Internet Engineering Task Force (IETF) P. Aitken, Ed.
Request for Comments: 8038 Brocade
Category: Standards Track B. Claise
ISSN: 2070-1721 Cisco Systems, Inc.
S. B S
Mojo Networks, Inc.
C. McDowall
Brocade
J. Schoenwaelder
Jacobs University Bremen
May 2017
Exporting MIB Variables
Using the IP Flow Information Export (IPFIX) Protocol
Abstract
This document specifies a way to complement IP Flow Information
Export (IPFIX) Data Records with Management Information Base (MIB)
objects, avoiding the need to define new IPFIX Information Elements
for existing MIB objects that are already fully specified.
Two IPFIX Options Templates, as well as a method for creating IPFIX
Options Templates that are used to export the extra data required to
fully describe Simple Network Management Protocol (SNMP) MIB objects
in IPFIX, are specified herein.
Status of This Memo
This is an Internet Standards Track document.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
Internet Standards is available in Section 2 of RFC 7841.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc8038.
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Copyright Notice
Copyright (c) 2017 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction ....................................................4
2. Motivation ......................................................5
3. Terminology .....................................................7
4. High-Level Solution Overview ....................................8
5. MIB Object Value Information Elements and the MIB Field
Options Template ...............................................10
5.1. MIB Field Options Architecture ............................11
5.2. IPFIX and MIB Data Model ..................................13
5.3. MIB Field Options - Specifications and Required Fields ....15
5.3.1. MIB Field Options Template .........................16
5.3.2. MIB Type Options Template ..........................16
5.4. MIB Field Options Template Formats ........................17
5.4.1. Data Template Containing a mibObjectValue Field ....17
5.4.2. MIB Field Options Template .........................19
5.4.3. MIB Field Options Data Records .....................20
5.4.4. Options Template Containing a
mibObjectValue Field ...............................21
5.4.5. MIB Field Options Template with Semantics Fields ...23
5.4.6. MIB Field Options Template with Extra MIB
Object Details .....................................24
5.5. Use of Field Order in the MIB Field Options Template ......27
5.6. Identifying the SNMP Context ..............................27
5.7. Template Management .......................................28
5.7.1. Large Messages .....................................28
5.7.2. Template Withdrawal and Reuse ......................29
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5.8. Exporting Conceptual Rows and Tables ......................29
5.8.1. Exporting Conceptual Rows - Indexing ...............30
5.8.2. Exporting Conceptual Rows - mibObjectValueRow ......30
5.8.3. Exporting Conceptual Rows - AUGMENTS ...............36
5.8.4. Exporting Conceptual Tables - mibObjectValueTable ..37
5.8.5. Exporting Columnar Objects: Using
mibIndexIndicator ..................................38
6. Example Use Cases ..............................................39
6.1. Non-columnar MIB Object: Established TCP Connections ......39
6.2. Enterprise-Specific MIB Object: Detailing CPU Load
History ...................................................42
6.3. Exporting a Conceptual Row: The OSPF Neighbor Row .........45
6.4. Exporting Augmented Conceptual Row: Mapping IF-MIB
ID to Name ................................................49
6.5. Exporting a Columnar Object: ipIfStatsInForwDatagrams .....55
6.6. Exporting a Columnar Object Indexed by Information
Elements: ifOutQLen .......................................58
6.7. Exporting with Multiple Contexts: The OSPF
Neighbor Row Revisited ....................................62
7. Configuration Considerations ...................................65
8. The Collecting Process's Side ..................................66
9. Applicability ..................................................66
10. Security Considerations .......................................67
11. IANA Considerations ...........................................68
11.1. New IPFIX Semantics ......................................68
11.1.1. snmpCounter .......................................68
11.1.2. snmpGauge .........................................68
11.2. New IPFIX Information Elements ...........................69
11.2.1. New MIB Object Value Information Elements .........69
11.2.2. New MIB Field Options Information Elements ........75
11.2.3. New MIB Type Information Elements .................79
12. References ....................................................81
12.1. Normative References .....................................81
12.2. Informative References ...................................82
Acknowledgments ...................................................84
Authors' Addresses ................................................84
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1. Introduction
There is growing interest in using IP Flow Information Export (IPFIX)
as a push mechanism for exporting management information. Using a
push protocol such as IPFIX instead of a polling protocol like SNMP
is especially interesting in situations where large chunks of
repetitive data need to be exported periodically.
While initially targeted at different problems, there is a large
parallel between the information transported via IPFIX and SNMP.
Furthermore, certain Management Information Base (MIB) objects are
highly relevant to Flows as they are understood today. For example,
in the IPFIX Information Model [IANA-IPFIX], Information Elements
coming from the SNMP world have already been specified, e.g.,
ingressInterface and egressInterface both refer to the ifIndex object
as defined in [RFC2863].
In particular, the Management Information Base was designed as a
separate system of definitions; this opens up the possibility of
exporting objects defined via the MIB over other protocols.
Rather than mapping existing MIB objects to IPFIX Information
Elements on a case-by-case basis, it would be advantageous to enable
the export of any existing or future MIB objects as part of an IPFIX
Data Record. This way, the duplication of Data Models [RFC3444],
both as SMIv2 MIB objects and IPFIX Information Elements, out of the
same Information Model [RFC3444] would be avoided.
Therefore, the primary goals of this document are:
o to specify a way to complement IPFIX Data Records with MIB
objects;
o to avoid the need to define new IPFIX Information Elements for
existing MIB objects that are already fully specified;
o to allow the correlation of SNMP and IPFIX sourced data by
exporting them together; and
o to allow SNMP push data from SNMP-only devices to be more easily
integrated into IPFIX-based collection infrastructures.
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2. Motivation
The intended scope of this work is the addition of MIB variable(s) to
IPFIX Information Elements in Data Records, in order to complement
the Data Records with useful and already-standardized information.
Special consideration is given to the case of an existing
Template Record that needs to be augmented with some MIB variables
whose index is already present in the Template Record as an IPFIX
Information Element -- for example, a 7-tuple Data Record containing
the ingressInterface Information Element, which needs to be augmented
by interface counters [RFC2863] that are indexed by the respective
ingressInterface values already contained in the Data Records. See
Section 3 for terminology definitions.
Many Data Records contain the ingressInterface and/or the
egressInterface Information Elements. These Information Elements
carry an ifIndex value, a MIB object defined in [RFC2863]. In order
to retrieve additional information about the identified interface, a
Collector could simply poll relevant objects from the device running
the Exporter via SNMP. However, that approach has several problems:
o It requires implementing a mediation function between two Data
Models, i.e., MIB objects and IPFIX Information Elements.
o Confirming the validity of simple mappings (e.g., ifIndex to
ifName) requires either checking on a regular basis that the
Exporter's network management system did not reload or imposing
ifIndex persistence across an Exporter's reload.
o Synchronization problems occur because counters carried in
Data Records and counters carried in SNMP messages are retrieved
from the Exporter at different points in time and thus cannot be
correlated. In the best case, assuming very tight integration of
an IPFIX Collector with an SNMP polling engine, SNMP data is
retrieved shortly after Data Records have been received, which
implies a delay of the sum of the active or idle timeouts (if not
null) plus the time to export the Data Record to the Collector.
If, however, the SNMP data is retrieved by a generic Network
Management Station (NMS) polling interface statistics, then the
time lag between IPFIX counters and SNMP counters can be
significantly higher. See [RFC5102] for details regarding active
and idle timeouts.
This document does not specify how to carry SNMP notifications in
IPFIX, even if the specifications in this document could potentially
allow this.
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Since IPFIX is a push mechanism, initiated from the Exporter with no
acknowledgment method, this specification does not provide the
ability to execute configuration changes.
The Distributed Management Expression MIB [RFC2982], which is a
mechanism to create new MIB variables based on the content of
existing ones, could also be advantageous in the context of this
specification. Indeed, newly created MIB objects (for example, the
link utilization MIB variable), created with the Distributed
Management Expression MIB [RFC2982], could nicely complement
Data Records.
Another advantage of exporting MIB objects via IPFIX is that IPFIX
would benefit from an extended series of types to be exported. The
simple and application-wide data types specified in SMIv2 [RFC2578],
along with new textual conventions, can be exported within IPFIX and
then decoded in the Collector. However, since a textual convention
can contain almost any name, this document does not extend the
existing "IPFIX Information Elements" subregistry [IANA-IPFIX] that
contains informationElementDataType.
The overall architectural model is depicted in Figure 1. The IPFIX
Exporter accesses the device's instrumentation, which follows the
specifications contained in MIB modules. Other management
interfaces, such as the Network Configuration Protocol (NETCONF) or
the device's Command Line Interface (CLI), may provide access to the
same instrumentation.
+------+ +-------+ +.........+ +.....+
| SNMP | | IPFIX | : NETCONF : : CLI :
+------+ +-------+ +.........+ +.....+
| | | |
+--------------------------------------------+
| Instrumentation (specified in MIB modules) |
+--------------------------------------------+
Figure 1: Architectural Model
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3. Terminology
IPFIX-specific terminology (Information Element, Template,
Template Record, Options Template Record, Template Set, Collector,
Exporter, Data Record, Transport Session, Exporting Process,
Collecting Process, etc.) used in this document is defined in
Section 2 of [RFC7011]. As in [RFC7011], these IPFIX-specific terms
have the first letter of a word capitalized.
This document prefers the more generic term "Data Record" (as opposed
to "Flow Record") in relation to the export of MIB objects.
Object Identifier (MIB OID)
An Object Identifier value is an ordered list of non-negative
numbers. For SMIv2, each number in the list is referred to as a
sub-identifier. There are at most 128 sub-identifiers in a value,
and each sub-identifier has a maximum value of 2^32 - 1
(4294967295 decimal). See [RFC2578], Section 3.5.
MIB Object Identifier Information Element
An IPFIX Information Element ("mibObjectIdentifier") that denotes
that a MIB Object Identifier (MIB OID) is exported in the
(Options) Data Record. See Section 11.2.2.1.
SMIv2 Terminology
The key words "MIB module", "MIB object", "INDEX", "AUGMENTS",
"textual convention", "columnar object", "conceptual row", and
"conceptual table" in this document are to be interpreted as
described in SMIv2 [RFC2578].
SMIv2 SYNTAX
The SYNTAX key words "INTEGER", "Integer32", "OCTET STRING",
"OBJECT IDENTIFIER", "BITS", "IpAddress", "Counter32", "Gauge32",
"TimeTicks", "Opaque", "Counter64", "Unsigned32", "SEQUENCE", and
"SEQUENCE OF" in this document are to be interpreted as described
in SMIv2 [RFC2578].
SNMP Context Terminology
The key words "snmpEngineID", "contextEngineID", and "contextName"
in this document are to be interpreted as described in [RFC3411].
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mibObjectValue Information Elements
"mibObjectValue Information Elements" refers to any and all of the
mibObjectValue Information Elements generically. Any restriction
or requirement in this document that refers to "mibObjectValue"
applies to the following Information Elements as defined in
Section 11.2.1: mibObjectValueInteger, mibObjectValueOctetString,
mibObjectValueOID, mibObjectValueBits, mibObjectValueIPAddress,
mibObjectValueCounter, mibObjectValueGauge,
mibObjectValueTimeTicks, mibObjectValueUnsigned,
mibObjectValueTable, and mibObjectValueRow.
Abstract Data Type
Abstract Data Types for IPFIX are defined in Section 3.1 of
[RFC7012]. This specification uses the Abstract Data Types
"unsigned8", "unsigned32", "unsigned64", "signed32", "octetArray",
"string", "ipv4Address", and "subTemplateList".
IE
Used as shorthand for "Information Element" [RFC7011] in the
figures.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in
[RFC2119].
4. High-Level Solution Overview
This document specifies a method for creating IPFIX Options Templates
that are used to export the extra data required to describe MIB
variables (see Section 5.1).
This allows IPFIX Templates to contain any combination of fields
defined by traditional IPFIX Information Element(s) and/or MIB Object
Identifier(s). The MIB Object Identifiers can reference either
non-columnar or columnar MIB object(s). Enterprise-specific MIB
Object Identifiers are also supported.
This document also defines two standard IPFIX Options Templates (see
Section 5.3) that are used as part of the mechanism to export MIB
object metadata:
o MIB Field Options Template (Section 5.3.1)
o MIB Type Options Template (Section 5.3.2)
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This document defines three classes of new IPFIX Information
Elements. These are used to export values from the MIB, export
required Object Identifier information, and optionally export type
data from a MIB module:
o MIB Object Value Information Elements (Section 11.2.1)
o MIB Field Options Information Elements (Section 11.2.2)
o MIB Type Information Elements (Section 11.2.3)
Additionally, this document defines two new IPFIX semantics that are
required for the new Information Elements:
o snmpCounter (Section 11.1.1)
o snmpGauge (Section 11.1.2)
Two common types defined in SMIv2 are conceptual rows and conceptual
tables. It is desirable that exporting a complete or partial
conceptual row be simple and efficient. This is accomplished by
using IPFIX Structured Data [RFC6313] to reduce repetition of Object
Identifier and indexing data.
To allow the use of individual columnar objects that make up a
conceptual row, a method is also specified to explain that a MIB
object is indexed by other fields in the same Data Flow. For an
individually indexed mibObjectValue, the index fields are sent in the
same way as any of the other fields in the same Data Record and may
be mibObjectValue Information Element(s) or other existing
Information Element(s).
Also, in some cases Exporters may not want (or be able) to export the
full information on how the MIB objects being exported are indexed.
This may be because the MIB object is being used purely as type
information or the Exporting Process may not have knowledge of the
indexing required. Therefore, providing index information for
columnar objects is optional.
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5. MIB Object Value Information Elements and the MIB Field Options
Template
This document defines new mibObjectValue Information Elements (in
Section 11.2.1). These are used to export MIB objects as part of
standard IPFIX Templates. The mibObjectValue Information Elements
contain the actual data values.
The Metering Process or Exporting Process may extract the data values
for mibObjectValue Information Elements from a Process that resides
on the same device or may capture or create the data required to
match the definition of the MIB object. In particular, exporting a
value of a MIB object defined in a certain MIB module does not imply
that the SNMP process on the device supports that MIB module.
The main issue that arises from exporting values of MIB objects in
IPFIX is that MIB Object Identifiers do not fit into the standard
IPFIX Template format [RFC7011], as this only provides a 16-bit
Information Element identifier.
The values of a MIB object could be exported using a MIB-specific
Information Element, without providing any Object Identifiers.
However, without exporting the actual MIB OID, the full type of the
data would be unknown, and every field containing MIB object data
would appear identical. Without knowing which OID the contents of a
field map to, the data would be incomprehensible to a Collector.
For the values in the mibObjectValue Information Elements to be
understandable, more meta-information about the mibObjectValue
Information Elements must be sent as part of the IPFIX export. The
required minimum information to understand each field that is being
exported is provided in Section 5.3.1.
One approach to this problem would be to extend the IPFIX standard to
allow extended Field Specifiers so that metadata about fields can be
included in Data Templates. This would, however, require a new
version of the IPFIX standard that may not be backward compatible.
However, future versions of IPFIX may export the required MIB
metadata as part of newly defined IPFIX Set versions.
This document defines a MIB Field Options Template to export the
extra meta-information required for mibObjectValue Information
Elements. This is a standard IPFIX Options Template Set that
includes a minimum set of required fields (see Section 5.3.1) and may
include extra fields to provide more meta-information about one of
the mibObjectValue Information Elements.
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The MIB Field Options export tells the Collecting Process the OID for
the MIB object type definition for the following (Template, field).
5.1. MIB Field Options Architecture
Four IPFIX Sets are used together to export a Flow that contains
mibObjectValue Information Elements. These are:
1. A Template Set that includes the mibObjectValue Information
Element.
The Template Set informs the Collector that a MIB object value
of length N will be exported. This Set may also be an Options
Template Set.
2. A MIB Field Options Template Set.
The MIB Field Options Template describes which metadata will
be sent for each mibObjectValue Information Element being
exported.
3. A MIB Field Options Data Set.
The MIB Field Options Data Set includes the metadata for each
MIB object (i.e., the mibObjectIdentifier or
mibSubIdentifier). The metadata about the mibObjectValue
Information Elements only needs to be resent as per normal
Template refreshes or resends.
4. A Data Set.
The Data Set contains only the actual data extracted from the
MIB or described by the MIB module.
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Figure 2 shows the IPFIX Message structure for a MIB field in a
Template Set.
+-------------------------------------------------------+
| IPFIX Message Header |
+-------------------------------------------------------+
| Template Set (A) |
+-------------------------------------------------------+
| Options Template Set (B) (MIB Field Options Template) |
+-------------------------------------------------------+
| Data Set (B) (MIB Field Options Data) |
+-------------------------------------------------------+
| Data Set (A) |
+-------------------------------------------------------+
Figure 2: IPFIX Message Structure for a MIB Field in a Template Set
The MIB Field Options Template defines MIB Field Options
Data Records. The MIB Field Options Data Records annotate the Data
Template with mibObjectValue metadata. Together, the Data Template
and MIB Field Options Data Records define the Data Records that will
be exported.
The Data Records (A) have a dependency on the two Templates and the
MIB Field Options Data Records.
More Data Sets that use the same mibObjectValue Information Element
can then be sent in subsequent packets.
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Figure 3 shows the relationships between the Sets discussed above.
+------------------------------+
|MIB Field Options Template (B)|
+------------------------------+
|(templateId, elementIndex) |
+------------------------------+
| mibOID |
+------------------------------+
|
| Defines
V
+------------------------+ +--------------------------+
| Data Template (A) | |MIB Field Options Data (B)|
+------------------------+ +--------------------------+
|Field 0 - regular IE | | |
+------------------------+ +--------------------------+
|Field 1-mibObjectValue | <----------- | (X,1) = OID |
+------------------------+ Annotates +--------------------------+
|Field 2-mibObjectValue | <----------- | (X,2) = OID |
+------------------------+ +--------------------------+
| |
|------------------------------------/
|
| Defines
|
V
+------------------------+
| Data Records (A) |
|------------------------|
| Field 0 data |
+------------------------+
| Field 1 data |
+------------------------+
| Field 2 data |
+------------------------+
Figure 3: Relationships between Sets
5.2. IPFIX and MIB Data Model
[RFC2578], Section 7.1 specifies that the SYNTAX clause for a MIB
object defines the abstract data structure of an object and what it
must contain:
"The data structure must be one of the following: a base type, BITS,
or a textual convention. (SEQUENCE OF and SEQUENCE are also possible
for conceptual tables, see section 7.1.12)."
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For each of the SYNTAX clause options, this document specifies
exactly which mibObjectValue Information Element to use.
If a MIB object to be exported is a textual convention, the
definition of the textual convention must be consulted and the SYNTAX
clause used to determine the correct base type. This may recurse if
the textual convention is defined in terms of another textual
convention, but this should end at a base type.
If the SYNTAX clause contains a textual convention or sub-typing
(e.g., integerSubType, octetStringSubType) [RFC2578], the
mibObjectSyntax Information Element SHOULD be used to export this
detail to the Collecting Process.
The options for the SYNTAX clause are then mapped as follows:
+-------------+-------------------+---------------------------------+
| Section in | SYNTAX | mibObjectValue Information |
| RFC 2578 | | Element |
+-------------+-------------------+---------------------------------+
| 7.1.1 | INTEGER/Integer32 | mibObjectValueInteger |
| 7.1.2 | OCTET STRING | mibObjectValueOctetString |
| 7.1.3 | OBJECT IDENTIFIER | mibObjectValueOID |
| 7.1.4 | BITS | mibObjectValueBits |
| 7.1.5 | IpAddress | mibObjectValueIPAddress |
| 7.1.6 | Counter32 | mibObjectValueCounter |
| 7.1.7 | Gauge32 | mibObjectValueGauge |
| 7.1.8 | TimeTicks | mibObjectValueTimeTicks |
| 7.1.9 | Opaque | mibObjectValueOctetString |
| 7.1.10 | Counter64 | mibObjectValueCounter |
| 7.1.11 | Unsigned32 | mibObjectValueUnsigned |
| 7.1.12 | SEQUENCE | mibObjectValueRow |
| 7.1.12 | SEQUENCE OF | mibObjectValueTable |
+-------------+-------------------+---------------------------------+
Table 1: SMIv2 SYNTAX to mibObjectValue Types
Values are encoded as per the standard IPFIX encoding of Abstract
Data Types. The only new encoding reference in this document is that
Object Identifiers (OIDs) will be encoded as per ASN.1/BER [X.690] in
an octetArray.
The mibObjectValue and mibObjectIdentifier Information Elements are
standard IPFIX fields. Therefore, the E bit of the mibObjectValue or
mibObjectIdentifier Information Elements is set to 0.
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The MIB object being exported may be defined in an enterprise-
specific MIB module, but the Information Elements defined in this
standard are still exported with the E bit set to 0. The OID being
exported indicates that the MIB object was defined in an
enterprise-specific MIB module.
5.3. MIB Field Options - Specifications and Required Fields
For each mibObjectValue Information Element that is defined in an
IPFIX Template, a MIB Field Options Data Record will be exported that
provides the required minimum information to define the MIB object
that is being exported (see Section 5.3.1).
The MIB Field Options Data Records are defined in a Template referred
to in this document as a MIB Field Options Template with the format
specified in Section 5.4.
The MIB Field Options Template and MIB Field Options Data Records
MUST be exported in the same IPFIX Message as any Template that is
using a mibObjectValue Information Element. Note that this places an
implicit size constraint on the export.
This whole set of Templates and MIB Field Options Data Records MUST
all be exported prior to the corresponding Data Records that depend
upon them. That is, the export order MUST be:
1. Data Template for mibObjectValue Information Elements (Set ID 2)
2. MIB Field Options Template (Set ID 3)
3. MIB Field Options Data Records (Set ID >= 256)
4. MIB Object Value Data Records (Set ID >= 256)
Note that the ID of an identical MIB Field Options Template that has
already been exported MAY be reused without exporting the Template
again.
IPFIX Set IDs are defined in Section 3.3.2 of [RFC7011]. A value of
2 indicates a Template Set, a value of 3 indicates an Options
Template Set, and values 256 and above indicate Data Sets.
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5.3.1. MIB Field Options Template
Three fields are REQUIRED to unambiguously export a standalone
mibObjectValue Information Element with a MIB Field Options Template:
o (scope) templateId [IANA-IPFIX]
o (scope) informationElementIndex [IANA-IPFIX]
o mibObjectIdentifier (Section 11.2.2.1) or mibSubIdentifier
(Section 11.2.2.2)
These are the minimum fields required in a MIB Field Options Template
(see Section 5.4.2).
The mibObjectIdentifier is used to provide the OID for all
mibObjectValue Information Elements exported, except when IPFIX
Structured Data [RFC6313] is being used to export a conceptual row
(see Section 5.8.2).
While the following are optional, they are nevertheless RECOMMENDED
in certain circumstances, as described in the referenced sections:
o mibCaptureTimeSemantics
(discussed in Section 5.4.5; Information Element defined in
Section 11.2.2.4)
o mibIndexIndicator
(discussed in Section 5.8.5; Information Element defined in
Section 11.2.2.3)
o mibContextEngineID
(discussed in Section 5.6; Information Element defined in
Section 11.2.2.5)
o mibContextName
(discussed in Section 5.6; Information Element defined in
Section 11.2.2.6)
5.3.2. MIB Type Options Template
There are also fields that provide type information from a MIB object
definition that MAY be exported to a Collecting Process.
Type information is statically defined in a MIB module; it is not
expected to change. However, the additional information about the
MIB object may help a Collecting Process that does not have access to
the MIB module.
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To export a MIB Type Options Template, the mibObjectIdentifier is
RECOMMENDED as a Scope Field so that it matches the MIB Field Options
Template. Any combination of the other MIB Type fields may be
included.
o (scope) mibObjectIdentifier (see Section 11.2.2.1)
o mibObjectName (see Section 11.2.3.1)
o mibObjectDescription (see Section 11.2.3.2)
o mibObjectSyntax (see Section 11.2.3.3)
o mibModuleName (see Section 11.2.3.4)
5.4. MIB Field Options Template Formats
5.4.1. Data Template Containing a mibObjectValue Field
The Template Record format of a Template that uses a mibObjectValue
Information Element is identical to the standard IPFIX format as
defined in [RFC7011], so a field using a mibObjectValue Information
Element is specified using standard IPFIX Field Specifiers per
[RFC7011].
The only extra requirement on a Template Record using one or more
mibObjectValue Information Elements is that it MUST export the
required metadata specified in Section 5.3.1 for EACH mibObjectValue
Information Element.
If multiple MIB Field Options Data Records that refer to a
mibObjectValue are received, the latest MUST be used. This matches
the expected behavior of IPFIX Templates.
There is a one-to-one mapping between each mibObjectValue Information
Element and a MIB Field Options Data Record.
A MIB Field Options Template and corresponding Data Record MUST be
exported to provide the minimum required metadata.
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Figure 4 shows an IPFIX Template Set using a mibObjectValue
Information Element.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = Existing IPFIX Field | Field Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = <mibObjectValue> | Field Length (MIB) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 4: IPFIX Template Set Using mibObjectValue Information Element
Where:
<mibObjectValue>
One of the mibObjectValue IPFIX Information Elements that
denotes that MIB object data (i.e., the value of a MIB object)
will be exported in the (Options) Data Record.
This could be any one of the mibObjectValue Information
Elements defined in Section 11.2.1: mibObjectValueInteger,
mibObjectValueOctetString, mibObjectValueOID,
mibObjectValueBits, mibObjectValueIPAddress,
mibObjectValueCounter, mibObjectValueGauge,
mibObjectValueTimeTicks, mibObjectValueUnsigned,
mibObjectValueTable, and mibObjectValueRow.
When a mibObjectValue Information Element is used, the MIB
Object Identifier ("mibObjectIdentifier") MUST be exported via
a MIB Field Options Template and MIB Field Options Data Record.
See Section 5.3.1.
Field Length (MIB)
The length of the encoded MIB object data in the corresponding
Data Records, in octets. See [RFC7011] for a detailed
definition. Note that the Field Length can be expressed using
reduced-size encoding per [RFC7011]. Note that the Field
Length may be encoded using variable-length encoding per
[RFC7011].
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5.4.2. MIB Field Options Template
The MIB Field Options Template is a standard Options Template that
defines the fields that will be exported to provide enough metadata
about a mibObjectValue Information Element so that the Collector can
tie the data values in the mibObjectValue Information Element back to
the definition of the MIB object.
All MIB Field Options Templates contain the fields specified in
Section 5.3.1.
Figure 5 shows the required fields to export a mibObjectIdentifier
for the MIB Field Options Template format.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 5: MIB Field Options Template Format - Required Fields
Where:
templateId
The first Scope Field is an IPFIX Information Element that
denotes that a Template Identifier will be exported as part of
the MIB Field Options Data Record. This Template Identifier,
paired with an index into that Template (the
"informationElementIndex" field), uniquely references one
mibObjectValue Information Element being exported.
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informationElementIndex
The second Scope Field is an IPFIX Information Element that
denotes a zero-based index into the fields defined by a
Template. When paired with a "templateId", this uniquely
references one mibObjectValue Information Element being
exported.
mibObjectIdentifier
An IPFIX Information Element that denotes the MIB Object
Identifier for the mibObjectValue Information Element exported
in the (Options) Template Record.
When a MIB Object Value Information Element is used, the MIB
Object Identifier MUST be specified in the MIB Field Options
Template Record or specified by other means.
The Object Identifier is encoded in the IPFIX Data Record in
ASN.1/BER [X.690] format.
Variable-length encoding SHOULD be used with the
mibObjectIdentifier so that multiple MIB OIDs of different
lengths can be exported efficiently. This will also allow
reuse of the MIB Field Options Template.
Variable-length encoding is indicated by the Field Length value
of 65535, per Sections 3.2 and 7 of [RFC7011]. The RECOMMENDED
use of variable-length encoding for mibObjectIdentifier fields
is indicated in subsequent figures by placing 65535 in the
relevant length fields.
5.4.3. MIB Field Options Data Records
The MIB Field Options Data Records conform to the Template
Specification in the MIB Field Options Template. There may be
multiple MIB Field Options Data Records exported.
The Collecting Process MUST store all received MIB Field Options Data
information for the duration of each Transport Session, because the
Collecting Process will need to refer to the extra meta-information
to fully decode each mibObjectValue Information Element.
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Figure 6 shows the format of the exported MIB Field Options
Data Record, detailing the metadata that will be exported to match
the Template in Figure 5.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID | Length = N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId | informationElementIndex |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... mibObjectIdentifier (continued) ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId | informationElementIndex |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... mibObjectIdentifier (continued) ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 6: Format of MIB Field Options Data Record
VLEN contains the variable length of the mibObjectIdentifier per
Section 7 of [RFC7011].
5.4.4. Options Template Containing a mibObjectValue Field
The Options Template Record format of a Template that uses a
mibObjectValue Information Element is identical to the standard
format as defined in [RFC7011]. The mibObjectValue Information
Element is specified using standard Field Specifiers per [RFC7011].
A mibObjectValue Information Element can be either a Scope Field or a
non-Scope Field in an Options Template Record.
The only extra requirement on an Options Template Record using one or
more mibObjectValue Information Elements is that it MUST export the
required metadata specified in Section 5.3.1 for EACH mibObjectValue
Information Element.
An IPFIX Options Template Record MUST export a MIB Field Options
Template and Data Record to provide the minimum required metadata for
each mibObjectValue Information Element.
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Figure 7 shows an IPFIX Options Template Set using an existing IPFIX
field as a Scope Field and with a mibObjectValueInteger Information
Element as a non-Scope Field, while Figure 8 shows an IPFIX Options
Template Set using a mibObjectValueInteger Information Element as a
Scope Field with an existing IPFIX field as a non-Scope Field.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 18 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 1 |0| IE = Existing IPFIX Field |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 7: IPFIX Options Template Set Using a Non-Scope
mibObjectValueInteger Field
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 18 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 1 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |0| IE = Existing IPFIX Field |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 8: IPFIX Options Template Set Using a Scope
mibObjectValueInteger Field
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5.4.5. MIB Field Options Template with Semantics Fields
A MIB Field Options Template MAY specify that extra Information
Elements will be exported to record how the mibObjectValue was
collected.
Alternatively, one of the existing IPFIX observationTime* elements
[IANA-IPFIX] may be exported to specify exactly when the value was
collected.
Figure 9 shows the MIB Field Options Template for a non-columnar
field with Semantic Data.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibCaptureTimeSemantics|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 9: MIB Field Options Template for a Non-columnar Field
with Semantic Data
Where:
mibObjectIdentifier
Note the use of variable-length encoding for this field.
mibCaptureTimeSemantics
The MIB Capture Time Semantics IPFIX Information Element, as
defined in Section 11.2.2.4.
It is RECOMMENDED to include this field when exporting a
mibObjectValue Information Element that specifies counters or
statistics, particularly for situations with long-lived Flows.
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5.4.6. MIB Field Options Template with Extra MIB Object Details
The OID exported within the mibObjectIdentifier IPFIX Information
Element provides an OID reference to a MIB object type definition
that will fully describe the MIB object data being exported.
However, an Exporting Process MAY decide to include some extra fields
to more fully describe the MIB object that is being exported with a
mibObjectValue Information Element.
This can be helpful if the Collecting Process may not have access to
the MIB module.
The Exporting Process can either include the fields with extra object
details as part of the MIB Field Options Template or export a
separate Options Template and a Data Record that maps MIB OIDs in
mibObjectIdentifier fields to the object details.
If only a few fields are being exported, then including extra type
data in the MIB Field Options export will be more efficient.
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The MIB Field Options Template for a non-columnar field with extra
MIB object details is shown in Figure 10.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 38 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 7 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibObjectSyntax |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibObjectName |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibObjectDescription |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibModuleName |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 10: MIB Field Options Template for a Non-columnar Field
with Extra MIB Object Details
Where:
mibObjectSyntax
The MIB object syntax string as defined in Section 11.2.3.3.
Note that a separate mibObjectSyntax Information Element is
required (rather than extend the existing "IPFIX Information
Elements" subregistry [IANA-IPFIX] that contains
informationElementDataType) because the SYNTAX clause could
contain almost any name.
mibObjectName
The textual name of a mibObjectIdentifier object.
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mibObjectDescription
The textual description for a mibObjectIdentifier.
mibModuleName
The textual name of the MIB module that defines a MIB object.
Note the use of variable-length encoding for the
mibObjectIdentifier, mibObjectSyntax, mibObjectName,
mibObjectDescription, and mibModuleName, since these are all
string fields.
The MIB details can be exported in Data Records specified using a
regular IPFIX Options Template Record [RFC7011], as shown in
Figure 11. This may be more efficient, as the bulk of this data is
text based and SHOULD be exported only once to the Collecting Process
if there are many MIB objects being exported. This prevents this
large textual data from being included for every use of a
mibObjectValue Information Element.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 30 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 1 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibObjectSyntax |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibObjectName |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibObjectDescription |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |0| IE = mibModuleName |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 11: Alternative mibObjectIdentifier Options Template Set
with Object Details
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5.5. Use of Field Order in the MIB Field Options Template
The MIB Field Options Template export makes use of the
informationElementIndex [IANA-IPFIX] to specify which field in the
Template the metadata relates to; this avoids any ordering
constraints on the Data Template. The mibObjectValue Information
Elements in an IPFIX export can be in any order in the export packet.
However, fields used as an INDEX MUST be in the same order as the
order specified in the INDEX clause of the conceptual row MIB object.
The informationElementIndex specifies which field in the Template
extra information is being provided for.
This is analogous to standard IPFIX Template Sets, which also specify
the order of the fields and provide their type and size.
If the Template changes such that the order is different, then the
MIB Field Options Data MUST be resent to reflect the new ordering. A
new Template ID MUST be used to reflect that the ordering has
changed. Older MIB Field Options Data may refer to the incorrect
field.
A templateId [IANA-IPFIX] is only locally unique within a combination
of an Observation Domain and Transport Session. As such, each MIB
Field Options Data Record can only refer to templateIds within the
same Observation Domain and session.
5.6. Identifying the SNMP Context
Each MIB OID is looked up in a specific context, usually the default
context. If exporting a MIB OID value that isn't in the default
context, then the context MUST be identified by including the
mibContextEngineID (see Section 11.2.2.5) and mibContextName (see
Section 11.2.2.6) fields in the MIB Field Options Template and
associated MIB Field Options Data Records, or be included in the same
Template as the mibObjectValue field.
This context data MUST be included for each field that is not in the
default context.
The context information MAY be exported as part of the Template that
includes the mibObjectValue Information Element, or the context
information MAY be exported in the MIB Field Options Data Record that
refers to the field. Context fields exported in the same Template
MUST take precedence over those that refer to the Template. Context
fields MUST apply to all mibObjectValue Information Elements in the
same Template, and there MUST NOT be duplicates of mibContextName or
mibContextEngineID in a Template.
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So, a MIB Field Options Template MAY specify no context information,
just the context engine ID or both the context engine and context
name. This allows the Exporter to export the bulk of data in the
default context and only tag those items that are required.
Since the MIB Field Options Template applies for all the Data Records
of a Template, using context fields in the MIB Field Options Data
Template requires that each mibContextEngineID / mibContextName pair
have its own Template.
5.7. Template Management
Templates are managed as per Section 8 of [RFC7011], with the
additional constraint that the MIB Field Options Template and MIB
Field Options Data Records MUST be exported in the same IPFIX Message
as any (Options) Template Record that uses a mibObjectValue
Information Element.
When exporting over a Stream Control Transmission Protocol (SCTP)
transport [RFC4960], the MIB Field Options Data Records MUST be
exported reliably and in the same SCTP stream as their associated
Templates per [RFC6526].
If a Template using a mibObjectValue Information Element is resent
for any reason, the Data Records it depends on MUST be sent as well.
If a Template is replaced with a new (Options) Template, then a new
MIB Field Options Data Record MUST be sent with the replacement
referencing the new Template ID.
An Exporting Process SHOULD reuse MIB Field Options Template IDs when
the Templates are identical. Each (Options) Template Record MUST
still be accompanied by a copy of the MIB Field Options Template.
5.7.1. Large Messages
The requirement to export the MIB Field Options Template and MIB
Field Options Data Records in the same IPFIX Message as any (Options)
Template Record that uses a mibObjectValue Information Element may
result in very large IPFIX Messages.
In environments with restricted Message sizes, and only when a
reliable SCTP transport is being used, the MIB Field Options
Template, MIB Field Options Data, Data Template, and Data Records MAY
be exported in separate Messages in the same SCTP stream, provided
that their order is maintained.
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5.7.2. Template Withdrawal and Reuse
Data Records containing mibObjectValue Information Elements MUST NOT
be exported if their corresponding Data Template or MIB Field Options
Template has been withdrawn, since the MIB Field Options Template
MUST be exported in the same IPFIX Message as the Data Template that
it annotates, except as allowed by the caveat mentioned in
Section 5.7.1.
MIB Field Options Template IDs MUST NOT be reused while they are
required by any existing Data Templates.
5.8. Exporting Conceptual Rows and Tables
There are three approaches for an IPFIX Exporting Process to export
the values of columnar objects:
1. Ignoring the indexing of columnar objects
2. Exporting conceptual rows / table objects using IPFIX Structured
Data [RFC6313]
3. Exporting individual indexed columnar objects
Firstly, a subordinate columnar object may be used purely as a data
type. In this case, there is no index information or relation to a
conceptual row object provided by the Exporting Process.
Secondly, mibObjectValueRow or mibObjectValueTable can be used to
export partial or complete conceptual rows, using IPFIX Structured
Data [RFC6313].
Thirdly, in a mixed option/data IPFIX/MIB Template, the
mibObjectValue Information Element can have the values of the INDEX
clause of the conceptual row provided by other fields in the
Data Record. In this case, each mibObjectValue Information Element
must specify which other field(s) in the Template is providing the
index information.
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RFC 8038 Exporting MIB Variables with IPFIX May 2017
5.8.1. Exporting Conceptual Rows - Indexing
This document defines two forms of indexing that can be used for
conceptual row MIB objects:
Indexing based on IPFIX Structured Data [RFC6313] is used solely by
the mibObjectValueRow Information Element. Each conceptual row of
the MIB object corresponds to a single Data Record exported. The
index fields defined in the INDEX clause of the MIB object MUST all
be present in the same order as the Scope Fields. This allows a
simple table export of a conceptual row MIB object without any extra
fields required to indicate which fields make up the conceptual row
INDEX.
Field-based indexing is used by giving each mibObjectValue
Information Element a mibIndexIndicator to flag the required index
fields. This allows complex indexing or mixing of existing IPFIX
Information Elements with MIB fields, with minimum overhead. It also
allows multiple columnar MIB objects from different conceptual rows
to be exported with complete indexing in one IPFIX Template.
5.8.2. Exporting Conceptual Rows - mibObjectValueRow
The simplest approach to exporting a complete or partial conceptual
row object is done with the mibObjectValueRow Information Element.
This is an IPFIX Structured Data subTemplateList Information Element
as detailed in [RFC6313]. The Template specified MUST be an Options
Template. It also MUST have the fields specified in the INDEX clause
of the conceptual row object as the Scope Fields in the MIB Field
Options Template and Data Set.
An overview of this architecture is given in Figure 12. This shows
that the full MIB object type definition OID is exported for the
mibObjectValueRow conceptual row field but that the individual
columnar objects only require the sub-identifier to be exported. To
make the diagram clearer, the Templates for the MIB Field Options
Templates are not shown.
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RFC 8038 Exporting MIB Variables with IPFIX May 2017
+---------------------------+ +------------------------+
| Data Template | | MIB Field Options Data |
| | | |
| mibObjectValueRow |<---| OID |
+---------------------------+ +------------------------+
|
| +-----------------------+ +------------------------+
| | Options Template | | MIB Field Options Data |
| | | | |
| | Scope mibObjectValue* |<---| mibSubIdentifier |
| | mibObjectValue* |<---| mibSubIdentifier |
| +-----------------------+ +------------------------+
| |
V V
+---------------------------+
| Data Flows |
| |
| subTemplateList (1 entry) |
+---------------------------+
Figure 12: Architecture for Exporting Conceptual Rows
with mibObjectValueRow
The mibIndexIndicator is not required for each individual
mibObjectValue Information Element, as mibObjectValueRow provides a
structure that includes the index details.
When indexing based on IPFIX Structured Data [RFC6313] is used, all
Scope Fields MUST be the INDEX objects in the same order as defined
in the INDEX clause of the conceptual row being exported.
Each conceptual table MIB object has two related OIDs. There is an
OID that refers to the table with the syntax of SEQUENCE OF and an
OID that refers to each entry or conceptual row with the syntax of
SEQUENCE. The OID for the SEQUENCE of a conceptual row MUST be
exported.
For example, in the IF-MIB [RFC2863], the OID for ifEntry should be
exported rather than the OID for ifTable. The OID for the table (in
this case, ifTable) can be derived by removing one sub-identifier
from the ifEntry OID.
The full OID for the conceptual row MIB object type definition being
exported with the mibObjectValueRow Information Element MUST be
exported. However, the fields that are members of the conceptual row
need not have the full OID of their MIB object type definition
exported. Instead, the mibSubIdentifier Information Element can be
used to document which entry in the conceptual row the field is.
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RFC 8038 Exporting MIB Variables with IPFIX May 2017
In this case, the exported Flow will contain a single complete or
partial row from a table inside a single field of the Data Record.
There may be MIB objects that are specified in the INDEX of the
conceptual row but not columnar objects of the same conceptual row;
for these, the Exporter MUST provide the full OID in a
mibObjectIdentifier field.
So, for a conceptual row object with the OID "1.2.3.4.5.6" the OID of
the type definitions for columnar objects "1.2.3.4.5.6.1"
"1.2.3.4.5.6.2" can be exported with just a mibSubIdentifier of "1"
and "2", respectively.
The mibObjectValue Information Elements exported using the
mibObjectValueRow export MUST all either be objects defined in the
INDEX clause, columnar objects of the same conceptual row object, or
columnar objects that augment the same conceptual row.
The IPFIX Structured Data [RFC6313] subTemplateList format requires
the Structured Data Type Semantics to be specified. Unless there is
a more appropriate option in the "IPFIX Structured Data Types
Semantics" subregistry [IANA-IPFIX], the "undefined" Structured Data
Type Semantics can be used.
Figure 13 shows an IPFIX Template for an IPFIX Structured Data
[RFC6313] export of a conceptual row, while Figure 14 shows an IPFIX
Options Template for a complete conceptual row with five columns and
two index fields. Figure 15 shows the MIB Field Options Template for
a conceptual row field. Figure 16 shows the MIB Field Options
Template for the columns inside the conceptual row. Figure 17 shows
the OID Data for the conceptual row that will be exported.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 300 | Field Count = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueRow | Field Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 13: IPFIX Template for a Conceptual Row
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 30 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 301 | Field Count = 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = mibObjectValue INDEX1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |0| IE = mibObjectValue INDEX2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |0| IE = mibObjectValue COLUMN3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |0| IE = mibObjectValue COLUMN4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |0| IE = mibObjectValue COLUMN5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 14: IPFIX Options Template for a mibObjectValueRow
with Five Columns and Two Index Fields
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 302 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 15: MIB Field Options Template for a Conceptual Row Object
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Where:
templateId
The templateId for the MIB option that will be exported.
mibObjectIdentifier
The MIB OID for the conceptual row that is being exported.
Note the use of variable-length encoding for this field.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 303 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 16: MIB Field Options Template for Columnar Objects
of a Conceptual Table
Where:
templateId
The templateId used will be for the Template referred to in the
subTemplateList of the mibObjectValueRow that will be exported.
mibSubIdentifier
The sub-identifier that specifies the columnar object's ID
within the conceptual row.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 302 | Length = N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 300 | informationElementIndex |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... mibObjectIdentifier (continued) ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 303 | Length = N |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 301 | informationElementIndex |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier | templateId = 301 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex | mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 301 | informationElementIndex |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier | templateId = 301 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex | mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 301 | informationElementIndex |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 17: mibOption Data Record for the Conceptual Row
Where:
mibObjectIdentifier
Will contain the OID for the conceptual row as a whole.
mibSubIdentifier
The mibSubIdentifier fields will contain the extra
sub-identifier that, when added to the OID for the conceptual
row, gives the full OID for the object.
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5.8.3. Exporting Conceptual Rows - AUGMENTS
SMIv2 defines conceptual rows as having either an INDEX clause or an
AUGMENTS clause. Conceptual row definitions with an AUGMENTS clause
extend an existing base conceptual row with an INDEX clause. It is
not possible in SMIv2 to augment a conceptual row that itself has an
AUGMENTS clause. The base table and the augmentation have an
identical INDEX.
Since augmentations allow adding extra columns to existing tables, it
is beneficial to be able to support them easily in IPFIX exports of
conceptual rows.
The mibObjectValueRow OID MAY refer to either the base table with the
INDEX clause or a conceptual row with an AUGMENTS clause. The
mibSubIdentifier in any MIB Field Options Data Record MUST always
refer to the OID exported for the mibObjectValueRow Information
Element.
If the mibObjectValueRow OID refers to a base table, then any extra
columns from conceptual rows with an AUGMENTS clause MUST have their
full OID exported.
If the mibObjectValueRow OID refers to a conceptual row that augments
another conceptual row using the AUGMENTS clause, then any MIB fields
from the original table's INDEX or columnar objects MUST NOT use the
mibSubIdentifier and MUST instead export the full OID in a
mibObjectIdentifier.
If the mibObjectValueRow refers to an augmenting conceptual row, the
Scope Fields of the Template used in the subTemplateList MUST have
the index fields from the base table, in the same order as its scope.
This is identical to the Scope Field requirements for conceptual rows
with an INDEX clause.
This flexibility is provided so that the conceptual rows with the
most columns can be exported using the more efficient
mibSubIdentifier. For example, exporting a complete set of
augmentation columns would only require the full OIDs for the MIB
objects in the INDEX.
It is possible to export MIB object columns from multiple augmenting
conceptual rows. If this is done, then the base table SHOULD be used
as the main OID for the mibObjectValueRow.
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5.8.4. Exporting Conceptual Tables - mibObjectValueTable
Multiple rows of a conceptual table can be exported in the
mibObjectValueTable Information Element (Section 11.2.1.10). This
allows a set of conceptual rows corresponding to a conceptual table
to be exported as a single field. Therefore, a complete set of rows
can be exported as a single field with other Information Elements in
a Template. In this fashion, several complete conceptual tables
could be exported in one packet.
As also specified for mibObjectValueRow (Section 5.8.2), the more
specific (i.e., full) OID of the SEQUENCE entity MUST be exported.
The format of mibObjectValueTable is identical to mibObjectValueRow,
except that the length of the subTemplateList may be zero or more
entries.
All the other, i.e., non-length, requirements for mibObjectValueRow
in Section 5.8.2 apply to mibObjectValueTable.
An overview of this architecture is given in Figure 18. This
architecture is similar to the architecture shown in Figure 12.
+---------------------------+ +------------------------+
| Data Template | | MIB Field Options Data |
| | | |
| mibObjectValueTable |<---| OID |
+---------------------------+ +------------------------+
|
| +-----------------------+ +------------------------+
| | Options Template | | MIB Field Options Data |
| | | | |
| | Scope mibObjectValue* |<---| mibSubIdentifier |
| | mibObjectValue* |<---| mibSubIdentifier |
| +-----------------------+ +------------------------+
| |
V V
+-----------------------------+
| Data Flows |
| |
| subTemplateList (n entries) |
| row 1 |
| ... |
| row n |
+-----------------------------+
Figure 18: Architecture for Exporting Conceptual Tables
with mibObjectValueTable
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5.8.5. Exporting Columnar Objects: Using mibIndexIndicator
The other option for indexing a columnar object that is part of a
conceptual table is explicit indexing. In this case, the Options
Template Set scope may contain either non-index fields or columnar
MIB objects from multiple conceptual rows being exported. In this
case, each mibObjectValue Information Element requires the
mibIndexIndicator with the bits set for the fields that are used to
index that individual columnar object.
The index fields MUST be in the "correct" order as defined in the
conceptual row that each columnar object is a member of.
If a mibObjectValue Information Element that is being indexed using
mibIndexIndicator is being used as an Options Template Scope Field,
then all fields used to index that field MUST also be Scope Fields.
Figure 19 shows the MIB Field Options Template for an indexed MIB
columnar object.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibIndexIndicator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 19: MIB Field Options Template for an Indexed
MIB Columnar Object
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Where:
mibIndexIndicator
The MIB Index Indicator IPFIX Information Element that marks
which fields in the Data Record will act as INDEX values for
the exported MIB object.
The index data for a mibObjectValue will be other fields
contained in the same Data Record. The mibIndexIndicator marks
the fields whose value(s) should be added to the OID for the
MIB object type definition exported in mibObjectIdentifier to
get the OID for the instance of the MIB object.
Elements used to index MIB objects MUST be exported in the same
order as they are specified in the index field of the
conceptual table they belong to.
mibObjectIdentifier
Note the use of variable-length encoding for this field.
6. Example Use Cases
6.1. Non-columnar MIB Object: Established TCP Connections
The number of established TCP connections of a remote network device
could be monitored by configuring it to periodically export the
number of established TCP connections to a centralized Collector. In
this example, the Exporter would export an IPFIX Message every
30 minutes that contained Data Records detailing the number of
established TCP connections.
The table of data that is to be exported looks like:
+-------------------------+-----------------------+
| TIMESTAMP | ESTABLISHED TCP CONN. |
+-------------------------+-----------------------+
| StartTime + 0 seconds | 10 |
| StartTime + 60 seconds | 14 |
| StartTime + 120 seconds | 19 |
| StartTime + 180 seconds | 16 |
| StartTime + 240 seconds | 23 |
| StartTime + 300 seconds | 29 |
+-------------------------+-----------------------+
Table 2: Established TCP Connections
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The Template Record for such a Data Record will provide details for
the following two Information Elements:
1. flowStartSeconds from [IANA-IPFIX], Information Element 150: The
absolute timestamp of the first packet of this Flow.
2. tcpCurrEstab from [RFC4022], Object ID "1.3.6.1.2.1.6.9": The
number of TCP connections for which the current state is either
ESTABLISHED or CLOSE-WAIT.
Figure 20 shows the exported Template Set detailing the
Template Record for exporting the number of established TCP
connections.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 400 | Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = flowStartSeconds | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueGauge | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 20: Example of tcpCurrEstab Template Set
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Figure 21 shows the exported MIB Field Options Template Set detailing
the metadata that will be exported about the mibObjectValueGauge
Information Element in Template 400 in Template Record.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 401 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 21: Example of tcpCurrEstab MIB Field Options Template Set
Figure 22 shows the exported MIB Field Options Data Set detailing the
metadata that will be exported about the mibObjectValueGauge
Information Element in Template 400 in Template Record.
The OID for the MIB object tcpCurrEstab from [RFC4022], Object ID
"1.3.6.1.2.1.6.9", will be encoded in ASN.1/BER [X.690] as
"06072B060102010609" in the Data Record, which takes 9 octets.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 401 | Length = 18 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 400 | informationElementIndex = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN = 9 | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... mibObjectIdentifier = "1.3.6.1.2.1.6.9" ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... 06072B060102010609 ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 22: Example of tcpCurrEstab MIB Field Options Data Set
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Figure 23 shows the start of the Data Set for exporting the number of
established TCP connections (see Section 6.1).
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 400 | Length = 52 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| StartTime + 0 seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 10 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| StartTime + 60 seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 14 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| StartTime + 120 seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 19 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| StartTime + 180 seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| StartTime + 240 seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 23 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| StartTime + 300 seconds |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 29 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 23: Example of tcpCurrEstab Data Set
6.2. Enterprise-Specific MIB Object: Detailing CPU Load History
For the sake of demonstration, an enterprise-specific MIB object from
the CISCO-PROCESS-MIB [CISCO-PROCESS-MIB] is chosen. This example
would be valid with any enterprise-specific MIB module.
The CPU usage of a remote network device with one CPU could be
monitored by configuring it to periodically export CPU usage
information, i.e., the cpmCPUTotal1minRev from the proprietary
CISCO-PROCESS-MIB, Object ID "1.3.6.1.4.1.9.9.109.1.1.1.1.7", to a
centralized Collector.
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Although the cpmCPUTotal1minRev MIB object is a columnar object in a
conceptual row, if there is only one CPU no extra information is
conveyed by providing the index field. So, in this case, it is
acceptable to not export the cpmCPUTotalIndex MIB object. If there
were multiple CPUs, it would be appropriate to include the
cpmCPUTotalIndex field and specify the relationship.
In this example, the Exporter would export an IPFIX Message every
30 minutes that contained Data Records detailing the CPU 1-minute
busy average at 1-minute intervals.
The table of data that is to be exported looks like:
+-------------------------+---------------------+
| TIMESTAMP | CPU BUSY PERCENTAGE |
+-------------------------+---------------------+
| StartTime + 0 seconds | 10% |
| StartTime + 60 seconds | 14% |
| StartTime + 120 seconds | 19% |
| StartTime + 180 seconds | 16% |
| StartTime + 240 seconds | 23% |
| StartTime + 300 seconds | 29% |
+-------------------------+---------------------+
Table 3: CPU Usage Data
The Template Record for such a Data Record will provide details for
the following two Information Elements:
1. flowStartSeconds from [IANA-IPFIX], Information Element 150: The
absolute timestamp of the first packet of this Flow.
2. A mibObjectValueGauge for cpmCPUTotal1minRev, the overall CPU
busy percentage in the last 1-minute period.
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Figure 24 shows the exported Template Set detailing the
Template Record for exporting CPU Load (see Section 6.2).
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 402 | Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = flowStartSeconds | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueGauge | Field Length = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 24: Example of CPU Load Template Set
Figure 25 shows the exported Template Set detailing the MIB Field
Options Template for exporting CPU Load (see Section 6.2). Note:
This is identical to the MIB Field Options Template given in
Figure 21, so the same Template could have been reused.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 403 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 25: Example of CPU Load MIB Field Options Template Set
Figure 26 shows the exported MIB Field Options Data Set detailing the
metadata that will be exported about the mibObjectValueGauge
Information Element in Template 402 in Template Record (see
Section 6.2).
The OID for the cpmCPUTotal1minRev has been encoded using ASN.1/BER
to "060D2B0601040109096D0101010107" at 15 octets long.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 403 | Length = 24 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 402 | informationElementIndex = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN = 15 | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| "1.3.6.1.4.1.9.9.109.1.1.1.1.7" ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 060D2B0601040109096D0101010107 ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 26: Example of CPU Load MIB Field Options Data Set
Note that although cpmCPUTotal1minRev is 32 bits long, reduced-size
encoding [RFC7011] has been used to encode it within a single octet.
The encoding size was specified by setting the length for the
mibObjectValueGauge field to 1 octet in the main Data Template; see
Figure 24.
This example stresses that, even though the OID cpmCPUTotal1minRev is
enterprise-specific, the E bit for the mibObjectValueGauge and
mibObjectIdentifier is set to 0, because the mibObjectValueGauge and
mibObjectIdentifier Information Elements are not enterprise-specific.
That this data is from an Enterprise MIB is included in the OID that
includes an Enterprise ID.
The corresponding Data Set does not add any value for this example
and is therefore not displayed.
6.3. Exporting a Conceptual Row: The OSPF Neighbor Row
Many conceptual tables are already defined in standard and
proprietary MIBs. These can be exported with a minimum of overhead
by using the mibObjectValueRow. This allows the Exporting Process to
unambiguously define the INDEX for the entire conceptual row as the
Scope Fields of an Options Template Set. The use of a MIB Field
Options Template with mibSubIdentifier being used means that each
individual columnar object does not need to have its OID exported to
the Collector.
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RFC 8038 Exporting MIB Variables with IPFIX May 2017
The ospfNbrTable, defined in the OSPF MIB [RFC4750], consists of
ospfNbrEntry, which has the OID "1.3.6.1.2.1.14.10.1". Each
mibObjectValueRow Data Record will therefore correspond to an
ospfNbrEntry.
The following fields will be exported:
+------------------+----------------+-------------------------+-----+
| Object | ID | mibObjectValue | Len |
+------------------+----------------+-------------------------+-----+
| ospfNbrIpAddr | ospfNbrEntry 1 | mibObjectValueIPAddress | 4 |
| ospfNbrAddress- | ospfNbrEntry 2 | mibObjectValueInteger | 4 |
| -LessIndex | | | |
| ospfNbrRtrId | ospfNbrEntry 3 | mibObjectValueIPAddress | 4 |
| ospfNbrState | ospfNbrEntry 6 | mibObjectValueInteger | 1 |
+------------------+----------------+-------------------------+-----+
Table 4: OSPF Neighbor Entry Objects
The OIDs that will be used to export this table are shown in Table 5.
+------------------+-----------------------+---------------------+
| Entity | Full OID | Exported as |
+------------------+-----------------------+---------------------+
| ospfNbrEntry | 1.3.6.1.2.1.14.10.1 | 1.3.6.1.2.1.14.10.1 |
| ospfNbrIpAddr | 1.3.6.1.2.1.14.10.1.1 | 1 |
| ospfNbrAddress- | 1.3.6.1.2.1.14.10.1.2 | 2 |
| -LessIndex | | |
| ospfNbrRtrId | 1.3.6.1.2.1.14.10.1.3 | 3 |
| ospfNbrState | 1.3.6.1.2.1.14.10.1.6 | 6 |
+------------------+-----------------------+---------------------+
Table 5: OSPF OIDs
Figure 27 shows the Templates exported to support the
mibObjectValueRow. Figure 28 shows the example OID Data for the
conceptual row exported in mibObjectValueRow. Figure 29 shows the
example data export for a few neighbors in the table; Figure 29 also
shows a Data Record formatted as per IPFIX Structured Data [RFC6313]
and using the "undefined" (= 0xFF) semantic from the "IPFIX
Structured Data Types Semantics" subregistry [IANA-IPFIX]. Note that
the OID for ospfNbrEntry has been encoded using ASN.1/BER to
"06082B060102010E0A01" at 10 octets long.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 500 | Field Count = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueRow | Field Length = 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 501 | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = mibObjectValueIPAddress|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |0| IE = mibObjectValueIPAddress|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length = 22 | Template ID = 502 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Count = 3 | Scope Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = templateId | Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = informationElementIndex| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectIdentifier | Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 503 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 27: Example of ospfNbrEntry Template and Options Template Sets
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 502 | Length = 20 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 500 | informationElementIndex = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN = 10 | mibObjectIdentifier = "1.3.6.1.2.1.14.10.1" |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 06082B060102010E0A01 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Padding = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 503 | Length = 28 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 501 | informationElementIndex = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier = 1 | templateId = 501 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex = 1 | mibSubIdentifier = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 501 | informationElementIndex = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier = 3 | templateId = 501 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex = 3 | mibSubIdentifier = 6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 28: Example of ospfNbrEntry OID Data Export
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 500 | Length = 52 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 501 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrIpAddr = 192.0.2.1 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrAddressLessIndex = 0 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrRtrId = 1.1.1.1 |ospfNbrState=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 501 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrIpAddr = 192.0.2.2 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrAddressLessIndex = 0 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrRtrId = 2.2.2.2 |ospfNbrState=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 501 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrIpAddr = 192.0.2.3 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrAddressLessIndex = 0 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrRtrId = 3.3.3.3 |ospfNbrState=1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 29: Example of Data Export for ospfNbrEntry
6.4. Exporting Augmented Conceptual Row: Mapping IF-MIB ID to Name
The ifTable, defined in the IF-MIB [RFC2863], is augmented by the
ifXTable (defined in the same MIB module).
The OID of the ifEntry is 1.3.6.1.2.1.2.2.1, which is encoded using
ASN.1/BER to "06082B06010201020201" at 10 octets long, while the OID
of the augmenting ifXEntry is 1.3.6.1.2.1.31.1.1.1, which is encoded
using ASN.1/BER to "060A2B060102011F01010101" at 12 octets long.
This example demonstrates how columnar objects from the base
conceptual row and the augmenting row can be exported in a single
mibObjectValueRow Information Element.
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Table 6 shows the fields that will be exported.
+---------+------------------+-------+-------------------+
| ifIndex | ifType | ifMtu | ifName |
+---------+------------------+-------+-------------------+
| 1 | ethernetCsmacd:6 | 1500 | Ethernet 10 |
| 2 | ethernetCsmacd:6 | 1500 | Ethernet 20 |
| 3 | ethernetCsmacd:6 | 1500 | FastEthernet 30 |
+---------+------------------+-------+-------------------+
Table 6: IF-MIB Data
The OIDs that will be used to export this table are shown in Table 7.
+---------+------------------------+--------------------------------+
| Entity | Full OID | Exported as |
+---------+------------------------+--------------------------------+
| ifEntry | 1.3.6.1.2.1.2.2.1 | OID = 1.3.6.1.2.1.2.2.1 |
| ifIndex | 1.3.6.1.2.1.2.2.1.1 | subID = 1 |
| ifType | 1.3.6.1.2.1.2.2.1.3 | subID = 3 |
| ifMtu | 1.3.6.1.2.1.2.2.1.4 | subID = 4 |
| ifName | 1.3.6.1.2.1.31.1.1.1.1 | OID = 1.3.6.1.2.1.31.1.1.1.1 |
+---------+------------------------+--------------------------------+
Table 7: IF-MIB OIDs
Figure 30 shows the Templates exported to support the
mibObjectValueRow Information Element. Figure 31 shows the example
OID Data for the conceptual row exported in mibObjectValueRow to
match Table 7. Figure 32 shows the example data export as per
Table 6.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 600 | Field Count = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueRow | Field Length = 24 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 601 | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 1 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 1 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0|IE =mibObjectValueOctetString|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length = 22 | Template ID = 602 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Count = 3 | Scope Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = templateId | Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = informationElementIndex| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectIdentifier | Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 603 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 30: Example of Augmented ifEntry Template and
Options Template Sets
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 602 | Length = 40 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 600 | informationElementIndex = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN = 10 | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ifEntry = 1.3.6.1.2.1.2.2.1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 06082B06010201020201 | Padding = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 601 | informationElementIndex = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN = 12 | mibObjectIdentifier ifName ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ifName = 1.3.6.1.2.1.31.1.1.1.1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 060A2B060102011F01010101 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Padding = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 603 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 601 | informationElementIndex = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier = 1 | templateId = 601 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex = 1 | mibSubIdentifier = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 601 | informationElementIndex = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 31: Example of Augmented ifEntry OID Data Export
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 600 | Length = 68 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 601 | ifIndex = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ifType = 6 | ifMtu = 1500 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length = 11 | ifName = Ethernet 10 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 601 | ifIndex = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ifType = 6 | ifMtu = 1500 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length = 11 | ifName = Ethernet 20 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 601 | ifIndex = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ifType = 6 | ifMtu = 1500 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length = 15 | ifName = FastEthernet 30 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 32: Example of Data Export for Augmented ifEntry
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6.5. Exporting a Columnar Object: ipIfStatsInForwDatagrams
It may be that the full set of columnar objects that are supported by
a conceptual row are not required to be exported. Rather than use
the IPFIX Structured Data [RFC6313] method, the mibIndexIndicator
method can be used to provide the relationship between fields.
This example shows the MIB objects that are part of the INDEX of the
conceptual row being exported in the correct order and then being
referred to by using mibIndexIndicator.
This example shows the export of ipIfStatsInForwDatagrams from the
IP-MIB [RFC4293]. ipIfStatsInForwDatagrams is a columnar object that
is part of the ipIfStatsTable conceptual table. This is comprised of
ipIfStatsEntry conceptual rows.
The ipIfStatsTable conceptual table is indexed by ipIfStatsIPVersion
and ipIfStatsIfIndex.
The Options Template Record for the example Data Record contains the
following Information Elements:
1. ipIfStatsIPVersion (1.3.6.1.2.1.4.31.3.1.1) (Scope Field)
(encoded using ASN.1/BER to "060A2B06010201041F030101" at
12 octets long)
2. ipIfStatsIfIndex (1.3.6.1.2.1.4.31.3.1.2) (Scope Field)
(encoded using ASN.1/BER to "060A2B06010201041F030102" at
12 octets long)
3. ipIfStatsInForwDatagrams (1.3.6.1.2.1.4.31.3.1.12) (non-Scope
Field)
(encoded using ASN.1/BER to "060A2B06010201041F03010C" at
12 octets long)
Note that ipIfStatsIfIndex has been reduced-size encoded to 2 octets
in the following example. An exporting device with more interfaces
would use the full length.
Aitken, et al. Standards Track [Page 55]
RFC 8038 Exporting MIB Variables with IPFIX May 2017
Figure 33 shows the exported Options Template Set.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 701 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0|Scope 1=mibObjectValueInteger|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field 1 Length = 1 |0|Scope 2=mibObjectValueInteger|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field 1 Length = 2 |0| IE = mibObjectValueCounter |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 33: Example of an Options Template for an Indexed MIB Object
with Two Index Objects
Figure 34 shows the exported MIB Field Options Template used to
export the required mibObjectValue Information Element metadata.
This example of the MIB Field Options Template includes the
mibIndexIndicator to indicate that some of the other fields in the
Data Records are index objects.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 702 | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibIndexIndicator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 1 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 34: Example of a MIB Field Options Template for an Indexed
MIB Object with Two Index Objects
Aitken, et al. Standards Track [Page 56]
RFC 8038 Exporting MIB Variables with IPFIX May 2017
Figure 35 shows the exported MIB Field Options Data used to export
the required mibObjectValue Information Element metadata. Note that
the first two Data Records have all their mibIndexIndicator bits set
to 0. The third mibIndexIndicator has the value "00000011" to show
that the first two fields in the Data Record are the INDEXes for this
columnar object.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 702 | Length = 58 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 701 | informationElementIndex = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Index 00000000 | VLEN = 12 | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| "1.3.6.1.2.1.4.31.3.1.1" ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 060A2B06010201041F030101 ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | templateId = 701 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex = 1 |Index 00000000 | VLEN = 12 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibObjectIdentifier = "1.3.6.1.2.1.4.31.3.1.2" ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 060A2B06010201041F030102 ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 701 | informationElementIndex = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Index 00000011 | VLEN = 12 | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| "1.3.6.1.2.1.4.31.3.1.12" ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 060A2B06010201041F03010C ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 35: Example of a MIB Field Options Data Set for an Indexed
MIB Object with Two Index Objects
Aitken, et al. Standards Track [Page 57]
RFC 8038 Exporting MIB Variables with IPFIX May 2017
Figure 36 shows the Data Records that export the values of the three
mibObjectValue Information Elements.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 701 | Length = 18 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ipVer = 1 | ifIndex = 10 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| InForwDatagrams = 10000 | ipVer = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ifIndex = 10 | InForwDatagrams = 20000 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 36: Example of a MIB Data Set for an Indexed MIB Object
with Two Index Objects
6.6. Exporting a Columnar Object Indexed by Information Elements:
ifOutQLen
If a Packet Sampling (PSAMP) Packet Report [RFC5476] was generated on
any dropped packets on an interface, then it may be desirable to know
if the send queue on the output interface was full. This could be
done by exporting the size of the send queue (ifOutQLen) in the same
Data Record as the PSAMP Packet Report.
The exported data looks like:
+-----------+-----------+---------+--------------+------------------+
| SRC ADDR | DST ADDR | PKT LEN | OUTPUT | OUTPUT QUEUE LEN |
| | | | INTERFACE | (ifOutQLen) |
+-----------+-----------+---------+--------------+------------------+
| 192.0.2.1 | 192.0.2.3 | 150 | Eth 1/0 (15) | 45 |
| 192.0.2.4 | 192.0.2.9 | 350 | Eth 1/0 (15) | 45 |
| 192.0.2.3 | 192.0.2.9 | 650 | Eth 1/0 (15) | 23 |
| 192.0.2.4 | 192.0.2.6 | 350 | Eth 1/1 (16) | 0 |
+-----------+-----------+---------+--------------+------------------+
Table 8: Packet Report with Interface Output Queue Length
(ifOutQLen) Data
The ifOutQLen MIB object, defined in the IF-MIB [RFC2863], provides
the length of the output packet queue. This columnar object is part
of the ifEntry conceptual row and indexed by the interface index
(ifIndex).
Aitken, et al. Standards Track [Page 58]
RFC 8038 Exporting MIB Variables with IPFIX May 2017
This relationship between the ifOutQLen field and the index field is
exported using mibIndexIndicator in the MIB Field Options Template.
The value of "00001000" flags the index fields concisely.
The Template Record for the example Data Record contains the
following Information Elements:
1. sourceIPv4Address
2. destinationIPv4Address
3. totalLengthIPv4
4. egressInterface
5. ifOutQLen (indexed by egressInterface)
Figure 37 shows the exported Template Set detailing the Template for
exporting a PSAMP Report with ifOutQLen. Figures 38 and 39 show the
MIB Field Options Template and Data Record.
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 28 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 703 | Field Count = 5 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = sourceIPv4Address | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = destinationIPv4Address | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = totalLengthIPv4 | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = egressInterface | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueGauge | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 37: Example of Template for a PSAMP Report with ifOutQLen
Indexed by egressInterface
Aitken, et al. Standards Track [Page 59]
RFC 8038 Exporting MIB Variables with IPFIX May 2017
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 704 | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibIndexIndicator |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 1 |0| IE = mibObjectIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 38: Example of MIB Field Options Template for a PSAMP Report
with ifOutQLen Indexed by egressInterface
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 704 | Length = 21 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 703 | informationElementIndex = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Index 00001000 | VLEN = 11 | mibObjectIdentifier ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| "1.3.6.1.2.1.2.2.1.21" ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 06092B0601020102020115 ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| |
+-+-+-+-+-+-+-+-+
Figure 39: Example of MIB Field Options Data Record for a PSAMP
Report with ifOutQLen Indexed by egressInterface
The corresponding IPFIX Data Record is shown in Figure 40. For the
sake of the example, the interface index of "Eth 1/0" is 15 and the
interface index of "Eth 1/1" is 16.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 703 | Length = 84 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 150 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 15 (Eth 1/0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 45 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.9 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 350 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 15 (Eth 1/0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 45 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.9 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 650 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 15 (Eth 1/0) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 23 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 192.0.2.6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 350 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 16 (Eth 1/1) |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 40: Example of PSAMP Packet Report with ifOutQLen
Indexed by egressInterface
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6.7. Exporting with Multiple Contexts: The OSPF Neighbor Row Revisited
If the context used to export the MIB objects is the default one, no
extra context fields are required. This example demonstrates how to
handle the case when the context needs to be specified. It is based
on the previous example (Section 6.3).
The OSPF details of the conceptual row that was exported per
Section 6.3 would be suitable if there were only one OSPF process
running at the Observation Point. If multiple OSPF processes are
present, then they can be differentiated by also exporting the
mibContextEngineID and mibContextName.
The following fields will be exported:
+------------------+----------------+-------------------------+-----+
| Object | ID | mibObjectValue | Len |
+------------------+----------------+-------------------------+-----+
| ospfNbrIpAddr | ospfNbrEntry 1 | mibObjectValueIPAddress | 4 |
| ospfNbrAddress- | ospfNbrEntry 2 | mibObjectValueInteger | 4 |
| -LessIndex | | | |
| ospfNbrRtrId | ospfNbrEntry 3 | mibObjectValueIPAddress | 4 |
| ospfNbrState | ospfNbrEntry 6 | mibObjectValueInteger | 1 |
+------------------+----------------+-------------------------+-----+
Table 9: OSPF Neighbor Entry Objects
The example contextEngineID matches the example from [RFC3411] for
Acme Networks: "'800002B804616263'H (enterprise 696, string "abc")".
Figure 41 shows the Templates exported to support a mibObjectValueRow
that is defined within a context. Figure 42 shows the example OID
Data for the conceptual row exported in mibObjectValueRow. These are
unchanged from the previous example (Section 6.3). Figure 43 shows
the example data for two OSPF neighbors. Although these have
identical INDEX/scope values, the context information indicates that
they come from different OSPF processes. Note that the OID for
ospfNbrEntry has been encoded using ASN.1/BER to
"06082B060102010E0A01" at 10 octets long.
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 2 | Length = 20 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 800 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibContextEngineID | Field Length = 8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibContextName | Field Length = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectValueRow | Field Length = 16 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 26 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 801 | Field Count = 4 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = mibObjectValueIPAddress|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |0| IE = mibObjectValueIPAddress|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 4 |0| IE = mibObjectValueInteger |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Length = 22 | Template ID = 802 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Count = 3 | Scope Field Count = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = templateId | Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = informationElementIndex| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|0| IE = mibObjectIdentifier | Field Length = 65535 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 3 | Length = 22 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 803 | Field Count = 3 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Scope Field Count = 2 |0| IE = templateId |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = informationElementIndex|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |0| IE = mibSubIdentifier |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Field Length = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 41: Example of ospfNbrEntry Template and Options Template Sets
with Context
0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 802 | Length = 20 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Template ID = 800 | informationElementIndex = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| VLEN = 10 | mibObjectIdentifier = "1.3.6.1.2.1.14.10.1" |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| 06082B060102010E0A01 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| | Padding = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 803 | Length = 28 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 801 | informationElementIndex = 0 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier = 1 | templateId = 801 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex = 1 | mibSubIdentifier = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| templateId = 801 | informationElementIndex = 2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibSubIdentifier = 3 | templateId = 801 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| informationElementIndex = 3 | mibSubIdentifier = 6 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 42: Example of ospfNbrEntry OID Data Export with Context
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0 1 2 3
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| Set ID = 800 | Length = 60 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibContextEngineID = 800002B804616263 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... mibContextEngineID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibContextName = con1 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 801 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrIpAddr = 192.0.2.1 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrAddressLessIndex = 0 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrRtrId = 1.1.1.1 |ospfNbrState=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibContextEngineID = 800002B804616263 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ... mibContextEngineID |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| mibContextName = con2 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|Semantic=0xFF | Template ID = 801 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrIpAddr = 192.0.2.2 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrAddressLessIndex = 0 | ... |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
| ospfNbrRtrId = 2.2.2.2 |ospfNbrState=8 |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 43: Example of Data Export for ospfNbrEntry with Context
7. Configuration Considerations
When configuring a MIB OID for export, consideration should be given
to whether the SNMP context should also be configurable. If a
non-default context is used, then it should be associated with the
fields as per Section 5.6.
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8. The Collecting Process's Side
The specifications in Section 9 of [RFC7011] also apply to Collectors
that implement this specification. In addition, the following
specifications should be noted:
o A Collecting Process that implements this specification MUST store
the Data Records containing the OID object type definitions with
the same retention policy as Templates.
o A Collecting Process that implements this specification SHOULD
have access to MIB modules in order to look up the received MIB
Object Identifiers and find the full type definition and name of
MIB OID fields used in received Templates.
o It should be noted that, because reduced-size encoding MAY be used
by the Exporting Process, the Collecting Process cannot assume
that a received size for a field is the maximum size it should
expect for that field.
o If a Collecting Process receives a MIB Object Identifier that it
cannot decode, it MAY log a warning.
o A Collecting Process MUST support the three options for handling
columnar objects detailed in Section 5.8.
9. Applicability
Making available the many and varied items from MIB modules opens up
a wide range of possible applications for the IPFIX protocol, some
quite different from the usual Flow information.
Some monitoring applications periodically export a mapping of
interface ID to interface name using IPFIX Options Templates. This
could be expanded to include the ifInUcastPkts MIB object as defined
in the IF-MIB [RFC2863], indexed using the ingressInterface
Information Element. This would provide the input statistics for
each interface; these statistics can be compared to the Flow
information to ensure that the sampling rate is as expected, or, in
the absence of sampling, to ensure that all expected packets are
being monitored.
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10. Security Considerations
For this extension to the IPFIX protocol, the same security
considerations as those for the IPFIX protocol apply [RFC7011].
If the Exporter is generating or capturing the field values itself,
e.g., using the MIB objects only as an encoding or type mechanism,
there are no extra security considerations beyond standard IPFIX.
However, if the Exporter is implemented as an SNMP manager accessing
an SNMP agent, it MUST authenticate itself to the SNMP agent
[RFC3414] [RFC5591] [RFC5592] [RFC6353], and the SNMP agent MUST
enforce SNMP access control rules [RFC3415] as required by the SNMP
architecture [RFC3411].
Access to particular MIB objects is controlled by the configuration
of the IPFIX Exporter. This is consistent with the way IPFIX
controls access to other Information Elements in general.
The configuration of an IPFIX Exporter determines which MIB objects
are included in IPFIX Data Records sent to certain Collectors.
Network operators should take care that the only MIB objects that are
included in IPFIX Data Records are objects that the receiving
Collector is allowed to receive. Note that multiple users may have
access to the data from the Collector.
When exporting MIB objects that may be considered sensitive or
vulnerable in some network environments (as mentioned in the Security
Considerations section of the RFC containing the MIB module), the
Exporter should consider using anonymization techniques per [RFC6235]
if the information is anonymizable. Consumers of exported data
should therefore be able to handle the kinds of data modifications
that are described in [RFC6235].
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11. IANA Considerations
11.1. New IPFIX Semantics
New IPFIX semantics have been allocated in IANA's IPFIX registry
[IANA-IPFIX] per Section 6 of [RFC7012], as defined in the
subsections below.
11.1.1. snmpCounter
An integral value reporting the value of a counter, identical to the
Counter32 and Counter64 semantics in [RFC2578], as determined by the
Field Length.
This is similar to IPFIX's totalCounter semantic, except that total
counters have an initial value of 0 but SNMP counters do not.
IANA has assigned value 7 to snmpCounter.
11.1.2. snmpGauge
An integral value identical to the Gauge32 semantic in [RFC2578] and
the Gauge64 semantic in [RFC2856], as determined by the Field Length.
IANA has assigned value 8 to snmpGauge.
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11.2. New IPFIX Information Elements
The new Information Elements in Table 10 have been allocated in
IANA's IPFIX registry [IANA-IPFIX], as defined in the subsections
below.
In each case, the "Units" and "Range" have been left blank, since
these are not applicable.
+-----------+---------------------------+
| ElementId | Name |
+-----------+---------------------------+
| 434 | mibObjectValueInteger |
| 435 | mibObjectValueOctetString |
| 436 | mibObjectValueOID |
| 437 | mibObjectValueBits |
| 438 | mibObjectValueIPAddress |
| 439 | mibObjectValueCounter |
| 440 | mibObjectValueGauge |
| 441 | mibObjectValueTimeTicks |
| 442 | mibObjectValueUnsigned |
| 443 | mibObjectValueTable |
| 444 | mibObjectValueRow |
| 445 | mibObjectIdentifier |
| 446 | mibSubIdentifier |
| 447 | mibIndexIndicator |
| 448 | mibCaptureTimeSemantics |
| 449 | mibContextEngineID |
| 450 | mibContextName |
| 451 | mibObjectName |
| 452 | mibObjectDescription |
| 453 | mibObjectSyntax |
| 454 | mibModuleName |
+-----------+---------------------------+
Table 10: New Information Elements
11.2.1. New MIB Object Value Information Elements
11.2.1.1. mibObjectValueInteger
A new Information Element "mibObjectValueInteger" has been allocated
in IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that the
integer value of a MIB object will be exported. The MIB Object
Identifier ("mibObjectIdentifier") for this field MUST be exported
in a MIB Field Option or via another means. This Information
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Element is used for MIB objects with the Base syntax of Integer32
and INTEGER with IPFIX reduced-size encoding used as required.
The value is encoded as per the standard IPFIX Abstract Data Type
of signed32.
Abstract Data Type: signed32
Data Type Semantics: quantity
ElementId: 434
Status: current
Reference: RFC 8038
11.2.1.2. mibObjectValueOctetString
A new Information Element "mibObjectValueOctetString" has been
allocated in IANA's IPFIX registry [IANA-IPFIX], with the following
definition:
Description: An IPFIX Information Element that denotes that an
Octet String or Opaque value of a MIB object will be exported.
The MIB Object Identifier ("mibObjectIdentifier") for this field
MUST be exported in a MIB Field Option or via another means. This
Information Element is used for MIB objects with the Base syntax
of OCTET STRING and Opaque. The value is encoded as per the
standard IPFIX Abstract Data Type of octetArray.
Abstract Data Type: octetArray
Data Type Semantics: default
ElementId: 435
Status: current
Reference: RFC 8038
11.2.1.3. mibObjectValueOID
A new Information Element "mibObjectValueOID" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that an
Object Identifier or OID value of a MIB object will be exported.
The MIB Object Identifier ("mibObjectIdentifier") for this field
MUST be exported in a MIB Field Option or via another means. This
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Information Element is used for MIB objects with the Base syntax
of OBJECT IDENTIFIER. Note: In this case, the
"mibObjectIdentifier" defines which MIB object is being exported,
and the "mibObjectValueOID" field will contain the OID value of
that MIB object. The mibObjectValueOID Information Element is
encoded as ASN.1/BER [X.690] in an octetArray.
Abstract Data Type: octetArray
Data Type Semantics: default
ElementId: 436
Status: current
Reference: RFC 8038
11.2.1.4. mibObjectValueBits
A new Information Element "mibObjectValueBits" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that a set
of Enumerated flags or bits from a MIB object will be exported.
The MIB Object Identifier ("mibObjectIdentifier") for this field
MUST be exported in a MIB Field Option or via another means. This
Information Element is used for MIB objects with the Base syntax
of BITS. The flags or bits are encoded as per the standard IPFIX
Abstract Data Type of octetArray, with sufficient length to
accommodate the required number of bits. If the number of bits is
not an integer multiple of octets, then the most significant bits
at the end of the octetArray MUST be set to 0.
Abstract Data Type: octetArray
Data Type Semantics: flags
ElementId: 437
Status: current
Reference: RFC 8038
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11.2.1.5. mibObjectValueIPAddress
A new Information Element "mibObjectValueIPAddress" has been
allocated in IANA's IPFIX registry [IANA-IPFIX], with the following
definition:
Description: An IPFIX Information Element that denotes that the
IPv4 address value of a MIB object will be exported. The MIB
Object Identifier ("mibObjectIdentifier") for this field MUST be
exported in a MIB Field Option or via another means. This
Information Element is used for MIB objects with the Base syntax
of IpAddress. The value is encoded as per the standard IPFIX
Abstract Data Type of ipv4Address.
Abstract Data Type: ipv4Address
Data Type Semantics: default
ElementId: 438
Status: current
Reference: RFC 8038
11.2.1.6. mibObjectValueCounter
A new Information Element "mibObjectValueCounter" has been allocated
in IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that the
counter value of a MIB object will be exported. The MIB Object
Identifier ("mibObjectIdentifier") for this field MUST be exported
in a MIB Field Option or via another means. This Information
Element is used for MIB objects with the Base syntax of Counter32
or Counter64 with IPFIX reduced-size encoding used as required.
The value is encoded as per the standard IPFIX Abstract Data Type
of unsigned64.
Abstract Data Type: unsigned64
Data Type Semantics: snmpCounter
ElementId: 439
Status: current
Reference: RFC 8038
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11.2.1.7. mibObjectValueGauge
A new Information Element "mibObjectValueGauge" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that the
Gauge value of a MIB object will be exported. The MIB Object
Identifier ("mibObjectIdentifier") for this field MUST be exported
in a MIB Field Option or via another means. This Information
Element is used for MIB objects with the Base syntax of Gauge32.
The value is encoded as per the standard IPFIX Abstract Data Type
of unsigned32. This value represents a non-negative integer that
may increase or decrease but that shall never exceed a maximum
value or fall below a minimum value.
Abstract Data Type: unsigned32
Data Type Semantics: snmpGauge
ElementId: 440
Status: current
Reference: RFC 8038
11.2.1.8. mibObjectValueTimeTicks
A new Information Element "mibObjectValueTimeTicks" has been
allocated in IANA's IPFIX registry [IANA-IPFIX], with the following
definition:
Description: An IPFIX Information Element that denotes that the
TimeTicks value of a MIB object will be exported. The MIB Object
Identifier ("mibObjectIdentifier") for this field MUST be exported
in a MIB Field Option or via another means. This Information
Element is used for MIB objects with the Base syntax of TimeTicks.
The value is encoded as per the standard IPFIX Abstract Data Type
of unsigned32.
Abstract Data Type: unsigned32
Data Type Semantics: quantity
ElementId: 441
Status: current
Reference: RFC 8038
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11.2.1.9. mibObjectValueUnsigned
A new Information Element "mibObjectValueUnsigned" has been allocated
in IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that an
unsigned integer value of a MIB object will be exported. The MIB
Object Identifier ("mibObjectIdentifier") for this field MUST be
exported in a MIB Field Option or via another means. This
Information Element is used for MIB objects with the Base syntax
of unsigned32 with IPFIX reduced-size encoding used as required.
The value is encoded as per the standard IPFIX Abstract Data Type
of unsigned32.
Abstract Data Type: unsigned32
Data Type Semantics: quantity
ElementId: 442
Status: current
Reference: RFC 8038
11.2.1.10. mibObjectValueTable
A new Information Element "mibObjectValueTable" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that a
complete or partial conceptual table will be exported. The MIB
Object Identifier ("mibObjectIdentifier") for this field MUST be
exported in a MIB Field Option or via another means. This
Information Element is used for MIB objects with a syntax of
SEQUENCE OF. This is encoded as a subTemplateList of
mibObjectValue Information Elements. The Template specified in
the subTemplateList MUST be an Options Template and MUST include
all the objects listed in the INDEX clause as Scope Fields.
Abstract Data Type: subTemplateList
Data Type Semantics: list
ElementId: 443
Status: current
Reference: RFC 8038
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11.2.1.11. mibObjectValueRow
A new Information Element "mibObjectValueRow" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that a
single row of a conceptual table will be exported. The MIB Object
Identifier ("mibObjectIdentifier") for this field MUST be exported
in a MIB Field Option or via another means. This Information
Element is used for MIB objects with a syntax of SEQUENCE. This
is encoded as a subTemplateList of mibObjectValue Information
Elements. The subTemplateList exported MUST contain exactly one
row (i.e., one instance of the subTemplate). The Template
specified in the subTemplateList MUST be an Options Template and
MUST include all the objects listed in the INDEX clause as Scope
Fields.
Abstract Data Type: subTemplateList
Data Type Semantics: list
ElementId: 444
Status: current
Reference: RFC 8038
11.2.2. New MIB Field Options Information Elements
11.2.2.1. mibObjectIdentifier
A new Information Element "mibObjectIdentifier" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An IPFIX Information Element that denotes that a MIB
Object Identifier (MIB OID) is exported in the (Options)
Template Record. The mibObjectIdentifier Information Element
contains the OID assigned to the MIB object type definition
encoded as ASN.1/BER [X.690].
Abstract Data Type: octetArray
Data Type Semantics: default
ElementId: 445
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Status: current
Reference: RFC 8038
11.2.2.2. mibSubIdentifier
A new Information Element "mibSubIdentifier" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: A non-negative sub-identifier of an Object Identifier
(OID).
Abstract Data Type: unsigned32
Data Type Semantics: identifier
ElementId: 446
Status: current
Reference: RFC 8038
11.2.2.3. mibIndexIndicator
A new Information Element "mibIndexIndicator" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: A set of bit fields that is used for marking the
Information Elements of a Data Record that serve as INDEX MIB
objects for an indexed columnar MIB object. Each bit represents
an Information Element in the Data Record, with the n-th least
significant bit representing the n-th Information Element. A bit
set to 1 indicates that the corresponding Information Element is
an index of the columnar object represented by the mibObjectValue.
A bit set to 0 indicates that this is not the case.
If the Data Record contains more than 64 Information Elements, the
corresponding Template SHOULD be designed such that all index
fields are among the first 64 Information Elements, because the
mibIndexIndicator only contains 64 bits. If the Data Record
contains less than 64 Information Elements, then the extra bits in
the mibIndexIndicator for which no corresponding Information
Element exists MUST have the value 0 and must be disregarded by
the Collector. This Information Element may be exported with
IPFIX reduced-size encoding.
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Abstract Data Type: unsigned64
Data Type Semantics: flags
ElementId: 447
Status: current
Reference: RFC 8038
11.2.2.4. mibCaptureTimeSemantics
A new Information Element "mibCaptureTimeSemantics" has been
allocated in IANA's IPFIX registry [IANA-IPFIX], with the following
definition:
Description: Indicates when in the lifetime of the Flow the MIB
value was retrieved from the MIB for a mibObjectIdentifier. This
is used to indicate if the value exported was collected from the
MIB closer to Flow creation or Flow export time and refers to the
Timestamp fields included in the same Data Record. This field
SHOULD be used when exporting a mibObjectValue that specifies
counters or statistics.
If the MIB value was sampled by SNMP prior to the IPFIX Metering
Process or Exporting Process retrieving the value (i.e., the data
is already stale) and it is important to know the exact sampling
time, then an additional observationTime* element should be paired
with the OID using IPFIX Structured Data [RFC6313]. Similarly, if
different MIB capture times apply to different mibObjectValue
elements within the Data Record, then individual
mibCaptureTimeSemantics Information Elements should be paired with
each OID using IPFIX Structured Data.
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Values:
0 undefined
1 begin - The value for the MIB object is captured from the
MIB when the Flow is first observed
2 end - The value for the MIB object is captured from the MIB
when the Flow ends
3 export - The value for the MIB object is captured from the
MIB at export time
4 average - The value for the MIB object is an average of
multiple captures from the MIB over the observed life of
the Flow
Abstract Data Type: unsigned8
Data Type Semantics: identifier
ElementId: 448
Status: current
Reference: RFC 8038
11.2.2.5. mibContextEngineID
A new Information Element "mibContextEngineID" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: A mibContextEngineID that specifies the SNMP
engine ID for a MIB field being exported over IPFIX. Definition
as per [RFC3411], Section 3.3.
Abstract Data Type: octetArray
Data Type Semantics: default
ElementId: 449
Status: current
Reference: RFC 8038
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11.2.2.6. mibContextName
A new Information Element "mibContextName" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: An Information Element that denotes that a MIB
context name is specified for a MIB field being exported over
IPFIX. Reference [RFC3411], Section 3.3.
Abstract Data Type: string
Data Type Semantics: default
ElementId: 450
Status: current
Reference: RFC 8038
11.2.3. New MIB Type Information Elements
11.2.3.1. mibObjectName
A new Information Element "mibObjectName" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: The name (called a descriptor in [RFC2578]) of an
object type definition.
Abstract Data Type: string
Data Type Semantics: default
ElementId: 451
Status: current
Reference: RFC 8038
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11.2.3.2. mibObjectDescription
A new Information Element "mibObjectDescription" has been allocated
in IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: The value of the DESCRIPTION clause of a MIB object
type definition.
Abstract Data Type: string
Data Type Semantics: default
ElementId: 452
Status: current
Reference: RFC 8038
11.2.3.3. mibObjectSyntax
A new Information Element "mibObjectSyntax" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: The value of the SYNTAX clause of a MIB object type
definition, which may include a textual convention or sub-typing.
See [RFC2578].
Abstract Data Type: string
Data Type Semantics: default
ElementId: 453
Status: current
Reference: RFC 8038
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11.2.3.4. mibModuleName
A new Information Element "mibModuleName" has been allocated in
IANA's IPFIX registry [IANA-IPFIX], with the following definition:
Description: The textual name of the MIB module that defines a MIB
object.
Abstract Data Type: string
Data Type Semantics: default
ElementId: 454
Status: current
Reference: RFC 8038
12. References
12.1. Normative References
[IANA-IPFIX]
IANA, "IP Flow Information Export (IPFIX) Entities",
<http://www.iana.org/assignments/ipfix/>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC2578] McCloghrie, K., Ed., Perkins, D., Ed., and J.
Schoenwaelder, Ed., "Structure of Management Information
Version 2 (SMIv2)", STD 58, RFC 2578,
DOI 10.17487/RFC2578, April 1999,
<http://www.rfc-editor.org/info/rfc2578>.
[RFC2856] Bierman, A., McCloghrie, K., and R. Presuhn, "Textual
Conventions for Additional High Capacity Data Types",
RFC 2856, DOI 10.17487/RFC2856, June 2000,
<http://www.rfc-editor.org/info/rfc2856>.
[RFC3411] Harrington, D., Presuhn, R., and B. Wijnen, "An
Architecture for Describing Simple Network Management
Protocol (SNMP) Management Frameworks", STD 62, RFC 3411,
DOI 10.17487/RFC3411, December 2002,
<http://www.rfc-editor.org/info/rfc3411>.
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[RFC6526] Claise, B., Aitken, P., Johnson, A., and G. Muenz,
"IP Flow Information Export (IPFIX) Per Stream Control
Transmission Protocol (SCTP) Stream", RFC 6526,
DOI 10.17487/RFC6526, March 2012,
<http://www.rfc-editor.org/info/rfc6526>.
[RFC7011] Claise, B., Ed., Trammell, B., Ed., and P. Aitken,
"Specification of the IP Flow Information Export (IPFIX)
Protocol for the Exchange of Flow Information", STD 77,
RFC 7011, DOI 10.17487/RFC7011, September 2013,
<http://www.rfc-editor.org/info/rfc7011>.
[RFC7012] Claise, B., Ed., and B. Trammell, Ed., "Information Model
for IP Flow Information Export (IPFIX)", RFC 7012,
DOI 10.17487/RFC7012, September 2013,
<http://www.rfc-editor.org/info/rfc7012>.
[X.690] International Telecommunication Union, "Information
Technology - ASN.1 encoding rules: Specification of Basic
Encoding Rules (BER), Canonical Encoding Rules (CER) and
Distinguished Encoding Rules (DER)", ITU-T Recommendation
X.690, ISO/IEC 8825-1, August 2015,
<https://www.itu.int/rec/T-REC-X.690>.
12.2. Informative References
[CISCO-PROCESS-MIB]
Cisco Systems Inc., "CISCO-PROCESS-MIB.my: MIB for CPU and
process statistics", <ftp://ftp.cisco.com/pub/mibs/v2/
CISCO-PROCESS-MIB.my>.
[RFC2863] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB", RFC 2863, DOI 10.17487/RFC2863, June 2000,
<http://www.rfc-editor.org/info/rfc2863>.
[RFC2982] Kavasseri, R., Ed., "Distributed Management Expression
MIB", RFC 2982, DOI 10.17487/RFC2982, October 2000,
<http://www.rfc-editor.org/info/rfc2982>.
[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,
DOI 10.17487/RFC3414, December 2002,
<http://www.rfc-editor.org/info/rfc3414>.
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[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,
DOI 10.17487/RFC3415, December 2002,
<http://www.rfc-editor.org/info/rfc3415>.
[RFC3444] Pras, A. and J. Schoenwaelder, "On the Difference between
Information Models and Data Models", RFC 3444,
DOI 10.17487/RFC3444, January 2003,
<http://www.rfc-editor.org/info/rfc3444>.
[RFC4022] Raghunarayan, R., Ed., "Management Information Base for
the Transmission Control Protocol (TCP)", RFC 4022,
DOI 10.17487/RFC4022, March 2005,
<http://www.rfc-editor.org/info/rfc4022>.
[RFC4293] Routhier, S., Ed., "Management Information Base for the
Internet Protocol (IP)", RFC 4293, DOI 10.17487/RFC4293,
April 2006, <http://www.rfc-editor.org/info/rfc4293>.
[RFC4750] Joyal, D., Ed., Galecki, P., Ed., Giacalone, S., Ed.,
Coltun, R., and F. Baker, "OSPF Version 2 Management
Information Base", RFC 4750, DOI 10.17487/RFC4750,
December 2006, <http://www.rfc-editor.org/info/rfc4750>.
[RFC4960] Stewart, R., Ed., "Stream Control Transmission Protocol",
RFC 4960, DOI 10.17487/RFC4960, September 2007,
<http://www.rfc-editor.org/info/rfc4960>.
[RFC5102] Quittek, J., Bryant, S., Claise, B., Aitken, P., and J.
Meyer, "Information Model for IP Flow Information Export",
RFC 5102, DOI 10.17487/RFC5102, January 2008,
<http://www.rfc-editor.org/info/rfc5102>.
[RFC5476] Claise, B., Ed., Johnson, A., and J. Quittek, "Packet
Sampling (PSAMP) Protocol Specifications", RFC 5476,
DOI 10.17487/RFC5476, March 2009,
<http://www.rfc-editor.org/info/rfc5476>.
[RFC5591] Harrington, D. and W. Hardaker, "Transport Security Model
for the Simple Network Management Protocol (SNMP)",
STD 78, RFC 5591, DOI 10.17487/RFC5591, June 2009,
<http://www.rfc-editor.org/info/rfc5591>.
[RFC5592] Harrington, D., Salowey, J., and W. Hardaker, "Secure
Shell Transport Model for the Simple Network Management
Protocol (SNMP)", RFC 5592, DOI 10.17487/RFC5592,
June 2009, <http://www.rfc-editor.org/info/rfc5592>.
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[RFC6235] Boschi, E. and B. Trammell, "IP Flow Anonymization
Support", RFC 6235, DOI 10.17487/RFC6235, May 2011,
<http://www.rfc-editor.org/info/rfc6235>.
[RFC6313] Claise, B., Dhandapani, G., Aitken, P., and S. Yates,
"Export of Structured Data in IP Flow Information Export
(IPFIX)", RFC 6313, DOI 10.17487/RFC6313, July 2011,
<http://www.rfc-editor.org/info/rfc6313>.
[RFC6353] Hardaker, W., "Transport Layer Security (TLS) Transport
Model for the Simple Network Management Protocol (SNMP)",
STD 78, RFC 6353, DOI 10.17487/RFC6353, July 2011,
<http://www.rfc-editor.org/info/rfc6353>.
Acknowledgments
The authors would like to thank Andrew Johnson for his collaboration
on the first draft version of this document, and to thank Andrew
Feren and Brian Trammell for their detailed reviews.
Juergen Schoenwaelder was partly funded by Flamingo, a Network of
Excellence project (ICT-318488) supported by the European Commission
under its Seventh Framework Programme.
Authors' Addresses
Paul Aitken (editor)
Brocade Communications Systems, Inc.
19a Canning Street, Level 3
Edinburgh, Scotland EH3 8EG
United Kingdom
Phone: +44 203 005 0731
Email: paitken@brocade.com
Benoit Claise
Cisco Systems, Inc.
De Kleetlaan 6a b1
Diegem 1813
Belgium
Phone: +32 2 704 5622
Email: bclaise@cisco.com
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Srikar B S
Mojo Networks, Inc.
S. No. 7, Pinnac House II
Kothrud, Pune 411038
India
Phone: +91 94 4847 6672
Email: srikarbs@gmail.com
Colin McDowall
Brocade Communications Systems, Inc.
19a Canning Street, Level 3
Edinburgh, Scotland EH3 8EG
United Kingdom
Phone: +44 203 005 0687
Email: cmcdowal@brocade.com
Juergen Schoenwaelder
Jacobs University Bremen
Campus Ring 1
Bremen 28725
Germany
Phone: +49 421 200 3587
Email: j.schoenwaelder@jacobs-university.de
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