup, customer testing, and other maintenance activities in
an "alarm-free" state. Once a resource is "problem-free", alarm
reporting can be automatically or manually turned on (i.e., allowed).
Lam, et al. Standards Track [Page 2]
RFC 3878 Alarm Reporting Control MIB September 2004
By putting a network resource in ARC mode, (i.e., in nalm, nalmTI,
nalmQI, or nalmQICD states, as described in the MIB), the technicians
and managing systems will not be flooded with unnecessary work items
during operations activities such as service provisioning and network
setup/teardown. This will reduce maintenance costs and improve the
operation and maintenance of these systems. Putting a network
resource in ARC mode shall not affect the availability of active
alarm condition information for potential retrieval.
ITU-T Recommendation M.3100 Amendment 3 [M.3100 Amd3] provides the
business requirements, analysis, and design of the Alarm Reporting
Control feature.
This document defines the MIB objects to support a subset of the ARC
functions described in M.3100 Amd3. In particular, it defines a
table that can be used to specify the ARC settings for the resources
in a system.
Defined in M.3100 Amendment 3 [M.3100 Amd3], there are five ARC
states: alm, nalm, nalmQI, nalmQICD and nalmTI. In the ARC MIB
module, the arcState object is defined to model the M.3100 ARC
states. Note that the state alm (alarm reporting is allowed) is not
listed in the enumeration of the value of this object. However, this
state is implicitly supported by the mib. Once a resource enters the
normal reporting mode (i.e., into the alm state) for the specified
alarm type, the corresponding row will be automatically deleted from
the arc table. Also the manual setting of arcState to alm can be
achieved through setting the RowStatus object to 'destroy'.
The ARC MIB module defined in this document provides a way to control
the reporting of alarm conditions. A set of applicable alarm
conditions is defined in ITU-T Recommendation M.3100 [M.3100] and is
named "probable causes". These probable causes (alarm conditions)
have been included in the IANAItuProbableCause TC, which is defined
in the IANA-ITU-ALARM-TC MIB module [RFC3877]. The IANA-ITU-ALARM-TC
MIB module is maintained in the IANA web-site [ITUALARMTC].
[RFC3877].
The ARC MIB module defines an IANAItuProbableCauseOrZero TC which can
take any value of IANAItuProbableCause or 0. The ARC MIB module
further uses IANAItuProbableCauseOrZero to define the ARC settings
for the managed resource in the network elements. Specification of
objects for defining and storing alarms, including active and history
alarms, standing and transient alarms, and alarm notifications are
out of the scope of this document.
Lam, et al. Standards Track [Page 3]
RFC 3878 Alarm Reporting Control MIB September 2004
When the ARC MIB module is used in a managed system, the following
rules apply:
For alarm condition raised prior to entering ARC mode, reporting of
alarm raised and alarm cleared will be sent as usual.
For alarm condition raised after entering ARC mode and also cleared
before exiting ARC mode, no reporting of alarm raised will be sent
and no reporting of alarm cleared will be sent.
For alarm condition raised after entering ARC mode and not cleared
when exiting ARC mode, the reporting of alarm raised will be deferred
until the moment of exiting ARC mode. The reporting of alarm cleared
will be sent as usual (i.e., at the time of alarm cleared).
Further details of the ARC function can be found in M.3100 Amd3
[M.3100 Amd3].
ARC-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, Unsigned32, mib-2
FROM SNMPv2-SMI -- [RFC2578]
TEXTUAL-CONVENTION, RowStatus, StorageType
FROM SNMPv2-TC -- [RFC2579]
MODULE-COMPLIANCE, OBJECT-GROUP
FROM SNMPv2-CONF -- [RFC2580]
ResourceId
FROM ALARM-MIB; -- [RFC3877]
arcMibModule MODULE-IDENTITY
LAST-UPDATED "200409090000Z" -- September 09, 2004
ORGANIZATION "IETF Distributed Management Working Group"
CONTACT-INFO
"WG EMail: disman@ietf.org
Subscribe: disman-request@ietf.org
http://www.ietf.org/html.charters/disman-charter.html
Chair: Randy Presuhn
E-mail: randy_presuhn@mindspring.com
Editor: Hing-Kam Lam
Lucent Technologies, 4C-616
101 Crawfords Corner Road
Lam, et al. Standards Track [Page 4]
RFC 3878 Alarm Reporting Control MIB September 2004
Holmdel, NJ 07733
USA
Tel: +1 732 949 8338
E-mail: hklam@lucent.com"
DESCRIPTION
"The MIB module describes the objects for controlling a resource
in reporting alarm conditions that it detects.
Copyright (C) The Internet Society (2004). This version
of this MIB module is part of RFC 3878; see the RFC
itself for full legal notices."
REVISION "200409090000Z" -- September 09, 2004
DESCRIPTION
"Initial version, published as RFC 3878."
::={ mib-2 117 }
------------------
-- TEXTUAL-CONVENTION
------------------
IANAItuProbableCauseOrZero ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"This TC can take any value of IANAItuProbableCause or 0.
IANAItuProbableCause is defined in the IANA-ITU-ALARM-TC
module, which is maintained at the IANA web site and
published in the Alarm MIB document (see RFC 3877)."
REFERENCE
"IANA-ITU-ALARM-TC MIB module as maintained at the IANA web site.
The initial module was also published in RFC 3877."
--
SYNTAX INTEGER (0..2147483647)
------------------
-- MIB Objects
------------------
arcTimeIntervals OBJECT IDENTIFIER ::= { arcMibModule 1 }
arcObjects OBJECT IDENTIFIER ::= { arcMibModule 2 }
arcTITimeInterval OBJECT-TYPE
SYNTAX Unsigned32
UNITS "seconds"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
Lam, et al. Standards Track [Page 5]
RFC 3878 Alarm Reporting Control MIB September 2004
"This variable indicates the time interval used for the nalmTI
state, in units of second. It is a pre-defined length of time
in which the resource will stay in the nalmTI state before
transition into the alm state.
Instances of this object SHOULD persist across agent restarts."
::= { arcTimeIntervals 1 }
arcCDTimeInterval OBJECT-TYPE
SYNTAX Unsigned32
UNITS "seconds"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"This variable indicates the time interval used for the nalmQICD
state, in units of second. It is a pre-defined length of time
in which the resource will stay in the nalmQICD state before
transition into the alm state after it is problem-free.
Instances of this object SHOULD persist across agent restarts."
::= { arcTimeIntervals 2 }
arcTable OBJECT-TYPE
SYNTAX SEQUENCE OF ArcEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A table of Alarm Reporting Control (ARC) settings on the system.
Alarm Reporting Control is a feature that provides an automatic
in-service provisioning capability. Alarm reporting is turned
off on a per-resource basis for a selective set of potential
alarm conditions to allow sufficient time for customer testing
and other maintenance activities in an 'alarm free' state.
Once a resource is ready for service, alarm reporting is
automatically or manually turned on.
Functional description and requirements of Alarm Reporting
Control are defined in ITU-T Recommendation M.3100 Amendment 3
[M.3100 Amd3]."
REFERENCE
"ITU Recommendation M.3100 Amendment 3, 'Generic Network
Information Model', January 2001."
::= { arcObjects 1 }
arcEntry OBJECT-TYPE
SYNTAX ArcEntry
Lam, et al. Standards Track [Page 6]
RFC 3878 Alarm Reporting Control MIB September 2004
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A conceptual row that contains information about an ARC setting
of a resource in the system.
Implementation need to be aware that if the total size of
arcIndex and arcNotificationId exceeds 114 sub-IDs, then OIDs
of column instances in this table will have more than 128
sub-IDs and cannot be access using SNMPv1, SNMPv2c, or snmpv3."
INDEX { arcIndex, arcAlarmType, arcNotificationId }
::= { arcTable 1 }
ArcEntry ::=
SEQUENCE {
arcIndex ResourceId,
arcAlarmType IANAItuProbableCauseOrZero,
arcNotificationId OBJECT IDENTIFIER,
arcState INTEGER,
arcNalmTimeRemaining Unsigned32,
arcRowStatus RowStatus,
arcStorageType StorageType
}
arcIndex OBJECT-TYPE
SYNTAX ResourceId
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This object uniquely identifies a resource, which is under the
arcState's control for the associated arcAlarmType.
For example, if the resource is an interface, this object will
point to an instance of interface, e.g., ifIndex.1."
::= { arcEntry 1 }
arcAlarmType OBJECT-TYPE
SYNTAX IANAItuProbableCauseOrZero
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This object identifies the alarm condition type controlled by the
arcState. It specifies the value 0 or a value of
IANAItuProbableCause that is applicable to the resource.
IANAItuProbableCause is defined in the IANA-ITU-ALARM-TC
module in the Alarm MIB document.
Lam, et al. Standards Track [Page 7]
RFC 3878 Alarm Reporting Control MIB September 2004
The value of zero (0) implies any probable causes that are
applicable to the resource. Usually, the applicable probable
causes of a resource are specified in the resource-specific mib."
::= { arcEntry 2 }
arcNotificationId OBJECT-TYPE
SYNTAX OBJECT IDENTIFIER
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This object identifies the type of notification to be suppressed.
The notification type identified should be the one normally used
by the resource for reporting its alarms. When the value of 0.0 is
specified for this object, it implies all applicable notification
types."
::= { arcEntry 3 }
arcState OBJECT-TYPE
SYNTAX INTEGER {
nalm (1),
nalmQI (2),
nalmTI (3),
nalmQICD (4)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Defined in M.3100 Amendment 3 [M.3100 Amd3], there are five
ARC states: alm, nalm, nalmQI, nalmQICD, and nalmTI.
alm: Alarm reporting is turned on (i.e., is allowed).
nalm: Alarm reporting is turned off (i.e., not allowed).
nalmQI: nalm - Qualified Inhibit. Alarm reporting is
turned off until the managed entity is qualified
problem-free for an optional persistence interval.
Problem-free means that the condition corresponding
to the specified alarm type is cleared.
nalmQICD: nalmQI - Count down. This is a substate of nalmQI
and performs the persistence timing countdown
function after the managed entity is qualified
problem-free.
nalmTI: nalm - Timed Inhibit. Alarm reporting is turned
off for a specified time interval.
alm may transition to nalm, nalmQI or nalmTI by management request.
nalm may transition to alm, nalmQI or nalmTI by management request.
Lam, et al. Standards Track [Page 8]
RFC 3878 Alarm Reporting Control MIB September 2004
nalmQI may transition to nalm or alm by management request.
nalmQI may transition to alm automatically
if qualified problem-free (if nalmQICD is not supported) or
if the CD timer expired (if nalmQICD is supported)
nalmTI may transition to alm or nalm by management request.
nalmTI may transition to alm automatically if the TI timer expired.
Further details of ARC state transitions are defined in Figure 3
of M.3100 Amd3 [M.3100 Amd3].
According to the requirements in M.3100 Amd3, a resource
supporting the ARC feature shall support the alm state and at
least one of the nalm, nalmTI, and nalmQI states. The nalmQICD
state is an optional substate of nalmQI.
The arcState object controls the alarm reporting state of a
resource. Note that the state alm (alarm reporting is allowed) is
not listed in the enumeration of the value of this object. However,
this state is implicitly supported by the mib.
Once a resource enters the normal reporting mode (i.e., in the alm
state) for the specified alarm type, the corresponding
row will be automatically deleted from the arc table.
Also the manual setting of arcState to alm can be achieved through
setting the RowStatus object to 'destroy'.
The nalamQICD state is a transitional state from nalmQI to alm. It
is optional depending on the resource type and the implementation
of the resource. If it is supported, before the state
transitions from nalmQI to alm, a count down period is activated
for a duration set by the object arcNalmCDTimeInterval. When the
time is up, the arcState transitions to alm."
::= { arcEntry 4 }
arcNalmTimeRemaining OBJECT-TYPE
SYNTAX Unsigned32
UNITS "seconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This variable indicates the time remaining in the nalmTI state
or the nalmQICD state, in units of second.
At the moment the resource enters the nalmTI state, this variable
will have the initial value equal to the value of
Lam, et al. Standards Track [Page 9]
RFC 3878 Alarm Reporting Control MIB September 2004
arcNalmTITimeInterval and then starts decrementing as time goes by.
Similarly at the moment the resource enters the nalmQICD state,
this variable will have the initial value equal to the value of
arcNalmCDTimeInterval and then starts decrementing as time goes by.
This variable is read-create and thus will allow the manager to
write (extend or shorten), as needed, the remaining time when the
resource is in the nalmTI or nalmQICD state.
If this variable is supported and the resource is currently not in
the nalmTI nor nalmQICD state, the value of this variable shall
equal to zero."
::= { arcEntry 5 }
arcRowStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This columnar object is used for creating and deleting a conceptual
row of the arcTable. It is used to create and delete an arc
setting.
Setting RowStatus to createAndGo or createAndWait implies creating
a new ARC setting for the specified resource and alarm type.
Setting RowStatus to destroy implies removing the ARC setting and
thus has the effect of resuming normal reporting behaviour of the
resource for the alarm type.
Only the objects arcState, arcNalmTimeRemaining, and arcRowStatus
can be updated when a row is active. All the objects, except
arcNalmTimeRemaining, must be set before the row can be activated."
::= { arcEntry 6 }
arcStorageType OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row.
Conceptual rows having the value 'permanent' must
allow write-access at a minimum to arcState.
Note that arcState must allow change by management request.
Therefore, no row can be created with 'readOnly'.
If a set operation tries to set the value to 'readOnly',
then an 'inconsistentValue' error must be returned."
DEFVAL { nonVolatile }
Lam, et al. Standards Track [Page 10]
RFC 3878 Alarm Reporting Control MIB September 2004
::= { arcEntry 7}
--------------------------
-- conformance information
--------------------------
arcConformance OBJECT IDENTIFIER ::= { arcMibModule 3 }
arcCompliances OBJECT IDENTIFIER ::= { arcConformance 1 }
arcCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"The compliance statement for systems supporting
the ARC MIB module."
MODULE -- this module
MANDATORY-GROUPS {
arcSettingGroup
}
OBJECT arcStorageType
WRITE-SYNTAX StorageType {
volatile(2),
nonVolatile(3),
permanent(4)
}
DESCRIPTION
"Support for value 'other' is not required.
The arcState object must allow change by management
request. Therefore, no row can be created with
'readOnly'."
GROUP arcTIGroup
DESCRIPTION
"This group is REQUIRED for ARC settings
that provide the Time Inhibit (TI) function."
GROUP arcQICDGroup
DESCRIPTION
"This group is REQUIRED for ARC settings
that provide the Quality Inhibit (QI) Count Down (CD)
function."
::= { arcCompliances 1 }
arcGroups OBJECT IDENTIFIER ::= { arcConformance 2 }
Lam, et al. Standards Track [Page 11]
RFC 3878 Alarm Reporting Control MIB September 2004
arcSettingGroup OBJECT-GROUP
OBJECTS {
arcState,
arcRowStatus,
arcStorageType
}
STATUS current
DESCRIPTION
"A collection of objects applicable to
basic ARC setting."
::= { arcGroups 1}
arcTIGroup OBJECT-GROUP
OBJECTS {
arcTITimeInterval,
arcNalmTimeRemaining
}
STATUS current
DESCRIPTION
"A collection of objects applicable to
ARC setting that support the Time Inhibit (TI)
function."
::= { arcGroups 2}
arcQICDGroup OBJECT-GROUP
OBJECTS {
arcCDTimeInterval,
arcNalmTimeRemaining
}
STATUS current
DESCRIPTION
"A collection of objects applicable to
ARC setting that support the Quality Inhibit (QI)
Count Down (CD) function."
::= { arcGroups 3}
END
Lam, et al. Standards Track [Page 12]
RFC 3878 Alarm Reporting Control MIB September 2004
There are a number of management objects defined in this MIB module
with a MAX-ACCESS clause of read-write and/or read-create. Such
objects may be considered sensitive or vulnerable in some network
environments. The support for SET operations in a non-secure
environment without proper protection can have a negative effect on
network operations. These are the tables and objects and their
sensitivity/vulnerability:
arcTITimeInterval,
arcCDTimeInterval,
arcState,
arcNalmTimeRemaining,
arcRowStatus,
arcStorageType.
Setting these objects may have disruptive effects on network
operation that range from omission of alarm notifications to flooding
of unwanted alarm notifications from the network. The consequence of
suppressing or deferring the reporting of an alarm can prevent the
timely delivery of important diagnostic information, including
information that can help identify an attack.
Some of the readable objects in this MIB module (i.e., objects with a
MAX-ACCESS other than not-accessible) may be considered sensitive or
vulnerable in some network environments. It is thus important to
control even GET and/or NOTIFY access to these objects and possibly
to even encrypt the values of these objects when sending them over
the network via SNMP. These are the tables and objects and their
sensitivity/vulnerability:
arcTITimeInterval,
arcCDTimeInterval,
arcState,
arcNalmTimeRemaining,
arcRowStatus,
arcStorageType.
Reading these objects will provide information about the setting
which affects alarm notification generation.
SNMP versions prior to SNMPv3 did not include adequate security.
Even if the network itself is secure (for example by using IPSec),
there is no control as to who on the secure network is allowed to
access and GET/SET (read/change/create/delete) the objects in this
MIB module.
Lam, et al. Standards Track [Page 13]
RFC 3878 Alarm Reporting Control MIB September 2004
It is RECOMMENDED that implementers consider the security features as
provided by the SNMPv3 framework (see [RFC3410], section 8),
including full support for the SNMPv3 cryptographic mechanisms (for
authentication and privacy).
Further, deployment of SNMP versions prior to SNMPv3 is NOT
RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to
enable cryptographic security. It is then a customer/operator
responsibility to ensure that the SNMP entity giving access to an
instance of this MIB module 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.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirements Levels", BCP 14, RFC 2119, March 1997.
[RFC2578] McCloghrie, K., Perkins, D., and J. Schoenwaelder,
"Structure of Management Information Version 2
(SMIv2)", STD 58, RFC 2578, April 1999.
[RFC2579] McCloghrie, K., Perkins, D., and J. Schoenwaelder,
"Textual Conventions for SMIv2", STD 58, RFC 2579,
April 1999.
[RFC2580] McCloghrie, K., Perkins, D., and J. Schoenwaelder,
"Conformance Statements for SMIv2", STD 58, RFC 2580,
April 1999.
[RFC3877] Chisholm, S. and D. Romascanu, "Alarm Management
Information Base (MIB)", RFC 3877, September 2004.
[ITUALARMTC] http://www.iana.org/assignments/ianaitualarmtc-mib
[M.3100] ITU Recommendation M.3100, "Generic Network Information
Model", July 1995.
[M.3100 Amd3] ITU Recommendation M.3100 Amendment 3, "Generic Network
Information Model", January 2001.
Lam, et al. Standards Track [Page 14]
RFC 3878 Alarm Reporting Control MIB September 2004
[RFC3410] Case, J., Mundy, R., Partain, D., and B. Stewart,
"Introduction and Applicability Statements for
Internet-Standard Management Framework", RFC 3410,
December 2002.
Copyright (C) The Internet Society (2004). This document is subject
to the rights, licenses and restrictions contained in BCP 78, and
except as set forth therein, the authors retain all their rights.
This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM 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.
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Intellectual Property Rights 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; nor does it represent that it has
made any independent effort to identify any such rights. Information
on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79.
Copies of IPR disclosures made to the IETF Secretariat and any
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attempt made to obtain a general license or permission for the use of
such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at
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The IETF invites any interested party to bring to its attention any
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rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at ietf-
ipr@ietf.org.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
Lam, et al. Standards Track [Page 16]