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PROPOSED STANDARD
Errata Exist
Network Working Group F. Baker
Request for Comments: 3289 Cisco System
Category: Standards Track K. Chan
Nortel Networks
A. Smith
Harbour Networks
May 2002
Management Information Base for the
Differentiated Services Architecture
Status of this Memo
This document specifies an Internet standards track protocol for the
Internet community, and requests discussion and suggestions for
improvements. Please refer to the current edition of the "Internet
Official Protocol Standards" (STD 1) for the standardization state
and status of this protocol. Distribution of this memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2002). All Rights Reserved.
Abstract
This memo describes an SMIv2 (Structure of Management Information
version 2) MIB for a device implementing the Differentiated Services
Architecture. It may be used both for monitoring and configuration
of a router or switch capable of Differentiated Services
functionality.
Table of Contents
1 The SNMP Management Framework ................................. 3
2 Relationship to other working group documents ................. 4
2.1 Relationship to the Informal Management Model for
Differentiated Services Router ............................. 4
2.2 Relationship to other MIBs and Policy Management ............ 5
3 MIB Overview .................................................. 6
3.1 Processing Path ............................................. 7
3.1.1 diffServDataPathTable - The Data Path Table ............... 7
3.2 Classifier .................................................. 7
3.2.1 diffServClfrElementTable - The Classifier Element Table ... 8
3.2.2 diffServMultiFieldClfrTable - The Multi-field Classifier
Table ...................................................... 9
3.3 Metering Traffic ............................................ 10
3.3.1 diffServMeterTable - The Meter Table ...................... 11
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3.3.2 diffServTBParamTable - The Token Bucket Parameters Table... 11
3.4 Actions applied to packets .................................. 12
3.4.1 diffServActionTable - The Action Table .................... 12
3.4.2 diffServCountActTable - The Count Action Table ............ 12
3.4.3 diffServDscpMarkActTable - The Mark Action Table .......... 13
3.4.4 diffServAlgDropTable - The Algorithmic Drop Table ......... 13
3.4.5 diffServRandomDropTable - The Random Drop Parameters Table 14
3.5 Queuing and Scheduling of Packets ........................... 16
3.5.1 diffServQTable - The Class or Queue Table ................. 16
3.5.2 diffServSchedulerTable - The Scheduler Table .............. 16
3.5.3 diffServMinRateTable - The Minimum Rate Table ............. 16
3.5.4 diffServMaxRateTable - The Maximum Rate Table ............. 17
3.5.5 Using queues and schedulers together ...................... 17
3.6 Example configuration for AF and EF ......................... 20
3.6.1 AF and EF Ingress Interface Configuration ................. 20
3.6.1.1 Classification In The Example ........................... 22
3.6.1.2 AF Implementation On an Ingress Edge Interface .......... 22
3.6.1.2.1 AF Metering On an Ingress Edge Interface .............. 22
3.6.1.2.2 AF Actions On an Ingress Edge Interface ............... 23
3.6.1.3 EF Implementation On an Ingress Edge Interface .......... 23
3.6.1.3.1 EF Metering On an Ingress Edge Interface .............. 23
3.6.1.3.2 EF Actions On an Ingress Edge Interface ............... 23
3.7 AF and EF Egress Edge Interface Configuration ............... 24
3.7.1 Classification On an Egress Edge Interface ................ 24
3.7.2 AF Implementation On an Egress Edge Interface ............. 26
3.7.2.1 AF Metering On an Egress Edge Interface ................. 26
3.7.2.2 AF Actions On an Egress Edge Interface .................. 29
3.7.2.3 AF Rate-based Queuing On an Egress Edge Interface ....... 30
3.7.3 EF Implementation On an Egress Edge Interface ............. 30
3.7.3.1 EF Metering On an Egress Edge Interface ................. 30
3.7.3.2 EF Actions On an Egress Edge Interface .................. 30
3.7.3.3 EF Priority Queuing On an Egress Edge Interface ......... 32
4 Conventions used in this MIB .................................. 33
4.1 The use of RowPointer to indicate data path linkage ......... 33
4.2 The use of RowPointer to indicate parameters ................ 34
4.3 Conceptual row creation and deletion ........................ 34
5 Extending this MIB ............................................ 35
6 MIB Definition ................................................ 35
7 Acknowledgments ............................................... 110
8 Security Considerations ....................................... 110
9 Intellectual Property Rights .................................. 111
10 References ................................................... 112
11 Authors' Addresses ........................................... 115
12 Full Copyright Statement ..................................... 116
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1. The SNMP Management Framework
The SNMP Management Framework presently consists of five major
components:
o An overall architecture, described in [RFC 2571].
o Mechanisms for describing and naming objects and events for the
purpose of management. The first version of this Structure of
Management Information (SMI) is called SMIv1 and is described
in [RFC 1155], [RFC 1212] and [RFC 1215]. The second version,
called SMIv2, is described in [RFC 2578], RFC 2579 [RFC 2579]
and [RFC 2580].
o Message protocols for transferring management information. The
first version of the SNMP message protocol is called SNMPv1 and
is described in [RFC 1157]. A second version of the SNMP
message protocol, which is not an Internet standards track
protocol, is called SNMPv2c and is described in [RFC 1901] and
[RFC 1906]. The third version of the message protocol is
called SNMPv3 and is described in [RFC 1906], [RFC 2572] and
[RFC 2574].
o Protocol operations for accessing management information. The
first set of protocol operations and associated PDU formats is
described in [RFC 1157]. A second set of protocol operations
and associated PDU formats is described in [RFC 1905].
o A set of fundamental applications described in [RFC 2573] and
the view-based access control mechanism described in [RFC
2575].
A more detailed introduction to the current SNMP Management Framework
can be found in [RFC 2570].
Managed objects are accessed via a virtual information store, termed
the Management Information Base or MIB. Objects in the MIB are
defined using the mechanisms defined in the SMI.
This memo specifies a MIB module that is compliant to the SMIv2. A
MIB conforming to the SMIv1 can be produced through the appropriate
translations. The resulting translated MIB must be semantically
equivalent, except where objects or events are omitted because there
is no translation is possible (use of Counter64). Some machine-
readable information in SMIv2 will be converted into textual
descriptions in SMIv1 during the translation process. However, this
loss of machine readable information is not considered to change the
semantics of the MIB.
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The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC 2119].
2. Relationship to other working group documents
The Differentiated Services Working Group and related working groups
developed other documents, notably the Informal Management Model and
the policy configuration paradigm of SNMPCONF. The relationship
between the MIB and those documents is clarified here.
2.1. Relationship to the Informal Management Model for Differentiated
Services Router
This MIB is similar in design to [MODEL], although it can be used to
build functional data paths that the model would not well describe.
The model conceptually describes ingress and egress interfaces of an
n-port router, which may find some interfaces at a network edge and
others facing into the network core. It describes the configuration
and management of a Differentiated Services interface in terms of one
or more Traffic Conditioning Blocks (TCB), each containing, arranged
in the specified order, by definition, zero or more classifiers,
meters, actions, algorithmic droppers, queues and schedulers.
Traffic may be classified, and classified traffic may be metered.
Each stream of traffic identified by a combination of classifiers and
meters may have some set of actions performed on it; it may have
dropping algorithms applied and it may ultimately be stored into a
queue before being scheduled out to its next destination, either onto
a link or to another TCB. At times, the treatment for a given packet
must have any of those elements repeated. [MODEL] models this by
cascading multiple TCBs, while this MIB describes the policy by
directly linking the functional data path elements.
The MIB represents this cascade by following the "Next" attributes of
the various elements. They indicate what the next step in
Differentiated Services processing will be, whether it be a
classifier, meter, action, algorithmic dropper, queue, scheduler or a
decision to now forward a packet.
The higher level concept of a TCB is not required in the
parameterization or in the linking together of the individual
elements, hence it is not used in the MIB itself and is only
mentioned in the text for relating the MIB with the [MODEL]. Rather,
the MIB models the individual elements that make up the TCBs.
This MIB uses the notion of a Data Path to indicate the
Differentiated Services processing a packet may experience. The Data
Path a packet will initially follow is an attribute of the interface
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in question. The Data Path Table provides a starting point for each
direction (ingress or egress) on each interface. A Data Path Table
Entry indicates the first of possible multiple elements that will
apply Differentiated Services treatment to the packet.
2.2. Relationship to other MIBs and Policy Management
This MIB provides for direct reporting and manipulation of detailed
functional elements. These elements consist of a structural element
and one or more parameter-bearing elements. While this can be
cumbersome, it allows the reuse of parameters. For example, a
service provider may offer three varieties of contracts, and
configure three parameter elements. Each such data path on the
system may then refer to these sets of parameters. The
diffServDataPathTable couples each direction on each interface with
the specified data path linkage. The concept of "interface" is as
defined by InterfaceIndex/ifIndex of the IETF Interfaces MIB [IF-
MIB].
Other MIBs and data structure definitions for policy management
mechanisms, other than SNMP/SMIv2 are likely to exist in the future
for the purpose of abstracting the model in other ways. An example
is the Differentiated Services Policy Information Base, [DSPIB].
In particular, abstractions in the direction of less detailed
definitions of Differentiated Services functionality are likely e.g.
some form of "Per-Hop Behavior"-based definition involving a template
of detailed object values which is applied to specific instances of
objects in this MIB semi-automatically.
Another possible direction of abstraction is one using a concept of
"roles" (often, but not always, applied to interfaces). In this
case, it may be possible to re-use the object definitions in this
MIB, especially the parameterization tables. The Data Path table
will help in the reuse of the data path linkage tables by having the
interface specific information centralized, allowing easier
mechanical replacement of ifIndex by some sort of "roleIndex". This
work is ongoing.
The reuse of parameter blocks on a variety of functional data paths
is intended to simplify network management. In many cases, one could
also re-use the structural elements as well; this has the unfortunate
side-effect of re-using the counters, so that monitoring information
is lost. For this reason, the re-use of structural elements is not
generally recommended.
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3. MIB Overview
The Differentiated Services Architecture does not specify how an
implementation should be assembled. The [MODEL] describes a general
approach to implementation design, or to user interface design. Its
components could, however, be assembled in a different way. For
example, traffic conforming to a meter might be run through a second
meter, or reclassified.
This MIB models the same functional data path elements, allowing the
network manager to assemble them in any fashion that meets the
relevant policy. These data path elements include Classifiers,
Meters, Actions of various sorts, Queues, and Schedulers.
In many of these tables, a distinction is drawn between the structure
of the policy (do this, then do that) and the parameters applied to
specific policy elements. This is to facilitate configuration, if
the MIB is used for that. The concept is that a set of parameters,
such as the values that describe a specific token bucket, might be
configured once and applied to many interfaces.
The RowPointer Textual Convention is therefore used in two ways in
this MIB. It is defined for the purpose of connecting an object to
an entry dynamically; the RowPointer object identifies the first
object in the target Entry, and in so doing points to the entire
entry. In this MIB, it is used as a connector between successive
functional data path elements, and as the link between the policy
structure and the parameters that are used. When used as a
connector, it says what happens "next"; what happens to classified
traffic, to traffic conforming or not conforming to a meter, and so
on. When used to indicate the parameters applied in a policy, it
says "specifically" what is meant; the structure points to the
parameters of its policy.
The use of RowPointers as connectors allows for the simple extension
of the MIB. The RowPointers, whether "next" or "specific", may point
to Entries defined in other MIB modules. For example, the only type
of meter defined in this MIB is a token bucket meter; if another type
of meter is required, another MIB could be defined describing that
type of meter, and diffServMeterSpecific could point to it.
Similarly, if a new action is required, the "next" pointer of the
previous functional datapath element could point to an Entry defined
in another MIB, public or proprietary.
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3.1. Processing Path
An interface has an ingress and an egress direction, and will
generally have a different policy in each direction. As traffic
enters an edge interface, it may be classified, metered, counted, and
marked. Traffic leaving the same interface might be remarked
according to the contract with the next network, queued to manage the
bandwidth, and so on. As [MODEL] points out, the functional datapath
elements used on ingress and egress are of the same type, but may be
structured in very different ways to implement the relevant policies.
3.1.1. diffServDataPathTable - The Data Path Table
Therefore, when traffic arrives at an ingress or egress interface,
the first step in applying the policy is determining what policy
applies. This MIB does that by providing a table of pointers to the
first functional data path element, indexed by interface and
direction on that interface. The content of the
diffServDataPathEntry is a single RowPointer, which points to that
functional data path element.
When diffServDataPathStart in a direction on an interface is
undefined or is set to zeroDotZero, the implication is that there is
no specific policy to apply.
3.2. Classifier
Classifiers are used to differentiate among types of traffic. In the
Differentiated Services architecture, one usually discusses a
behavior aggregate identified by the application of one or more
Differentiated Services Code Points (DSCPs). However, especially at
network edges (which include hosts and first hop routers serving
hosts), traffic may arrive unmarked or the marks may not be trusted.
In these cases, one applies a Multi-Field Classifier, which may
select an aggregate as coarse as "all traffic", as fine as a specific
microflow identified by IP Addresses, IP Protocol, and TCP or UDP
ports, or variety of slices in between.
Classifiers can be simple or complex. In a core interface, one would
expect to find simple behavior aggregate classification to be used.
However, in an edge interface, one might first ask what application
is being used, meter the arriving traffic, and then apply various
policies to the non-conforming traffic depending on the Autonomous
System number advertising the destination address. To accomplish
such a thing, traffic must be classified, metered, and then
reclassified. To this end, the MIB defines separate classifiers,
which may be applied at any point in processing, and may have
different content as needed.
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The MIB also allows for ambiguous classification in a structured
fashion. In the end, traffic classification must be unambiguous; one
must know for certain what policy to apply to any given packet.
However, writing an unambiguous specification is often tedious, while
writing a specification in steps that permits and excludes various
kinds of traffic may be simpler and more intuitive. In such a case,
the classification "steps" are enumerated; all classification
elements of one precedence are applied as if in parallel, and then
all classification elements of the next precedence.
This MIB defines a single classifier parameter entry, the Multi-field
Classifier. A degenerate case of this multi-field classifier is a
Behavior Aggregate classifier. Other classifiers may be defined in
other MIB modules, to select traffic from a given layer two neighbor
or a given interface, traffic whose addresses belong to a given BGP
Community or Autonomous System, and so on.
3.2.1. diffServClfrElementTable - The Classifier Element Table
A classifier consists of classifier elements. A classifier element
identifies a specific set of traffic that forms part of a behavior
aggregate; other classifier elements within the same classifier may
identify other traffic that also falls into the behavior aggregate.
For example, in identifying AF traffic for the aggregate AF1, one
might implement separate classifier elements for AF11, AF12, and AF13
within the same classifier and pointing to the same subsequent meter.
Generally, one would expect the Data Path Entry to point to a
classifier (which is to say, a set of one or more classifier
elements), although it may point to something else when appropriate.
Reclassification in a functional data path is achieved by pointing to
another Classifier Entry when appropriate.
A classifier element is a structural element, indexed by classifier
ID and element ID. It has a precedence value, allowing for
structured ambiguity as described above, a "specific" pointer that
identifies what rule is to be applied, and a "next" pointer directing
traffic matching the classifier to the next functional data path
element. If the "next" pointer is zeroDotZero, the indication is
that there is no further differentiated services processing for this
behavior aggregate. However, if the "specific" pointer is
zeroDotZero, the device is misconfigured. In such a case, the
classifier element should be operationally treated as if it were not
present.
When the MIB is used for configuration, diffServClfrNextFree and
diffServClfrElementNextFree always contain legal values for
diffServClfrId and diffServClfrElementId that are not currently used
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in the system's configuration. The values are validated when
creating diffServClfrId and diffServClfrElementId, and in the event
of a failure (which would happen if two managers simultaneously
attempted to create an entry) must be re-read.
3.2.2. diffServMultiFieldClfrTable - The Multi-field Classifier Table
This MIB defines a single parameter type for classification, the
Multi-field Classifier. As a parameter, a filter may be specified
once and applied to many interfaces, using
diffServClfrElementSpecific. This filter matches:
o IP source address prefix, including host, CIDR Prefix, and "any
source address"
o IP destination address prefix, including host, CIDR Prefix, and
"any destination address"
o IPv6 Flow ID
o IP protocol or "any"
o TCP/UDP/SCTP source port range, including "any"
o TCP/UDP/SCTP destination port range, including "any"
o Differentiated Services Code Point
Since port ranges, IP prefixes, or "any" are defined in each case, it
is clear that a wide variety of filters can be constructed. The
Differentiated Services Behavior Aggregate filter is a special case
of this filter, in which only the DSCP is specified.
Other MIB modules may define similar filters in the same way. For
example, a filter for Ethernet information might define source and
destination MAC addresses of "any", Ethernet Packet Type, IEEE 802.2
SAPs, and IEEE 802.1 priorities. A filter related to policy routing
might be structured like the diffServMultiFieldClfrTable, but contain
the BGP Communities of the source and destination prefix rather than
the prefix itself, meaning "any prefix in this community". For such
a filter, a table similar to diffServMultiFieldClfrTable is
constructed, and diffServClfrElementSpecific is configured to point
to it.
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When the MIB is used for configuration,
diffServMultiFieldClfrNextFree always contains a legal value for
diffServMultiFieldClfrId that is not currently used in the system's
configuration.
3.3. Metering Traffic
As discussed in [MODEL], a meter and a shaper are functions that
operate on opposing ends of a link. A shaper schedules traffic for
transmission at specific times in order to approximate a particular
line speed or combination of line speeds. In its simplest form, if
the traffic stream contains constant sized packets, it might transmit
one packet per unit time to build the equivalent of a CBR circuit.
However, various factors intervene to make the approximation inexact;
multiple classes of traffic may occasionally schedule their traffic
at the same time, the variable length nature of IP traffic may
introduce variation, and factors in the link or physical layer may
change traffic timing. A meter integrates the arrival rate of
traffic and determines whether the shaper at the far end was
correctly applied, or whether the behavior of the application in
question is naturally close enough to such behavior to be acceptable
under a given policy.
A common type of meter is a Token Bucket meter, such as [srTCM] or
[trTCM]. This type of meter assumes the use of a shaper at a
previous node; applications which send at a constant rate when
sending may conform if the token bucket is properly specified. It
specifies the acceptable arrival rate and quantifies the acceptable
variability, often by specifying a burst size or an interval; since
rate = quantity/time, specifying any two of those parameters implies
the third, and a large interval provides for a forgiving system.
Multiple rates may be specified, as in AF, such that a subset of the
traffic (up to one rate) is accepted with one set of guarantees, and
traffic in excess of that but below another rate has a different set
of guarantees. Other types of meters exist as well.
One use of a meter is when a service provider sells at most, a
certain bit rate to one of its customers, and wants to drop the
excess. In such a case, the fractal nature of normal Internet
traffic must be reflected in large burst intervals, as TCP frequently
sends packet pairs or larger bursts, and responds poorly when more
than one packet in a round trip interval is dropped. Applications
like FTP contain the effect by simply staying below the target bit
rate; this type of configuration very adversely affects transaction
applications like HTTP, however. Another use of a meter is in the AF
specification, in which excess traffic is marked with a related DSCP
and subjected to slightly more active queue depth management. The
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application is not sharply limited to a contracted rate in such a
case, but can be readily contained should its traffic create a
burden.
3.3.1. diffServMeterTable - The Meter Table
The Meter Table is a structural table, specifying a specific
functional data path element. Its entry consists essentially of
three RowPointers - a "succeed" pointer, for traffic conforming to
the meter, a "fail" pointer, for traffic not conforming to the meter,
and a "specific" pointer, to identify the parameters in question.
This structure is a bow to SNMP's limitations; it would be better to
have a structure with N rates and N+1 "next" pointers, with a single
algorithm specified. In this case, multiple meter entries connected
by the "fail" link are understood to contain the parameters for a
specified algorithm, and traffic conforming to a given rate follows
their "succeed" paths. Within this MIB, only Token Bucket parameters
are specified; other varieties of meters may be designed in other MIB
modules.
When the MIB is used for configuration, diffServMeterNextFree always
contains a legal value for diffServMeterId that is not currently used
in the system's configuration.
3.3.2. diffServTBParamTable - The Token Bucket Parameters Table
The Token Bucket Parameters Table is a set of parameters that define
a Token Bucket Meter. As a parameter, a token bucket may be
specified once and applied to many interfaces, using
diffServMeterSpecific. Specifically, several modes of [srTCM] and
[trTCM] are addressed. Other varieties of meters may be specified in
other MIB modules.
In general, if a Token Bucket has N rates, it has N+1 potential
outcomes - the traffic stream is slower than and therefore conforms
to all of the rates, it fails the first few but is slower than and
therefore conforms to the higher rates, or it fails all of them. As
such, multi-rate meters should specify those rates in monotonically
increasing order, passing through the diffServMeterFailNext from more
committed to more excess rates, and finally falling through
diffServMeterFailNext to the set of actions that apply to traffic
which conforms to none of the specified rates. diffServTBParamType
in the first entry indicates the algorithm being used. At each rate,
diffServTBParamRate is derivable from diffServTBParamBurstSize and
diffServTBParamInterval; a superior implementation will allow the
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configuration of any two of diffServTBParamRate,
diffServTBParamBurstSize, and diffServTBParamInterval, and respond
with the appropriate error code if all three are specified but are
not mathematically related.
When the MIB is used for configuration, diffServTBParamNextFree
always contains a legal value for diffServTBParamId that is not
currently used in the system's configuration.
3.4. Actions applied to packets
"Actions" are the things a differentiated services interface PHB may
do to a packet in transit. At a minimum, such a policy might
calculate statistics on traffic in various configured classes, mark
it with a DSCP, drop it, or enqueue it before passing it on for other
processing.
Actions are composed of a structural element, the
diffServActionTable, and various component action entries that may be
applied. In the case of the Algorithmic Dropper, an additional
parameter table may be specified to control Active Queue Management,
as defined in [RED93] and other AQM specifications.
3.4.1. diffServActionTable - The Action Table
The action table identifies sequences of actions to be applied to a
packet. Successive actions are chained through diffServActionNext,
ultimately resulting in zeroDotZero (indicating that the policy is
complete), a pointer to a queue, or a pointer to some other
functional data path element.
When the MIB is used for configuration, diffServActionNextFree always
contains a legal value for diffServActionId that is not currently
used in the system's configuration.
3.4.2. diffServCountActTable - The Count Action Table
The count action accumulates statistics pertaining to traffic passing
through a given path through the policy. It is intended to be useful
for usage-based billing, for statistical studies, or for analysis of
the behavior of a policy in a given network. The objects in the
Count Action are various counters and a discontinuity time. The
counters display the number of packets and bytes encountered on the
path since the discontinuity time. They share the same discontinuity
time, which is the discontinuity time of the interface or agent.
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The designers of this MIB expect that every path through a policy
should have a corresponding counter. In early versions, it was
impossible to configure an action without implementing a counter,
although the current design makes them in effect the network
manager's option, as a result of making actions consistent in
structure and extensibility. The assurance of proper debugging and
accounting is therefore left with the policy designer.
When the MIB is used for configuration, diffServCountActNextFree
always contains a legal value for diffServCountActId that is not
currently used in the system's configuration.
3.4.3. diffServDscpMarkActTable - The Mark Action Table
The Mark Action table is an unusual table, both in SNMP and in this
MIB. It might be viewed not so much as an array of single-object
entries as an array of OBJECT-IDENTIFIER conventions, as the OID for
a diffServDscpMarkActDscp instance conveys all of the necessary
information: packets are to be marked with the requisite DSCP.
As such, contrary to common practice, the index for the table is
read- only, and is both the Entry's index and its only value.
3.4.4. diffServAlgDropTable - The Algorithmic Drop Table
The Algorithmic Drop Table identifies a dropping algorithm, drops
packets, and counts the drops. Classified as an action, it is in
effect a method which applies a packet to a queue, and may modify
either. When the algorithm is "always drop", this is simple; when
the algorithm calls for head-drop, tail-drop, or a variety of Active
Queue Management, the queue is inspected, and in the case of Active
Queue Management, additional parameters are REQUIRED.
What may not be clear from the name is that an Algorithmic Drop
action often does not drop traffic. Algorithms other than "always
drop" normally drop a few percent of packets at most. The action
inspects the diffServQEntry that diffServAlgDropQMeasure points to in
order to determine whether the packet should be dropped.
When the MIB is used for configuration, diffServAlgDropNextFree
always contains a legal value for diffServAlgDropId that is not
currently used in the system's configuration.
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3.4.5. diffServRandomDropTable - The Random Drop Parameters Table
The Random Drop Table is an extension of the Algorithmic Drop Table
intended for use on queues whose depth is actively managed. Active
Queue Management algorithms are typified by [RED93], but the
parameters they use vary. It was deemed for the purposes of this MIB
that the proper values to represent include:
o Target case mean queue depth, expressed in bytes or packets
o Worst case mean queue depth, expressed in bytes or packets
o Maximum drop rate expressed as drops per thousand
o Coefficient of an exponentially weighted moving average,
expressed as the numerator of a fraction whose denominator is
65536.
o Sampling rate
An example of the representation chosen in this MIB for this element
is shown in Figure 1.
Random droppers often have their drop probability function described
as a plot of drop probability (P) against averaged queue length (Q).
(Qmin,Pmin) then defines the start of the characteristic plot.
Normally Pmin=0, meaning with average queue length below Qmin, there
will be no drops. (Qmax,Pmax) defines a "knee" on the plot, after
which point the drop probability becomes more progressive (greater
slope). (Qclip,1) defines the queue length at which all packets will
be dropped. Notice this is different from Tail Drop because this
uses an averaged queue length, although it is possible for Qclip to
equal Qmax.
In the MIB module, diffServRandomDropMinThreshBytes and
diffServRandomDropMinThreshPkts represent Qmin.
diffServRandomDropMaxThreshBytes and diffServRandomDropMaxThreshPkts
represent Qmax. diffServAlgDropQThreshold represents Qclip.
diffServRandomDropInvProbMax represents Pmax (inverse). This MIB
does not represent Pmin (assumed to be zero unless otherwise
represented). In addition, since message memory is finite, queues
generally have some upper bound above which they are incapable of
storing additional traffic. Normally this number is equal to Qclip,
specified by diffServAlgDropQThreshold.
Baker, et. al. Standards Track [Page 14]
RFC 3289 Differentiated Services MIB May 2002
AlgDrop Queue
+-----------------+ +-------+
--->| Next ---------+--+------------------->| Next -+--> ...
| QMeasure -------+--+ | ... |
| QThreshold | RandomDrop +-------+
| Type=randomDrop | +----------------+
| Specific -------+---->| MinThreshBytes |
+-----------------+ | MaxThreshBytes |
| ProbMax |
| Weight |
| SamplingRate |
+----------------+
Figure 1: Example Use of the RandomDropTable for Random Droppers
Each random dropper specification is associated with a queue. This
allows multiple drop processes (of same or different types) to be
associated with the same queue, as different PHB implementations may
require. This also allows for sequences of multiple droppers if
necessary.
The calculation of a smoothed queue length may also have an important
bearing on the behavior of the dropper: parameters may include the
sampling interval or rate, and the weight of each sample. The
performance may be very sensitive to the values of these parameters
and a wide range of possible values may be required due to a wide
range of link speeds. Most algorithms include a sample weight,
represented here by diffServRandomDropWeight. The availability of
diffServRandomDropSamplingRate as readable is important, the
information provided by Sampling Rate is essential to the
configuration of diffServRandomDropWeight. Having Sampling Rate be
configurable is also helpful, as line speed increases, the ability to
have queue sampling be less frequent than packet arrival is needed.
Note, however, that there is ongoing research on this topic, see e.g.
[ACTQMGMT] and [AQMROUTER].
Additional parameters may be added in an enterprise MIB module, e.g.
by using AUGMENTS on this table, to handle aspects of random drop
algorithms that are not standardized here.
When the MIB is used for configuration, diffServRandomDropNextFree
always contains a legal value for diffServRandomDropId that is not
currently used in the system's configuration.
Baker, et. al. Standards Track [Page 15]
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3.5. Queuing and Scheduling of Packets
These include Queues and Schedulers, which are inter-related in their
use of queuing techniques. By doing so, it is possible to build
multi-level schedulers, such as those which treat a set of queues as
having priority among them, and at a specific priority find a
secondary WFQ scheduler with some number of queues.
3.5.1. diffServQTable - The Class or Queue Table
The Queue Table models simple FIFO queues. The Scheduler Table
allows flexibility in constructing both simple and somewhat more
complex queuing hierarchies from those queues.
Queue Table entries are pointed at by the "next" attributes of the
upstream elements, such as diffServMeterSucceedNext or
diffServActionNext. Note that multiple upstream elements may direct
their traffic to the same Queue Table entry. For example, the
Assured Forwarding PHB suggests that all traffic marked AF11, AF12 or
AF13 be placed in the same queue, after metering, without reordering.
To accomplish that, the upstream diffServAlgDropNext pointers each
point to the same diffServQEntry.
A common requirement of a queue is that its traffic enjoy a certain
minimum or maximum rate, or that it be given a certain priority.
Functionally, the selection of such is a function of a scheduler.
The parameter is associated with the queue, however, using the
Minimum or Maximum Rate Parameters Table.
When the MIB is used for configuration, diffServQNextFree always
contains a legal value for diffServQId that is not currently used in
the system's configuration.
3.5.2. diffServSchedulerTable - The Scheduler Table
The scheduler, and therefore the Scheduler Table, accepts inputs from
either queues or a preceding scheduler. The Scheduler Table allows
flexibility in constructing both simple and somewhat more complex
queuing hierarchies from those queues.
When the MIB is used for configuration, diffServSchedulerNextFree
always contains a legal value for diffServSchedulerId that is not
currently used in the system's configuration.
3.5.3. diffServMinRateTable - The Minimum Rate Table
When the output rate of a queue or scheduler must be given a minimum
rate or a priority, this is done using the diffServMinRateTable.
Baker, et. al. Standards Track [Page 16]
RFC 3289 Differentiated Services MIB May 2002
Rates may be expressed as absolute rates, or as a fraction of
ifSpeed, and imply the use of a rate-based scheduler such as WFQ or
WRR. The use of a priority implies the use of a Priority Scheduler.
Only one of the Absolute or Relative rates needs to be set; the other
takes the relevant value as a result. Excess capacity is distributed
proportionally among the inputs to a scheduler using the assured
rate. More complex functionality may be described by augmenting this
MIB.
When a priority scheduler is used, its effect is to give the queue
the entire capacity of the subject interface less the capacity used
by higher priorities, if there is traffic present to use it. This is
true regardless of the rate specifications applied to that queue or
other queues on the interface. Policing excess traffic will mitigate
this behavior.
When the MIB is used for configuration, diffServMinRateNextFree
always contains a legal value for diffServMinRateId that is not
currently used in the system's configuration.
3.5.4. diffServMaxRateTable - The Maximum Rate Table
When the output rate of a queue or scheduler must be limited to at
most a specified maximum rate, this is done using the
diffServMaxRateTable. Rates may be expressed as absolute rates, or
as a fraction of ifSpeed. Only one of the Absolute or Relative rate
needs to be set; the other takes the relevant value as a result.
The definition of a multirate shaper requires multiple
diffServMaxRateEntries. In this case, an algorithm such as [SHAPER]
is used. In that algorithm, more than one rate is specified, and at
any given time traffic is shaped to the lowest specified rate which
exceeds the arrival rate of traffic.
When the MIB is used for configuration, diffServMaxRateNextFree
always contains a legal value for diffServMaxRateId that is not
currently used in the system's configuration.
3.5.5. Using queues and schedulers together
For representing a Strict Priority scheduler, each scheduler input is
assigned a priority with respect to all the other inputs feeding the
same scheduler, with default values for the other parameters.
Higher-priority traffic that is not being delayed for shaping will be
serviced before a lower-priority input. An example is found in
Figure 2.
Baker, et. al. Standards Track [Page 17]
RFC 3289 Differentiated Services MIB May 2002
For weighted scheduling methods, such as WFQ or WRR, the "weight" of
a given scheduler input is represented with a Minimum Service Rate
leaky-bucket profile which provides a guaranteed minimum bandwidth to
that input, if required. This is represented by a rate
diffServMinRateAbsolute; the classical weight is the ratio between
that rate and the interface speed, or perhaps the ratio between that
rate and the sum of the configured rates for classes. The rate may
be represented by a relative value, as a fraction of the interface's
current line rate, diffServMinRateRelative, to assist in cases where
line rates are variable or where a higher-level policy might be
expressed in terms of fractions of network resources. The two rate
parameters are inter-related and changes in one may be reflected in
the other. An example is found in figure 3.
+-----+
+-------+ | P S |
| Queue +------------>+ r c |
+-------+-+--------+ | i h |
|Priority| | o e |
+--------+ | r d +----------->
+-------+ | i u |
| Queue +------------>+ t l |
+-------+-+--------+ | y e |
|Priority| | r |
+--------+ +-----+
Figure 2: Priority Scheduler with two queues
For weighted scheduling methods, one can say loosely, that WRR
focuses on meeting bandwidth sharing, without concern for relative
delay amongst the queues; where WFQ controls both queue the service
order and the amount of traffic serviced, providing bandwidth sharing
and relative delay ordering amongst the queues.
A queue or scheduled set of queues (which is an input to a scheduler)
may also be capable of acting as a non-work-conserving [MODEL]
traffic shaper: this is done by defining a Maximum Service Rate
leaky-bucket profile in order to limit the scheduler bandwidth
available to that input. This is represented by a rate, in
diffServMaxRateAbsolute; the classical weight is the ratio between
that rate and the interface speed, or perhaps the ratio between that
rate and the sum of the configured rates for classes. The rate may
be represented by a relative value, as a fraction of the interface's
current line rate, diffServMaxRateRelative. This MIB presumes that
shaping is something a scheduler does to its inputs, which it models
as a queue with a maximum rate or a scheduler whose output has a
maximum rate.
Baker, et. al. Standards Track [Page 18]
RFC 3289 Differentiated Services MIB May 2002
+-----+
+-------+ | W S |
| Queue +------------>+ R c |
+-------+-+--------+ | R h |
| Rate | | e |
+--------+ | o d +----------->
+-------+ | r u |
| Queue +------------>+ l |
+-------+-+--------+ | W e |
| Rate | | F r |
+--------+ | Q |
+-----+
Figure 3: WRR or WFQ rate-based scheduler with two inputs
The same may be done on a queue, if a given class is to be shaped to
a maximum rate without shaping other classes, as in Figure 5.
Other types of priority and weighted scheduling methods can be
defined using existing parameters in diffServMinRateEntry. NOTE:
diffServSchedulerMethod uses OBJECT IDENTIFIER syntax, with the
different types of scheduling methods defined as OBJECT-IDENTITY.
+---+
+-------+ | S |
| Queue +------------>+ c |
+-------+-+--------+ | h |
| | | e +----------->
+--------+ | d +-+-------+
| u | |Shaping|
+-------+ | l | | Rate |
| Queue +------------>+ e | +-------+
+-------+-+--------+ | r |
| | +---+
+--------+
Figure 4: Shaping scheduled traffic to a known rate
Baker, et. al. Standards Track [Page 19]
RFC 3289 Differentiated Services MIB May 2002
+---+
+-------+ | S |
| Queue +------------>+ c |
+-------+-+--------+ | h |
|Min Rate| | e +----------->
+--------+ | d |
| u |
+-------+ | l |
| Queue +------------>+ e |
+-------+-+--------+ | r |
|Min Rate| | |
+--------+ | |
|Max Rate| | |
+--------+ +---+
Figure 5: Shaping one input to a work-conserving scheduler
Future scheduling methods may be defined in other MIBs. This
requires an OBJECT-IDENTITY definition, a description of how the
existing objects are reused, if they are, and any new objects they
require.
To implement an EF and two AF classes, one must use a combination of
priority and WRR/WFQ scheduling. This requires us to cascade two
schedulers. If one were to additionally shape the output of the
system to a rate lower than the interface rate, one must place an
upper bound rate on the output of the priority scheduler. See figure
6.
3.6. Example configuration for AF and EF
For the sake of argument, let us build an example with one EF class
and four AF classes using the constructs in this MIB.
3.6.1. AF and EF Ingress Interface Configuration
The ingress edge interface identifies traffic into classes, meters
it, and ensures that any excess is appropriately dealt with according
to the PHB. For AF, this means marking excess; for EF, it means
dropping excess or shaping it to a maximum rate.
Baker, et. al. Standards Track [Page 20]
RFC 3289 Differentiated Services MIB May 2002
+-----+
+-------+ | P S |
| Queue +---------------------------------->+ r c |
+-------+----------------------+--------+ | i h |
|Priority| | o e +----------->
+--------+ | r d +-+-------+
+------+ | i u | |Shaping|
+-------+ | W S +------------->+ t l | | Rate |
| Queue +------------>+ R c +-+--------+ | y e | +-------+
+-------+-+--------+ | R h | |Priority| | r |
|Min Rate| | e | +--------+ +-----+
+--------+ | o d |
+-------+ | r u |
| Queue +------------>+ l |
+-------+-+--------+ | W e |
|Min Rate| | F r |
+--------+ | Q |
+------+
Figure 6: Combined EF and AF services using cascaded schedulers.
+-----------------------+
| diffServDataPathStart |
+-----------+-----------+
|
+----------+
|
+--+--+ +-----+ +-----+ +-----+ +-----+
| AF1 +-----+ AF2 +-----+ AF3 +-----+ AF4 +-----+ EF |
+--+--+ +--+--+ +--+--+ +--+--+ +--+--+
| | | | |
+--+--+ +--+--+ +--+--+ +--+--+ +--+--+
|trTCM| |trTCM| |trTCM| |trTCM| |srTCM|
|Meter| |Meter| |Meter| |Meter| |Meter|
+-+++-+ +-+++-+ +-+++-+ +-+++-+ +-+-+-+
||| ||| ||| ||| | |
+-+||---+ +-+||---+ +-+||---+ +-+||---+ +-+-|---+
|+-+|----+ |+-+|----+ |+-+|----+ |+-+|----+ |+--+----+
||+-+-----+ ||+-+-----+ ||+-+-----+ ||+-+-----+ ||Actions|
+||Actions| +||Actions| +||Actions| +||Actions| +| |
+| | +| | +| | +| | +-+-----+
+-+-----+ +-+-----+ +-+-----+ +-+-----+ |
||| ||| ||| ||| |
VVV VVV VVV VVV V
Accepted traffic is sent to IP forwarding
Figure 7: combined EF and AF implementation, ingress side
Baker, et. al. Standards Track [Page 21]
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3.6.1.1. Classification In The Example
A packet arriving at an ingress interface picks up its policy from
the diffServDataPathTable. This points to a classifier, which will
select traffic according to some specification for each traffic
class.
An example of a classifier for an AFm class would be a set of three
classifier elements, each pointing to a Multi-field classification
parameter block identifying one of the AFmn DSCPs. Alternatively,
the filters might contain selectors for HTTP traffic or some other
application.
An example of a classifier for EF traffic might be a classifier
element pointing to a filter specifying the EF code point, a
collection of classifiers with parameter blocks specifying individual
telephone calls, or a variety of other approaches.
Typically, of course, a classifier identifies a variety of traffic
and breaks it up into separate classes. It might very well contain
fourteen classifier elements indicating the twelve AFmn DSCP values,
EF, and "everything else". These would presumably direct traffic
down six functional data paths: one for each AF or EF class, and one
for all other traffic.
3.6.1.2. AF Implementation On an Ingress Edge Interface
Each AFm class applies a Two Rate Three Color Meter, dividing traffic
into three groups. These groups of traffic conform to both specified
rates, only the higher one, or none. The intent, on the ingress
interface at the edge of the network, is to measure and appropriately
mark traffic.
3.6.1.2.1. AF Metering On an Ingress Edge Interface
Each AFm class applies a Two Rate Three Color Meter, dividing traffic
into three groups. If two rates R and S, where R < S, are specified
and traffic arrives at rate T, traffic comprising up to R bits per
second is considered to conform to the "confirmed" rate, R. If
R < T, traffic comprising up to S-R bits per second is considered to
conform to the "excess" rate, S. Any further excess is non-
conformant.
Two meter entries are used to configure this, one for the conforming
rate and one for the excess rate. The rate parameters are stored in
associated Token Bucket Parameter Entries. The "FailNext" pointer of
the lower rate Meter Entry points to the other Meter Entry; both
"SucceedNext" pointers and the "FailNext" pointer of the higher Meter
Baker, et. al. Standards Track [Page 22]
RFC 3289 Differentiated Services MIB May 2002
Entry point to lists of actions. In the color-blind mode, all three
classifier "next" entries point to the lower rate meter entry. In
the color-aware mode, the AFm1 classifier points to the lower rate
entry, the AFm2 classifier points to the higher rate entry (as it is
only compared against that rate), and the AFm3 classifier points
directly to the actions taken when both rates fail.
3.6.1.2.2. AF Actions On an Ingress Edge Interface
For network planning and perhaps for billing purposes, arriving
traffic is normally counted. Therefore, a "count" action, consisting
of an action table entry pointing to a count table entry, is
configured.
Also, traffic is marked with the appropriate DSCP. The first R bits
per second are marked AFm1, the next S-R bits per second are marked
AFm2, and the rest is marked AFm3. It may be that traffic is
arriving marked with the same DSCP, but in general, the additional
complexity of deciding that it is being remarked to the same value is
not useful. Therefore, a "mark" action, consisting of an action
table entry pointing to a mark table entry, is configured.
At this point, the usual case is that traffic is now forwarded in the
usual manner. To indicate this, the "SucceedNext" pointer of the
Mark Action is set to zeroDotZero.
3.6.1.3. EF Implementation On an Ingress Edge Interface
The EF class applies a Single Rate Two Color Meter, dividing traffic
into "conforming" and "excess" groups. The intent, on the ingress
interface at the edge of the network, is to measure and appropriately
mark conforming traffic and drop the excess.
3.6.1.3.1. EF Metering On an Ingress Edge Interface
A single rate two color (srTCM) meter requires one token bucket. It
is therefore configured using a single meter entry with a
corresponding Token Bucket Parameter Entry. Arriving traffic either
"succeeds" or "fails".
3.6.1.3.2. EF Actions On an Ingress Edge Interface
For network planning and perhaps for billing purposes, arriving
traffic that conforms to the meter is normally counted. Therefore, a
"count" action, consisting of an action table entry pointing to a
count table entry, is configured.
Baker, et. al. Standards Track [Page 23]
RFC 3289 Differentiated Services MIB May 2002
Also, traffic is (re)marked with the EF DSCP. Therefore, a "mark"
action, consisting of an action table entry pointing to a mark table
entry, is configured.
At this point, the successful traffic is now forwarded in the usual
manner. To indicate this, the "SucceedNext" pointer of the Mark
Action is set to zeroDotZero.
Traffic that exceeded the arrival policy, however, is to be dropped.
One can use a count action on this traffic if the several counters
are interesting. However, since the drop counter in the Algorithmic
Drop Entry will count packets dropped, this is not clearly necessary.
An Algorithmic Drop Entry of the type "alwaysDrop" with no successor
is sufficient.
3.7. AF and EF Egress Edge Interface Configuration
3.7.1. Classification On an Egress Edge Interface
A packet arriving at an egress interface may have been classified on
an ingress interface, and the egress interface may have access to
that information. If it is relevant, there is no reason not to use
that information. If it is not available, however, there may be a
need to (re)classify on the egress interface. In any event, it picks
up its "program" from the diffServDataPathTable. This points to a
classifier, which will select traffic according to some specification
for each traffic class.
Baker, et. al. Standards Track [Page 24]
RFC 3289 Differentiated Services MIB May 2002
+-----------------------+
| diffServDataPathStart |
+-----------+-----------+
|
+----------+
|
+--+--+ +-----+ +-----+ +-----+ +-----+
| AF1 +-----+ AF2 +-----+ AF3 +-----+ AF4 +-----+ EF |
+-+++-+ +-+++-+ +-+++-+ +-+++-+ +-+-+-+
||| ||| ||| ||| | |
+-+++-+ +-+++-+ +-+++-+ +-+++-+ +-+-+-+
|trTCM| |trTCM| |trTCM| |trTCM| |srTCM|
|Meter| |Meter| |Meter| |Meter| |Meter|
+-+++-+ +-+++-+ +-+++-+ +-+++-+ +-+-+-+
||| ||| ||| ||| | |
+-+||---+ +-+||---+ +-+||---+ +-+||---+ +-+-|---+
|+-+|----+ |+-+|----+ |+-+|----+ |+-+|----+ |+--+----+
||+-+-----+ ||+-+-----+ ||+-+-----+ ||+-+-----+ ||Actions|
+||Actions| +||Actions| +||Actions| +||Actions| +| |
+| | +| | +| | +| | +-+-----+
+-+-----+ +-+-----+ +-+-----+ +-+-----+ |
||| ||| ||| ||| |
+-+++--+ +-+++--+ +-+++--+ +-+++--+ +--+---+
| Queue| | Queue| | Queue| | Queue| | Queue|
+--+---+ +--+---+ +--+---+ +--+---+ +--+---+
| | | | |
+--+-----------+-----------+-----------+---+ |
| WFQ/WRR Scheduler | |
+--------------------------------------+---+ |
| |
+-----+-----------+----+
| Priority Scheduler |
+----------+-----------+
|
V
Figure 8: combined EF and AF implementation
An example of a classifier for an AFm class would be a succession of
three classifier elements, each pointing to a Multi-field
classification parameter block identifying one of the AFmn DSCPs.
Alternatively, the filter might contain selectors for HTTP traffic or
some other application.
Baker, et. al. Standards Track [Page 25]
RFC 3289 Differentiated Services MIB May 2002
An example of a classifier for EF traffic might be either a
classifier element pointing to a Multi-field parameter specifying the
EF code point, or a collection of classifiers with parameter blocks
specifying individual telephone calls, or a variety of other
approaches.
Each classifier delivers traffic to appropriate functional data path
elements.
3.7.2. AF Implementation On an Egress Edge Interface
Each AFm class applies a Two Rate Three Color Meter, dividing traffic
into three groups. These groups of traffic conform to both specified
rates, only the higher one, or none. The intent, on the ingress
interface at the edge of the network, is to measure and appropriately
mark traffic.
3.7.2.1. AF Metering On an Egress Edge Interface
Each AFm class applies a Two Rate Three Color Meter, dividing traffic
into three groups. If two rates R and S, where R < S, are specified
and traffic arrives at rate T, traffic comprising up to R bits per
second is considered to conform to the "confirmed" rate, R. If
R < T, traffic comprising up to S-R bits per second is considered to
conform to the "excess" rate, S. Any further excess is non-
conformant.
Two meter entries are used to configure this, one for the conforming
rate and one for the excess rate. The rate parameters are stored in
associated Token Bucket Parameter Entries. The "FailNext" pointer of
the lower rate Meter Entry points to the other Meter Entry; both
"SucceedNext" pointers and the "FailNext" pointer of the higher Meter
Entry point to lists of actions. In the color-blind mode, all three
classifier "next" entries point to the lower rate meter entry. In
the color-aware mode, the AFm1 classifier points to the lower rate
entry, the AFm2 classifier points to the higher rate entry (as it is
only compared against that rate), and the AFm3 classifier points
directly to the actions taken when both rates fail.
Baker, et. al. Standards Track [Page 26]
RFC 3289 Differentiated Services MIB May 2002
+-----------------------------------------------------+
| Classifier |
+--------+--------------------------------------------+
|Green| Yellow| Red
| | |
+--+-----+-------+--+ Fail +--------------------+
| Meter +------+ Meter |
+--+----------------+ +---+-------+--------+
| Succeed (Green) | |Fail (Red)
| +---------+ |
| | Succeed (Yellow)|
+----+----+ +----+----+ +----+----+
| Count | | Count | | Count |
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+----+----+ +----+----+ +----+----+
|Mark AFx1| |Mark AFx2| |Mark AFx3|
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+----+----+ +----+----+ +----+----+
| Random | | Random | | Random |
| Drop | | Drop | | Drop |
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+--------+-----------------+-----------------+--------+
| Queue |
+--------------------------+--------------------------+
|
+----+----+
| Rate |
|Scheduler|
+----+----+
|
Figure 9a: Typical AF Edge egress interface configuration,
using color-blind meters
Baker, et. al. Standards Track [Page 27]
RFC 3289 Differentiated Services MIB May 2002
+-----------------------------------------------------+
| Classifier |
+--------+--------------------------------------------+
|Green | Yellow | Red
| | |
+----+----+ +----+----+ |
| Count | | Count | |
| Action +-------+ Action +------------+
+----+----+ Fail +----+----+ Fail |
|Succeed |Succeed |
+----+----+ +----+----+ +----+----+
| Count | | Count | | Count |
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+----+----+ +----+----+ +----+----+
|Mark AFx1| |Mark AFx2| |Mark AFx3|
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+----+----+ +----+----+ +----+----+
| Random | | Random | | Random |
| Drop | | Drop | | Drop |
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+--------+-----------------+-----------------+--------+
| Queue |
+--------------------------+--------------------------+
|
+----+----+
| Rate |
|Scheduler|
+----+----+
|
Figure 9b: Typical AF Edge egress interface configuration,
using color-aware meters
Baker, et. al. Standards Track [Page 28]
RFC 3289 Differentiated Services MIB May 2002
+-----------------------------------------------------+
| Classifier |
+--------+-----------------+-----------------+--------+
| Green | Yellow | Red
| | |
+----+----+ +----+----+ +----+----+
| Count | | Count | | Count |
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+----+----+ +----+----+ +----+----+
| Random | | Random | | Random |
| Drop | | Drop | | Drop |
| Action | | Action | | Action |
+----+----+ +----+----+ +----+----+
| | |
+--------+-----------------+-----------------+--------+
| Queue |
+--------------------------+--------------------------+
|
+----+----+
| Rate |
|Scheduler|
+----+----+
|
Figure 10: Typical AF Edge core interface configuration
3.7.2.2. AF Actions On an Egress Edge Interface
For network planning and perhaps for billing purposes, departing
traffic is normally counted. Therefore, a "count" action, consisting
of an action table entry pointing to a count table entry, is
configured.
Also, traffic may be marked with an appropriate DSCP. The first R
bits per second are marked AFm1, the next S-R bits per second are
marked AFm2, and the rest is marked AFm3. It may be that traffic is
arriving marked with the same DSCP, but in general, the additional
complexity of deciding that it is being remarked to the same value is
not useful. Therefore, a "mark" action, consisting of an action
table entry pointing to a mark table entry, is configured.
At this point, the usual case is that traffic is now queued for
transmission. The queue uses Active Queue Management, using an
algorithm such as RED. Therefore, an Algorithmic Dropper is
Baker, et. al. Standards Track [Page 29]
RFC 3289 Differentiated Services MIB May 2002
configured for each AFmn traffic stream, with a slightly lower min-
threshold (and possibly lower max-threshold) for the excess traffic
than for the committed traffic.
3.7.2.3. AF Rate-based Queuing On an Egress Edge Interface
The queue expected by AF is normally a work-conserving queue. It
usually has a specified minimum rate, and may have a maximum rate
below the bandwidth of the interface. In concept, it will use as
much bandwidth as is available to it, but assure the lower bound.
Common ways to implement this include various forms of Weighted Fair
Queuing (WFQ) or Weighted Round Robin (WRR). Integrated over a
longer interval, these give each class a predictable throughput rate.
They differ in that over short intervals they will order traffic
differently. In general, traffic classes that keep traffic in queue
will tend to absorb latency from queues with lower mean occupancy, in
exchange for which they make use of any available capacity.
3.7.3. EF Implementation On an Egress Edge Interface
The EF class applies a Single Rate Two Color Meter, dividing traffic
into "conforming" and "excess" groups. The intent, on the egress
interface at the edge of the network, is to measure and appropriately
mark conforming traffic and drop the excess.
3.7.3.1. EF Metering On an Egress Edge Interface
A single rate two color (srTCM) meter requires one token bucket. It
is therefore configured using a single meter entry with a
corresponding Token Bucket Parameter Entry. Arriving traffic either
"succeeds" or "fails".
3.7.3.2. EF Actions On an Egress Edge Interface
For network planning and perhaps for billing purposes, departing
traffic that conforms to the meter is normally counted. Therefore, a
"count" action, consisting of an action table entry pointing to a
count table entry, is configured.
Also, traffic is (re)marked with the EF DSCP. Therefore, a "mark"
action, consisting of an action table entry pointing to a mark table
entry, is configured.
Baker, et. al. Standards Track [Page 30]
RFC 3289 Differentiated Services MIB May 2002
+-----------------------------------------------------+
| Classifier |
+-------------------------+---------------------------+
| Voice
|
+-------------+----------+
| Meter |
+----+-------------+-----+
| Succeed | Fail
| |
+----+----+ +----+----+
| Count | | Always |
| Action | | Drop |
+----+----+ | Action |
| +---------+
+----+---------+
| Algorithmic |
| Drop Action |
+----+---------+
|
+----------------+---------------+
| Queue |
+----------------+---------------+
|
+-----+-----+
| Priority |
| Scheduler |
+-----+-----+
Figure 11: Typical EF Edge (Policing) Configuration
Baker, et. al. Standards Track [Page 31]
RFC 3289 Differentiated Services MIB May 2002
+--------------------------------+
| Classifier |
+----------------+---------------+
| Voice
|
+----+----+
| Count |
| Action |
+----+----+
|
+------+-------+
| Algorithmic |
| Drop Action |
+------+-------+
|
+----------------+---------------+
| Queue |
+----------------+---------------+
|
+-----+-----+
| Priority |
| Scheduler |
+-----+-----+
Figure 12: Typical EF Core interface Configuration
At this point, the successful traffic is now queued for transmission,
using a priority queue or perhaps a rate-based queue with significant
over-provision. Since the amount of traffic present is known, one
might not drop from this queue at all.
Traffic that exceeded the policy, however, is dropped. A count
action can be used on this traffic if the several counters are
interesting. However, since the drop counter in the Algorithmic Drop
Entry will count packets dropped, this is not clearly necessary. An
Algorithmic Drop Entry of the type "alwaysDrop" with no successor is
sufficient.
3.7.3.3. EF Priority Queuing On an Egress Edge Interface
The normal implementation is a priority queue, to minimize induced
jitter. A separate queue is used for each EF class, with a strict
ordering.
Baker, et. al. Standards Track [Page 32]
RFC 3289 Differentiated Services MIB May 2002
4. Conventions used in this MIB
4.1. The use of RowPointer to indicate data path linkage
RowPointer is a textual convention used to identify a conceptual row
in a MIB Table by pointing to one of its objects. One of the ways
this MIB uses it is to indicate succession, pointing to data path
linkage table entries.
For succession, it answers the question "what happens next?". Rather
than presume that the next table must be as specified in the
conceptual model [MODEL] and providing its index, the RowPointer
takes you to the MIB row representing that thing. In the
diffServMeterTable, for example, the diffServMeterFailNext RowPointer
might take you to another meter, while the diffServMeterSucceedNext
RowPointer would take you to an action.
Since a RowPointer is not tied to any specific object except by the
value it contains, it is possible and acceptable to use RowPointers
to merge data paths. An obvious example of such a use is in the
classifier: traffic matching the DSCPs AF11, AF12, and AF13 might be
presented to the same meter in order to perform the processing
described in the Assured Forwarding PHB. Another use would be to
merge data paths from several interfaces; if they represent a single
service contract, having them share a common set of counters and
common policy may be a desirable configuration. Note well, however,
that such configurations may have related implementation issues - if
Differentiated Services processing for the interfaces is implemented
in multiple forwarding engines, the engines will need to communicate
if they are to implement such a feature. An implementation that
fails to provide this capability is not considered to have failed the
intention of this MIB or of the [MODEL]; an implementation that does
provide it is not considered superior from a standards perspective.
NOTE -- the RowPointer construct is used to connect the functional
data paths. The [MODEL] describes these as TCBs, as an aid to
understanding. This MIB, however, does not model TCBs directly.
It operates at a lower level of abstraction using only individual
elements, connected in succession by RowPointers. Therefore, the
concept of TCBs enclosing individual Functional Data Path elements
is not directly applicable to this MIB, although management tools
that use this MIB may employ such a concept.
It is possible that a path through a device following a set of
RowPointers is indeterminate i.e. it ends in a dangling RowPointer.
Guidance is provided in the MIB module's DESCRIPTION-clause for each
of the linkage attribute. In general, for both zeroDotZero and
dangling RowPointer, it is assumed the data path ends and the traffic
Baker, et. al. Standards Track [Page 33]
RFC 3289 Differentiated Services MIB May 2002
should be given to the next logical part of the device, usually a
forwarding process or a transmission engine, or the proverbial bit-
bucket. Any variation from this usage is indicated by the attribute
affected.
4.2. The use of RowPointer to indicate parameters
RowPointer is also used in this MIB to indicate parameterization, for
pointing to parameterization table entries.
For indirection (as in the diffServClfrElementTable), the idea is to
allow other MIBs, including proprietary ones, to define new and
arcane filters - MAC headers, IPv4 and IPv6 headers, BGP Communities
and all sorts of other things - while still utilizing the structures
of this MIB. This is a form of class inheritance (in "object
oriented" language): it allows base object definitions ("classes") to
be extended in proprietary or standard ways, in the future, by other
documents.
RowPointer also clearly indicates the identified conceptual row's
content does not change, hence they can be simultaneously used and
pointed to, by more than one data path linkage table entries. The
identification of RowPointer allows higher level policy mechanisms to
take advantage of this characteristic.
4.3. Conceptual row creation and deletion
A number of conceptual tables defined in this MIB use as an index an
arbitrary integer value, unique across the scope of the agent. In
order to help with multi-manager row-creation problems, a mechanism
must be provided to allow a manager to obtain unique values for such
an index and to ensure that, when used, the manager knows whether it
got what it wanted or not.
Typically, such a table has an associated NextFree variable e.g.
diffServClfrNextFree which provides a suitable value for the index of
the next row to be created e.g. diffServClfrId. The value zero is
used to indicate that the agent can configure no more entries. The
table also has a columnar Status attribute with RowStatus syntax [RFC
2579].
Generally, if a manager attempts to create a row, the agent will
create the row and return success. If the agent has insufficient
resources or such a row already exists, then it returns an error. A
manager must be prepared to try again in such circumstances, probably
by re-reading the NextFree to obtain a new index value in case a
second manager had got in between the first manager's read of the
NextFree value and the first manager's row-creation attempt.
Baker, et. al. Standards Track [Page 34]
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To simplify management creation and deletion of rows in this MIB, the
agent is expected to assist in maintaining its consistency. It may
accomplish this by maintaining internal usage counters for any row
that might be pointed to by a RowPointer, or by any equivalent means.
When a RowPointer is created or written, and the row it points to
does not exist, the SET returns an inconsistentValue error. When a
RowStatus variable is set to 'destroy' but the usage counter is non-
zero, the SET returns no error but the indicated row is left intact.
The agent should later remove the row in the event that the usage
counter becomes zero.
The use of RowStatus is covered in more detail in [RFC 2579].
5. Extending this MIB
With the structures of this MIB divided into data path linkage tables
and parameterization tables, and with the use of RowPointer, new data
path linkage and parameterization tables can be defined in other MIB
modules, and used with tables defined in this MIB. This MIB does not
limit the type of entries its RowPointer attributes can point to,
hence new functional data path elements can be defined in other MIBs
and integrated with functional data path elements of this MIB. For
example, new Action functional data path element can be defined for
Traffic Engineering and be integrated with Differentiated Services
functional data path elements, possibly used within the same data
path sharing the same classifiers and meters.
It is more likely that new parameterization tables will be created in
other MIBs as new methods or proprietary methods get deployed for
existing Differentiated Services Functional Data Path Elements. For
example, different kinds of filters can be defined by using new
filter parameterization tables. New scheduling methods can be
deployed by defining new scheduling method OIDs and new scheduling
parameter tables.
Notice both new data path linkage tables and parameterization tables
can be added without needing to change this MIB document or affect
existing tables and their usage.
6. MIB Definition
DIFFSERV-DSCP-TC DEFINITIONS ::= BEGIN
IMPORTS
Integer32, MODULE-IDENTITY, mib-2
FROM SNMPv2-SMI
TEXTUAL-CONVENTION
FROM SNMPv2-TC;
Baker, et. al. Standards Track [Page 35]
RFC 3289 Differentiated Services MIB May 2002
diffServDSCPTC MODULE-IDENTITY
LAST-UPDATED "200205090000Z"
ORGANIZATION "IETF Differentiated Services WG"
CONTACT-INFO
" Fred Baker
Cisco Systems
1121 Via Del Rey
Santa Barbara, CA 93117, USA
E-mail: fred@cisco.com
Kwok Ho Chan
Nortel Networks
600 Technology Park Drive
Billerica, MA 01821, USA
E-mail: khchan@nortelnetworks.com
Andrew Smith
Harbour Networks
Jiuling Building
21 North Xisanhuan Ave.
Beijing, 100089, PRC
E-mail: ah_smith@acm.org
Differentiated Services Working Group:
diffserv@ietf.org"
DESCRIPTION
"The Textual Conventions defined in this module should be used
whenever a Differentiated Services Code Point is used in a MIB."
REVISION "200205090000Z"
DESCRIPTION
"Initial version, published as RFC 3289."
::= { mib-2 96 }
Dscp ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"A Differentiated Services Code-Point that may be used for
marking a traffic stream."
REFERENCE
"RFC 2474, RFC 2780"
SYNTAX Integer32 (0..63)
DscpOrAny ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"The IP header Differentiated Services Code-Point that may be
Baker, et. al. Standards Track [Page 36]
RFC 3289 Differentiated Services MIB May 2002
used for discriminating among traffic streams. The value -1 is
used to indicate a wild card i.e. any value."
REFERENCE
"RFC 2474, RFC 2780"
SYNTAX Integer32 (-1 | 0..63)
END
DIFFSERV-MIB DEFINITIONS ::= BEGIN
IMPORTS
Unsigned32, Counter64, MODULE-IDENTITY, OBJECT-TYPE,
OBJECT-IDENTITY, zeroDotZero, mib-2
FROM SNMPv2-SMI
TEXTUAL-CONVENTION, RowStatus, RowPointer,
StorageType, AutonomousType
FROM SNMPv2-TC
MODULE-COMPLIANCE, OBJECT-GROUP
FROM SNMPv2-CONF
ifIndex, InterfaceIndexOrZero
FROM IF-MIB
InetAddressType, InetAddress, InetAddressPrefixLength,
InetPortNumber
FROM INET-ADDRESS-MIB
BurstSize
FROM INTEGRATED-SERVICES-MIB
Dscp, DscpOrAny
FROM DIFFSERV-DSCP-TC;
diffServMib MODULE-IDENTITY
LAST-UPDATED "200202070000Z"
ORGANIZATION "IETF Differentiated Services WG"
CONTACT-INFO
" Fred Baker
Cisco Systems
1121 Via Del Rey
Santa Barbara, CA 93117, USA
E-mail: fred@cisco.com
Kwok Ho Chan
Nortel Networks
600 Technology Park Drive
Billerica, MA 01821, USA
E-mail: khchan@nortelnetworks.com
Andrew Smith
Harbour Networks
Jiuling Building
Baker, et. al. Standards Track [Page 37]
RFC 3289 Differentiated Services MIB May 2002
21 North Xisanhuan Ave.
Beijing, 100089, PRC
E-mail: ah_smith@acm.org
Differentiated Services Working Group:
diffserv@ietf.org"
DESCRIPTION
"This MIB defines the objects necessary to manage a device that
uses the Differentiated Services Architecture described in RFC
2475. The Conceptual Model of a Differentiated Services Router
provides supporting information on how such a router is modeled."
REVISION "200202070000Z"
DESCRIPTION
"Initial version, published as RFC 3289."
::= { mib-2 97 }
diffServMIBObjects OBJECT IDENTIFIER ::= { diffServMib 1 }
diffServMIBConformance OBJECT IDENTIFIER ::= { diffServMib 2 }
diffServMIBAdmin OBJECT IDENTIFIER ::= { diffServMib 3 }
IndexInteger ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"An integer which may be used as a table index."
SYNTAX Unsigned32 (1..4294967295)
IndexIntegerNextFree ::= TEXTUAL-CONVENTION
DISPLAY-HINT "d"
STATUS current
DESCRIPTION
"An integer which may be used as a new Index in a table.
The special value of 0 indicates that no more new entries can be
created in the relevant table.
When a MIB is used for configuration, an object with this SYNTAX
always contains a legal value (if non-zero) for an index that is
not currently used in the relevant table. The Command Generator
(Network Management Application) reads this variable and uses the
(non-zero) value read when creating a new row with an SNMP SET.
When the SET is performed, the Command Responder (agent) must
determine whether the value is indeed still unused; Two Network
Management Applications may attempt to create a row
(configuration entry) simultaneously and use the same value. If
it is currently unused, the SET succeeds and the Command
Responder (agent) changes the value of this object, according to
an implementation-specific algorithm. If the value is in use,
Baker, et. al. Standards Track [Page 38]
RFC 3289 Differentiated Services MIB May 2002
however, the SET fails. The Network Management Application must
then re-read this variable to obtain a new usable value.
An OBJECT-TYPE definition using this SYNTAX MUST specify the
relevant table for which the object is providing this
functionality."
SYNTAX Unsigned32 (0..4294967295)
IfDirection ::= TEXTUAL-CONVENTION
STATUS current
DESCRIPTION
"IfDirection specifies a direction of data travel on an
interface. 'inbound' traffic is operated on during reception from
the interface, while 'outbound' traffic is operated on prior to
transmission on the interface."
SYNTAX INTEGER {
inbound(1), -- ingress interface
outbound(2) -- egress interface
}
--
-- Data Path
--
diffServDataPath OBJECT IDENTIFIER ::= { diffServMIBObjects 1 }
--
-- Data Path Table
--
-- The Data Path Table enumerates the Differentiated Services
-- Functional Data Paths within this device. Each entry in this table
-- is indexed by ifIndex and ifDirection. Each entry provides the
-- first Differentiated Services Functional Data Path Element to
-- process data flowing along specific data path. This table should
-- have at most two entries for each interface capable of
-- Differentiated Services processing on this device: ingress and
-- egress.
-- Note that Differentiated Services Functional Data Path Elements
-- linked together using their individual next pointers and anchored by
-- an entry of the diffServDataPathTable constitute a functional data
-- path.
--
diffServDataPathTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServDataPathEntry
MAX-ACCESS not-accessible
STATUS current
Baker, et. al. Standards Track [Page 39]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"The data path table contains RowPointers indicating the start of
the functional data path for each interface and traffic direction
in this device. These may merge, or be separated into parallel
data paths."
::= { diffServDataPath 1 }
diffServDataPathEntry OBJECT-TYPE
SYNTAX DiffServDataPathEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the data path table indicates the start of a single
Differentiated Services Functional Data Path in this device.
These are associated with individual interfaces, logical or
physical, and therefore are instantiated by ifIndex. Therefore,
the interface index must have been assigned, according to the
procedures applicable to that, before it can be meaningfully
used. Generally, this means that the interface must exist.
When diffServDataPathStorage is of type nonVolatile, however,
this may reflect the configuration for an interface whose ifIndex
has been assigned but for which the supporting implementation is
not currently present."
INDEX { ifIndex, diffServDataPathIfDirection }
::= { diffServDataPathTable 1 }
DiffServDataPathEntry ::= SEQUENCE {
diffServDataPathIfDirection IfDirection,
diffServDataPathStart RowPointer,
diffServDataPathStorage StorageType,
diffServDataPathStatus RowStatus
}
diffServDataPathIfDirection OBJECT-TYPE
SYNTAX IfDirection
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"IfDirection specifies whether the reception or transmission path
for this interface is in view."
::= { diffServDataPathEntry 1 }
diffServDataPathStart OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
Baker, et. al. Standards Track [Page 40]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"This selects the first Differentiated Services Functional Data
Path Element to handle traffic for this data path. This
RowPointer should point to an instance of one of:
diffServClfrEntry
diffServMeterEntry
diffServActionEntry
diffServAlgDropEntry
diffServQEntry
A value of zeroDotZero in this attribute indicates that no
Differentiated Services treatment is performed on traffic of this
data path. A pointer with the value zeroDotZero normally
terminates a functional data path.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServDataPathEntry 2 }
diffServDataPathStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServDataPathEntry 3 }
diffServDataPathStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time."
::= { diffServDataPathEntry 4 }
--
-- Classifiers
--
diffServClassifier OBJECT IDENTIFIER ::= { diffServMIBObjects 2 }
--
Baker, et. al. Standards Track [Page 41]
RFC 3289 Differentiated Services MIB May 2002
-- Classifier Table
--
-- The Classifier Table allows multiple classifier elements, of same or
-- different types, to be used together. A classifier must completely
-- classify all packets presented to it. This means that all traffic
-- presented to a classifier must match at least one classifier element
-- within the classifier, with the classifier element parameters
-- specified by a filter.
-- If there is ambiguity between classifier elements of different
-- classifier, classifier linkage order indicates their precedence; the
-- first classifier in the link is applied to the traffic first.
-- Entries in the classifier element table serves as the anchor for
-- each classification pattern, defined in filter table entries. Each
-- classifier element table entry also specifies the subsequent
-- downstream Differentiated Services Functional Data Path Element when
-- the classification pattern is satisfied. Each entry in the
-- classifier element table describes one branch of the fan-out
-- characteristic of a classifier indicated in the Informal
-- Differentiated Services Model section 4.1. A classifier is composed
-- of one or more classifier elements.
diffServClfrNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServClfrId, or a
zero to indicate that none exist."
::= { diffServClassifier 1 }
diffServClfrTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServClfrEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table enumerates all the diffserv classifier functional
data path elements of this device. The actual classification
definitions are defined in diffServClfrElementTable entries
belonging to each classifier.
An entry in this table, pointed to by a RowPointer specifying an
instance of diffServClfrStatus, is frequently used as the name
for a set of classifier elements, which all use the index
diffServClfrId. Per the semantics of the classifier element
table, these entries constitute one or more unordered sets of
tests which may be simultaneously applied to a message to
Baker, et. al. Standards Track [Page 42]
RFC 3289 Differentiated Services MIB May 2002
classify it.
The primary function of this table is to ensure that the value of
diffServClfrId is unique before attempting to use it in creating
a diffServClfrElementEntry. Therefore, the diffServClfrEntry must
be created on the same SET as the diffServClfrElementEntry, or
before the diffServClfrElementEntry is created."
::= { diffServClassifier 2 }
diffServClfrEntry OBJECT-TYPE
SYNTAX DiffServClfrEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the classifier table describes a single classifier.
All classifier elements belonging to the same classifier use the
classifier's diffServClfrId as part of their index."
INDEX { diffServClfrId }
::= { diffServClfrTable 1 }
DiffServClfrEntry ::= SEQUENCE {
diffServClfrId IndexInteger,
diffServClfrStorage StorageType,
diffServClfrStatus RowStatus
}
diffServClfrId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the classifier entries. Managers
should obtain new values for row creation in this table by
reading diffServClfrNextFree."
::= { diffServClfrEntry 1 }
diffServClfrStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServClfrEntry 2 }
diffServClfrStatus OBJECT-TYPE
Baker, et. al. Standards Track [Page 43]
RFC 3289 Differentiated Services MIB May 2002
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServClfrEntry 3 }
--
-- Classifier Element Table
--
diffServClfrElementNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServClfrElementId,
or a zero to indicate that none exist."
::= { diffServClassifier 3 }
diffServClfrElementTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServClfrElementEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The classifier element table enumerates the relationship between
classification patterns and subsequent downstream Differentiated
Services Functional Data Path elements.
diffServClfrElementSpecific points to a filter that specifies the
classification parameters. A classifier may use filter tables of
different types together.
One example of a filter table defined in this MIB is
diffServMultiFieldClfrTable, for IP Multi-Field Classifiers
(MFCs). Such an entry might identify anything from a single
micro-flow (an identifiable sub-session packet stream directed
from one sending transport to the receiving transport or
transports), or aggregates of those such as the traffic from a
host, traffic for an application, or traffic between two hosts
using an application and a given DSCP. The standard Behavior
Aggregate used in the Differentiated Services Architecture is
encoded as a degenerate case of such an aggregate - the traffic
using a particular DSCP value.
Filter tables for other filter types may be defined elsewhere."
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RFC 3289 Differentiated Services MIB May 2002
::= { diffServClassifier 4 }
diffServClfrElementEntry OBJECT-TYPE
SYNTAX DiffServClfrElementEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the classifier element table describes a single
element of the classifier."
INDEX { diffServClfrId, diffServClfrElementId }
::= { diffServClfrElementTable 1 }
DiffServClfrElementEntry ::= SEQUENCE {
diffServClfrElementId IndexInteger,
diffServClfrElementPrecedence Unsigned32,
diffServClfrElementNext RowPointer,
diffServClfrElementSpecific RowPointer,
diffServClfrElementStorage StorageType,
diffServClfrElementStatus RowStatus
}
diffServClfrElementId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Classifier Element entries.
Managers obtain new values for row creation in this table by
reading diffServClfrElementNextFree."
::= { diffServClfrElementEntry 1 }
diffServClfrElementPrecedence OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The relative order in which classifier elements are applied:
higher numbers represent classifier element with higher
precedence. Classifier elements with the same order must be
unambiguous i.e. they must define non-overlapping patterns, and
are considered to be applied simultaneously to the traffic
stream. Classifier elements with different order may overlap in
their filters: the classifier element with the highest order
that matches is taken.
On a given interface, there must be a complete classifier in
place at all times in the ingress direction. This means one or
more filters must match any possible pattern. There is no such
Baker, et. al. Standards Track [Page 45]
RFC 3289 Differentiated Services MIB May 2002
requirement in the egress direction."
::= { diffServClfrElementEntry 2 }
diffServClfrElementNext OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This attribute provides one branch of the fan-out functionality
of a classifier described in the Informal Differentiated Services
Model section 4.1.
This selects the next Differentiated Services Functional Data
Path Element to handle traffic for this data path. This
RowPointer should point to an instance of one of:
diffServClfrEntry
diffServMeterEntry
diffServActionEntry
diffServAlgDropEntry
diffServQEntry
A value of zeroDotZero in this attribute indicates no further
Differentiated Services treatment is performed on traffic of this
data path. The use of zeroDotZero is the normal usage for the
last functional data path element of the current data path.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServClfrElementEntry 3 }
diffServClfrElementSpecific OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A pointer to a valid entry in another table, filter table, that
describes the applicable classification parameters, e.g. an entry
in diffServMultiFieldClfrTable.
The value zeroDotZero is interpreted to match anything not
matched by another classifier element - only one such entry may
exist for each classifier.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
Baker, et. al. Standards Track [Page 46]
RFC 3289 Differentiated Services MIB May 2002
becomes inactive by other means, the element is ignored."
::= { diffServClfrElementEntry 4 }
diffServClfrElementStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServClfrElementEntry 5 }
diffServClfrElementStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServClfrElementEntry 6 }
--
-- IP Multi-field Classification Table
--
-- Classification based on six different fields in the IP header.
-- Functional Data Paths may share definitions by using the same entry.
--
diffServMultiFieldClfrNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for
diffServMultiFieldClfrId, or a zero to indicate that none exist."
::= { diffServClassifier 5 }
diffServMultiFieldClfrTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServMultiFieldClfrEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"A table of IP Multi-field Classifier filter entries that a
Baker, et. al. Standards Track [Page 47]
RFC 3289 Differentiated Services MIB May 2002
system may use to identify IP traffic."
::= { diffServClassifier 6 }
diffServMultiFieldClfrEntry OBJECT-TYPE
SYNTAX DiffServMultiFieldClfrEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An IP Multi-field Classifier entry describes a single filter."
INDEX { diffServMultiFieldClfrId }
::= { diffServMultiFieldClfrTable 1 }
DiffServMultiFieldClfrEntry ::= SEQUENCE {
diffServMultiFieldClfrId IndexInteger,
diffServMultiFieldClfrAddrType InetAddressType,
diffServMultiFieldClfrDstAddr InetAddress,
diffServMultiFieldClfrDstPrefixLength InetAddressPrefixLength,
diffServMultiFieldClfrSrcAddr InetAddress,
diffServMultiFieldClfrSrcPrefixLength InetAddressPrefixLength,
diffServMultiFieldClfrDscp DscpOrAny,
diffServMultiFieldClfrFlowId Unsigned32,
diffServMultiFieldClfrProtocol Unsigned32,
diffServMultiFieldClfrDstL4PortMin InetPortNumber,
diffServMultiFieldClfrDstL4PortMax InetPortNumber,
diffServMultiFieldClfrSrcL4PortMin InetPortNumber,
diffServMultiFieldClfrSrcL4PortMax InetPortNumber,
diffServMultiFieldClfrStorage StorageType,
diffServMultiFieldClfrStatus RowStatus
}
diffServMultiFieldClfrId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the MultiField Classifier filter
entries. Managers obtain new values for row creation in this
table by reading diffServMultiFieldClfrNextFree."
::= { diffServMultiFieldClfrEntry 1 }
diffServMultiFieldClfrAddrType OBJECT-TYPE
SYNTAX InetAddressType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The type of IP address used by this classifier entry. While
other types of addresses are defined in the InetAddressType
Baker, et. al. Standards Track [Page 48]
RFC 3289 Differentiated Services MIB May 2002
textual convention, and DNS names, a classifier can only look at
packets on the wire. Therefore, this object is limited to IPv4
and IPv6 addresses."
::= { diffServMultiFieldClfrEntry 2 }
diffServMultiFieldClfrDstAddr OBJECT-TYPE
SYNTAX InetAddress
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The IP address to match against the packet's destination IP
address. This may not be a DNS name, but may be an IPv4 or IPv6
prefix. diffServMultiFieldClfrDstPrefixLength indicates the
number of bits that are relevant."
::= { diffServMultiFieldClfrEntry 3 }
diffServMultiFieldClfrDstPrefixLength OBJECT-TYPE
SYNTAX InetAddressPrefixLength
UNITS "bits"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The length of the CIDR Prefix carried in
diffServMultiFieldClfrDstAddr. In IPv4 addresses, a length of 0
indicates a match of any address; a length of 32 indicates a
match of a single host address, and a length between 0 and 32
indicates the use of a CIDR Prefix. IPv6 is similar, except that
prefix lengths range from 0..128."
DEFVAL { 0 }
::= { diffServMultiFieldClfrEntry 4 }
diffServMultiFieldClfrSrcAddr OBJECT-TYPE
SYNTAX InetAddress
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The IP address to match against the packet's source IP address.
This may not be a DNS name, but may be an IPv4 or IPv6 prefix.
diffServMultiFieldClfrSrcPrefixLength indicates the number of
bits that are relevant."
::= { diffServMultiFieldClfrEntry 5 }
diffServMultiFieldClfrSrcPrefixLength OBJECT-TYPE
SYNTAX InetAddressPrefixLength
UNITS "bits"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
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RFC 3289 Differentiated Services MIB May 2002
"The length of the CIDR Prefix carried in
diffServMultiFieldClfrSrcAddr. In IPv4 addresses, a length of 0
indicates a match of any address; a length of 32 indicates a
match of a single host address, and a length between 0 and 32
indicates the use of a CIDR Prefix. IPv6 is similar, except that
prefix lengths range from 0..128."
DEFVAL { 0 }
::= { diffServMultiFieldClfrEntry 6 }
diffServMultiFieldClfrDscp OBJECT-TYPE
SYNTAX DscpOrAny
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The value that the DSCP in the packet must have to match this
entry. A value of -1 indicates that a specific DSCP value has not
been defined and thus all DSCP values are considered a match."
DEFVAL { -1 }
::= { diffServMultiFieldClfrEntry 7 }
diffServMultiFieldClfrFlowId OBJECT-TYPE
SYNTAX Unsigned32 (0..1048575)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The flow identifier in an IPv6 header."
::= { diffServMultiFieldClfrEntry 8 }
diffServMultiFieldClfrProtocol OBJECT-TYPE
SYNTAX Unsigned32 (0..255)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The IP protocol to match against the IPv4 protocol number or the
IPv6 Next- Header number in the packet. A value of 255 means
match all. Note the protocol number of 255 is reserved by IANA,
and Next-Header number of 0 is used in IPv6."
DEFVAL { 255 }
::= { diffServMultiFieldClfrEntry 9 }
diffServMultiFieldClfrDstL4PortMin OBJECT-TYPE
SYNTAX InetPortNumber
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The minimum value that the layer-4 destination port number in
the packet must have in order to match this classifier entry."
DEFVAL { 0 }
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RFC 3289 Differentiated Services MIB May 2002
::= { diffServMultiFieldClfrEntry 10 }
diffServMultiFieldClfrDstL4PortMax OBJECT-TYPE
SYNTAX InetPortNumber
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The maximum value that the layer-4 destination port number in
the packet must have in order to match this classifier entry.
This value must be equal to or greater than the value specified
for this entry in diffServMultiFieldClfrDstL4PortMin."
DEFVAL { 65535 }
::= { diffServMultiFieldClfrEntry 11 }
diffServMultiFieldClfrSrcL4PortMin OBJECT-TYPE
SYNTAX InetPortNumber
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The minimum value that the layer-4 source port number in the
packet must have in order to match this classifier entry."
DEFVAL { 0 }
::= { diffServMultiFieldClfrEntry 12 }
diffServMultiFieldClfrSrcL4PortMax OBJECT-TYPE
SYNTAX InetPortNumber
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The maximum value that the layer-4 source port number in the
packet must have in order to match this classifier entry. This
value must be equal to or greater than the value specified for
this entry in diffServMultiFieldClfrSrcL4PortMin."
DEFVAL { 65535 }
::= { diffServMultiFieldClfrEntry 13 }
diffServMultiFieldClfrStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServMultiFieldClfrEntry 14 }
diffServMultiFieldClfrStatus OBJECT-TYPE
Baker, et. al. Standards Track [Page 51]
RFC 3289 Differentiated Services MIB May 2002
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServMultiFieldClfrEntry 15 }
--
-- Meters
--
diffServMeter OBJECT IDENTIFIER ::= { diffServMIBObjects 3 }
--
-- This MIB supports a variety of Meters. It includes a specific
-- definition for Token Bucket Meter, which are but one type of
-- specification. Other metering parameter sets can be defined in other
-- MIBs.
-- Multiple meter elements may be logically cascaded using their
-- diffServMeterSucceedNext and diffServMeterFailNext pointers if
-- required. One example of this might be for an AF PHB implementation
-- that uses multiple level conformance meters.
-- Cascading of individual meter elements in the MIB is intended to be
-- functionally equivalent to multiple level conformance determination
-- of a packet. The sequential nature of the representation is merely
-- a notational convenience for this MIB.
-- srTCM meters (RFC 2697) can be specified using two sets of
-- diffServMeterEntry and diffServTBParamEntry. The first set specifies
-- the Committed Information Rate and Committed Burst Size
-- token-bucket. The second set specifies the Excess Burst Size
-- token-bucket.
-- trTCM meters (RFC 2698) can be specified using two sets of
-- diffServMeterEntry and diffServTBParamEntry. The first set specifies
-- the Committed Information Rate and Committed Burst Size
-- token-bucket. The second set specifies the Peak Information Rate
-- and Peak Burst Size token-bucket.
-- tswTCM meters (RFC 2859) can be specified using two sets of
-- diffServMeterEntry and diffServTBParamEntry. The first set specifies
-- the Committed Target Rate token-bucket. The second set specifies
Baker, et. al. Standards Track [Page 52]
RFC 3289 Differentiated Services MIB May 2002
-- the Peak Target Rate token-bucket. diffServTBParamInterval in each
-- token bucket reflects the Average Interval.
--
diffServMeterNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServMeterId, or a
zero to indicate that none exist."
::= { diffServMeter 1 }
diffServMeterTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServMeterEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table enumerates specific meters that a system may use to
police a stream of traffic. The traffic stream to be metered is
determined by the Differentiated Services Functional Data Path
Element(s) upstream of the meter i.e. by the object(s) that point
to each entry in this table. This may include all traffic on an
interface.
Specific meter details are to be found in table entry referenced
by diffServMeterSpecific."
::= { diffServMeter 2 }
diffServMeterEntry OBJECT-TYPE
SYNTAX DiffServMeterEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the meter table describes a single conformance level
of a meter."
INDEX { diffServMeterId }
::= { diffServMeterTable 1 }
DiffServMeterEntry ::= SEQUENCE {
diffServMeterId IndexInteger,
diffServMeterSucceedNext RowPointer,
diffServMeterFailNext RowPointer,
diffServMeterSpecific RowPointer,
diffServMeterStorage StorageType,
diffServMeterStatus RowStatus
}
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RFC 3289 Differentiated Services MIB May 2002
diffServMeterId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Meter entries. Managers obtain new
values for row creation in this table by reading
diffServMeterNextFree."
::= { diffServMeterEntry 1 }
diffServMeterSucceedNext OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If the traffic does conform, this selects the next
Differentiated Services Functional Data Path element to handle
traffic for this data path. This RowPointer should point to an
instance of one of:
diffServClfrEntry
diffServMeterEntry
diffServActionEntry
diffServAlgDropEntry
diffServQEntry
A value of zeroDotZero in this attribute indicates that no
further Differentiated Services treatment is performed on traffic
of this data path. The use of zeroDotZero is the normal usage for
the last functional data path element of the current data path.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
DEFVAL { zeroDotZero }
::= { diffServMeterEntry 2 }
diffServMeterFailNext OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"If the traffic does not conform, this selects the next
Differentiated Services Functional Data Path element to handle
traffic for this data path. This RowPointer should point to an
instance of one of:
diffServClfrEntry
diffServMeterEntry
Baker, et. al. Standards Track [Page 54]
RFC 3289 Differentiated Services MIB May 2002
diffServActionEntry
diffServAlgDropEntry
diffServQEntry
A value of zeroDotZero in this attribute indicates no further
Differentiated Services treatment is performed on traffic of this
data path. The use of zeroDotZero is the normal usage for the
last functional data path element of the current data path.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
DEFVAL { zeroDotZero }
::= { diffServMeterEntry 3 }
diffServMeterSpecific OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This indicates the behavior of the meter by pointing to an entry
containing detailed parameters. Note that entries in that
specific table must be managed explicitly.
For example, diffServMeterSpecific may point to an entry in
diffServTBParamTable, which contains an instance of a single set
of Token Bucket parameters.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the meter always succeeds."
::= { diffServMeterEntry 4 }
diffServMeterStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServMeterEntry 5 }
diffServMeterStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
Baker, et. al. Standards Track [Page 55]
RFC 3289 Differentiated Services MIB May 2002
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServMeterEntry 6 }
--
-- Token Bucket Parameter Table
--
diffServTBParam OBJECT IDENTIFIER ::= { diffServMIBObjects 4 }
-- Each entry in the Token Bucket Parameter Table parameterize a single
-- token bucket. Multiple token buckets can be used together to
-- parameterize multiple levels of conformance.
-- Note that an entry in the Token Bucket Parameter Table can be shared
-- by multiple diffServMeterTable entries.
--
diffServTBParamNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServTBParamId, or a
zero to indicate that none exist."
::= { diffServTBParam 1 }
diffServTBParamTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServTBParamEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table enumerates a single set of token bucket meter
parameters that a system may use to police a stream of traffic.
Such meters are modeled here as having a single rate and a single
burst size. Multiple entries are used when multiple rates/burst
sizes are needed."
::= { diffServTBParam 2 }
diffServTBParamEntry OBJECT-TYPE
SYNTAX DiffServTBParamEntry
MAX-ACCESS not-accessible
STATUS current
Baker, et. al. Standards Track [Page 56]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"An entry that describes a single set of token bucket
parameters."
INDEX { diffServTBParamId }
::= { diffServTBParamTable 1 }
DiffServTBParamEntry ::= SEQUENCE {
diffServTBParamId IndexInteger,
diffServTBParamType AutonomousType,
diffServTBParamRate Unsigned32,
diffServTBParamBurstSize BurstSize,
diffServTBParamInterval Unsigned32,
diffServTBParamStorage StorageType,
diffServTBParamStatus RowStatus
}
diffServTBParamId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Token Bucket Parameter entries.
Managers obtain new values for row creation in this table by
reading diffServTBParamNextFree."
::= { diffServTBParamEntry 1 }
diffServTBParamType OBJECT-TYPE
SYNTAX AutonomousType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The Metering algorithm associated with the Token Bucket
parameters. zeroDotZero indicates this is unknown.
Standard values for generic algorithms:
diffServTBParamSimpleTokenBucket, diffServTBParamAvgRate,
diffServTBParamSrTCMBlind, diffServTBParamSrTCMAware,
diffServTBParamTrTCMBlind, diffServTBParamTrTCMAware, and
diffServTBParamTswTCM are specified in this MIB as OBJECT-
IDENTITYs; additional values may be further specified in other
MIBs."
::= { diffServTBParamEntry 2 }
diffServTBParamRate OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "kilobits per second"
MAX-ACCESS read-create
STATUS current
Baker, et. al. Standards Track [Page 57]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"The token-bucket rate, in kilobits per second (kbps). This
attribute is used for:
1. CIR in RFC 2697 for srTCM
2. CIR and PIR in RFC 2698 for trTCM
3. CTR and PTR in RFC 2859 for TSWTCM
4. AverageRate in RFC 3290."
::= { diffServTBParamEntry 3 }
diffServTBParamBurstSize OBJECT-TYPE
SYNTAX BurstSize
UNITS "Bytes"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The maximum number of bytes in a single transmission burst. This
attribute is used for:
1. CBS and EBS in RFC 2697 for srTCM
2. CBS and PBS in RFC 2698 for trTCM
3. Burst Size in RFC 3290."
::= { diffServTBParamEntry 4 }
diffServTBParamInterval OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "microseconds"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The time interval used with the token bucket. For:
1. Average Rate Meter, the Informal Differentiated Services Model
section 5.2.1, - Delta.
2. Simple Token Bucket Meter, the Informal Differentiated
Services Model section 5.1, - time interval t.
3. RFC 2859 TSWTCM, - AVG_INTERVAL.
4. RFC 2697 srTCM, RFC 2698 trTCM, - token bucket update time
interval."
::= { diffServTBParamEntry 5 }
diffServTBParamStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServTBParamEntry 6 }
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RFC 3289 Differentiated Services MIB May 2002
diffServTBParamStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServTBParamEntry 7 }
--
-- OIDs for diffServTBParamType definitions.
--
diffServTBMeters OBJECT IDENTIFIER ::= { diffServMIBAdmin 1 }
diffServTBParamSimpleTokenBucket OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Two Parameter Token Bucket Meter as described in the Informal
Differentiated Services Model section 5.2.3."
::= { diffServTBMeters 1 }
diffServTBParamAvgRate OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Average Rate Meter as described in the Informal Differentiated
Services Model section 5.2.1."
::= { diffServTBMeters 2 }
diffServTBParamSrTCMBlind OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Single Rate Three Color Marker Metering as defined by RFC 2697,
in the `Color Blind' mode as described by the RFC."
REFERENCE
"RFC 2697"
::= { diffServTBMeters 3 }
diffServTBParamSrTCMAware OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Single Rate Three Color Marker Metering as defined by RFC 2697,
in the `Color Aware' mode as described by the RFC."
REFERENCE
"RFC 2697"
Baker, et. al. Standards Track [Page 59]
RFC 3289 Differentiated Services MIB May 2002
::= { diffServTBMeters 4 }
diffServTBParamTrTCMBlind OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Two Rate Three Color Marker Metering as defined by RFC 2698, in
the `Color Blind' mode as described by the RFC."
REFERENCE
"RFC 2698"
::= { diffServTBMeters 5 }
diffServTBParamTrTCMAware OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Two Rate Three Color Marker Metering as defined by RFC 2698, in
the `Color Aware' mode as described by the RFC."
REFERENCE
"RFC 2698"
::= { diffServTBMeters 6 }
diffServTBParamTswTCM OBJECT-IDENTITY
STATUS current
DESCRIPTION
"Time Sliding Window Three Color Marker Metering as defined by
RFC 2859."
REFERENCE
"RFC 2859"
::= { diffServTBMeters 7 }
--
-- Actions
--
diffServAction OBJECT IDENTIFIER ::= { diffServMIBObjects 5 }
--
-- The Action Table allows enumeration of the different types of
-- actions to be applied to a traffic flow.
--
diffServActionNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServActionId, or a
zero to indicate that none exist."
::= { diffServAction 1 }
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RFC 3289 Differentiated Services MIB May 2002
diffServActionTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServActionEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The Action Table enumerates actions that can be performed to a
stream of traffic. Multiple actions can be concatenated. For
example, traffic exiting from a meter may be counted, marked, and
potentially dropped before entering a queue.
Specific actions are indicated by diffServActionSpecific which
points to an entry of a specific action type parameterizing the
action in detail."
::= { diffServAction 2 }
diffServActionEntry OBJECT-TYPE
SYNTAX DiffServActionEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in the action table allows description of one
specific action to be applied to traffic."
INDEX { diffServActionId }
::= { diffServActionTable 1 }
DiffServActionEntry ::= SEQUENCE {
diffServActionId IndexInteger,
diffServActionInterface InterfaceIndexOrZero,
diffServActionNext RowPointer,
diffServActionSpecific RowPointer,
diffServActionStorage StorageType,
diffServActionStatus RowStatus
}
diffServActionId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Action entries. Managers obtain
new values for row creation in this table by reading
diffServActionNextFree."
::= { diffServActionEntry 1 }
diffServActionInterface OBJECT-TYPE
SYNTAX InterfaceIndexOrZero
MAX-ACCESS read-create
STATUS current
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RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"The interface index (value of ifIndex) that this action occurs
on. This may be derived from the diffServDataPathStartEntry's
index by extension through the various RowPointers. However, as
this may be difficult for a network management station, it is
placed here as well. If this is indeterminate, the value is
zero.
This is of especial relevance when reporting the counters which
may apply to traffic crossing an interface:
diffServCountActOctets,
diffServCountActPkts,
diffServAlgDropOctets,
diffServAlgDropPkts,
diffServAlgRandomDropOctets, and
diffServAlgRandomDropPkts.
It is also especially relevant to the queue and scheduler which
may be subsequently applied."
::= { diffServActionEntry 2 }
diffServActionNext OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This selects the next Differentiated Services Functional Data
Path Element to handle traffic for this data path. This
RowPointer should point to an instance of one of:
diffServClfrEntry
diffServMeterEntry
diffServActionEntry
diffServAlgDropEntry
diffServQEntry
A value of zeroDotZero in this attribute indicates no further
Differentiated Services treatment is performed on traffic of this
data path. The use of zeroDotZero is the normal usage for the
last functional data path element of the current data path.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
DEFVAL { zeroDotZero }
::= { diffServActionEntry 3 }
diffServActionSpecific OBJECT-TYPE
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RFC 3289 Differentiated Services MIB May 2002
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A pointer to an object instance providing additional information
for the type of action indicated by this action table entry.
For the standard actions defined by this MIB module, this should
point to either a diffServDscpMarkActEntry or a
diffServCountActEntry. For other actions, it may point to an
object instance defined in some other MIB.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the Meter should be treated as
if it were not present. This may lead to incorrect policy
behavior."
::= { diffServActionEntry 4 }
diffServActionStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServActionEntry 5 }
diffServActionStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServActionEntry 6 }
-- DSCP Mark Action Table
--
-- Rows of this table are pointed to by diffServActionSpecific to
-- provide detailed parameters specific to the DSCP Mark action.
--
-- A single entry in this table can be shared by multiple
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RFC 3289 Differentiated Services MIB May 2002
-- diffServActionTable entries.
--
diffServDscpMarkActTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServDscpMarkActEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table enumerates specific DSCPs used for marking or
remarking the DSCP field of IP packets. The entries of this table
may be referenced by a diffServActionSpecific attribute."
::= { diffServAction 3 }
diffServDscpMarkActEntry OBJECT-TYPE
SYNTAX DiffServDscpMarkActEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the DSCP mark action table that describes a single
DSCP used for marking."
INDEX { diffServDscpMarkActDscp }
::= { diffServDscpMarkActTable 1 }
DiffServDscpMarkActEntry ::= SEQUENCE {
diffServDscpMarkActDscp Dscp
}
diffServDscpMarkActDscp OBJECT-TYPE
SYNTAX Dscp
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The DSCP that this Action will store into the DSCP field of the
subject. It is quite possible that the only packets subject to
this Action are already marked with this DSCP. Note also that
Differentiated Services processing may result in packet being
marked on both ingress to a network and on egress from it, and
that ingress and egress can occur in the same router."
::= { diffServDscpMarkActEntry 1 }
--
-- Count Action Table
--
-- Because the MIB structure allows multiple cascading
-- diffServActionEntry be used to describe multiple actions for a data
-- path, the counter became an optional action type. In normal
-- implementation, either a data path has counters or it does not, as
-- opposed to being configurable. The management entity may choose to
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RFC 3289 Differentiated Services MIB May 2002
-- read the counter or not. Hence it is recommended for implementation
-- that have counters to always configure the count action as the first
-- of multiple actions.
--
diffServCountActNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for
diffServCountActId, or a zero to indicate that none exist."
::= { diffServAction 4 }
diffServCountActTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServCountActEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains counters for all the traffic passing through
an action element."
::= { diffServAction 5 }
diffServCountActEntry OBJECT-TYPE
SYNTAX DiffServCountActEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the count action table describes a single set of
traffic counters."
INDEX { diffServCountActId }
::= { diffServCountActTable 1 }
DiffServCountActEntry ::= SEQUENCE {
diffServCountActId IndexInteger,
diffServCountActOctets Counter64,
diffServCountActPkts Counter64,
diffServCountActStorage StorageType,
diffServCountActStatus RowStatus
}
diffServCountActId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Count Action entries. Managers
obtain new values for row creation in this table by reading
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RFC 3289 Differentiated Services MIB May 2002
diffServCountActNextFree."
::= { diffServCountActEntry 1 }
diffServCountActOctets OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets at the Action data path element.
Discontinuities in the value of this counter can occur at re-
initialization of the management system and at other times as
indicated by the value of ifCounterDiscontinuityTime on the
relevant interface."
::= { diffServCountActEntry 2 }
diffServCountActPkts OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of packets at the Action data path element.
Discontinuities in the value of this counter can occur at re-
initialization of the management system and at other times as
indicated by the value of ifCounterDiscontinuityTime on the
relevant interface."
::= { diffServCountActEntry 3 }
diffServCountActStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServCountActEntry 4 }
diffServCountActStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
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RFC 3289 Differentiated Services MIB May 2002
to it results in destruction being delayed until the row is no
longer used."
::= { diffServCountActEntry 5 }
--
-- Algorithmic Drop Table
--
diffServAlgDrop OBJECT IDENTIFIER ::= { diffServMIBObjects 6 }
diffServAlgDropNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServAlgDropId, or a
zero to indicate that none exist."
::= { diffServAlgDrop 1 }
diffServAlgDropTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServAlgDropEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The algorithmic drop table contains entries describing an
element that drops packets according to some algorithm."
::= { diffServAlgDrop 2 }
diffServAlgDropEntry OBJECT-TYPE
SYNTAX DiffServAlgDropEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry describes a process that drops packets according to
some algorithm. Further details of the algorithm type are to be
found in diffServAlgDropType and with more detail parameter entry
pointed to by diffServAlgDropSpecific when necessary."
INDEX { diffServAlgDropId }
::= { diffServAlgDropTable 1 }
DiffServAlgDropEntry ::= SEQUENCE {
diffServAlgDropId IndexInteger,
diffServAlgDropType INTEGER,
diffServAlgDropNext RowPointer,
diffServAlgDropQMeasure RowPointer,
diffServAlgDropQThreshold Unsigned32,
diffServAlgDropSpecific RowPointer,
diffServAlgDropOctets Counter64,
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RFC 3289 Differentiated Services MIB May 2002
diffServAlgDropPkts Counter64,
diffServAlgRandomDropOctets Counter64,
diffServAlgRandomDropPkts Counter64,
diffServAlgDropStorage StorageType,
diffServAlgDropStatus RowStatus
}
diffServAlgDropId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Algorithmic Dropper entries.
Managers obtain new values for row creation in this table by
reading diffServAlgDropNextFree."
::= { diffServAlgDropEntry 1 }
diffServAlgDropType OBJECT-TYPE
SYNTAX INTEGER {
other(1),
tailDrop(2),
headDrop(3),
randomDrop(4),
alwaysDrop(5)
}
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The type of algorithm used by this dropper. The value other(1)
requires further specification in some other MIB module.
In the tailDrop(2) algorithm, diffServAlgDropQThreshold
represents the maximum depth of the queue, pointed to by
diffServAlgDropQMeasure, beyond which all newly arriving packets
will be dropped.
In the headDrop(3) algorithm, if a packet arrives when the
current depth of the queue, pointed to by
diffServAlgDropQMeasure, is at diffServAlgDropQThreshold, packets
currently at the head of the queue are dropped to make room for
the new packet to be enqueued at the tail of the queue.
In the randomDrop(4) algorithm, on packet arrival, an Active
Queue Management algorithm is executed which may randomly drop a
packet. This algorithm may be proprietary, and it may drop either
the arriving packet or another packet in the queue.
diffServAlgDropSpecific points to a diffServRandomDropEntry that
describes the algorithm. For this algorithm,
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RFC 3289 Differentiated Services MIB May 2002
diffServAlgDropQThreshold is understood to be the absolute
maximum size of the queue and additional parameters are described
in diffServRandomDropTable.
The alwaysDrop(5) algorithm is as its name specifies; always
drop. In this case, the other configuration values in this Entry
are not meaningful; There is no useful 'next' processing step,
there is no queue, and parameters describing the queue are not
useful. Therefore, diffServAlgDropNext, diffServAlgDropMeasure,
and diffServAlgDropSpecific are all zeroDotZero."
::= { diffServAlgDropEntry 2 }
diffServAlgDropNext OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This selects the next Differentiated Services Functional Data
Path Element to handle traffic for this data path. This
RowPointer should point to an instance of one of:
diffServClfrEntry
diffServMeterEntry
diffServActionEntry
diffServQEntry
A value of zeroDotZero in this attribute indicates no further
Differentiated Services treatment is performed on traffic of this
data path. The use of zeroDotZero is the normal usage for the
last functional data path element of the current data path.
When diffServAlgDropType is alwaysDrop(5), this object is
ignored.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServAlgDropEntry 3 }
diffServAlgDropQMeasure OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Points to an entry in the diffServQTable to indicate the queue
that a drop algorithm is to monitor when deciding whether to drop
a packet. If the row pointed to does not exist, the algorithmic
dropper element is considered inactive.
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Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServAlgDropEntry 4 }
diffServAlgDropQThreshold OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "Bytes"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"A threshold on the depth in bytes of the queue being measured at
which a trigger is generated to the dropping algorithm, unless
diffServAlgDropType is alwaysDrop(5) where this object is
ignored.
For the tailDrop(2) or headDrop(3) algorithms, this represents
the depth of the queue, pointed to by diffServAlgDropQMeasure, at
which the drop action will take place. Other algorithms will need
to define their own semantics for this threshold."
::= { diffServAlgDropEntry 5 }
diffServAlgDropSpecific OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"Points to a table entry that provides further detail regarding a
drop algorithm.
Entries with diffServAlgDropType equal to other(1) may have this
point to a table defined in another MIB module.
Entries with diffServAlgDropType equal to randomDrop(4) must have
this point to an entry in diffServRandomDropTable.
For all other algorithms specified in this MIB, this should take
the value zeroDotZero.
The diffServAlgDropType is authoritative for the type of the drop
algorithm and the specific parameters for the drop algorithm
needs to be evaluated based on the diffServAlgDropType.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
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::= { diffServAlgDropEntry 6 }
diffServAlgDropOctets OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets that have been deterministically dropped by
this drop process.
Discontinuities in the value of this counter can occur at re-
initialization of the management system and at other times as
indicated by the value of ifCounterDiscontinuityTime on the
relevant interface."
::= { diffServAlgDropEntry 7 }
diffServAlgDropPkts OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of packets that have been deterministically dropped
by this drop process.
Discontinuities in the value of this counter can occur at re-
initialization of the management system and at other times as
indicated by the value of ifCounterDiscontinuityTime on the
relevant interface."
::= { diffServAlgDropEntry 8 }
diffServAlgRandomDropOctets OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets that have been randomly dropped by this
drop process. This counter applies, therefore, only to random
droppers.
Discontinuities in the value of this counter can occur at re-
initialization of the management system and at other times as
indicated by the value of ifCounterDiscontinuityTime on the
relevant interface."
::= { diffServAlgDropEntry 9 }
diffServAlgRandomDropPkts OBJECT-TYPE
SYNTAX Counter64
MAX-ACCESS read-only
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RFC 3289 Differentiated Services MIB May 2002
STATUS current
DESCRIPTION
"The number of packets that have been randomly dropped by this
drop process. This counter applies, therefore, only to random
droppers.
Discontinuities in the value of this counter can occur at re-
initialization of the management system and at other times as
indicated by the value of ifCounterDiscontinuityTime on the
relevant interface."
::= { diffServAlgDropEntry 10 }
diffServAlgDropStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServAlgDropEntry 11 }
diffServAlgDropStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServAlgDropEntry 12 }
--
-- Random Drop Table
--
diffServRandomDropNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServRandomDropId,
or a zero to indicate that none exist."
::= { diffServAlgDrop 3 }
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diffServRandomDropTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServRandomDropEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The random drop table contains entries describing a process that
drops packets randomly. Entries in this table are pointed to by
diffServAlgDropSpecific."
::= { diffServAlgDrop 4 }
diffServRandomDropEntry OBJECT-TYPE
SYNTAX DiffServRandomDropEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry describes a process that drops packets according to a
random algorithm."
INDEX { diffServRandomDropId }
::= { diffServRandomDropTable 1 }
DiffServRandomDropEntry ::= SEQUENCE {
diffServRandomDropId IndexInteger,
diffServRandomDropMinThreshBytes Unsigned32,
diffServRandomDropMinThreshPkts Unsigned32,
diffServRandomDropMaxThreshBytes Unsigned32,
diffServRandomDropMaxThreshPkts Unsigned32,
diffServRandomDropProbMax Unsigned32,
diffServRandomDropWeight Unsigned32,
diffServRandomDropSamplingRate Unsigned32,
diffServRandomDropStorage StorageType,
diffServRandomDropStatus RowStatus
}
diffServRandomDropId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Random Drop entries. Managers
obtain new values for row creation in this table by reading
diffServRandomDropNextFree."
::= { diffServRandomDropEntry 1 }
diffServRandomDropMinThreshBytes OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "bytes"
MAX-ACCESS read-create
STATUS current
Baker, et. al. Standards Track [Page 73]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"The average queue depth in bytes, beyond which traffic has a
non-zero probability of being dropped. Changes in this variable
may or may not be reflected in the reported value of
diffServRandomDropMinThreshPkts."
::= { diffServRandomDropEntry 2 }
diffServRandomDropMinThreshPkts OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "packets"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The average queue depth in packets, beyond which traffic has a
non-zero probability of being dropped. Changes in this variable
may or may not be reflected in the reported value of
diffServRandomDropMinThreshBytes."
::= { diffServRandomDropEntry 3 }
diffServRandomDropMaxThreshBytes OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "bytes"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The average queue depth beyond which traffic has a probability
indicated by diffServRandomDropProbMax of being dropped or
marked. Note that this differs from the physical queue limit,
which is stored in diffServAlgDropQThreshold. Changes in this
variable may or may not be reflected in the reported value of
diffServRandomDropMaxThreshPkts."
::= { diffServRandomDropEntry 4 }
diffServRandomDropMaxThreshPkts OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "packets"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The average queue depth beyond which traffic has a probability
indicated by diffServRandomDropProbMax of being dropped or
marked. Note that this differs from the physical queue limit,
which is stored in diffServAlgDropQThreshold. Changes in this
variable may or may not be reflected in the reported value of
diffServRandomDropMaxThreshBytes."
::= { diffServRandomDropEntry 5 }
diffServRandomDropProbMax OBJECT-TYPE
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RFC 3289 Differentiated Services MIB May 2002
SYNTAX Unsigned32 (0..1000)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The worst case random drop probability, expressed in drops per
thousand packets.
For example, if in the worst case every arriving packet may be
dropped (100%) for a period, this has the value 1000.
Alternatively, if in the worst case only one percent (1%) of
traffic may be dropped, it has the value 10."
::= { diffServRandomDropEntry 6 }
diffServRandomDropWeight OBJECT-TYPE
SYNTAX Unsigned32 (0..65536)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The weighting of past history in affecting the Exponentially
Weighted Moving Average function that calculates the current
average queue depth. The equation uses
diffServRandomDropWeight/65536 as the coefficient for the new
sample in the equation, and (65536 -
diffServRandomDropWeight)/65536 as the coefficient of the old
value.
Implementations may limit the values of diffServRandomDropWeight
to a subset of the possible range of values, such as powers of
two. Doing this would facilitate implementation of the
Exponentially Weighted Moving Average using shift instructions or
registers."
::= { diffServRandomDropEntry 7 }
diffServRandomDropSamplingRate OBJECT-TYPE
SYNTAX Unsigned32 (0..1000000)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The number of times per second the queue is sampled for queue
average calculation. A value of zero is used to mean that the
queue is sampled approximately each time a packet is enqueued (or
dequeued)."
::= { diffServRandomDropEntry 8 }
diffServRandomDropStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
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RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServRandomDropEntry 9 }
diffServRandomDropStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServRandomDropEntry 10 }
--
-- Queue Table
--
diffServQueue OBJECT IDENTIFIER ::= { diffServMIBObjects 7 }
--
-- An entry of diffServQTable represents a FIFO queue Differentiated
-- Services Functional Data Path element as described in the Informal
-- Differentiated Services Model section 7.1.1. Note that the
-- specification of scheduling parameters for a queue as part of the
-- input to a scheduler functional data path element as described in
-- the Informal Differentiated Services Model section 7.1.2. This
-- allows building of hierarchical queuing/scheduling. A queue
-- therefore has these attributes:
--
-- 1. Which scheduler will service this queue, diffServQNext.
-- 2. How the scheduler will service this queue, with respect
-- to all the other queues the same scheduler needs to service,
-- diffServQMinRate.
--
-- Note that upstream Differentiated Services Functional Data Path
-- elements may point to a shared diffServQTable entry as described
-- in the Informal Differentiated Services Model section 7.1.1.
--
diffServQNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
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RFC 3289 Differentiated Services MIB May 2002
STATUS current
DESCRIPTION
"This object contains an unused value for diffServQId, or a zero
to indicate that none exist."
::= { diffServQueue 1 }
diffServQTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServQEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The Queue Table enumerates the individual queues. Note that the
MIB models queuing systems as composed of individual queues, one
per class of traffic, even though they may in fact be structured
as classes of traffic scheduled using a common calendar queue, or
in other ways."
::= { diffServQueue 2 }
diffServQEntry OBJECT-TYPE
SYNTAX DiffServQEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the Queue Table describes a single queue or class of
traffic."
INDEX { diffServQId }
::= { diffServQTable 1 }
DiffServQEntry ::= SEQUENCE {
diffServQId IndexInteger,
diffServQNext RowPointer,
diffServQMinRate RowPointer,
diffServQMaxRate RowPointer,
diffServQStorage StorageType,
diffServQStatus RowStatus
}
diffServQId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Queue entries. Managers obtain new
values for row creation in this table by reading
diffServQNextFree."
::= { diffServQEntry 1 }
diffServQNext OBJECT-TYPE
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RFC 3289 Differentiated Services MIB May 2002
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This selects the next Differentiated Services Scheduler. The
RowPointer must point to a diffServSchedulerEntry.
A value of zeroDotZero in this attribute indicates an incomplete
diffServQEntry instance. In such a case, the entry has no
operational effect, since it has no parameters to give it
meaning.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServQEntry 2 }
diffServQMinRate OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This RowPointer indicates the diffServMinRateEntry that the
scheduler, pointed to by diffServQNext, should use to service
this queue.
If the row pointed to is zeroDotZero, the minimum rate and
priority is unspecified.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServQEntry 3 }
diffServQMaxRate OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This RowPointer indicates the diffServMaxRateEntry that the
scheduler, pointed to by diffServQNext, should use to service
this queue.
If the row pointed to is zeroDotZero, the maximum rate is the
line speed of the interface.
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RFC 3289 Differentiated Services MIB May 2002
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
::= { diffServQEntry 4 }
diffServQStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServQEntry 5 }
diffServQStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServQEntry 6 }
--
-- Scheduler Table
--
diffServScheduler OBJECT IDENTIFIER ::= { diffServMIBObjects 8 }
--
-- A Scheduler Entry represents a packet scheduler, such as a priority
-- scheduler or a WFQ scheduler. It provides flexibility for multiple
-- scheduling algorithms, each servicing multiple queues, to be used on
-- the same logical/physical interface.
--
-- Note that upstream queues or schedulers specify several of the
-- scheduler's parameters. These must be properly specified if the
-- scheduler is to behave as expected.
--
-- The diffServSchedulerMaxRate attribute specifies the parameters when
-- a scheduler's output is sent to another scheduler. This is used in
-- building hierarchical queues or schedulers.
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RFC 3289 Differentiated Services MIB May 2002
--
-- More discussion of the scheduler functional data path element is in
-- the Informal Differentiated Services Model section 7.1.2.
--
diffServSchedulerNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServSchedulerId, or
a zero to indicate that none exist."
::= { diffServScheduler 1 }
diffServSchedulerTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServSchedulerEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The Scheduler Table enumerates packet schedulers. Multiple
scheduling algorithms can be used on a given data path, with each
algorithm described by one diffServSchedulerEntry."
::= { diffServScheduler 2 }
diffServSchedulerEntry OBJECT-TYPE
SYNTAX DiffServSchedulerEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the Scheduler Table describing a single instance of
a scheduling algorithm."
INDEX { diffServSchedulerId }
::= { diffServSchedulerTable 1 }
DiffServSchedulerEntry ::= SEQUENCE {
diffServSchedulerId IndexInteger,
diffServSchedulerNext RowPointer,
diffServSchedulerMethod AutonomousType,
diffServSchedulerMinRate RowPointer,
diffServSchedulerMaxRate RowPointer,
diffServSchedulerStorage StorageType,
diffServSchedulerStatus RowStatus
}
diffServSchedulerId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
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RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"An index that enumerates the Scheduler entries. Managers obtain
new values for row creation in this table by reading
diffServSchedulerNextFree."
::= { diffServSchedulerEntry 1 }
diffServSchedulerNext OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This selects the next Differentiated Services Functional Data
Path Element to handle traffic for this data path. This normally
is null (zeroDotZero), or points to a diffServSchedulerEntry or a
diffServQEntry.
However, this RowPointer may also point to an instance of:
diffServClfrEntry,
diffServMeterEntry,
diffServActionEntry,
diffServAlgDropEntry.
It would point another diffServSchedulerEntry when implementing
multiple scheduler methods for the same data path, such as having
one set of queues scheduled by WRR and that group participating
in a priority scheduling system in which other queues compete
with it in that way. It might also point to a second scheduler
in a hierarchical scheduling system.
If the row pointed to is zeroDotZero, no further Differentiated
Services treatment is performed on traffic of this data path.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
DEFVAL { zeroDotZero }
::= { diffServSchedulerEntry 2 }
diffServSchedulerMethod OBJECT-TYPE
SYNTAX AutonomousType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The scheduling algorithm used by this Scheduler. zeroDotZero
indicates that this is unknown. Standard values for generic
algorithms: diffServSchedulerPriority, diffServSchedulerWRR, and
diffServSchedulerWFQ are specified in this MIB; additional values
Baker, et. al. Standards Track [Page 81]
RFC 3289 Differentiated Services MIB May 2002
may be further specified in other MIBs."
::= { diffServSchedulerEntry 3 }
diffServSchedulerMinRate OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This RowPointer indicates the entry in diffServMinRateTable
which indicates the priority or minimum output rate from this
scheduler. This attribute is used only when there is more than
one level of scheduler.
When it has the value zeroDotZero, it indicates that no minimum
rate or priority is imposed.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
DEFVAL { zeroDotZero }
::= { diffServSchedulerEntry 4 }
diffServSchedulerMaxRate OBJECT-TYPE
SYNTAX RowPointer
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"This RowPointer indicates the entry in diffServMaxRateTable
which indicates the maximum output rate from this scheduler.
When more than one maximum rate applies (eg, when a multi-rate
shaper is in view), it points to the first of those rate entries.
This attribute is used only when there is more than one level of
scheduler.
When it has the value zeroDotZero, it indicates that no maximum
rate is imposed.
Setting this to point to a target that does not exist results in
an inconsistentValue error. If the row pointed to is removed or
becomes inactive by other means, the treatment is as if this
attribute contains a value of zeroDotZero."
DEFVAL { zeroDotZero }
::= { diffServSchedulerEntry 5 }
diffServSchedulerStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
Baker, et. al. Standards Track [Page 82]
RFC 3289 Differentiated Services MIB May 2002
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServSchedulerEntry 6 }
diffServSchedulerStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServSchedulerEntry 7 }
--
-- OIDs for diffServTBParamType definitions.
--
diffServSchedulers OBJECT IDENTIFIER ::= { diffServMIBAdmin 2 }
diffServSchedulerPriority OBJECT-IDENTITY
STATUS current
DESCRIPTION
"For use with diffServSchedulerMethod to indicate the Priority
scheduling method. This is defined as an algorithm in which the
presence of data in a queue or set of queues absolutely precludes
dequeue from another queue or set of queues of lower priority.
Note that attributes from diffServMinRateEntry of the
queues/schedulers feeding this scheduler are used when
determining the next packet to schedule."
::= { diffServSchedulers 1 }
diffServSchedulerWRR OBJECT-IDENTITY
STATUS current
DESCRIPTION
"For use with diffServSchedulerMethod to indicate the Weighted
Round Robin scheduling method, defined as any algorithm in which
a set of queues are visited in a fixed order, and varying amounts
of traffic are removed from each queue in turn to implement an
average output rate by class. Notice attributes from
diffServMinRateEntry of the queues/schedulers feeding this
scheduler are used when determining the next packet to schedule."
Baker, et. al. Standards Track [Page 83]
RFC 3289 Differentiated Services MIB May 2002
::= { diffServSchedulers 2 }
diffServSchedulerWFQ OBJECT-IDENTITY
STATUS current
DESCRIPTION
"For use with diffServSchedulerMethod to indicate the Weighted
Fair Queuing scheduling method, defined as any algorithm in which
a set of queues are conceptually visited in some order, to
implement an average output rate by class. Notice attributes from
diffServMinRateEntry of the queues/schedulers feeding this
scheduler are used when determining the next packet to schedule."
::= { diffServSchedulers 3 }
--
-- Minimum Rate Parameters Table
--
-- The parameters used by a scheduler for its inputs or outputs are
-- maintained separately from the Queue or Scheduler table entries for
-- reusability reasons and so that they may be used by both queues and
-- schedulers. This follows the approach for separation of data path
-- elements from parameterization that is used throughout this MIB.
-- Use of these Minimum Rate Parameter Table entries by Queues and
-- Schedulers allows the modeling of hierarchical scheduling systems.
--
-- Specifically, a Scheduler has one or more inputs and one output.
-- Any queue feeding a scheduler, or any scheduler which feeds a second
-- scheduler, might specify a minimum transfer rate by pointing to an
-- Minimum Rate Parameter Table entry.
--
-- The diffServMinRatePriority/Abs/Rel attributes are used as
-- parameters to the work-conserving portion of a scheduler:
-- "work-conserving" implies that the scheduler can continue to emit
-- data as long as there is data available at its input(s). This has
-- the effect of guaranteeing a certain priority relative to other
-- scheduler inputs and/or a certain minimum proportion of the
-- available output bandwidth. Properly configured, this means a
-- certain minimum rate, which may be exceeded should traffic be
-- available should there be spare bandwidth after all other classes
-- have had opportunities to consume their own minimum rates.
--
diffServMinRateNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServMinRateId, or a
zero to indicate that none exist."
Baker, et. al. Standards Track [Page 84]
RFC 3289 Differentiated Services MIB May 2002
::= { diffServScheduler 3 }
diffServMinRateTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServMinRateEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The Minimum Rate Parameters Table enumerates individual sets of
scheduling parameter that can be used/reused by Queues and
Schedulers."
::= { diffServScheduler 4 }
diffServMinRateEntry OBJECT-TYPE
SYNTAX DiffServMinRateEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the Minimum Rate Parameters Table describes a single
set of scheduling parameters for use by one or more queues or
schedulers."
INDEX { diffServMinRateId }
::= { diffServMinRateTable 1 }
DiffServMinRateEntry ::= SEQUENCE {
diffServMinRateId IndexInteger,
diffServMinRatePriority Unsigned32,
diffServMinRateAbsolute Unsigned32,
diffServMinRateRelative Unsigned32,
diffServMinRateStorage StorageType,
diffServMinRateStatus RowStatus
}
diffServMinRateId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Scheduler Parameter entries.
Managers obtain new values for row creation in this table by
reading diffServMinRateNextFree."
::= { diffServMinRateEntry 1 }
diffServMinRatePriority OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The priority of this input to the associated scheduler, relative
Baker, et. al. Standards Track [Page 85]
RFC 3289 Differentiated Services MIB May 2002
to the scheduler's other inputs. A queue or scheduler with a
larger numeric value will be served before another with a smaller
numeric value."
::= { diffServMinRateEntry 2 }
diffServMinRateAbsolute OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "kilobits per second"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The minimum absolute rate, in kilobits/sec, that a downstream
scheduler element should allocate to this queue. If the value is
zero, then there is effectively no minimum rate guarantee. If the
value is non-zero, the scheduler will assure the servicing of
this queue to at least this rate.
Note that this attribute value and that of
diffServMinRateRelative are coupled: changes to one will affect
the value of the other. They are linked by the following
equation, in that setting one will change the other:
diffServMinRateRelative =
(diffServMinRateAbsolute*1000000)/ifSpeed
or, if appropriate:
diffServMinRateRelative = diffServMinRateAbsolute/ifHighSpeed"
REFERENCE
"ifSpeed, ifHighSpeed, Interface MIB, RFC 2863"
::= { diffServMinRateEntry 3 }
diffServMinRateRelative OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The minimum rate that a downstream scheduler element should
allocate to this queue, relative to the maximum rate of the
interface as reported by ifSpeed or ifHighSpeed, in units of
1/1000 of 1. If the value is zero, then there is effectively no
minimum rate guarantee. If the value is non-zero, the scheduler
will assure the servicing of this queue to at least this rate.
Note that this attribute value and that of
diffServMinRateAbsolute are coupled: changes to one will affect
the value of the other. They are linked by the following
equation, in that setting one will change the other:
Baker, et. al. Standards Track [Page 86]
RFC 3289 Differentiated Services MIB May 2002
diffServMinRateRelative =
(diffServMinRateAbsolute*1000000)/ifSpeed
or, if appropriate:
diffServMinRateRelative = diffServMinRateAbsolute/ifHighSpeed"
REFERENCE
"ifSpeed, ifHighSpeed, Interface MIB, RFC 2863"
::= { diffServMinRateEntry 4 }
diffServMinRateStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServMinRateEntry 5 }
diffServMinRateStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServMinRateEntry 6 }
--
-- Maximum Rate Parameter Table
--
-- The parameters used by a scheduler for its inputs or outputs are
-- maintained separately from the Queue or Scheduler table entries for
-- reusability reasons and so that they may be used by both queues and
-- schedulers. This follows the approach for separation of data path
-- elements from parameterization that is used throughout this MIB.
-- Use of these Maximum Rate Parameter Table entries by Queues and
-- Schedulers allows the modeling of hierarchical scheduling systems.
--
-- Specifically, a Scheduler has one or more inputs and one output.
-- Any queue feeding a scheduler, or any scheduler which feeds a second
-- scheduler, might specify a maximum transfer rate by pointing to a
-- Maximum Rate Parameter Table entry. Multi-rate shapers, such as a
Baker, et. al. Standards Track [Page 87]
RFC 3289 Differentiated Services MIB May 2002
-- Dual Leaky Bucket algorithm, specify their rates using multiple
-- Maximum Rate Parameter Entries with the same diffServMaxRateId but
-- different diffServMaxRateLevels.
--
-- The diffServMaxRateLevel/Abs/Rel attributes are used as
-- parameters to the non-work-conserving portion of a scheduler:
-- non-work-conserving implies that the scheduler may sometimes not
-- emit a packet, even if there is data available at its input(s).
-- This has the effect of limiting the servicing of the queue/scheduler
-- input or output, in effect performing shaping of the packet stream
-- passing through the queue/scheduler, as described in the Informal
-- Differentiated Services Model section 7.2.
--
diffServMaxRateNextFree OBJECT-TYPE
SYNTAX IndexIntegerNextFree
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object contains an unused value for diffServMaxRateId, or a
zero to indicate that none exist."
::= { diffServScheduler 5 }
diffServMaxRateTable OBJECT-TYPE
SYNTAX SEQUENCE OF DiffServMaxRateEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"The Maximum Rate Parameter Table enumerates individual sets of
scheduling parameter that can be used/reused by Queues and
Schedulers."
::= { diffServScheduler 6 }
diffServMaxRateEntry OBJECT-TYPE
SYNTAX DiffServMaxRateEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An entry in the Maximum Rate Parameter Table describes a single
set of scheduling parameters for use by one or more queues or
schedulers."
INDEX { diffServMaxRateId, diffServMaxRateLevel }
::= { diffServMaxRateTable 1 }
DiffServMaxRateEntry ::= SEQUENCE {
diffServMaxRateId IndexInteger,
diffServMaxRateLevel Unsigned32,
diffServMaxRateAbsolute Unsigned32,
Baker, et. al. Standards Track [Page 88]
RFC 3289 Differentiated Services MIB May 2002
diffServMaxRateRelative Unsigned32,
diffServMaxRateThreshold BurstSize,
diffServMaxRateStorage StorageType,
diffServMaxRateStatus RowStatus
}
diffServMaxRateId OBJECT-TYPE
SYNTAX IndexInteger
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that enumerates the Maximum Rate Parameter entries.
Managers obtain new values for row creation in this table by
reading diffServMaxRateNextFree."
::= { diffServMaxRateEntry 1 }
diffServMaxRateLevel OBJECT-TYPE
SYNTAX Unsigned32 (1..32)
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"An index that indicates which level of a multi-rate shaper is
being given its parameters. A multi-rate shaper has some number
of rate levels. Frame Relay's dual rate specification refers to a
'committed' and an 'excess' rate; ATM's dual rate specification
refers to a 'mean' and a 'peak' rate. This table is generalized
to support an arbitrary number of rates. The committed or mean
rate is level 1, the peak rate (if any) is the highest level rate
configured, and if there are other rates they are distributed in
monotonically increasing order between them."
::= { diffServMaxRateEntry 2 }
diffServMaxRateAbsolute OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "kilobits per second"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The maximum rate in kilobits/sec that a downstream scheduler
element should allocate to this queue. If the value is zero, then
there is effectively no maximum rate limit and that the scheduler
should attempt to be work conserving for this queue. If the value
is non-zero, the scheduler will limit the servicing of this queue
to, at most, this rate in a non-work-conserving manner.
Note that this attribute value and that of
diffServMaxRateRelative are coupled: changes to one will affect
the value of the other. They are linked by the following
Baker, et. al. Standards Track [Page 89]
RFC 3289 Differentiated Services MIB May 2002
equation, in that setting one will change the other:
diffServMaxRateRelative =
(diffServMaxRateAbsolute*1000000)/ifSpeed
or, if appropriate:
diffServMaxRateRelative = diffServMaxRateAbsolute/ifHighSpeed"
REFERENCE
"ifSpeed, ifHighSpeed, Interface MIB, RFC 2863"
::= { diffServMaxRateEntry 3 }
diffServMaxRateRelative OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The maximum rate that a downstream scheduler element should
allocate to this queue, relative to the maximum rate of the
interface as reported by ifSpeed or ifHighSpeed, in units of
1/1000 of 1. If the value is zero, then there is effectively no
maximum rate limit and the scheduler should attempt to be work
conserving for this queue. If the value is non-zero, the
scheduler will limit the servicing of this queue to, at most,
this rate in a non-work-conserving manner.
Note that this attribute value and that of
diffServMaxRateAbsolute are coupled: changes to one will affect
the value of the other. They are linked by the following
equation, in that setting one will change the other:
diffServMaxRateRelative =
(diffServMaxRateAbsolute*1000000)/ifSpeed
or, if appropriate:
diffServMaxRateRelative = diffServMaxRateAbsolute/ifHighSpeed"
REFERENCE
"ifSpeed, ifHighSpeed, Interface MIB, RFC 2863"
::= { diffServMaxRateEntry 4 }
diffServMaxRateThreshold OBJECT-TYPE
SYNTAX BurstSize
UNITS "Bytes"
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The number of bytes of queue depth at which the rate of a
Baker, et. al. Standards Track [Page 90]
RFC 3289 Differentiated Services MIB May 2002
multi-rate scheduler will increase to the next output rate. In
the last conceptual row for such a shaper, this threshold is
ignored and by convention is zero."
REFERENCE
"Adaptive rate Shaper, RFC 2963"
::= { diffServMaxRateEntry 5 }
diffServMaxRateStorage OBJECT-TYPE
SYNTAX StorageType
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The storage type for this conceptual row. Conceptual rows
having the value 'permanent' need not allow write-access to any
columnar objects in the row."
DEFVAL { nonVolatile }
::= { diffServMaxRateEntry 6 }
diffServMaxRateStatus OBJECT-TYPE
SYNTAX RowStatus
MAX-ACCESS read-create
STATUS current
DESCRIPTION
"The status of this conceptual row. All writable objects in this
row may be modified at any time. Setting this variable to
'destroy' when the MIB contains one or more RowPointers pointing
to it results in destruction being delayed until the row is no
longer used."
::= { diffServMaxRateEntry 7 }
--
-- MIB Compliance statements.
--
diffServMIBCompliances OBJECT IDENTIFIER ::=
{ diffServMIBConformance 1 }
diffServMIBGroups OBJECT IDENTIFIER ::=
{ diffServMIBConformance 2 }
diffServMIBFullCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"When this MIB is implemented with support for read-create, then
such an implementation can claim full compliance. Such devices
can then be both monitored and configured with this MIB."
MODULE IF-MIB -- The interfaces MIB, RFC2863
MANDATORY-GROUPS {
Baker, et. al. Standards Track [Page 91]
RFC 3289 Differentiated Services MIB May 2002
ifCounterDiscontinuityGroup
}
MODULE -- This Module
MANDATORY-GROUPS {
diffServMIBDataPathGroup, diffServMIBClfrGroup,
diffServMIBClfrElementGroup, diffServMIBMultiFieldClfrGroup,
diffServMIBActionGroup, diffServMIBAlgDropGroup,
diffServMIBQGroup, diffServMIBSchedulerGroup,
diffServMIBMaxRateGroup, diffServMIBMinRateGroup,
diffServMIBCounterGroup
}
GROUP diffServMIBMeterGroup
DESCRIPTION
"This group is mandatory for devices that implement metering
functions."
GROUP diffServMIBTBParamGroup
DESCRIPTION
"This group is mandatory for devices that implement token-bucket
metering functions."
GROUP diffServMIBDscpMarkActGroup
DESCRIPTION
"This group is mandatory for devices that implement DSCP-Marking
functions."
GROUP diffServMIBRandomDropGroup
DESCRIPTION
"This group is mandatory for devices that implement Random Drop
functions."
OBJECT diffServDataPathStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServClfrStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServClfrElementStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
Baker, et. al. Standards Track [Page 92]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServMultiFieldClfrAddrType
SYNTAX InetAddressType { unknown(0), ipv4(1), ipv6(2) }
DESCRIPTION
"An implementation is only required to support IPv4 and IPv6
addresses."
OBJECT diffServMultiFieldClfrDstAddr
SYNTAX InetAddress (SIZE(0|4|16))
DESCRIPTION
"An implementation is only required to support IPv4 and globally
unique IPv6 addresses."
OBJECT diffServAlgDropStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServRandomDropStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServQStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServSchedulerStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServMinRateStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
DESCRIPTION
"Support for createAndWait and notInService is not required."
OBJECT diffServMaxRateStatus
SYNTAX RowStatus { active(1) }
WRITE-SYNTAX RowStatus { createAndGo(4), destroy(6) }
Baker, et. al. Standards Track [Page 93]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Support for createAndWait and notInService is not required."
::= { diffServMIBCompliances 1 }
--
-- Read-Only Compliance
--
diffServMIBReadOnlyCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"When this MIB is implemented without support for read-create
(i.e. in read-only mode), then such an implementation can claim
read-only compliance. Such a device can then be monitored but can
not be configured with this MIB."
MODULE IF-MIB -- The interfaces MIB, RFC2863
MANDATORY-GROUPS {
ifCounterDiscontinuityGroup
}
MODULE -- This Module
MANDATORY-GROUPS {
diffServMIBDataPathGroup, diffServMIBClfrGroup,
diffServMIBClfrElementGroup, diffServMIBMultiFieldClfrGroup,
diffServMIBActionGroup, diffServMIBAlgDropGroup,
diffServMIBQGroup, diffServMIBSchedulerGroup,
diffServMIBMaxRateGroup, diffServMIBMinRateGroup,
diffServMIBCounterGroup
}
GROUP diffServMIBMeterGroup
DESCRIPTION
"This group is mandatory for devices that implement metering
functions."
GROUP diffServMIBTBParamGroup
DESCRIPTION
"This group is mandatory for devices that implement token-bucket
metering functions."
GROUP diffServMIBDscpMarkActGroup
DESCRIPTION
"This group is mandatory for devices that implement DSCP-Marking
functions."
GROUP diffServMIBRandomDropGroup
Baker, et. al. Standards Track [Page 94]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"This group is mandatory for devices that implement Random Drop
functions."
OBJECT diffServDataPathStart
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServDataPathStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServDataPathStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServClfrNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object not needed when diffServClfrTable is implemented read-
only"
OBJECT diffServClfrStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServClfrStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServClfrElementNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object not needed when diffServClfrelementTable is implemented
read-only"
OBJECT diffServClfrElementPrecedence
MIN-ACCESS read-only
DESCRIPTION
Baker, et. al. Standards Track [Page 95]
RFC 3289 Differentiated Services MIB May 2002
"Write access is not required."
OBJECT diffServClfrElementNext
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServClfrElementSpecific
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServClfrElementStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServClfrElementStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServMultiFieldClfrNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServMultiFieldClfrTable is
implemented in read-only mode."
OBJECT diffServMultiFieldClfrAddrType
SYNTAX InetAddressType { unknown(0), ipv4(1), ipv6(2) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required. An implementation is only required
to support IPv4 and IPv6 addresses."
OBJECT diffServMultiFieldClfrDstAddr
SYNTAX InetAddress (SIZE(0|4|16))
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required. An implementation is only required
to support IPv4 and globally unique IPv6 addresses."
OBJECT diffServMultiFieldClfrDstPrefixLength
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
Baker, et. al. Standards Track [Page 96]
RFC 3289 Differentiated Services MIB May 2002
OBJECT diffServMultiFieldClfrSrcAddr
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required. An implementation is only required
to support IPv4 and globally unique IPv6 addresses."
OBJECT diffServMultiFieldClfrSrcPrefixLength
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrDscp
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrFlowId
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrProtocol
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrDstL4PortMin
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrDstL4PortMax
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrSrcL4PortMin
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrSrcL4PortMax
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrStorage
MIN-ACCESS read-only
Baker, et. al. Standards Track [Page 97]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Write access is not required."
OBJECT diffServMultiFieldClfrStatus
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, createAndWait and notInService
support is not required."
OBJECT diffServMeterNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServMultiFieldClfrTable is
implemented in read-only mode."
OBJECT diffServMeterSucceedNext
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMeterFailNext
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMeterSpecific
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMeterStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMeterStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServTBParamNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServTBParamTable is implemented in
read-only mode."
Baker, et. al. Standards Track [Page 98]
RFC 3289 Differentiated Services MIB May 2002
OBJECT diffServTBParamType
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServTBParamRate
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServTBParamBurstSize
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServTBParamInterval
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServTBParamStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServTBParamStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServActionNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServActionTable is implemented in
read-only mode."
OBJECT diffServActionInterface
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServActionNext
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
Baker, et. al. Standards Track [Page 99]
RFC 3289 Differentiated Services MIB May 2002
OBJECT diffServActionSpecific
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServActionStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServActionStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServCountActNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServCountActTable is implemented
in read-only mode."
OBJECT diffServCountActStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServCountActStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServAlgDropNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServAlgDropTable is implemented in
read-only mode."
OBJECT diffServAlgDropType
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServAlgDropNext
MIN-ACCESS read-only
Baker, et. al. Standards Track [Page 100]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Write access is not required."
OBJECT diffServAlgDropQMeasure
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServAlgDropQThreshold
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServAlgDropSpecific
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServAlgDropStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServAlgDropStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServRandomDropNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServRandomDropTable is implemented
in read-only mode."
OBJECT diffServRandomDropMinThreshBytes
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropMinThreshPkts
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropMaxThreshBytes
MIN-ACCESS read-only
Baker, et. al. Standards Track [Page 101]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropMaxThreshPkts
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropProbMax
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropWeight
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropSamplingRate
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServRandomDropStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServQNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServQTable is implemented in
read-only mode."
OBJECT diffServQNext
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServQMinRate
MIN-ACCESS read-only
Baker, et. al. Standards Track [Page 102]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Write access is not required."
OBJECT diffServQMaxRate
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServQStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServQStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServSchedulerNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServSchedulerTable is implemented
in read-only mode."
OBJECT diffServSchedulerNext
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServSchedulerMethod
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServSchedulerMinRate
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServSchedulerMaxRate
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServSchedulerStorage
MIN-ACCESS read-only
Baker, et. al. Standards Track [Page 103]
RFC 3289 Differentiated Services MIB May 2002
DESCRIPTION
"Write access is not required."
OBJECT diffServSchedulerStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServMinRateNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServMinRateTable is implemented in
read-only mode."
OBJECT diffServMinRatePriority
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMinRateAbsolute
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMinRateRelative
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMinRateStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMinRateStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
OBJECT diffServMaxRateNextFree
MIN-ACCESS not-accessible
DESCRIPTION
"Object is not needed when diffServMaxrateTable is implemented in
read-only mode."
Baker, et. al. Standards Track [Page 104]
RFC 3289 Differentiated Services MIB May 2002
OBJECT diffServMaxRateAbsolute
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMaxRateRelative
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMaxRateThreshold
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMaxRateStorage
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required."
OBJECT diffServMaxRateStatus
SYNTAX RowStatus { active(1) }
MIN-ACCESS read-only
DESCRIPTION
"Write access is not required, and active is the only status that
needs to be supported."
::= { diffServMIBCompliances 2 }
diffServMIBDataPathGroup OBJECT-GROUP
OBJECTS {
diffServDataPathStart, diffServDataPathStorage,
diffServDataPathStatus
}
STATUS current
DESCRIPTION
"The Data Path Group defines the MIB Objects that describe a
functional data path."
::= { diffServMIBGroups 1 }
diffServMIBClfrGroup OBJECT-GROUP
OBJECTS {
diffServClfrNextFree, diffServClfrStorage,
diffServClfrStatus
}
STATUS current
DESCRIPTION
"The Classifier Group defines the MIB Objects that describe the
Baker, et. al. Standards Track [Page 105]
RFC 3289 Differentiated Services MIB May 2002
list the starts of individual classifiers."
::= { diffServMIBGroups 2 }
diffServMIBClfrElementGroup OBJECT-GROUP
OBJECTS {
diffServClfrElementNextFree,
diffServClfrElementPrecedence, diffServClfrElementNext,
diffServClfrElementSpecific, diffServClfrElementStorage,
diffServClfrElementStatus
}
STATUS current
DESCRIPTION
"The Classifier Element Group defines the MIB Objects that
describe the classifier elements that make up a generic
classifier."
::= { diffServMIBGroups 3 }
diffServMIBMultiFieldClfrGroup OBJECT-GROUP
OBJECTS {
diffServMultiFieldClfrNextFree,
diffServMultiFieldClfrAddrType,
diffServMultiFieldClfrDstAddr,
diffServMultiFieldClfrDstPrefixLength,
diffServMultiFieldClfrFlowId,
diffServMultiFieldClfrSrcAddr,
diffServMultiFieldClfrSrcPrefixLength,
diffServMultiFieldClfrDscp,
diffServMultiFieldClfrProtocol,
diffServMultiFieldClfrDstL4PortMin,
diffServMultiFieldClfrDstL4PortMax,
diffServMultiFieldClfrSrcL4PortMin,
diffServMultiFieldClfrSrcL4PortMax,
diffServMultiFieldClfrStorage,
diffServMultiFieldClfrStatus
}
STATUS current
DESCRIPTION
"The Multi-field Classifier Group defines the MIB Objects that
describe a classifier element for matching on various fields of
an IP and upper-layer protocol header."
::= { diffServMIBGroups 4 }
diffServMIBMeterGroup OBJECT-GROUP
OBJECTS {
diffServMeterNextFree, diffServMeterSucceedNext,
diffServMeterFailNext, diffServMeterSpecific,
diffServMeterStorage, diffServMeterStatus
}
Baker, et. al. Standards Track [Page 106]
RFC 3289 Differentiated Services MIB May 2002
STATUS current
DESCRIPTION
"The Meter Group defines the objects used in describing a generic
meter element."
::= { diffServMIBGroups 5 }
diffServMIBTBParamGroup OBJECT-GROUP
OBJECTS {
diffServTBParamNextFree, diffServTBParamType,
diffServTBParamRate, diffServTBParamBurstSize,
diffServTBParamInterval, diffServTBParamStorage,
diffServTBParamStatus
}
STATUS current
DESCRIPTION
"The Token-Bucket Meter Group defines the objects used in
describing a token bucket meter element."
::= { diffServMIBGroups 6 }
diffServMIBActionGroup OBJECT-GROUP
OBJECTS {
diffServActionNextFree, diffServActionNext,
diffServActionSpecific, diffServActionStorage,
diffServActionInterface, diffServActionStatus
}
STATUS current
DESCRIPTION
"The Action Group defines the objects used in describing a
generic action element."
::= { diffServMIBGroups 7 }
diffServMIBDscpMarkActGroup OBJECT-GROUP
OBJECTS {
diffServDscpMarkActDscp
}
STATUS current
DESCRIPTION
"The DSCP Mark Action Group defines the objects used in
describing a DSCP Marking Action element."
::= { diffServMIBGroups 8 }
diffServMIBCounterGroup OBJECT-GROUP
OBJECTS {
diffServCountActOctets, diffServCountActPkts,
diffServAlgDropOctets, diffServAlgDropPkts,
diffServAlgRandomDropOctets, diffServAlgRandomDropPkts,
diffServCountActStorage, diffServCountActStatus,
diffServCountActNextFree
Baker, et. al. Standards Track [Page 107]
RFC 3289 Differentiated Services MIB May 2002
}
STATUS current
DESCRIPTION
"A collection of objects providing information specific to
packet-oriented network interfaces."
::= { diffServMIBGroups 9 }
diffServMIBAlgDropGroup OBJECT-GROUP
OBJECTS {
diffServAlgDropNextFree, diffServAlgDropType,
diffServAlgDropNext, diffServAlgDropQMeasure,
diffServAlgDropQThreshold, diffServAlgDropSpecific,
diffServAlgDropStorage, diffServAlgDropStatus
}
STATUS current
DESCRIPTION
"The Algorithmic Drop Group contains the objects that describe
algorithmic dropper operation and configuration."
::= { diffServMIBGroups 10 }
diffServMIBRandomDropGroup OBJECT-GROUP
OBJECTS {
diffServRandomDropNextFree,
diffServRandomDropMinThreshBytes,
diffServRandomDropMinThreshPkts,
diffServRandomDropMaxThreshBytes,
diffServRandomDropMaxThreshPkts,
diffServRandomDropProbMax,
diffServRandomDropWeight,
diffServRandomDropSamplingRate,
diffServRandomDropStorage,
diffServRandomDropStatus
}
STATUS current
DESCRIPTION
"The Random Drop Group augments the Algorithmic Drop Group for
random dropper operation and configuration."
::= { diffServMIBGroups 11 }
diffServMIBQGroup OBJECT-GROUP
OBJECTS {
diffServQNextFree, diffServQNext, diffServQMinRate,
diffServQMaxRate, diffServQStorage, diffServQStatus
}
STATUS current
DESCRIPTION
"The Queue Group contains the objects that describe an
Baker, et. al. Standards Track [Page 108]
RFC 3289 Differentiated Services MIB May 2002
interface's queues."
::= { diffServMIBGroups 12 }
diffServMIBSchedulerGroup OBJECT-GROUP
OBJECTS {
diffServSchedulerNextFree, diffServSchedulerNext,
diffServSchedulerMethod, diffServSchedulerMinRate,
diffServSchedulerMaxRate, diffServSchedulerStorage,
diffServSchedulerStatus
}
STATUS current
DESCRIPTION
"The Scheduler Group contains the objects that describe packet
schedulers on interfaces."
::= { diffServMIBGroups 13 }
diffServMIBMinRateGroup OBJECT-GROUP
OBJECTS {
diffServMinRateNextFree, diffServMinRatePriority,
diffServMinRateAbsolute, diffServMinRateRelative,
diffServMinRateStorage, diffServMinRateStatus
}
STATUS current
DESCRIPTION
"The Minimum Rate Parameter Group contains the objects that
describe packet schedulers' minimum rate or priority guarantees."
::= { diffServMIBGroups 14 }
diffServMIBMaxRateGroup OBJECT-GROUP
OBJECTS {
diffServMaxRateNextFree, diffServMaxRateAbsolute,
diffServMaxRateRelative, diffServMaxRateThreshold,
diffServMaxRateStorage, diffServMaxRateStatus
}
STATUS current
DESCRIPTION
"The Maximum Rate Parameter Group contains the objects that
describe packet schedulers' maximum rate guarantees."
::= { diffServMIBGroups 15 }
END
Baker, et. al. Standards Track [Page 109]
RFC 3289 Differentiated Services MIB May 2002
7. Acknowledgments
This MIB builds on all the work that has gone into the Informal
Management Model for Differentiated Services Routers, Differentiated
Services PIB, and Differentiated Services Policy MIB (SNMPCONF WG).
It has been developed with the active involvement of many people, but
most notably Yoram Bernet, Steve Blake, Brian Carpenter, Dave Durham,
Michael Fine, Victor Firoiu, Jeremy Greene, Dan Grossman, Roch
Guerin, Scott Hahn, Joel Halpern, Van Jacobsen, Keith McCloghrie, Bob
Moore, Kathleen Nichols, Ping Pan, Nabil Seddigh, John Seligson, and
Walter Weiss.
Juergen Schoenwaelder, Dave Perkins, Frank Strauss, Harrie
Hazewinkel, and Bert Wijnen are especially to be noted for review
comments on the structure and usage of the MIB for network management
purposes, and its compliance with SMIv2.
8. Security Considerations
It is clear that this MIB is potentially useful for configuration.
Anything that can be configured can be misconfigured, with
potentially disastrous effects.
At this writing, no security holes have been identified beyond those
that SNMP Security is itself intended to address. These relate
primarily to controlled access to sensitive information and the
ability to configure a device - or which might result from operator
error, which is beyond the scope of any security architecture.
There are many read-write and read-create management objects defined
in this MIB. Such objects are often sensitive or vulnerable in some
network environments. The support for SET operations in a non-secure
environment without proper protection can have a negative effect on
network operations. The use of SNMP Version 3 is recommended over
prior versions for configuration control as its security model is
improved.
There are a number of managed objects in this MIB that may contain
information that may be sensitive from a business perspective, in
that they may represent a customer's service contract or the filters
that the service provider chooses to apply to a customer's ingress or
egress traffic. There are no objects which are sensitive in their
own right, such as passwords or monetary amounts.
Baker, et. al. Standards Track [Page 110]
RFC 3289 Differentiated Services MIB May 2002
It may be important to even control GET access to these objects and
possibly to even encrypt the values of these objects when sending
them over the network via SNMP. Not all versions of SNMP provide
features for such a secure environment.
SNMPv1 by itself is not a secure environment. Even if the network
itself is secure (for example by using IPSec), even then, there is no
control as to who on the secure network is allowed to access and
GET/SET (read/change/create/delete) the objects in this MIB.
It is recommended that the implementors consider the security
features as provided by the SNMPv3 framework. Specifically, the use
of the User-based Security Model [RFC 2574] and the View-based Access
Control Model [RFC 2575] is recommended.
It is then a customer/user responsibility to ensure that the SNMP
entity giving access to an instance of this MIB, is properly
configured to give access to the objects only to those principals
(users) that have legitimate rights to indeed GET or SET
(change/create/delete) them.
9. Intellectual Property Rights
The IETF takes no position regarding the validity or scope of any
intellectual property or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights
might or might not be available; neither does it represent that it
has made any effort to identify any such rights. Information on the
IETF's procedures with respect to rights in standards-track and
standards-related documentation can be found in BCP-11. Copies of
claims of rights made available for publication and any assurances of
licenses to be made available, or the result of an attempt made to
obtain a general license or permission for the use of such
proprietary rights by implementors or users of this specification can
be obtained from the IETF Secretariat.
The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary
rights which may cover technology that may be required to practice
this standard. Please address the information to the IETF Executive
Director.
Baker, et. al. Standards Track [Page 111]
RFC 3289 Differentiated Services MIB May 2002
10. References
[RFC 2571] Harrington, D., Presuhn, R. and B. Wijnen, "An
Architecture for Describing SNMP Management
Frameworks", RFC 2571, April 1999.
[RFC 1155] Rose, M. and K. McCloghrie, "Structure and
Identification of Management Information for TCP/IP-
based Internets", STD 16, RFC 1155, May 1990.
[RFC 1212] Rose, M. and K. McCloghrie, "Concise MIB Definitions",
STD 16, RFC 1212, March 1991.
[RFC 1215] Rose, M., "A Convention for Defining Traps for use with
the SNMP", RFC 1215, March 1991.
[RFC 2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
J., Rose, M. and S. Waldbusser, "Structure of
Management Information Version 2 (SMIv2)", STD 58, RFC
2578, April 1999.
[RFC 2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
J., Rose, M. and S. Waldbusser, "Textual Conventions
for SMIv2", STD 58, RFC 2579, April 1999.
[RFC 2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case,
J., Rose, M. and S. Waldbusser, "Conformance Statements
for SMIv2", STD 58, RFC 2580, April 1999.
[RFC 1157] Case, J., Fedor, M., Schoffstall, M. and J. Davin,
"Simple Network Management Protocol", STD 15, RFC 1157,
May 1990.
[RFC 1901] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Introduction to Community-based SNMPv2", RFC 1901,
January 1996.
[RFC 1906] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Transport Mappings for Version 2 of the Simple Network
Management Protocol (SNMPv2)", RFC 1906, January 1996.
[RFC 2572] Case, J., Harrington D., Presuhn R. and B. Wijnen,
"Message Processing and Dispatching for the Simple
Network Management Protocol (SNMP)", RFC 2572, April
1999.
Baker, et. al. Standards Track [Page 112]
RFC 3289 Differentiated Services MIB May 2002
[RFC 2574] Blumenthal, U. and B. Wijnen, "User-based Security
Model (USM) for version 3 of the Simple Network
Management Protocol (SNMPv3)", RFC 2574, April 1999.
[RFC 1905] Case, J., McCloghrie, K., Rose, M. and S. Waldbusser,
"Protocol Operations for Version 2 of the Simple
Network Management Protocol (SNMPv2)", RFC 1905,
January 1996.
[RFC 2573] Levi, D., Meyer, P. and B. Stewart, "SNMP
Applications", RFC 2573, April 1999.
[RFC 2575] Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based
Access Control Model (VACM) for the Simple Network
Management Protocol (SNMP)", RFC 2575, April 1999.
[RFC 2570] Case, J., Mundy, R., Partain, D. and B. Stewart,
"Introduction to Version 3 of the Internet-standard
Network Management Framework", RFC 2570, April 1999.
[RFC 2119] Bradner, S., "Key words to use in the RFCs", BCP 14,
RFC 2119, March 1997.
[ACTQMGMT] V. Firoiu, M. Borden, "A Study of Active Queue
Management for Congestion Control", March 2000, In IEEE
Infocom 2000, http://www.ieee-
infocom.org/2000/papers/405.pdf
[AQMROUTER] V. Misra, W. Gong, D. Towsley, "Fluid-based analysis of
a network of AQM routers supporting TCP flows with an
application to RED", In SIGCOMM
2000,http://www.acm.org/sigcomm/sigcomm2000/conf/
paper/sigcomm2000-4-3.ps.gz
[AF-PHB] Heinanen, J., Baker, F., Weiss, W. and J. Wroclawski,
"Assured Forwarding PHB Group", RFC 2597, June 1999.
[DSARCH] Blake, S., Black, D., Carlson, M., Davies, E., Wang, Z.
and W. Weiss, "An Architecture for Differentiated
Service", RFC 2475, December 1998.
[DSFIELD] Nichols, K., Blake, S., Baker, F. and D. Black,
"Definition of the Differentiated Services Field (DS
Field) in the IPv4 and IPv6 Headers", RFC 2474,
December 1998.
Baker, et. al. Standards Track [Page 113]
RFC 3289 Differentiated Services MIB May 2002
[DSPIB] Fine, M., McCloghrie, K., Seligson, J., Chan, K., Hahn,
S. and A. Smith, "Differentiated Services Quality of
Service Policy Information Base", Work in Progress.
[DSTERMS] Grossman, D., "New Terminology for Differentiated
Services", RFC 3260, April 2002.
[EF-PHB] Jacobson, V., Nichols, K. and K. Poduri, "An Expedited
Forwarding PHB", RFC 3246, March 2002.
[IF-MIB] McCloghrie, K. and F. Kastenholz, "The Interfaces Group
MIB using SMIv2", RFC 2863, June 2000.
[INETADDRESS] Daniele, M., Haberman, B., Routhier, S. and J.
Schoenwaelder, "Textual Conventions for Internet
Network Addresses.", RFC 3291, May 2002.
[INTSERVMIB] Baker, F., Krawczyk, J. and A. Sastry, "Integrated
Services Management Information Base using SMIv2", RFC
2213, September 1997.
[MODEL] Bernet, Y., Blake, S., Smith, A. and D. Grossman, "An
Informal Management Model for Differentiated Services
Routers", Work in Progress.
[RED93] "Random Early Detection", 1993.
[srTCM] Heinanen, J. and R. Guerin, "A Single Rate Three Color
Marker", RFC 2697, September 1999.
[trTCM] Heinanen, J. and R. Guerin, "A Two Rate Three Color
Marker", RFC 2698, September 1999.
[TSWTCM] Fang, W., Seddigh, N. and B. Nandy, "A Time Sliding
Window Three Color Marker (TSWTCM)", RFC 2859, June
2000.
[SHAPER] Bonaventure, O. and S. De Cnodder, "A Rate Adaptive
Shaper for Differentiated Services", RFC 2963, October
2000.
Baker, et. al. Standards Track [Page 114]
RFC 3289 Differentiated Services MIB May 2002
11. Authors' Addresses
Fred Baker
Cisco Systems
1121 Via Del Rey
Santa Barbara, California 93117
EMail: fred@cisco.com
Kwok Ho Chan
Nortel Networks
600 Technology Park Drive
Billerica, MA 01821
EMail: khchan@nortelnetworks.com
Andrew Smith
Harbour Networks
Jiuling Building
21 North Xisanhuan Ave.
Beijing, 100089, PRC
EMail: ah_smith@acm.org
Baker, et. al. Standards Track [Page 115]
RFC 3289 Differentiated Services MIB May 2002
12. Full Copyright Statement
Copyright (C) The Internet Society (2002). All Rights Reserved.
This document and translations of it may be copied and furnished to
others, and derivative works that comment on or otherwise explain it
or assist in its implementation may be prepared, copied, published
and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
This document and the information contained herein is provided on an
"AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Acknowledgement
Funding for the RFC Editor function is currently provided by the
Internet Society.
Baker, et. al. Standards Track [Page 116]
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