Internet Engineering Task Force M. Fine
Diffserv Working Group Atheros Communications
Internet-Draft K. McCloghrie
draft-ietf-diffserv-pib-09.txt Cisco Systems
Expires December 2002 J. Seligson
K. Chan
Nortel Networks
S. Hahn
C. Bell
Intel
A. Smith
Harbour Networks
F. Reichmeyer
PFN
June 2002
Differentiated Services Quality of Service Policy Information Base
Status of this Memo
This document is an Internet-Draft and is in full conformance with
all provisions of Section 10 of [RFC2026].
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
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The list of current Internet-Drafts can be accessed at
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The list of Internet-Draft Shadow Directories can be accessed at
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This document is a product of the IETF's Differentiated Services
Working Group. Comments should be addressed to WG's mailing list at
diffserv@ietf.org. The charter for Diffserv may be found at
http://www.ietf.org/html.charters/diffserv-charter.html.
Copyright c The Internet Society (2002). All Rights Reserved.
Distribution of this memo is unlimited.
Abstract
This document describes a Policy Information Base (PIB) for a device
implementing the Differentiated Services Architecture. The
provisioning classes defined here provide policy control of
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resources implementing the Differentiated Services Architecture.
These provisioning classes can be used with other none
Differentiated Services provisioning classes (defined in other PIBs)
to provide for a comprehensive policy controlled mapping of service
requirement to device resource capability and usage.
Conventions used in this document
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].
Table of Contents
1. Glossary..........................................................3
2. Introduction......................................................3
3. Relationship to the Diffserv Informal Management Model............3
3.1. PIB Overview....................................................4
4. Structure of the PIB..............................................6
4.1. General Conventions.............................................6
4.2. DiffServ Data Paths.............................................6
4.2.1. Data Path PRC.................................................7
4.3. Classifiers.....................................................7
4.3.1. Classifier PRC................................................8
4.3.2. Classifier Element PRC.......................................9
4.4. Meters..........................................................9
4.4.1. Meter PRC.....................................................9
4.4.2. Token-Bucket Parameter PRC....................................9
4.5. Actions........................................................10
4.5.1. DSCP Mark Action PRC.........................................10
4.6. Queueing Elements..............................................10
4.6.1. Algorithmic Dropper PRC......................................10
4.6.2. Random Dropper PRC...........................................12
4.6.3. Queues and Schedulers........................................13
4.7. Specifying Device Capabilities.................................15
5. PIB Usage Example................................................16
5.1. Data Path Example..............................................16
5.2. Classifier and Classifier Element Example......................17
5.3. Meter Example..................................................19
5.4. Action Example.................................................19
5.5. Dropper Examples...............................................20
5.5.1. Tail Dropper Example.........................................20
5.5.2. Single Queue Random Dropper Example..........................21
5.5.3. Multiple Queue Random Dropper Example........................21
5.6. Queue and Scheduler Example....................................23
6. Summary of the DiffServ PIB......................................25
7. PIB Operational Overview.........................................26
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8. PIB Definition...................................................27
9. Acknowledgments.................................................89
10. Security Considerations.........................................89
11. Intellectual Property Considerations............................89
12. RFC Editor Considerations.......................................90
13. IANA Considerations.............................................90
14. Authors' Addresses..............................................90
15. Normative References............................................91
16. Full Copyright...................................................94
1. Glossary
PRC Provisioning Class. A type of policy data. See [POLTERM].
PRI Provisioning Instance. An instance of a PRC. See [POLTERM].
PIB Policy Information Base. The database of policy information.
See [POLTERM].
PDP Policy Decision Point. See [RAP-FRAMEWORK].
PEP Policy Enforcement Point. See [RAP-FRAMEWORK].
PRID Provisioning Instance Identifier. Uniquely identifies an
instance of a PRC.
2. Introduction
[SPPI] describes a structure for specifying policy information that
can then be transmitted to a network device for the purpose of
configuring policy at that device. The model underlying this
structure is one of well-defined provisioning classes and instances
of these classes residing in a virtual information store called the
Policy Information Base (PIB).
This document specifies a set of provisioning classes specifically
for configuring QoS Policy for Differentiated Services [DSARCH].
One way to provision policy is by means of the COPS protocol [COPS]
with the extensions for provisioning [COPS-PR]. This protocol
supports multiple clients, each of which may provision policy for a
specific policy domain such as QoS. The PRCs defined in this
DiffServ QoS PIB are intended for use by the COPS-PR QoS client
type. Furthermore, these PRCs are in addition to any other PIBs
that may be defined for the QoS client type in the future, as well
as the PRCs defined in the Framework PIB [FR-PIB].
3. Relationship to the Diffserv Informal Management Model
This PIB is designed according to the Differentiated Services
Informal Management Model documented in [MODEL]. The model describes
the way that ingress and egress interfaces of a 'n'-port router are
modeled. It describes the configuration and management of a Diffserv
interface in terms of a Traffic Conditioning Block (TCB) which
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contains, by definition, zero or more classifiers, meters, actions,
algorithmic droppers, queues and schedulers. These elements are
arranged according to the QoS policy being expressed, always in that
order. Traffic may be classified; 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. When the treatment for a given packet
must have any of those elements repeated in a way that breaks the
permitted sequence {classifier, meter, action, algorithmic dropper,
queue, scheduler}, this must be modeled by cascading multiple TCBs.
The PIB represents this cascade by following the "Next" attributes
of the various elements. They indicate what the next step in
Diffserv processing will be, whether it be a classifier, meter,
action, algorithmic dropper, queue, scheduler or a decision to now
forward a packet.
The PIB models the individual elements that make up the TCBs. 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 PIB itself and only mentioned
in the text for relating the PIB with the [MODEL]. The actual
distinguishing of which TCB a specific element is a part of is not
needed for the instrumentation of a device to support the
functionalities of DiffServ, but it is useful for conceptual
reasons. By not using the TCB concept, this PIB allows any grouping
of elements to construct TCBs, using rules indicated by the [MODEL].
This will minimize changes to this PIB if rules in [MODEL] change.
The notion of a Data Path is used in this PIB to indicate the
DiffServ processing a packet may experience. This Data Path is
distinguished based on the Role Combination, Capability Set, and the
Direction of the flow the packet is part of. A Data Path Table
Entry indicates the first of possibly multiple elements that will
apply DiffServ treatment to the packet.
3.1. PIB Overview
This PIB is structured based on the need to configure the sequential
DiffServ treatments being applied to a packet, and the
parameterization of these treatments. These two aspects of the
configuration are kept separate throughout the design of the PIB,
and are fulfilled using separate tables and data definitions.
In addition, the PIB includes tables describing the capabilities and
limitations of the device using a general extensible framework.
These tables are reported to the PDP and assist the PDP with the
configuration of functional elements that can be realized by the
device.
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This capabilities and limitations exchange allows a single or
multiple devices to support many different variations of a
functional datapath element. Allowing diverse methods of providing
a general functional datapath element.
In this PIB, the ingress and egress portions of a router are
configured independently but in the same manner. The difference is
distinguished by an attribute in a table describing the start of the
data path. Each interface performs some or all of the following
high-level functions:
- Classify each packet according to some set of rules.
- Determine whether the data stream the packet is part of is within
or outside its metering parameters.
- Perform a set of resulting actions such as counting and marking of
the traffic with a Differentiated Services Code Point (DSCP) as
defined in [DSFIELD].
- Apply appropriate drop policy, either simple or complex
algorithmic drop functionality.
- Enqueue the traffic for output in the appropriate queue, whose
scheduler may shape the traffic or simply forward it with some
minimum rate or maximum latency.
The PIB therefore contains the following elements:
Data Path Table
This describes the starting point of DiffServ data paths within a
single DiffServ device. This class describes interface role
combination and interface direction specific data paths.
Classifier Tables
A general extensible framework for specifying a group of filters.
Meter Tables
A general extensible framework and one example of a
parameterization table - TBParam table, applicable for Simple
Token Bucket Meter, Average Rate Meter, Single Rate Three Color
Meter, Two Rate Three Color Meter, and Sliding Window Three
Color Meter.
Action Tables
A general extensible framework and example of parameterization
tables for Mark action. The "multiplexer" and "null" actions
described in [MODEL] are accomplished implicitly by means of the
Prid structures of the other elements.
Algorithmic Dropper Tables
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A general extensible framework for describing the dropper
functional datapath element. This includes the absolute dropper
and other queue measurement dependent algorithmic droppers.
Queue and Scheduler Tables
A general extensible framework for parameterizing queuing and
scheduler systems. Notice Shaper is considered as a type of
scheduler and is included here.
Capabilities Tables
A general extensible framework for defining the capabilities and
limitations of the elements listed above. The capability tables
allow intelligent configuration of the elements by a PDP.
4. Structure of the PIB
4.1. General Conventions
The PIB consists of PRCs that represent functional elements in the
data path (e.g. classifiers, meters, actions), and classes that
specify parameters that apply to a certain type of functional
element (e.g. a Token Bucket meter or a Mark action). Parameters
are typically specified in a separate PRC to enable the use of
parameter classes by multiple policies.
Functional element PRCs use the Prid TC (defined in [SPPI]) to
indicate indirection. A Prid is an object identifier that is used
to specify an instance of a PRC in another table. A Prid is used to
point to parameter PRC that applies to a functional element, such as
which filter should be used for a classifier element. A Prid is also
used to specify an instance of a functional element PRC that
describes what treatment should be applied next for a packet in the
data path.
Note that the use of Prids to specify parameter PRCs allows the same
functional element PRC to be extended with a number of different
types of parameter PRC's. In addition, using Prids to indicate the
next functional datapath element allows the elements to be ordered
in any way.
4.2. DiffServ Data Paths
This part of the PIB provides instrumentation for connecting the
DiffServ Functional Elements within a single DiffServ device.
Please refer to the [MODEL] for discussions on the valid sequencing
and grouping of DiffServ Functional Elements. Given some basic
information, e.g. the interface capability, role combination and
direction, the first DiffServ Functional Element is determined.
Subsequent DiffServ Functional Elements are provided by the "Next"
pointer attribute of each entry of data path tables. A description
of how this "Next" pointer is used in each table is provided in
their respective DESCRIPTION clauses.
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4.2.1. Data Path PRC
The Data Path PRC provides the DiffServ treatment starting points
for all packets of this DiffServ device. Each instance of this PRC
specifies the interface capability, role combination and direction
for the packet flow. There should be at most two entries for each
(interface type, role combination, interface capability), one for
ingress and one for egress. Each instance provides the first
DiffServ Functional Element each packet at a specific interface
(identified by the roles assigned to the interface) traveling in a
specific relative direction should experience. Notice this class is
interface specific, with the use of interface type capability set
and RoleCombination. To indicate explicitly that there are no
Diffserv treatments for a particular interface type capability set,
role combination and direction, an instance of the Data Path PRC can
be created with zeroDotZero in the dsDataPathStart attribute. This
situation can also be indicated implicitly by not supplying an
instance of a Data Path PRC for that particular interface type
capability set, role combination and direction. The
explicit/implicit selection is up to the implementation. This means
that the PEP should perform normal IP device processing when
zeroDotZero is used in the dsDataPathStart attribute, or when the
entry does not exist. Normal IP device processing will depend on the
device; for example, this can be forwarding the packet.
Based on implementation experience of network devices where data
path functional elements are implemented in separate physical
processors or application specific integrated circuits, separated by
switch fabric, it seems that more complex notions of data path are
required within the network device to correlate the different
physically separate data path functional elements. For example,
ingress processing may have determined a specific ingress flow that
gets aggregated with other ingress flows at an egress data path
functional element. Some of the information determined at the
ingress data path functional element may need to be used by the
egress data path functional element. In numerous implementations,
such information has been carried by adding it to the frame/memory
block used to carry the flow within the network device; some
implementers have called such information a "preamble" or a "frame
descriptor". Different implementations use different formats for
such information. Initially one may think such information is
implementation details within the network device that does not need
to be exposed outside of the network device. But from Policy Control
point of view, such information will be very useful in determining
network resource usage feedback from the network device to the
policy server. This is accomplished by using the Internal Label
Marker and Filter PRCs defined in [FR-PIB].
4.3. Classifiers
The classifier and classifier element tables determine how traffic
is sorted out. They identify separable classes of traffic, by
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reference to appropriate filters, which may select anything from an
individual micro-flow to aggregates identified by DSCP.
The classification is used to send these separate streams to
appropriate Meter, Action, Algorithmic Dropper, Queue and Scheduler
elements. For example, to indicate a multi-stage meter, sub-classes
of traffic may be sent to different meter stages: e.g. in an
implementation of the Assured Forwarding (AF) PHB [AF-PHB], AF11
traffic might be sent to the first meter, AF12 traffic might be sent
to the second and AF13 traffic sent to the second meter stage's out-
of-profile action.
The concept of a classifier is the same as described in [MODEL].
The structure of the classifier and classifier element tables, is
the same as the classifier described in [MODEL]. Classifier
elements have an associated precedence order solely for the purpose
of resolving ambiguity between overlapping filters. Filter with
higher values of precedence are compared first; the order of tests
for entries of the same precedence is unimportant.
A datapath may consist of more than one classifier. There may be
overlap of filter specification between filters of different
classifiers. The first classifier functional datapath element
encountered, as determined by the sequencing of diffserv functional
datapath elements, will be used first.
An important form of classifier is "everything else": the final
stage of the classifier i.e. the one with the lowest precedence,
must be "complete" since the result of an incomplete classifier is
not necessarily deterministic - see [MODEL] section 4.1.2.
When a classifier PRC is instantiated at the PEP, it should always
have at least one classifier element table entry, the "everything
else" classifier element, with its filter matching all IP packets.
This "everything else" classifier element should be created by the
PDP as part of the classifier setup. The PDP have full control of
all classifier PRIs instantiated at the PEP.
The definition of the actual filter to be used by the classifier is
referenced via a Prid: this enables the use of any sort of filter
table that one might wish to design, standard or proprietary. No
filters are defined in this PIB. However, standard filters for IP
packets are defined in the Framework PIB [FR-PIB].
4.3.1. Classifier PRC
Classifiers, used in various ingress and egress interfaces, are
organized by the instances of the Classifier PRC. A data path entry
points to a classifier entry. A classifier entry identifies a list
of classifier elements. A classifier element effectively includes
the filter entry, and points to a "next" classifier entry or other
data path functional element.
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4.3.2. Classifier Element PRC
Classifier elements point to the filters which identify various
classes of traffic. The separation between the "classifier element"
and the "filter" allows us to use many different kinds of filters
with the same essential semantics of "an identified set of traffic".
The traffic matching the filter corresponding to a classifier
element is given to the "next" data path functional element
identified in the classifier element.
An example of a filter that may be pointed to by a Classifier
Element PRI is the frwkIpFilter PRC, defined in [FR-PIB].
4.4. Meters
A meter, according to [MODEL] section 5, measures the rate at which
packets making up a stream of traffic pass it, compares this rate to
some set of thresholds and produces some number (two or more) of
potential results. A given packet is said to "conform" to the meter
if, at the time that the packet is being looked at, the stream
appears to be within the meter's profile. PIB syntax makes it
easiest to define this as a sequence of one or more cascaded
pass/fail tests, modeled here as if-then-else constructs. It is
important to understand that this way of modeling does not imply
anything about the implementation being "sequential": multi-
rate/multi-profile meters e.g. those designed to support [SRTCM],
[TRTCM], or [TSWTCM] can still be modeled this way even if they, of
necessity, share information between the stages: the stages are
introduced merely as a notational convenience in order to simplify
the PIB structure.
4.4.1. Meter PRC
The generic meter PRC is used as a base for all more specific forms
of meter. The definition of parameters specific to the type of
meter used is referenced via a pointer to an instance of a PRC
containing those specifics. This enables the use of any sort of
specific meter table that one might wish to design, standard or
proprietary. One specific meter table is defined in this PIB module.
Other meter tables may be defined in other PIB modules.
4.4.2. Token-Bucket Parameter PRC
This is included as an example of a common type of meter. Entries
in this class are referenced from the dsMeterSpecific attributes of
meter PRC instances. The parameters are represented by a rate
dsTBParamRate, a burst size dsTBParamBurstSize, and an interval
dsTBparamInterval. The type of meter being parameterized is
indicated by the dsTBParamType attribute. This is used to determine
how the rate, burst and rate interval parameters are used.
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Additional meter parameterization classes can be defined in other
PIBs when necessary.
4.5. Actions
Actions include "no action", "mark the traffic with a DSCP" or
"specific action". Other tasks such as "shape the traffic" or "drop
based on some algorithm" are handled in other functional datapath
elements rather than in actions. The "multiplexer", "replicator"
and "null" actions described in [MODEL] are accomplished implicitly
through various combinations of the other elements.
This PIB uses the Action PRC dsActionTable to organize one Action's
relationship with the element(s) before and after it. It allows
Actions to be cascaded to enable multiple Actions be applied to a
single traffic stream by using each entry's dsActionNext attribute.
The dsActionNext attribute of the last action entry in the chain
points to the next element in the TCB, if any, e.g. a Queueing
element. It may also point at a next TCB.
The parameters needed for the Action element will depend on the type
of Action to be taken. Hence the PIB allows for specific Action
Tables for the different Action types. This flexibility allows
additional Actions be specified in other PIBs and also allows for
the use of proprietary Actions without impact on those defined here.
One may consider packet dropping as an Action element. Packet
dropping is handled by the Algorithmic Dropper datapath functional
element.
4.5.1. DSCP Mark Action PRC
This Action is applied to traffic in order to mark it with a
Diffserv Codepoint (DSCP) value, specified in the
dsDscpMarkActTable.
4.6. Queueing Elements
These include Algorithmic Droppers, Queues and Schedulers, which are
all inter-related in their use of queueing techniques.
4.6.1. Algorithmic Dropper PRC
Algorithmic Droppers are represented in this PIB by instances of the
Algorithmic Dropper PRC. An Algorithmic Dropper is assumed to
operate indiscriminately on all packets that are presented at its
input, all traffic separation should be done by classifiers and
meters preceding it.
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Algorithmic Dropper includes many types of droppers, from the simple
always dropper to the more complex random dropper. This is
indicated by the dsAlgDropType attribute.
Algorithmic Droppers have a close relationship with queuing, each
Algorithmic Dropper Table entry contains a dsAlgDropQMeasure
attribute, indicating which queue's state affects the calculation of
the Algorithmic Dropper. Each entry also contains a dsAlgDropNext
attribute which indicates to which queue the Algorithmic Dropper
sinks its traffic.
Algorithmic Droppers may also contain a pointer to specific detail
of the drop algorithm, dsAlgDropSpecific. This PIB defines the
detail for three drop algorithms: Tail Drop, Head Drop and Random
Drop; other algorithms are outside the scope of this PIB module but
the general framework is intended to allow for their inclusion via
other PIB modules.
One generally-applicable parameter of a dropper is the specification
of a queue-depth threshold at which some drop action is to start.
This is represented in this PIB, as a base attribute,
dsAlgDropQThreshold, of the Algorithmic Dropper entry. The
attribute, dsAlgDropQMeasure, specifies which queue's depth
dsAlgDropQThreshold is to compare against.
o An Always Dropper drops every packet presented to it. This type
of dropper does not require any other parameter.
o A Tail Dropper requires the specification of a maximum queue
depth threshold: when the queue pointed at by dsAlgDropQMeasure
reaches that depth threshold, dsAlgDropQThresh, any new
traffic arriving at the dropper is discarded. This algorithm uses
only parameters that are part of the dsAlgDropEntry.
o A Head Dropper requires the specification of a maximum queue
depth threshold: when the queue pointed at by dsAlgDropQMeasure
reaches that depth threshold, dsAlgDropQThresh, traffic
currently at the head of the queue is discarded. This algorithm
uses only parameters that are part of the dsAlgDropEntry.
o Random Droppers are recommended as a way to control congestion,
in [QUEUEMGMT] and called for in the [AF-PHB]. Various
implementations exist, which agree on marking or dropping just
enough traffic to communicate with TCP-like protocols about
congestion avoidance, but differ markedly on their specific
parameters. This PIB attempts to offer a minimal set of controls
for any random dropper, but expects that vendors will augment the
PRC with additional controls and status in accordance with their
implementation. This algorithm requires additional parameters on
top of those in dsAlgDropEntry; these are discussed below.
A Dropper Type of other is provided for implementation of dropper
types not defined here. When the Dropper Type is other, its full
specification will need to be provided by another PRC referenced by
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dsAlgDropSpecific. A Dropper Type of Multiple Queue Random Dropper
is also provided, please reference section 5.5.3 of this document
for more details.
4.6.2. Random Dropper PRC
One example of a random dropper is a RED-like dropper. An example of
the representation chosen in this PIB 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 become 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 = Qmax.
In the PIB module, dsRandomDropMinThreshBytes and
dsRandomDropMinThreshPkts represent Qmin.
dsRandomDropMaxThreshBytes and dsRandomDropMaxThreshPkts represent
Qmax. dsAlgDropQThreshold represents Qclip. dsRandomDropProbMax
represents Pmax. This PIB 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 dsAlgDropQThreshold.
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.
+-----------------+ +-------+
|AlgDrop | |Queue |
--->| Next ---------+-+----------------->| Next -+-->
| QMeasure -------+-+ | ... |
| QThreshold | +-------+
| Type=randomDrop | +----------------+
| Specific -------+-->|RandomDrop |
+-----------------+ | MinThreshBytes |
| MaxThreshBytes |
| ProbMax |
| InvWeight |
| SamplingRate |
+----------------+
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Figure 1: Example Use of the RandomDropTable for Random Droppers
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 dsRandomDropWeight. The availability of
dsRandomDropSamplingRate as readable is important, the information
provided by Sampling Rate is essential to the configuration of
dsRandomDropWeight. 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 PIB module, e.g.
by using AUGMENTS on this class, to handle aspects of random drop
algorithms that are not standardized here.
NOTE: Deterministic Droppers can be viewed as a special case of
Random Droppers with the drop probability restricted to 0 and 1.
Hence Deterministic Droppers might be described by a Random Dropper
with Pmin = 0, Pmax = 1, Qmin = Qmax = Qclip, the averaged queue
length at which dropping occurs.
4.6.3. Queues and Schedulers
The Queue PRC models simple FIFO queues, as described in [MODEL]
section 7.1.1. The Scheduler PRC allows flexibility in constructing
both simple and somewhat more complex queueing hierarchies from
those queues. Of course, since TCBs can be cascaded multiple times
on an interface, even more complex hierarchies can be constructed
that way also.
Queue PRC instances are pointed at by the "next" attributes of the
upstream elements e.g. dsMeterSucceedNext. Note that multiple
upstream elements may direct their traffic to the same Queue PRI.
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. This would be represented by having
the dsMeterSucceedNext of each upstream meter point at the same
Queue PRI.
NOTE: Queue and Scheduler PRIs are for data path description, they
both use Scheduler Parameterization Table entries for diffserv
treatment parameterization.
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A Queue Table entry specifies the scheduler it wants service from by
use of its Next pointer.
Each Scheduler Table entry represents the algorithm in use for
servicing the one or more queues that feed it. The [MODEL] section
7.1.2 describes a scheduler with multiple inputs: this is
represented in the PIB by having the scheduling parameters be
associated with each input. In this way, sets of Queues can be
grouped together as inputs to the same Scheduler. This class serves
to represent the example scheduler described in the [MODEL]: other
more complex representations might be created outside of this PIB.
Both the Queue PRC and the Scheduler PRC use instances of the
Scheduler Parameterization PRC to specify diffserv treatment
parameterization. Scheduler Parameter PRC instances are used to
parameterize each input that feeds into a scheduler. The inputs can
be a mixture of Queue PRI's and Scheduler PRI's. Scheduler
Parameter PRI's can be used/reused by one or more Queue and/or
Scheduler Table entries.
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. A
higher-priority input which contains traffic that is not being
delayed for shaping will be serviced before a lower-priority input.
For Weighted Scheduling methods e.g. WFQ, WRR, the "weight" of a
given scheduler input is represented with a Minimum Service Rate
leaky-bucket profile which provides guaranteed minimum bandwidth to
that input, if required. This is represented by a rate
dsMinRateAbsolute; 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,
alternatively, be represented by a relative value, as a fraction of
the interface's current line rate, dsMinRateRelative 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.
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 control both queue service order
and amount of traffic serviced, providing meeting 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
dsMaxRateAbsolute; 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,
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alternatively, be represented by a relative value, as a fraction of
the interface's current line rate, dsMaxRateRelative. There was
discussion in the working group about alternative modeling
approaches, such as defining a shaping action or a shaping element.
We did not take this approach because shaping is in fact something a
scheduler does to its inputs, (which we model as a queue with a
maximum rate or a scheduler whose output has a maximum rate) and we
felt it was simpler and more elegant to simply describe it in that
context. Additionally, multi-rate shaper [SHAPER] can be
represented by the use of multiple dsMaxRateTable entries.
Other types of priority and weighted scheduling methods can be
defined using existing parameters in dsMinRateEntry. NOTE:
dsSchedulerMethod uses AutonomousType syntax, with the different
types of scheduling methods defined as OBJECT-IDENTITY. Future
scheduling methods may be defined in other PIBs. This requires an
OBJECT-IDENTITY definition, a description of how the existing
objects are reused, if they are, and any new objects they require.
NOTE: hierarchical schedulers can be parameterized using this PIB by
having Scheduler Table entries feeds into Scheduler Table entry.
4.7. Specifying Device Capabilities
The Diffserv PIB uses the Base PRC classes frwkPrcSupportTable and
frwkCompLimitsTable defined in [FR-PIB] to specify what PRC's are
supported by a PEP and to specify any limitations on that support.
The PIB also uses the capability PRC's frwkCapabilitySetTable and
frwkIfRoleComboTable defined in [FR-PIB] to specify the device's
capability sets, interface types and role combinations. Each
instance of the capability PRC frwkCapabilitySetTable contains an
OID that points to an instance of a PRC that describes some
capability of that interface type. The Diffserv PIB defines several
of these capability PRCs, which assist the PDP with the
configuration of Diffserv functional elements that can be
implemented by the device. Each of these capability PRCs contains a
direction attribute that specifies the direction for which the
capability applies. This attribute is defined in a base capability
PRC, which is extended by each specific capability PRC.
Classification capabilities, which specify the information elements
the device can use to classify traffic, are reported using the
dsIfClassificationCaps PRC. Metering capabilities, which indicate
what the device can do with out-of-profile packets, are specified
using the dsIfMeteringCaps PRC. Scheduling capabilities, such as
the number of inputs supported, are reported using the
dsIfSchedulingCaps PRC. Algorithmic drop capabilities, such as the
types of algorithms supported, are reported using the
dsIfAlgDropCaps PRC. Queue capabilities, such as the maximum number
of queues, are reported using the dsIfQueueCaps PRC.
Maximum Rate capabilities, such as the maximum number of max rate
Levels, are reported using the dsIfMaxRateCaps PRC.
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Two PRC's are defined to allow specification of the element linkage
capabilities of the PEP. The dsIfElmDepthCaps PRC indicates the
maximum number of functional datapath elements that can be linked
consecutively in a datapath. The dsIfElmLinkCaps PRC indicates what
functional datapath elements may follow a specific type of element
in a datapath.
The capability reporting classes in the DiffServ and Framework PIB
are meant to allow the PEP to indicate some general guidelines about
what the device can do. They are intended to be an aid to the PDP
when it constructs policy for the PEP. These classes do not
necessarily allow the PEP to indicate every possible configuration
that it can or cannot support. If a PEP receives a policy that it
cannot implement, it must notify the PDP with a failure report.
Currently [COPS-PR] error handling mechanism as specified in
[COPS-PR] sections 4.4, 4.5, and 4.6 completely handles all known
error cases of this PIB, hence no additional methods and PRCs need
to be specified here.
5. PIB Usage Example
This section provides some examples on how the different table
entries of this PIB may be used together for a Diffserv Device. The
usage of each individual attribute is defined within the PIB module
itself. For the figures, all the PIB table entry and attribute names
are assumed to have "ds" as their first common initial part of the
name, with the table entry name assumed to be their second common
initial part of the name. "0.0" is being used to mean zeroDotZero.
And for Scheduler Method "= X" means "using the OID of
diffServSchedulerX".
5.1. Data Path Example
Notice Each entry of the DataPath table is used for a specific
interface type handling a flow in a specific direction for a
specific functional role-combination. For our example, we just
define one of such entry.
+---------------------+
|DataPath |
| CapSetName ="IfCap1"|
| Roles = "A+B" |
| IfDirection=Ingress | +---------+
| Start --------------+--->|Clfr |
+---------------------+ | Id=Dept |
+---------+
Figure 2: DataPath Usage Example
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In Figure 2, we are using IfCap1 to indicate interface type with
capability set 1 handling ingress flow for functional roles of
"A+B". We are using classifier for departments to lead us into
the Classifier Example below.
5.2. Classifier and Classifier Element Example
We want to show how a multilevel classifier can be built using the
classifier tables provided by this PIB. Notice we didn't go into
details of the filters because they are not defined by this PIB.
Continuing from the Data Path example from the previous section, let
say we want to perform the following classification functionality to
do flow separation based on department and application type:
if (Dept1) then take Dept1-action
{
if (Appl1) then take Dept1-Appl1-action.
if (Appl2) then take Dept1-Appl2-action.
if (Appl3) then take Dept1-Appl3-action.
}
if (Dept2) then take Dept2-action
{
if (Appl1) then take Dept2-Appl1-action.
if (Appl2) then take Dept2-Appl2-action.
if (Appl3) then take Dept2-Appl3-action.
}
if (Dept3) then take Dept3-action
{
if (Appl1) then take Dept3-Appl1-action.
if (Appl2) then take Dept3-Appl2-action.
if (Appl3) then take Dept3-Appl3-action.
}
The above classification logic is translated into PIB table entries
below, with two levels of classifications.
First for department:
+---------+
|Clfr |
| Id=Dept |
+---------+
+-------------+ +-----------+
|ClfrElement | +-->|Clfr |
| Id=Dept1 | | | Id=D1Appl |
| ClfrId=Dept | | +-----------+
| Preced=NA | |
| Next -------+--+ +------------+
| Specific ---+----->|Filter Dept1|
+-------------+ +------------+
+-------------+ +-----------+
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|ClfrElement | +-->|Clfr |
| Id=Dept2 | | | Id=D2Appl |
| ClfrId=Dept | | +-----------+
| Preced=NA | |
| Next -------+--+ +------------+
| Specific ---+----->|Filter Dept2|
+-------------+ +------------+
+-------------+ +-----------+
|ClfrElement | +-->|Clfr |
| Id=Dept3 | | | Id=D3Appl |
| ClfrId=Dept | | +-----------+
| Preced=NA | |
| Next -------+--+ +------------+
| Specific ---+----->|Filter Dept3|
+-------------+ +------------+
Second for application:
+-----------+
|Clfr |
| Id=D1Appl |
+-----------+
+---------------+ +--------------+
|ClfrElement | +----------------->|Meter |
| Id=D1Appl1 | | | Id=D1A1Rate1 |
| ClfrId=D1Appl | | | SucceedNext -+--->...
| Preced=NA | | | FailNext ----+--->...
| Next ---------+--+ +------------+ | Specific ----+--->...
| Specific -----+---->|Filter Appl1| +--------------+
+---------------+ +------------+
+---------------+ +--------------+
|ClfrElement | +----------------->|Meter |
| Id=D1Appl2 | | | Id=D1A2Rate1 |
| ClfrId=D1Appl | | | SucceedNext -+--->...
| Preced=NA | | | FailNext ----+--->...
| Next ---------+--+ +------------+ | Specific ----+--->...
| Specific -----+---->|Filter Appl2| +--------------+
+---------------+ +------------+
+---------------+ +--------------+
|ClfrElement | +----------------->|Meter |
| Id=D1Appl3 | | | Id=D1A3Rate1 |
| ClfrId=D1Appl | | | SucceedNext -+--->...
| Preced=NA | | | FailNext ----+--->...
| Next ---------+--+ +------------+ | Specific ----+--->...
| Specific -----+---->|Filter Appl3| +--------------+
+---------------+ +------------+
Figure 3: Classifier Usage Example
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The application classifiers for department 2 and 3 will be very much
like the application classifier for department 1 shown above.
Notice in this example, Filters for Appl1, Appl2, and Appl3 are
reusable across the application classifiers.
This classifier and classifier element example assumes the next
differentiated services functional datapath element is Meter and
lead us into the Meter Example section.
5.3. Meter Example
A single rate simple Meter may be easy to envision, hence we will do
a Two Rate Three Color [TRTCM] example, using two Meter table
entries and two TBParam table entries.
+--------------+ +---------+ +--------------+ +----------+
|Meter | +->|Action | +->| Meter | +->|Action |
| Id=D1A1Rate1 | | | Id=Green| | | Id=D1A1Rate2 | | | Id=Yellow|
| SucceedNext -+-+ +---------+ | | SucceedNext -+-+ +----------+
| FailNext ----+-----------------+ | FailNext ----+--+ +-------+
| Specific -+ | | Specific -+ | +->|Action |
+-----------+--+ +-----------+--+ | Id=Red|
| | +-------+
| +------------+ | +------------+
+->|TBMeter | +->|TBMeter |
| Type=TRTCM | | Type=TRTCM |
| Rate | | Rate |
| BurstSize | | BurstSize |
| Interval | | Interval |
+------------+ +------------+
Figure 4: Meter Usage Example
For [TRTCM], the first level TBMeter entry is used for Committed
Information Rate and Committed Burst Size Token Bucket, and the
second level TBMeter entry is used for Peak Information Rate and
Peak Burst Size Token Bucket.
The other meters needed for this example will depend on the service
class each classified flow uses. But their construction will be
similar to the example given here. The TBMeter table entries can be
shared by multiple Meter table entries.
In this example the differentiated services functional datapath
element following Meter is Action, detailed in the following
section.
5.4. Action Example
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Typically Mark Action will be used, we will continue using the
"Action, Id=Green" branch off the Meter example.
Recall this is the D1A1Rate1 SucceedNext branch, meaning the flow
belongs to Department 1 Application 1, within the committed rate and
burst size limits for this flow. We would like to Mark this flow
with a specific DSCP and also with a device internal label.
+-----------+ +-----------+ +--->AlgDropAF11
|Action | +----------------->|Action | |
| Next -----+--+ +------------+ | Next -----+--+ +-------------+
| Specific -+---->|DscpMarkAct | | Specific -+--->|ILabelMarker |
+-----------+ | Dscp=AF11 | +-----------+ | ILabel=D1A1 |
+------------+ +-------------+
Figure 5: Action Usage Example
This example uses the frwkILabelMarker PRC defined in [FR-PIB],
showing the device internal label being used to indicate the micro
flow that feeds into the aggregated AF flow. This device internal
label may be used for flow accounting purposes and/or other data
path treatments.
5.5. Dropper Examples
The Dropper examples below will continue from the Action example
above for AF11 flow. We will provide three different dropper
setups, from simple to complex. The examples below may include some
queuing structures, they are here only to show the relationship of
the droppers to queuing and are not complete. Queuing examples are
provided in later sections.
5.5.1. Tail Dropper Example
The Tail Dropper is one of the simplest. For this example we just
want to drop part of the flow that exceeds the queue's buffering
capacity, 2 Mbytes.
+--------------------+ +------+
|AlgDrop | +->|Q AF1 |
| Id=AF11 | | +------+
| Type=tailDrop | |
| Next --------------+-+--+
| QMeasure ----------+-+
| QThreshold=2Mbytes |
| Specific=0.0 |
+--------------------+
Figure 6: Tail Dropper Usage Example
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5.5.2. Single Queue Random Dropper Example
Use of Random Dropper will introduce the usage of dsRandomDropEntry
as in the example below.
+-----------------+ +------+
|AlgDrop | +->|Q AF1 |
| Id=AF11 | | +------+
| Type=randomDrop | |
| Next -----------+-+--+
| QMeasure -------+-+
| QThreshold | +----------------+
| Specific -------+-->|RandomDrop |
+-----------------+ | MinThreshBytes |
| MinThreshPkts |
| MaxThreshBytes |
| MaxThreshPkts |
| ProbMax |
| Weight |
| SamplingRate |
+----------------+
Figure 7: Single Queue Random Dropper Usage Example
Notice for Random Dropper, dsAlgDropQThreshold contains the maximum
average queue length, Qclip, for the queue being measured as
indicated by dsAlgDropQMeasure, the rest of the Random Dropper
parameters are specified by dsRandomDropEntry as referenced by
dsAlgDropSpecific. In this example, both dsAlgDropNext and
dsAlgDropQMeasure references the same queue. This is the simple
case but dsAlgDropQMeasure may reference another queue for PEP
implementation supporting this feature.
5.5.3. Multiple Queue Random Dropper Example
When network device implementation requires measuring multiple
queues for determining the behavior of a drop algorithm, the
existing PRCs defined in this PIB will be sufficient for the simple
case, as indicated by this example.
+-------------+ +------+
|AlgDrop | +----------------+-------------------+->|Q_AF1 |
| Id=AF11 | | | | +------+
| Type=mQDrop | | | |
| Next -------+-+ +------------+ | +------------+ |
| QMeasure ---+-->|MQAlgDrop | | +->|MQAlgDrop | |
| QThreshold | | Id=AF11A | | | | Id=AF11B | |
| Specific | | Type | | | | Type | |
+-------------+ | Next ------+-+ | | Next ------+-+
| ExceedNext +---+ | ExceedNext | +------+
| QMeasure --+-+ | QMeasure --+-->|Q AF2 |
| QThreshold | | | QThreshold | +------+
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| Specific + | | | Specific + |
+----------+-+ | +----------+-+
| | +---+
+------+ | +------+ |
| +->|Q AF1 | |
| +------+ |
| |
| +----------------+ | +----------------+
+->|RandomDrop | +->|RandomDrop |
| MinThreshBytes | | MinThreshBytes |
| MinThreshPkts | | MinThreshPkts |
| MaxThreshBytes | | MaxThreshBytes |
| MaxThreshPkts | | MaxThreshPkts |
| ProbMax | | ProbMax |
| Weight | | Weight |
| SamplingRate | | SamplingRate |
+----------------+ +----------------+
Figure 8: Multiple Queue Random Dropper Usage Example
For this example, we have two queues, Q_AF1 and Q_AF2, sharing the
same buffer resources. We want to make sure the common buffer
resource is sufficient to service the AF11 traffic, and we want to
measure the two queues for determining the drop algorithm for AF11
traffic feeding into Q_AF1. Notice mQDrop is used for
dsAlgDropType of dsAlgDropEntry to indicate Multiple Queue Dropping
Algorithm.
The common shared buffer resource is indicated by the use of
dsAlgDropEntry, with their attributes used as follows:
- dsAlgDropType indicates the algorithm used, mQDrop.
- dsAlgDropNext is used to indicate the next functional data path
element to handle the flow when no drop occurs.
- dsAlgDropQMeasure is used as the anchor for the list of
dsMQAlgDropEntry, one for each queue being measured.
- dsAlgDropQThreshold is used to indicate the size of the shared
buffer pool.
- dsAlgDropSpecific can be used to reference instance of additional
PRC (not defined in this PIB) if more parameters are required to
describe the common shared buffer resource.
For this example, there are two subsequent dsMQAlgDropEntry, one for
each queue being measured, with its attributes used as follows:
- dsMQAlgDropType indicates the algorithm used, for this example,
both dsMQAlgDropType uses randomDrop.
- dsMQAlgDropQMeasure indicates the queue being measured.
- dsMQAlgDropNext indicates the next functional data path element
to handle the flow when no drop occurs.
- dsMQAlgDropExceedNext is used to indicate the next queue's
dsMQAlgDropEntry. With the use of zeroDotZero to indicate the
last queue.
- dsMQAlgDropQMeasure is used to indicate the queue being measured.
For this example, _Q AF1_ and _Q_AF2_ are the two queues used.
- dsAlgDropQThreshold is used as in single queue Random Dropper.
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- dsAlgDropSpecific is used to reference the PRID that describes
the dropper parameters as in its normal usage. For this example
both dsAlgDropSpecific reference dsRandomDropEntrys.
Notice the anchoring dsAlgDropEntry and the two dsMQAlgDropEntrys
all have their Next attribute pointing to Q_AF1. This indicates:
- If the packet does not need to be checked with the individual
queue's drop processing because of abundance of common shared
buffer resources, then the packet is sent to Q_AF1.
- If the packet is not dropped due to current Q_AF1 conditions, then
it is sent to Q_AF1.
- If the packet is not dropped due to current Q_AF2 conditions, then
it is sent to Q_AF1.
This example also uses two dsRandomDropEntry for the two queues it
measures. Their attribute usage is the same as if for single queue
random dropper.
Other more complex result combinations can be achieved by specifying
a new PRC and referencing this new PRC with dsAlgDropSpecific of the
anchoring dsAlgDropEntry. More simple usage can also be achieved
when a single set of drop parameters are used for all queues being
measured. This again can be referenced by the anchoring
dsAlgDropSpecific. These are not defined in this PIB.
5.6. Queue and Scheduler Example
The queue and scheduler example will continue from the dropper
example in previous section. Concentrating in the queue and
scheduler Diffserv datapath functional elements. Notice a shaper is
constructed using queue and scheduler with MaxRate parameters.
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+------------+ +-----------------+
---->|Q | +->|Scheduler |
| Id=EF | | | Id=Diffserv |
| Next ------+------------------------+ | Next=0.0 |
| MinRate ---+--+ | | Method=Priority |
| MaxRate -+ | | +----------+ | | MinRate=0.0 |
+----------+-+ +-->|MinRate | | | MaxRate=0.0 |
| | Priority | | +-----------------+
+----------+ | Absolute | |
| | Relative | |
| +-----------+ +----------+ |
+->|MaxRate | |
| Level | |
| Absolute | |
| Relative | |
| Threshold | |
+-----------+ +-------------+
|
+----------+ +------------+ |
---->|Q | +-->|Scheduler | |
| Id=AF1 | | | Id=AF | |
| Next ----+--------------------+ | Next ------+--+
| MinRate -+-+ | | Method=WRR |
| MaxRate | | +----------+ | | MinRate -+ |
+----------+ +->|MinRate | | | MaxRate | |
| Priority | | +----------+-+
| Absolute | | |
| Relative | | +----------+
+----------+ | |
+----------+ | | +------------+
---->|Q | | +->|MinRate |
| Id=AF2 | | | Priority |
| Next ----+--------------------+ | Absolute |
| MinRate -+-+ | | Relative |
| MaxRate | | +----------+ | +------------+
+----------+ +->|MinRate | |
| Priority | |
| Absolute | |
| Relative | |
+----------+ |
+----------+ |
---->|Q | |
| Id=AF3 | |
| Next ----+--------------------+
| MinRate -+-+
| MaxRate | | +----------+
+----------+ +->|MinRate |
| Priority |
| Absolute |
| Relative |
+----------+
Figure 9: Queue and Scheduler Usage Example
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This example shows the queuing system for handling EF, AF1, AF2, and
AF3 traffic. It is assumed AF11, AF12, and AF13 traffic feeds into
Queue AF1. And likewise for AF2x and AF3x traffic.
The AF1, AF2, and AF3 Queues are serviced by the AF Scheduler using
a Weighed Round Robin method. The AF Scheduler will service each of
the queues feeding into it based on the minimum rate parameters of
each queue.
The AF and EF traffic are serviced by the DiffServ Scheduler using a
Strict Priority method. The DiffServ Scheduler will service each of
its inputs based on their priority parameter.
Notice there is an upper bound to the servicing of EF traffic by the
DiffServ Scheduler. This is accomplished with the use of maximum
rate parameters. DiffServ Scheduler uses both the maximum rate and
priority parameters when servicing the EF Queue.
The DiffServ Scheduler is the last Diffserv datapath functional
element in this datapath. It uses zeroDotZero in its Next
attribute.
6. Summary of the DiffServ PIB
The DiffServ PIB consists of one module containing the base PRCs for
setting DiffServ policy, queues, classifiers, meters, etc., and
also contains capability PRC's that allow a PEP to specify its
device characteristics to the PDP. This module contains two groups,
which are summarized in this section.
Diffserv Capabilities Group
This group consists of PRCs to indicate to the PDP the types of
interface supported on the PEP in terms of their Diffserv
capabilities and PRCs that the PDP can install in order to
configure these interfaces (queues, scheduling parameters, buffer
sizes, etc.) to affect the desired policy. This group describes
capabilities in terms of the types of interfaces and takes
configuration in terms of interface types and role combinations
[FR-PIB]; it does not deal with individual interfaces on the
device.
Diffserv Policy Group
This group contains configuration of the functional elements that
comprise the Diffserv policy that applies to an interface and the
specific parameters that describe those elements. This group
contains classifiers, meters, actions, droppers, queues and
schedulers. This group also contains the PRC that associates the
datapath elements with role combinations.
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7. PIB Operational Overview
This section provides an operation overview of configuring DiffServ
QoS policy.
After initial PEP to PDP communication setup, using [COPS-PR] for
example, the PEP will provide to the PDP the PIB Provisioning
classes (PRCs), interface types, and interface type capabilities it
supports.
The PRCs supported by the PEP are reported to the PDP in the PRC
Support Table, frwkPrcSupportTable defined in the framework PIB [FR-
PIB]. Each instance of the frwkPrcSupportTable indicates a PRC that
the PEP understands and for which the PDP can send class instances
as part of the policy information.
The capabilities of interface types the PEP supports are described
by rows in the capability set table, frwkCapabilitySetTable. Each
row, or instance of this class contains a pointer to an instance of
a PRC that describes the capabilities of the interface type. The
capability objects may reside in the dsIfClassifierCapsTable, the
dsIfMeterCapsTable, the dsIfSchedulerCapsTable, the
dsIfElmDepthCapsTable, the dsIfElmOutputCapsTable, or in a table
defined in another PIB.
The PDP, with knowledge of the PEP's capabilities, then provides the
PEP with administrative domain and interface-type-specific policy
information.
Instances of the dsDataPathTable are used to specify the first
element in the set of functional elements applied to an interface
type. Each instance of the dsDataPathTable applies to an interface
type defined by its roles and direction (ingress or egress).
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8. PIB Definition
DIFFSERV-PIB PIB-DEFINITIONS ::= BEGIN
IMPORTS
Unsigned32, MODULE-IDENTITY, MODULE-COMPLIANCE,
OBJECT-TYPE, OBJECT-GROUP, pib
FROM COPS-PR-SPPI
InstanceId, Prid, TagId, TagReferenceId
FROM COPS-PR-SPPI-TC
zeroDotZero
FROM SNMPv2-SMI
AutonomousType
FROM SNMPv2-TC
SnmpAdminString
FROM SNMP-FRAMEWORK-MIB
RoleCombination, PrcIdentifierOid, PrcIdentifierOidOrZero,
AttrIdentifier
FROM FRAMEWORK-TC-PIB
Dscp
FROM DIFFSERV-DSCP-TC
IfDirection
FROM DIFFSERV-MIB
BurstSize
FROM INTEGRATED-SERVICES-MIB;
dsPolicyPib MODULE-IDENTITY
SUBJECT-CATEGORIES { tbd } -- DiffServ QoS COPS Client Type
-- to be assigned by IANA
LAST-UPDATED "200206122300Z"
ORGANIZATION "IETF DIFFSERV WG"
CONTACT-INFO "
Michael Fine
Atheros Communications
529 Almanor Ave
Sunnyvale, CA 94085 USA
Phone: +1 408 773 5324
Email: mfine@atheros.com
Keith McCloghrie
Cisco Systems, Inc.
170 West Tasman Drive,
San Jose, CA 95134-1706 USA
Phone: +1 408 526 5260
Email: kzm@cisco.com
John Seligson
Nortel Networks, Inc.
4401 Great America Parkway
Santa Clara, CA 95054 USA
Phone: +1 408 495 2992
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Email: jseligso@nortelnetworks.com
Kwok Ho Chan
Nortel Networks, Inc.
600 Technology Park Drive
Billerica, MA 01821 USA
Phone: +1 978 288 8175
Email: khchan@nortelnetworks.com
Differentiated Services Working Group:
diffserv@ietf.org"
DESCRIPTION
"The PIB module containing a set of provisioning classes
that describe quality of service (QoS) policies for
DiffServ. It includes general classes that may be extended
by other PIB specifications as well as a set of PIB
classes related to IP processing."
REVISION "200206122300Z"
DESCRIPTION
"Initial version, published as RFC xxxx."
::= { pib xxx } -- xxx to be assigned by IANA
dsCapabilityClasses OBJECT IDENTIFIER ::= { dsPolicyPib 1 }
dsPolicyClasses OBJECT IDENTIFIER ::= { dsPolicyPib 2 }
dsPolicyPibConformance OBJECT IDENTIFIER ::= { dsPolicyPib 3 }
--
-- Interface Type Capabilities Group
--
--
-- Interface Type Capability Tables
--
-- The Interface type capability tables define capabilities that may
-- be associated with interfaces of a specific type.
-- This PIB defines capability tables for Diffserv Functionalities.
--
--
-- The Base Capability Table
--
dsBaseIfCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsBaseIfCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"The Base Interface Type Capability class. This class
represents a generic capability supported by a device in the
ingress, egress, or both directions."
::= { dsCapabilityClasses 1 }
dsBaseIfCapsEntry OBJECT-TYPE
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SYNTAX DsBaseIfCapsEntry
STATUS current
DESCRIPTION
"An instance of this class describes the dsBaseIfCaps class."
PIB-INDEX { dsBaseIfCapsPrid }
::= { dsBaseIfCapsTable 1 }
DsBaseIfCapsEntry ::= SEQUENCE {
dsBaseIfCapsPrid InstanceId,
dsBaseIfCapsDirection INTEGER
}
dsBaseIfCapsPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsBaseIfCapsEntry 1 }
dsBaseIfCapsDirection OBJECT-TYPE
SYNTAX INTEGER {
inbound(1),
outbound(2),
inAndOut(3)
}
STATUS current
DESCRIPTION
"This object specifies the direction(s) for which the
capability applies. A value of 'inbound(1)' means the
capability applies only to the ingress direction. A value of
'outbound(2)' means the capability applies only to the egress
direction. A value of 'inAndOut(3)' means the capability
applies to both directions."
::= { dsBaseIfCapsEntry 2 }
--
-- The Classification Capability Table
--
dsIfClassificationCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfClassificationCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies the classification capabilities of
a Capability Set."
::= { dsCapabilityClasses 2 }
dsIfClassificationCapsEntry OBJECT-TYPE
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SYNTAX DsIfClassificationCapsEntry
STATUS current
DESCRIPTION
"An instance of this class describes the classification
capabilities of a Capability Set."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfClassificationCapsSpec }
::= { dsIfClassificationCapsTable 1 }
DsIfClassificationCapsEntry ::= SEQUENCE {
dsIfClassificationCapsSpec BITS
}
dsIfClassificationCapsSpec OBJECT-TYPE
SYNTAX BITS {
ipSrcAddrClassification(0),
-- indicates the ability to classify based on
-- IP source addresses
ipDstAddrClassification(1),
-- indicates the ability to classify based on
-- IP destination addresses
ipProtoClassification(2),
-- indicates the ability to classify based on
-- IP protocol numbers
ipDscpClassification(3),
-- indicates the ability to classify based on
-- IP DSCP
ipL4Classification(4),
-- indicates the ability to classify based on
-- IP layer 4 port numbers for UDP and TCP
ipV6FlowID(5)
-- indicates the ability to classify based on
-- IPv6 FlowIDs.
}
STATUS current
DESCRIPTION
"Bit set of supported classification capabilities. In
addition to these capabilities, other PIBs may define other
capabilities that can then be specified in addition to the
ones specified here (or instead of the ones specified here if
none of these are specified)."
::= { dsIfClassificationCapsEntry 1 }
--
-- Metering Capabilities
--
dsIfMeteringCapsTable OBJECT-TYPE
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SYNTAX SEQUENCE OF DsIfMeteringCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies the metering capabilities of a
Capability Set."
::= { dsCapabilityClasses 3 }
dsIfMeteringCapsEntry OBJECT-TYPE
SYNTAX DsIfMeteringCapsEntry
STATUS current
DESCRIPTION
"An instance of this class describes the metering
capabilities of a Capability Set."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfMeteringCapsSpec }
::= { dsIfMeteringCapsTable 1 }
DsIfMeteringCapsEntry ::= SEQUENCE {
dsIfMeteringCapsSpec BITS
}
dsIfMeteringCapsSpec OBJECT-TYPE
SYNTAX BITS {
zeroNotUsed(0),
simpleTokenBucket(1),
avgRate(2),
srTCMBlind(3),
srTCMAware(4),
trTCMBlind(5),
trTCMAware(6),
tswTCM(7)
}
STATUS current
DESCRIPTION
"Bit set of supported metering capabilities. As with
classification capabilities, these metering capabilities may
be augmented by capabilities specified in other PRCs (in other
PIBs)."
::= { dsIfMeteringCapsEntry 1 }
--
-- Algorithmic Dropper Capabilities
--
dsIfAlgDropCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfAlgDropCapsEntry
PIB-ACCESS notify
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STATUS current
DESCRIPTION
"This class specifies the algorithmic dropper
capabilities of a Capability Set.
This capability table indicates the types of algorithmic
drop supported by a Capability Set for a specific flow
direction.
Additional capabilities affecting the drop functionalities
are determined based on queue capabilities associated with
specific instance of a dropper, hence not specified by
this class."
::= { dsCapabilityClasses 4 }
dsIfAlgDropCapsEntry OBJECT-TYPE
SYNTAX DsIfAlgDropCapsEntry
STATUS current
DESCRIPTION
"An instance of this class describes the algorithmic dropper
capabilities of a Capability Set."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfAlgDropCapsType,
dsIfAlgDropCapsMQCount }
::= { dsIfAlgDropCapsTable 1 }
DsIfAlgDropCapsEntry ::= SEQUENCE {
dsIfAlgDropCapsType BITS,
dsIfAlgDropCapsMQCount Unsigned32
}
dsIfAlgDropCapsType OBJECT-TYPE
SYNTAX BITS {
zeroNotUsed(0),
oneNotUsed(1),
tailDrop(2),
headDrop(3),
randomDrop(4),
alwaysDrop(5),
mQDrop(6) }
STATUS current
DESCRIPTION
"The type of algorithm that droppers associated with queues
may use.
The tailDrop(2) algorithm means that packets are dropped from
the tail of the queue when the associated queue's MaxQueueSize
is exceeded. The headDrop(3) algorithm means that packets are
dropped from the head of the queue when the associated queue's
MaxQueueSize is exceeded. The randomDrop(4) algorithm means
that an algorithm is executed which may randomly
drop the packet, or drop other packet(s) from the queue
in its place. The specifics of the algorithm may be
proprietary. However, parameters would be specified in the
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dsRandomDropTable. The alwaysDrop(5) will drop every packet
presented to it. The mQDrop(6) algorithm will drop packets
based on measurement from multiple queues."
::= { dsIfAlgDropCapsEntry 1 }
dsIfAlgDropCapsMQCount OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
STATUS current
DESCRIPTION
"Indicates the number of queues measured for the drop
algorithm.
This attribute is ignored when alwaysDrop(5) algorithm is
used. This attribute contains the value of 1 for all drop
algorithm types except for mQDrop(6), where this attribute
is used to indicate the maximum number of dsMQAlgDropEntry
that can be chained together."
::= { dsIfAlgDropCapsEntry 2 }
--
-- Queue Capabilities
--
dsIfQueueCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfQueueCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies the queueing capabilities of a
Capability Set."
::= { dsCapabilityClasses 5 }
dsIfQueueCapsEntry OBJECT-TYPE
SYNTAX DsIfQueueCapsEntry
STATUS current
DESCRIPTION
"An instance of this class describes the queue
capabilities of a Capability Set."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfQueueCapsMinQueueSize,
dsIfQueueCapsMaxQueueSize,
dsIfQueueCapsTotalQueueSize }
::= { dsIfQueueCapsTable 1 }
DsIfQueueCapsEntry ::= SEQUENCE {
dsIfQueueCapsMinQueueSize Unsigned32,
dsIfQueueCapsMaxQueueSize Unsigned32,
dsIfQueueCapsTotalQueueSize Unsigned32
}
dsIfQueueCapsMinQueueSize OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
UNITS "Bytes"
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STATUS current
DESCRIPTION
"Some interfaces may allow the size of a queue to be
configured. This attribute specifies the minimum size that
can be configured for a queue, specified in bytes.
dsIfQueueCapsMinQueueSize must be less than or equals to
dsIfQueueCapsMaxQueueSize when both are specified.
A zero value indicates not specified."
::= { dsIfQueueCapsEntry 1 }
dsIfQueueCapsMaxQueueSize OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
UNITS "Bytes"
STATUS current
DESCRIPTION
"Some interfaces may allow the size of a queue to be
configured. This attribute specifies the maximum size that
can be configured for a queue, specified in bytes.
dsIfQueueCapsMinQueueSize must be less than or equals to
dsIfQueueCapsMaxQueueSize when both are specified.
A zero value indicates not specified."
::= { dsIfQueueCapsEntry 2 }
dsIfQueueCapsTotalQueueSize OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
UNITS "Bytes"
STATUS current
DESCRIPTION
"Some interfaces may have a limited buffer space to be
shared amongst all queues of that interface while also
allowing the size of each queue to be configurable. To
prevent the situation where the PDP configures the sizes of
the queues in excess of the total buffer available to the
interface, the PEP can report the total buffer space in
bytes available with this capability.
A zero value indicates not specified."
::= { dsIfQueueCapsEntry 3 }
--
-- Scheduler Capabilities
--
dsIfSchedulerCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfSchedulerCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies the scheduler capabilities of a
Capability Set."
::= { dsCapabilityClasses 6 }
dsIfSchedulerCapsEntry OBJECT-TYPE
SYNTAX DsIfSchedulerCapsEntry
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STATUS current
DESCRIPTION
"An instance of this class describes the scheduler
capabilities of a Capability Set."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfSchedulerCapsServiceDisc,
dsIfSchedulerCapsMaxInputs }
::= { dsIfSchedulerCapsTable 1 }
DsIfSchedulerCapsEntry ::= SEQUENCE {
dsIfSchedulerCapsServiceDisc AutonomousType,
dsIfSchedulerCapsMaxInputs Unsigned32,
dsIfSchedulerCapsMinMaxRate INTEGER
}
dsIfSchedulerCapsServiceDisc OBJECT-TYPE
SYNTAX AutonomousType
STATUS current
DESCRIPTION
"The scheduling discipline for which the set of capabilities
specified in this object apply. Object identifiers for several
general purpose and well-known scheduling disciplines are
shared with and defined in the Diffserv MIB.
These include diffServSchedulerPriority,
diffServSchedulerWRR, diffServSchedulerWFQ."
::= { dsIfSchedulerCapsEntry 1 }
dsIfSchedulerCapsMaxInputs OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
STATUS current
DESCRIPTION
"The maximum number of queues and/or schedulers that can
feed into a scheduler indicated by this capability entry.
A value of zero means there is no maximum."
::= { dsIfSchedulerCapsEntry 2 }
dsIfSchedulerCapsMinMaxRate OBJECT-TYPE
SYNTAX INTEGER {
minRate(1),
maxRate(2),
minAndMaxRates(3)
}
STATUS current
DESCRIPTION
"Scheduler capability indicating ability to handle inputs
with minimum rate, maximum rate, or both."
::= { dsIfSchedulerCapsEntry 3 }
--
-- Maximum Rate Capabilities
--
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dsIfMaxRateCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfMaxRateCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies the maximum rate capabilities of a
Capability Set."
::= { dsCapabilityClasses 7 }
dsIfMaxRateCapsEntry OBJECT-TYPE
SYNTAX DsIfMaxRateCapsEntry
STATUS current
DESCRIPTION
"An instance of this class describes the maximum rate
capabilities of a Capability Set."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfMaxRateCapsMaxLevels }
::= { dsIfMaxRateCapsTable 1 }
DsIfMaxRateCapsEntry ::= SEQUENCE {
dsIfMaxRateCapsMaxLevels Unsigned32
}
dsIfMaxRateCapsMaxLevels OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
STATUS current
DESCRIPTION
"The maximum number of levels a maximum rate specification
may have for this Capability Set and flow direction."
::= { dsIfMaxRateCapsEntry 1 }
--
-- Datapath Element Linkage Capabilities
--
--
-- Datapath Element Cascade Depth
--
dsIfElmDepthCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfElmDepthCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies the number of elements of the same
type that can be cascaded together in a data path."
::= { dsCapabilityClasses 8 }
dsIfElmDepthCapsEntry OBJECT-TYPE
SYNTAX DsIfElmDepthCapsEntry
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STATUS current
DESCRIPTION
"An instance of this class describes the cascade depth
for a particular functional datapath element PRC. A
functional datapath element not represented in this
class can be assumed to have no specific maximum
depth."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfElmDepthCapsPrc }
::= { dsIfElmDepthCapsTable 1 }
DsIfElmDepthCapsEntry ::= SEQUENCE {
dsIfElmDepthCapsPrc PrcIdentifierOid,
dsIfElmDepthCapsCascadeMax Unsigned32
}
dsIfElmDepthCapsPrc OBJECT-TYPE
SYNTAX PrcIdentifierOid
STATUS current
DESCRIPTION
"The object identifier of a PRC that represents a functional
datapath element. This may be one of: dsClfrElementEntry,
dsMeterEntry, dsActionEntry, dsAlgDropEntry, dsQEntry, or
dsSchedulerEntry.
There may not be more than one instance of this class with
the same value of dsIfElmDepthCapsPrc and same value of
dsBaseIfCapsDirection. Must not contain the value of
zeroDotZero."
::= { dsIfElmDepthCapsEntry 1 }
dsIfElmDepthCapsCascadeMax OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
STATUS current
DESCRIPTION
"The maximum number of elements of type dsIfElmDepthCapsPrc
that can be linked consecutively in a data path. A value of
zero indicates there is no specific maximum."
::= { dsIfElmDepthCapsEntry 2 }
--
-- Datapath Element Linkage Types
--
dsIfElmLinkCapsTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsIfElmLinkCapsEntry
PIB-ACCESS notify
STATUS current
DESCRIPTION
"This class specifies what types of datapath functional
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elements may be used as the next downstream element for
a specific type of functional element."
::= { dsCapabilityClasses 9 }
dsIfElmLinkCapsEntry OBJECT-TYPE
SYNTAX DsIfElmLinkCapsEntry
STATUS current
DESCRIPTION
"An instance of this class specifies a PRC that may
be used as the next functional element after a specific
type of element in a data path."
EXTENDS { dsBaseIfCapsEntry }
UNIQUENESS { dsBaseIfCapsDirection,
dsIfElmLinkCapsPrc,
dsIfElmLinkCapsAttr,
dsIfElmLinkCapsNextPrc }
::= { dsIfElmLinkCapsTable 1 }
DsIfElmLinkCapsEntry ::= SEQUENCE {
dsIfElmLinkCapsPrc PrcIdentifierOid,
dsIfElmLinkCapsAttr AttrIdentifier,
dsIfElmLinkCapsNextPrc PrcIdentifierOidOrZero
}
dsIfElmLinkCapsPrc OBJECT-TYPE
SYNTAX PrcIdentifierOid
STATUS current
DESCRIPTION
" The object identifier of a PRC that represents a functional
datapath element. This may be one of: dsClfrElementEntry,
dsMeterEntry, dsActionEntry, dsAlgDropEntry, dsQEntry, or
dsSchedulerEntry.
This must not have the value zeroDotZero."
::= { dsIfElmLinkCapsEntry 1 }
dsIfElmLinkCapsAttr OBJECT-TYPE
SYNTAX AttrIdentifier
STATUS current
DESCRIPTION
"The value represents the attribute in the PRC
indicated by dsIfElmLinkCapsPrc that is used to
specify the next functional element in the datapath."
::= { dsIfElmLinkCapsEntry 2 }
dsIfElmLinkCapsNextPrc OBJECT-TYPE
SYNTAX PrcIdentifierOidOrZero
STATUS current
DESCRIPTION
"The value is the OID of a PRC table entry from which
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instances can be referenced by the attribute indicated
by dsIfElmLinkCapsPrc and dsIfElmLinkAttr.
For example, suppose a meter's success output can be an
action or another meter, and the fail output can only be
an action. This can be expressed as follows:
Prid Prc Attr NextPrc
1 dsMeterEntry dsMeterSucceedNext dsActionEntry
2 dsMeterEntry dsMeterSucceedNext dsMeterEntry
3 dsMeterEntry dsMeterFailNext dsActionEntry.
zeroDotZero is a valid value for this attribute to
specify that the PRC specified in dsIfElmLinkCapsPrc
is the last functional data path element."
::= { dsIfElmLinkCapsEntry 3 }
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--
-- Policy Classes
--
--
-- Data Path Table
--
dsDataPathTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsDataPathEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The data path table indicates the start of
functional data paths in this device.
The Data Path Table enumerates the Differentiated
Services Functional Data Paths within this device.
Each entry specifies the first functional datapath
element to process data flow for each specific datapath.
Each datapath is defined by the interface set's capability
set name, role combination, and direction. This class can
therefore have up to two entries for each interface set,
ingress and egress."
::= { dsPolicyClasses 1 }
dsDataPathEntry OBJECT-TYPE
SYNTAX DsDataPathEntry
STATUS current
DESCRIPTION
"Each entry in this class indicates the start of a single
functional data path, defined by its capability set name,
role combination and traffic direction. The first
functional datapath element to handle traffic for each
data path is defined by the dsDataPathStart attribute
of each table entry.
Notice for each entry:
1. dsDataPathCapSetName must reference an existing capability
set name in frwkCapabilitySetTable [FR-PIB].
2. dsDataPathRoles must reference existing Role Combination
in frwkIfRoleComboTable [FR-PIB].
3. dsDataPathStart must reference an existing entry in a
functional data path element table.
If any one or more of these three requirements is not
satisfied, the dsDataPathEntry will not be installed."
PIB-INDEX { dsDataPathPrid }
UNIQUENESS { dsDataPathCapSetName,
dsDataPathRoles,
dsDataPathIfDirection }
::= { dsDataPathTable 1 }
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DsDataPathEntry ::= SEQUENCE {
dsDataPathPrid InstanceId,
dsDataPathCapSetName SnmpAdminString,
dsDataPathRoles RoleCombination,
dsDataPathIfDirection IfDirection,
dsDataPathStart Prid
}
dsDataPathPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsDataPathEntry 1 }
dsDataPathCapSetName OBJECT-TYPE
SYNTAX SnmpAdminString
STATUS current
DESCRIPTION
"The capability set associated with this data path entry.
The capability set name specified by this attribute
must exist in the frwkCapabilitySetTable [FR-PIB]
prior to association with an instance of this class."
::= { dsDataPathEntry 2 }
dsDataPathRoles OBJECT-TYPE
SYNTAX RoleCombination
STATUS current
DESCRIPTION
"The interfaces to which this data path entry applies,
specified in terms of roles. There must exist an entry
in the frwkIfRoleComboTable [FR-PIB] specifying
this role combination, together with the capability
set specified by dsDataPathCapSetName, prior to
association with an instance of this class."
::= { dsDataPathEntry 3 }
dsDataPathIfDirection OBJECT-TYPE
SYNTAX IfDirection
STATUS current
DESCRIPTION
"Specifies the direction for which this data path
entry applies."
::= { dsDataPathEntry 4 }
dsDataPathStart OBJECT-TYPE
SYNTAX Prid
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STATUS current
DESCRIPTION
"This selects the first functional datapath element
to handle traffic for this data path. This
Prid should point to an instance of one of:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
dsQEntry
The PRI pointed to must exist prior to the installation of
this datapath start element."
::= { dsDataPathEntry 5 }
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--
-- Classifiers
--
-- Classifier 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 all traffic handled by a classifier must match
-- at least one classifier element within the classifier,
-- with the classifier element parameters specified by a filter.
-- It is the PDP's responsibility to create a _catch all_ classifier
-- element and filter that matches all packet. This _catch all_
-- classifier element should have the lowest Precedence value.
--
-- 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.
--
-- Each entry in the classifier table represents a classifier, with
-- classifier element table handling the fan-out functionality of a
-- classifier, and filter table defining the classification
-- patterns.
--
--
-- Classifier Table
--
dsClfrTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsClfrEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"This table enumerates all the Diffserv classifier functional
data path elements of this device. The actual classification
definitions are detailed in dsClfrElementTable entries
belonging to each classifier. Each classifier is referenced
by its classifier elements using its classifier ID.
An entry in this table, referenced by an upstream functional
data path element or a datapath table entry, is the entry
point to the classifier functional data path element.
The dsClfrId of each entry is used to organize all
classifier elements belonging to the same classifier."
REFERENCE
"[MODEL] section 4.1"
::= { dsPolicyClasses 2 }
dsClfrEntry OBJECT-TYPE
SYNTAX DsClfrEntry
STATUS current
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DESCRIPTION
"An entry in the classifier table describes a single
classifier. Each classifier element belonging to this
classifier must have its dsClfrElementClfrId attribute equal
to dsClfrId."
PIB-INDEX { dsClfrPrid }
UNIQUENESS { dsClfrId }
::= { dsClfrTable 1 }
DsClfrEntry ::= SEQUENCE {
dsClfrPrid InstanceId,
dsClfrId TagReferenceId
}
dsClfrPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsClfrEntry 1 }
dsClfrId OBJECT-TYPE
SYNTAX TagReferenceId
PIB-TAG { dsClfrElementClfrId }
STATUS current
DESCRIPTION
"Identifies a Classifier. A Classifier must be
complete, this means all traffic handled by a
Classifier must match at least one Classifier
Element within the Classifier."
::= { dsClfrEntry 2 }
--
-- Classifier Element Table
--
dsClfrElementTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsClfrElementEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"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
diffserv functional datapath element when the
classification pattern is satisfied. Hence
the classifier element table enumerates the relationship
between classification patterns and subsequent downstream
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diffserv functional data path elements, describing one
branch of the fan-out characteristic of a classifier
indicated in [Model].
Classification parameters are defined by entries of filter
tables pointed to by dsClfrElementSpecific. There can be
filter tables of different types, and they can be inter-mixed
and used within a classifier. An example of a filter table is
the frwkIpFilterTable [FR-PIB], for IP Multi-Field
Classifiers (MFCs).
If there is ambiguity between classifier elements of the same
classifier, then dsClfrElementPrecedence needs to be used."
::= { dsPolicyClasses 3 }
dsClfrElementEntry OBJECT-TYPE
SYNTAX DsClfrElementEntry
STATUS current
DESCRIPTION
"An entry in the classifier element table describes a
single element of the classifier."
PIB-INDEX { dsClfrElementPrid }
UNIQUENESS { dsClfrElementClfrId,
dsClfrElementPrecedence,
dsClfrElementSpecific }
::= { dsClfrElementTable 1 }
DsClfrElementEntry ::= SEQUENCE {
dsClfrElementPrid InstanceId,
dsClfrElementClfrId TagId,
dsClfrElementPrecedence Unsigned32,
dsClfrElementNext Prid,
dsClfrElementSpecific Prid
}
dsClfrElementPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsClfrElementEntry 1 }
dsClfrElementClfrId OBJECT-TYPE
SYNTAX TagId
STATUS current
DESCRIPTION
"A classifier is composed of one or more classifier
elements. Each classifier element belonging to
the same classifier uses the same classifier ID.
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Hence, A classifier Id identifies which classifier
this classifier element is a part of. This must be
the value of dsClfrId attribute for an existing
instance of dsClfrEntry."
::= { dsClfrElementEntry 2 }
dsClfrElementPrecedence OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
STATUS current
DESCRIPTION
"The relative order in which classifier elements are
applied: higher numbers represent classifier elements
with higher precedence. Classifier elements with the
same precedence 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 precedence may
overlap in their filters: the classifier element with
the highest precedence 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 that there will always be one
or more filters that match every possible pattern
that could be presented in an incoming packet.
There is no such requirement in the egress direction."
::= { dsClfrElementEntry 3 }
dsClfrElementNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This attribute provides one branch of the fan-out
functionality of a classifier described in Diffserv
Model section 4.1.
This selects the next diffserv functional datapath
element to handle traffic for this data path.
A value of zeroDotZero marks the end of DiffServ processing
for this data path. Any other value must point to a
valid (pre-existing) instance of one of:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
dsQEntry."
DEFVAL { zeroDotZero }
::= { dsClfrElementEntry 4 }
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dsClfrElementSpecific OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"A pointer to a valid entry in another table that
describes the applicable classification filter, e.g.
an entry in frwkIpFilterTable (Framework PIB).
The PRI pointed to must exist prior to the installation of
this classifier element.
The value zeroDotZero is interpreted to match any-
thing not matched by another classifier element - only one
such entry may exist for each classifier."
::= { dsClfrElementEntry 5 }
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--
-- Meters
--
-- This PIB supports a variety of Meters. It includes a
-- specific definition for Meters whose parameter set can
-- be modelled using Token Bucket parameters.
-- Other metering parameter sets can be defined by other PIBs.
--
-- Multiple meter elements may be logically cascaded
-- using their dsMeterSucceedNext and dsMeterFailNext 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 PIB 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 PIB.
--
-- srTCM meters (RFC 2697) can be specified using two sets of
-- dsMeterEntry and dsTBParamEntry. First set specifies the
-- Committed Information Rate and Committed Burst Size
-- token-bucket. Second set specifies the Excess Burst
-- Size token-bucket.
--
-- trTCM meters (RFC 2698) can be specified using two sets of
-- dsMeterEntry and dsTBParamEntry. First set specifies the
-- Committed Information Rate and Committed Burst Size
-- token-bucket. Second set specifies the Peak Information
-- Rate and Peak Burst Size token-bucket.
--
-- tswTCM meters (RFC 2859) can be specified using two sets of
-- dsMeterEntry and dsTBParamEntry. First set specifies the
-- Committed Target Rate token-bucket. Second set specifies the
-- Peak Target Rate token-bucket. dsTBParamInterval in each
-- token bucket reflects the Average Interval.
--
dsMeterTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsMeterEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"This class enumerates specific meters that a system
may use to police a stream of traffic. The traffic
stream to be metered is determined by the element(s)
upstream of the meter i.e. by the object(s) that
point to each entry in this class. This may include
all traffic on an interface.
Specific meter details are to be found in table entry
referenced by dsMeterSpecific."
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REFERENCE "[MODEL] section 5"
::= { dsPolicyClasses 4 }
dsMeterEntry OBJECT-TYPE
SYNTAX DsMeterEntry
STATUS current
DESCRIPTION
"An entry in the meter table describes a single
conformance level of a meter."
PIB-INDEX { dsMeterPrid }
UNIQUENESS { dsMeterSucceedNext,
dsMeterFailNext,
dsMeterSpecific }
::= { dsMeterTable 1 }
DsMeterEntry ::= SEQUENCE {
dsMeterPrid InstanceId,
dsMeterSucceedNext Prid,
dsMeterFailNext Prid,
dsMeterSpecific Prid
}
dsMeterPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsMeterEntry 1 }
dsMeterSucceedNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"If the traffic does conform, this selects the next
diffserv functional datapath element to handle
traffic for this data path.
The value zeroDotZero in this variable indicates no
further Diffserv treatment is performed on traffic of
this datapath. Any other value must point to a valid
(pre-existing) instance of one of:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
dsQEntry."
DEFVAL { zeroDotZero }
::= { dsMeterEntry 2 }
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dsMeterFailNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"If the traffic does not conform, this selects the
next diffserv functional datapath element to handle
traffic for this data path.
The value zeroDotZero in this variable indicates no
further Diffserv treatment is performed on traffic of
this datapath. Any other value must point to a valid
(pre-existing) instance of one of:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
dsQEntry."
DEFVAL { zeroDotZero }
::= { dsMeterEntry 3 }
dsMeterSpecific OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This indicates the behaviour of the meter by point-
ing to an entry containing detailed parameters. Note
that entries in that specific table must be managed
explicitly.
For example, dsMeterSpecific may point to an
entry in dsTBMeterTable, which contains an
instance of a single set of Token Bucket parameters.
The PRI pointed to must exist prior to installing this
Meter datapath element."
::= { dsMeterEntry 4 }
--
-- Token-Bucket Parameter Table
--
-- Each entry in the Token Bucket Parameter Table parameterizes
-- 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, pointed to, by multiple dsMeterTable entries.
--
dsTBParamTable OBJECT-TYPE
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DiffServ QoS Policy Information Base June 2002
SYNTAX SEQUENCE OF DsTBParamEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"This table enumerates token-bucket meter parameter sets
that a system may use to police a stream of traffic.
Such parameter sets are modelled here as each having a single
rate and a single burst size. Multiple entries are used
when multiple rates/burst sizes are needed."
REFERENCE
"[MODEL] section 5.1"
::= { dsPolicyClasses 5 }
dsTBParamEntry OBJECT-TYPE
SYNTAX DsTBParamEntry
STATUS current
DESCRIPTION
"An entry that describes a single token-bucket
parameter set."
PIB-INDEX { dsTBParamPrid }
UNIQUENESS { dsTBParamType,
dsTBParamRate,
dsTBParamBurstSize,
dsTBParamInterval }
::= { dsTBParamTable 1 }
DsTBParamEntry ::= SEQUENCE {
dsTBParamPrid InstanceId,
dsTBParamType AutonomousType,
dsTBParamRate Unsigned32,
dsTBParamBurstSize BurstSize,
dsTBParamInterval Unsigned32
}
dsTBParamPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsTBParamEntry 1 }
dsTBParamType OBJECT-TYPE
SYNTAX AutonomousType
STATUS current
DESCRIPTION
"The Metering algorithm associated with the
Token-Bucket parameters. zeroDotZero indicates this
is unknown.
Standard values for generic algorithms are as follows:
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diffServTBParamSimpleTokenBucket, diffServTBParamAvgRate,
diffServTBParamSrTCMBlind, diffServTBParamSrTCMAware,
diffServTBParamTrTCMBlind, diffServTBParamTrTCMAware,
diffServTBParamTswTCM
These are specified in the Diffserv MIB."
REFERENCE
"[MODEL] section 5.1"
::= { dsTBParamEntry 2 }
dsTBParamRate OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "kilobits per second"
STATUS current
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 [MODEL] section 5.1.1"
::= { dsTBParamEntry 3 }
dsTBParamBurstSize OBJECT-TYPE
SYNTAX BurstSize
UNITS "Bytes"
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 [MODEL] section 5."
::= { dsTBParamEntry 4 }
dsTBParamInterval OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "microseconds"
STATUS current
DESCRIPTION
"The time interval used with the token bucket. For:
1. Average Rate Meter, [MODEL] section 5.1.1,
-Delta.
2. Simple Token Bucket Meter, [MODEL] section
5.1.3, - time interval t.
3. RFC 2859 TSWTCM, - AVG_INTERVAL.
4. RFC 2697 srTCM, RFC 2698 trTCM, -
token bucket update time interval."
::= { dsTBParamEntry 5 }
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--
-- Actions
--
--
-- The Action Table allows enumeration of the different
-- types of actions to be applied to a traffic flow.
--
dsActionTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsActionEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The Action Table enumerates actions that can be per-
formed to a stream of traffic. Multiple actions can
be concatenated.
Specific actions are indicated by dsAction-
Specific which points to an entry of a specific
action type parameterizing the action in detail."
REFERENCE
"[MODEL] section 6."
::= { dsPolicyClasses 6 }
dsActionEntry OBJECT-TYPE
SYNTAX DsActionEntry
STATUS current
DESCRIPTION
"Each entry in the action table allows description of
one specific action to be applied to traffic."
PIB-INDEX { dsActionPrid }
UNIQUENESS { dsActionNext,
dsActionSpecific }
::= { dsActionTable 1 }
DsActionEntry ::= SEQUENCE {
dsActionPrid InstanceId,
dsActionNext Prid,
dsActionSpecific Prid
}
dsActionPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
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::= { dsActionEntry 1 }
dsActionNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This selects the next diffserv functional datapath
element to handle traffic for this data path.
The value zeroDotZero in this variable indicates no
further Diffserv treatment is performed on traffic of
this datapath. Any other value must point to a valid
(pre-existing) instance of one of:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
dsQEntry."
DEFVAL { zeroDotZero }
::= { dsActionEntry 2 }
dsActionSpecific OBJECT-TYPE
SYNTAX Prid
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 PIB module,
this should point to an instance of dsDscpMarkActEntry.
For other actions, it may point to an instance of a
PRC defined in some other PIB.
The PRI pointed to must exist prior to installing this
action datapath entry."
::= { dsActionEntry 3 }
-- DSCP Mark Action Table
--
-- Rows of this class are pointed to by dsActionSpecific
-- to provide detailed parameters specific to the DSCP
-- Mark action.
-- This class should at most contain one entry for each supported
-- DSCP value. These entries should be reused by different
-- dsActionEntry in same or different data paths.
--
dsDscpMarkActTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsDscpMarkActEntry
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PIB-ACCESS install
STATUS current
DESCRIPTION
"This class enumerates specific DSCPs used for marking or
remarking the DSCP field of IP packets. The entries of this
table may be referenced by a dsActionSpecific attribute."
REFERENCE
"[MODEL] section 6.1"
::= { dsPolicyClasses 7 }
dsDscpMarkActEntry OBJECT-TYPE
SYNTAX DsDscpMarkActEntry
STATUS current
DESCRIPTION
"An entry in the DSCP mark action table that describes a
single DSCP used for marking."
PIB-INDEX { dsDscpMarkActPrid }
UNIQUENESS { dsDscpMarkActDscp }
::= { dsDscpMarkActTable 1 }
DsDscpMarkActEntry ::= SEQUENCE {
dsDscpMarkActPrid InstanceId,
dsDscpMarkActDscp Dscp
}
dsDscpMarkActPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsDscpMarkActEntry 1 }
dsDscpMarkActDscp OBJECT-TYPE
SYNTAX Dscp
STATUS current
DESCRIPTION
"The DSCP that this Action uses for marking/remarking
traffic. Note that a DSCP value of -1 is not permit-
ted in this class. It is quite possible that the
only packets subject to this Action are already
marked with this DSCP. Note also that Diffserv may
result in packet remarking both on ingress to a net-
work and on egress from it and it is quite possible
that ingress and egress would occur in the same
router."
::= { dsDscpMarkActEntry 2 }
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--
-- Algorithmic Drop Table
--
-- Algorithmic Drop Table is the entry point for the Algorithmic
-- Dropper functional data path element.
-- For a simple algorithmic dropper, a single algorithmic drop entry
-- will be sufficient to parameterize the dropper.
-- For more complex algorithmic dropper, the dsAlgDropSpecific
-- attribute can be used to reference an entry in a parameter table,
-- e.g. dsRandomDropTable for random dropper.
-- For yet more complex dropper, for example, dropper that measures
-- multiple queues, each queue with its own algorithm, can use a
-- dsAlgDropTable entry as the entry point for Algorithmic Dropper
-- functional data path element, leaving the dropper parameters
-- for each queue be specified by entries of dsMQAlgDropTable.
-- In such usage, the anchoring dsAlgDropEntry's dsAlgDropType
-- should be mQDrop, and its dsAlgDropQMeasure should reference
-- the subsequent dsMQAlgDropEntry's, its dsAlgDropSpecific
-- should be used to reference parameters applicable to all the
-- queues being measured.
-- The subsequent dsMQAlgDropEntry's will provide the parameters,
-- one for each queue being measured. The dsMQAlgDropEntry's are
-- chained using their dsMQAlgDropNext attributes.
--
dsAlgDropTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsAlgDropEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The algorithmic drop table contains entries describ-
ing a functional data path element that drops
packets according to some algorithm."
REFERENCE
"[MODEL] section 7.1.3"
::= { dsPolicyClasses 8 }
dsAlgDropEntry OBJECT-TYPE
SYNTAX DsAlgDropEntry
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 dsAlgDropType
and with more detail parameter entry pointed to by
dsAlgDropSpecific when necessary."
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PIB-INDEX { dsAlgDropPrid }
UNIQUENESS { dsAlgDropType,
dsAlgDropNext,
dsAlgDropQMeasure,
dsAlgDropQThreshold,
dsAlgDropSpecific }
::= { dsAlgDropTable 1 }
DsAlgDropEntry ::= SEQUENCE {
dsAlgDropPrid InstanceId,
dsAlgDropType INTEGER,
dsAlgDropNext Prid,
dsAlgDropQMeasure Prid,
dsAlgDropQThreshold Unsigned32,
dsAlgDropSpecific Prid
}
dsAlgDropPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsAlgDropEntry 1 }
dsAlgDropType OBJECT-TYPE
SYNTAX INTEGER {
other(1),
tailDrop(2),
headDrop(3),
randomDrop(4),
alwaysDrop(5),
mQDrop(6)
}
STATUS current
DESCRIPTION
"The type of algorithm used by this dropper. A value
of tailDrop(2), headDrop(3), or alwaysDrop(5) represents
an algorithm that is completely specified by this PIB.
A value of other(1) indicates that the specifics of
the drop algorithm are specified in some other PIB
module, and that the dsAlgDropSpecific attribute
points to an instance of a PRC in that PIB that
specifies the information necessary to implement the
algorithm.
The tailDrop(2) algorithm is described as follows:
dsAlgDropQThreshold represents the depth of the
queue, pointed to by dsAlgDropQMeasure, at
which all newly arriving packets will be dropped.
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The headDrop(3) algorithm is described as follows: if
a packet arrives when the current depth of the queue,
pointed to by dsAlgDropQMeasure, is at
dsAlgDropQThreshold, 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.
The randomDrop(4) algorithm is described as follows:
on packet arrival, an algorithm is executed which may
randomly drop the packet, or drop other packet(s)
from the queue in its place. The specifics of the
algorithm may be proprietary. For this algorithm,
dsAlgDropSpecific points to a dsRandomDropEntry
that describes the algorithm. For this
algorithm, dsAlgQThreshold is understood to be
the absolute maximum size of the queue and additional
parameters are described in dsRandomDropTable.
The alwaysDrop(5) algorithm always drops packets. In
this case, the other configuration values in this Entry
are not meaningful; The queue is not used, therefore,
dsAlgDropNext, dsAlgDropQMeasure, and
dsAlgDropSpecific should be all set to zeroDotZero.
The mQDrop(6) algorithm measures multiple queues for
the drop algorithm. The queues measured are represented
by having dsAlgDropQMeasure referencing a dsMQAlgDropEntry.
Each of the chained dsMQAlgDropEntry is used to describe
the drop algorithm for one of the measured queues."
::= { dsAlgDropEntry 2 }
dsAlgDropNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This selects the next diffserv functional datapath
element to handle traffic for this data path.
The value zeroDotZero in this attribute indicates no
further Diffserv treatment is performed on traffic of
this datapath. Any other value must point to a valid
(pre-existing) instance of one of:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
dsQEntry.
When dsAlgDropType is alwaysDrop(5), this attribute is
Ignored."
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DEFVAL { zeroDotZero }
::= { dsAlgDropEntry 3 }
dsAlgDropQMeasure OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"Points to a PRI to indicate the queues that a drop algorithm
is to monitor when deciding whether to drop a packet.
For alwaysDrop(5), this attribute should be zeroDotZero.
For tailDrop(2), headDrop(3), randomDrop(4), this should
point to an entry in the dsQTable.
For mQDrop(6), this should point to a dsMQAlgDropEntry that
Describe one of the queues being measured for multiple
queue dropper.
The PRI pointed to must exist prior to installing
this dropper element."
::= { dsAlgDropEntry 4 }
dsAlgDropQThreshold OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "Bytes"
STATUS current
DESCRIPTION
"A threshold on the depth in bytes of the queue being
measured at which a trigger is generated to the drop-
ping algorithm, unless dsAlgDropType is alwaysDrop(5)
where this attribute is ignored.
For the tailDrop(2) or headDrop(3) algorithms, this
represents the depth of the queue, pointed to by
dsAlgDropQMeasure, at which the drop action
will take place. Other algorithms will need to define
their own semantics for this threshold."
::= { dsAlgDropEntry 5 }
dsAlgDropSpecific OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"Points to a table entry that provides further detail
regarding a drop algorithm. The PRI pointed to
must exist prior to installing this dropper element.
Entries with dsAlgDropType equal to other(1)
must have this point to an instance of a PRC
defined in another PIB module.
Entries with dsAlgDropType equal to random-
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Drop(4) must have this point to an entry in
dsRandomDropTable.
Entries with dsAlgDropType equal to mQDrop(6) can use this
attribute to reference parameters that is used by all the
queues of the multiple queues being measured.
For all other algorithms, this should take the value
zeroDotZero."
::= { dsAlgDropEntry 6 }
--
-- Multiple Queue Algorithmic Drop Table
--
-- Entries of this table should be referenced by dsAlgDropQMeasure
-- when dsAlgDropType is mQDrop(6) for droppers measuring multiple
-- queues for its drop algorithm.
-- Each entry of the table is used to describe the drop algorithm
-- for a single queue within the multiple queues being measured.
--
-- Entries of this table, dsMQAlgDropEntry, is extended from
-- dsAlgDropEntry, with usage of corresponding parameters the same
-- except:
-- dsAlgDropNext is used to point to the next diffserv
-- functional data path element when the packet is not dropped.
-- dsMQAlgDropExceedNext is used to point to the next
-- dsMQAlgDropEntry for chaining together the multiple
-- dsMQAlgDropEntry's for the multiple queues being measured.
--
dsMQAlgDropTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsMQAlgDropEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The multiple queue algorithmic drop table contains entries
describing each queue being measured for the multiple queue
algorithmic dropper."
::= { dsPolicyClasses 9 }
dsMQAlgDropEntry OBJECT-TYPE
SYNTAX DsMQAlgDropEntry
STATUS current
DESCRIPTION
"An entry describes a process that drops packets
according to some algorithm. Each entry is used for
each of the multiple queues being measured. Each entry
extends the basic dsAlgDropEntry with adding of a
dsMQAlgDropExceedNext attribute.
Further details of the algorithm type are to be found in
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dsAlgDropType and with more detail parameter entry pointed
to by dsMQAlgDropSpecific when necessary."
EXTENDS { dsAlgDropEntry }
UNIQUENESS { dsMQAlgDropExceedNext }
::= { dsMQAlgDropTable 1 }
DsMQAlgDropEntry ::= SEQUENCE {
dsMQAlgDropExceedNext Prid
}
dsMQAlgDropExceedNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"Used for linking of multiple dsMQAlgDropEntry for mQDrop.
A value of zeroDotZero indicates this is the last of a
chain of dsMQAlgDropEntry."
DEFVAL { zeroDotZero }
::= { dsMQAlgDropEntry 1 }
--
-- Random Drop Table
--
dsRandomDropTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsRandomDropEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The random drop table contains entries describing a
process that drops packets randomly. Entries in this
table is intended to be pointed to by dsAlgDropSpecific
when dsAlgDropType is randomDrop(4)."
REFERENCE
"[MODEL] section 7.1.3"
::= { dsPolicyClasses 10 }
dsRandomDropEntry OBJECT-TYPE
SYNTAX DsRandomDropEntry
STATUS current
DESCRIPTION
"An entry describes a process that drops packets
according to a random algorithm."
PIB-INDEX { dsRandomDropPrid }
UNIQUENESS { dsRandomDropMinThreshBytes,
dsRandomDropMinThreshPkts,
dsRandomDropMaxThreshBytes,
dsRandomDropMaxThreshPkts,
dsRandomDropProbMax,
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dsRandomDropWeight,
dsRandomDropSamplingRate
}
::= { dsRandomDropTable 1 }
DsRandomDropEntry ::= SEQUENCE {
dsRandomDropPrid InstanceId,
dsRandomDropMinThreshBytes Unsigned32,
dsRandomDropMinThreshPkts Unsigned32,
dsRandomDropMaxThreshBytes Unsigned32,
dsRandomDropMaxThreshPkts Unsigned32,
dsRandomDropProbMax Unsigned32,
dsRandomDropWeight Unsigned32,
dsRandomDropSamplingRate Unsigned32
}
dsRandomDropPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsRandomDropEntry 1 }
dsRandomDropMinThreshBytes OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "bytes"
STATUS current
DESCRIPTION
"The average queue depth in bytes, beyond which traffic has a
non-zero probability of being dropped."
::= { dsRandomDropEntry 2 }
dsRandomDropMinThreshPkts OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "packets"
STATUS current
DESCRIPTION
"The average queue depth in packets, beyond which traffic has
a non-zero probability of being dropped."
::= { dsRandomDropEntry 3 }
dsRandomDropMaxThreshBytes OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "bytes"
STATUS current
DESCRIPTION
"The average queue depth beyond which traffic has a
probability indicated by dsRandomDropProbMax of being dropped
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or marked. Note that this differs from the physical queue
limit, which is stored in dsAlgDropQThreshold."
::= { dsRandomDropEntry 4 }
dsRandomDropMaxThreshPkts OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "packets"
STATUS current
DESCRIPTION
"The average queue depth beyond which traffic has a
probability indicated by dsRandomDropProbMax of being dropped
or marked. Note that this differs from the physical queue
limit, which is stored in dsAlgDropQThreshold."
::= { dsRandomDropEntry 5 }
dsRandomDropProbMax OBJECT-TYPE
SYNTAX Unsigned32 (0..1000)
STATUS current
DESCRIPTION
"The worst case random drop probability, expressed in drops
per thousand packets.
For example, if every packet may be dropped in the worst case
(100%), this has the value 1000. Alternatively, if in the
worst case one percent (1%) of traffic may be dropped, it has
the value 10."
::= { dsRandomDropEntry 6 }
dsRandomDropWeight OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
STATUS current
DESCRIPTION
"The weighting of past history in affecting the Exponentially
Weighted Moving Average function which calculates the current
average queue depth. The equation uses
dsRandomDropWeight/MaxValue as the coefficient for the new
sample in the equation, and
(MaxValue - dsRandomDropWeight)/MaxValue as the coefficient
of the old value, where, MaxValue is determined via capability
reported by the PEP.
Implementations may further limit the values of
dsRandomDropWeight via the capability tables."
::= { dsRandomDropEntry 7 }
dsRandomDropSamplingRate OBJECT-TYPE
SYNTAX Unsigned32 (0..1000000)
STATUS current
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DESCRIPTION
"The number of times per second the queue is sampled for queue
average calculation. A value of zero means the queue is
sampled approximately each time a packet is enqueued (or
dequeued)."
::= { dsRandomDropEntry 8 }
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--
-- Queue Table
--
--
-- An entry of dsQTable represents a FIFO queue diffserv
-- functional data path element as described in [MODEL] section
-- 7.1.1.
-- Notice the specification of scheduling parameters for a queue
-- as part of the input to a scheduler functional data path
-- element as described in [MODEL] section 7.1.2. This allows
-- building of hierarchical queuing/scheduling.
-- A queue therefore is parameterized by:
-- 1. Which scheduler will service this queue, dsQNext.
-- 2. How the scheduler will service this queue, with respect
-- to all the other queues the same scheduler needs to service,
-- dsQMinRate and dsQMaxRate.
--
-- Notice one or more upstream diffserv functional data path element
-- may share, point to, a dsQTable entry as described in [MODEL]
-- section 7.1.1.
--
dsQTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsQEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The Queue Table enumerates the queues."
::= { dsPolicyClasses 11 }
dsQEntry OBJECT-TYPE
SYNTAX DsQEntry
STATUS current
DESCRIPTION
"An entry in the Queue Table describes a single queue
as a functional data path element."
PIB-INDEX { dsQPrid }
UNIQUENESS { dsQNext,
dsQMinRate,
dsQMaxRate }
::= { dsQTable 1 }
DsQEntry ::= SEQUENCE {
dsQPrid InstanceId,
dsQNext Prid,
dsQMinRate Prid,
dsQMaxRate Prid
}
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dsQPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsQEntry 1 }
dsQNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This selects the next diffserv scheduler. This must point
to a dsSchedulerEntry.
A value of zeroDotZero in this attribute indicates an
incomplete dsQEntry instance. In such a case, the entry
has no operational effect, since it has no parameters to
give it meaning."
::= { dsQEntry 2 }
dsQMinRate OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This Prid indicates the entry in dsMinRateTable
the scheduler, pointed to by dsQNext, should use to service
this queue.
If this value is zeroDotZero, then minimum rate and priority
is unspecified.
If this value is not zeroDotZero then the instance pointed to
must exist prior to installing this entry."
::= { dsQEntry 3 }
dsQMaxRate OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This Prid indicates the entry in dsMaxRateTable
the scheduler, pointed to by dsQNext, should use to service
this queue.
If this value is zeroDotZero, then the maximum rate is the
line speed of the interface.
If this value is not zeroDotZero
then the instance pointed to must exist prior to installing
this entry."
::= { dsQEntry 4 }
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DiffServ QoS Policy Information Base June 2002
--
-- Scheduler Table
--
--
-- The Scheduler Table is used for representing packet schedulers:
-- it provides flexibility for multiple scheduling algorithms, each
-- servicing multiple queues, to be used on the same
-- logical/physical interface of a data path.
--
-- Notice the servicing parameters the scheduler uses is
-- specified by each of its upstream functional data path elements,
-- queues or schedulers of this PIB.
-- The coordination and coherency between the servicing parameters
-- of the scheduler's upstream functional data path elements must
-- be maintained for the scheduler to function correctly.
--
-- The dsSchedulerMinRate and dsSchedulerMaxRate attributes are
-- used for specifying the servicing parameters for output of a
-- scheduler when its downstream functional data path element
-- is another scheduler.
-- This is used for building hierarchical queue/scheduler.
--
-- More discussion of the scheduler functional data path element
-- is in [MODEL] section 7.1.2.
--
dsSchedulerTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsSchedulerEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The Scheduler Table enumerates packet schedulers.
Multiple scheduling algorithms can be used on a given
datapath, with each algorithm described by one
dsSchedulerEntry."
REFERENCE
"[MODEL] section 7.1.2"
::= { dsPolicyClasses 12 }
dsSchedulerEntry OBJECT-TYPE
SYNTAX DsSchedulerEntry
STATUS current
DESCRIPTION
"An entry in the Scheduler Table describing a single
instance of a scheduling algorithm."
PIB-INDEX { dsSchedulerPrid }
UNIQUENESS { dsSchedulerNext,
dsSchedulerMethod,
dsSchedulerMinRate,
dsSchedulerMaxRate }
::= { dsSchedulerTable 1 }
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DsSchedulerEntry ::= SEQUENCE {
dsSchedulerPrid InstanceId,
dsSchedulerNext Prid,
dsSchedulerMethod AutonomousType,
dsSchedulerMinRate Prid,
dsSchedulerMaxRate Prid
}
dsSchedulerPrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsSchedulerEntry 1 }
dsSchedulerNext OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This selects the next diffserv functional datapath
element to handle traffic for this data path.
This attribute normally have a value of zeroDotZero to
indicate no further Diffserv treatment is performed on
traffic of this datapath. The use of zeroDotZero is the
normal usage for the last functional datapath element.
Any value other than zeroDotZero must point to a valid
(pre-existing) instance of one of:
dsSchedulerEntry
dsQEntry,
or:
dsClfrEntry
dsMeterEntry
dsActionEntry
dsAlgDropEntry
This points to another dsSchedulerEntry
for implementation of multiple scheduler methods for
the same data path, and for implementation of
hierarchical schedulers."
DEFVAL { zeroDotZero }
::= { dsSchedulerEntry 2 }
dsSchedulerMethod OBJECT-TYPE
SYNTAX AutonomousType
STATUS current
DESCRIPTION
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DiffServ QoS Policy Information Base June 2002
"The scheduling algorithm used by this Scheduler.
Standard values for generic algorithms:
diffServSchedulerPriority,
diffServSchedulerWRR,
diffServSchedulerWFQ
are specified in the Diffserv MIB.
Additional values may be further specified in other PIBs.
A value of zeroDotZero indicates this is unknown."
REFERENCE
"[MODEL] section 7.1.2"
::= { dsSchedulerEntry 3 }
dsSchedulerMinRate OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This Prid indicates the entry in dsMinRateTable
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."
DEFVAL { zeroDotZero }
::= { dsSchedulerEntry 4 }
dsSchedulerMaxRate OBJECT-TYPE
SYNTAX Prid
STATUS current
DESCRIPTION
"This Prid indicates the entry in dsMaxRateTable
which indicates the maximum output rate from this scheduler.
When more than one maximum rate applies (e.g. a multi-rate
shaper is used), it points to the first of the rate entries.
This attribute is only used when there is more than one level
of scheduler.
When it has the value zeroDotZero, it indicates that no
Maximum rate is imposed."
DEFVAL { zeroDotZero }
::= { dsSchedulerEntry 5 }
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DiffServ QoS Policy Information Base June 2002
--
-- 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 PIB.
-- 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 a Minimum Rate Parameter Table entry.
--
-- The dsMinRatePriority/Absolute/Relative 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.
--
dsMinRateTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsMinRateEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The Minimum Rate Table enumerates individual
sets of scheduling parameter that can be used/reused
by Queues and Schedulers."
::= { dsPolicyClasses 13 }
dsMinRateEntry OBJECT-TYPE
SYNTAX DsMinRateEntry
STATUS current
DESCRIPTION
"An entry in the Minimum Rate Table describes
a single set of scheduling parameter for use by
queues and schedulers."
PIB-INDEX { dsMinRatePrid }
UNIQUENESS { dsMinRatePriority,
dsMinRateAbsolute,
dsMinRateRelative }
::= { dsMinRateTable 1 }
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DsMinRateEntry ::= SEQUENCE {
dsMinRatePrid InstanceId,
dsMinRatePriority Unsigned32,
dsMinRateAbsolute Unsigned32,
dsMinRateRelative Unsigned32
}
dsMinRatePrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsMinRateEntry 1 }
dsMinRatePriority OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
STATUS current
DESCRIPTION
"The priority of this input to the associated scheduler,
relative to the scheduler's other inputs. Higher Priority
value indicates the associated queue/scheduler will get
service first before others with lower Priority values."
::= { dsMinRateEntry 2 }
dsMinRateAbsolute OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "kilobits per second"
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's value is coupled to that
of dsMinRateRelative: changes to one will affect the value
of the other.
[IFMIB] defines ifSpeed as Gauge32 in units of bits per
second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits
per second.
This yields the following equations:
RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000
Where, 1000 is for converting kbps used by RateAbsolute to bps
used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for
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DiffServ QoS Policy Information Base June 2002
RateRelative.
or, if appropriate:
RateRelative =
{ [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } *
1,000
Where, 1000 and 1,000,000 is for converting kbps used by
RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is
for 'in units of 1/1,000 of 1' for RateRelative."
REFERENCE
"ifSpeed, ifHighSpeed from [IFMIB]"
::= { dsMinRateEntry 3 }
dsMinRateRelative OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
STATUS current
DESCRIPTION
"The minimum rate that a downstream scheduler element
should allocate to this queue, relative to the max-
imum rate of the interface as reported by ifSpeed or
ifHighSpeed, in units of 1/1,000 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's value is coupled to that
of dsMinRateAbsolute: changes to one will
affect the value of the other.
[IFMIB] defines ifSpeed as Gauge32 in units of bits per
second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits
per second.
This yields the following equations:
RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000
Where, 1000 is for converting kbps used by RateAbsolute to bps
used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for
RateRelative.
or, if appropriate:
RateRelative =
{ [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } *
1,000
Where, 1000 and 1,000,000 is for converting kbps used by
RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is
for 'in units of 1/1,000 of 1' for RateRelative."
REFERENCE
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DiffServ QoS Policy Information Base June 2002
"ifSpeed, ifHighSpeed from [IFMIB]"
::= { dsMinRateEntry 4 }
--
-- Maximum 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 PIB.
-- 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 Dual Leaky Bucket algorithm, specify their
-- rates using multiple Maximum Rate Parameter Entries with the same
-- dsMaxRateId but different dsMaxRateLevels.
--
-- The dsMaxRateLevel/Absolute/Relative 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.
--
dsMaxRateTable OBJECT-TYPE
SYNTAX SEQUENCE OF DsMaxRateEntry
PIB-ACCESS install
STATUS current
DESCRIPTION
"The Maximum Rate Table enumerates individual
sets of scheduling parameter that can be used/reused
by Queues and Schedulers."
::= { dsPolicyClasses 14 }
dsMaxRateEntry OBJECT-TYPE
SYNTAX DsMaxRateEntry
STATUS current
DESCRIPTION
"An entry in the Maximum Rate Table describes
a single set of scheduling parameter for use by
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DiffServ QoS Policy Information Base June 2002
queues and schedulers."
PIB-INDEX { dsMaxRatePrid }
UNIQUENESS { dsMaxRateId,
dsMaxRateLevel,
dsMaxRateAbsolute,
dsMaxRateRelative,
dsMaxRateThreshold }
::= { dsMaxRateTable 1 }
DsMaxRateEntry ::= SEQUENCE {
dsMaxRatePrid InstanceId,
dsMaxRateId Unsigned32,
dsMaxRateLevel Unsigned32,
dsMaxRateAbsolute Unsigned32,
dsMaxRateRelative Unsigned32,
dsMaxRateThreshold BurstSize
}
dsMaxRatePrid OBJECT-TYPE
SYNTAX InstanceId
STATUS current
DESCRIPTION
"An arbitrary integer index that uniquely identifies an
instance of the class."
::= { dsMaxRateEntry 1 }
dsMaxRateId OBJECT-TYPE
SYNTAX Unsigned32 (0..4294967295)
STATUS current
DESCRIPTION
"An identifier used together with dsMaxRateLevel for
representing a multi-rate shaper. This attribute is used for
associating all the rate attributes of a multi-rate shaper.
Each dsMaxRateEntry of a multi-rate shaper must have the same
value in this attribute. The different rates of a multi-rate
shaper is identified using dsMaxRateLevel.
This attribute uses the value of zero to indicate this
attribute is not used, for single rate shaper."
DEFVAL { 0 }
::= { dsMaxRateEntry 2 }
dsMaxRateLevel OBJECT-TYPE
SYNTAX Unsigned32 (1..32)
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
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DiffServ QoS Policy Information Base June 2002
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.
When the entry is used for a single rate shaper, this
attribute contains a value of one."
DEFVAL { 1 }
::= { dsMaxRateEntry 3 }
dsMaxRateAbsolute OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
UNITS "kilobits per second"
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 max-
imum 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's value is coupled to that
of dsMaxRateRelative: changes to one will
affect the value of the other.
[IFMIB] defines ifSpeed as Gauge32 in units of bits per
second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits
per second.
This yields the following equations:
RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000
Where, 1000 is for converting kbps used by RateAbsolute to bps
used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1'
for RateRelative.
or, if appropriate:
RateRelative =
{ [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } *
1,000
Where, 1000 and 1,000,000 is for converting kbps used by
RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is
for 'in units of 1/1,000 of 1' for RateRelative."
::= { dsMaxRateEntry 4 }
dsMaxRateRelative OBJECT-TYPE
SYNTAX Unsigned32 (1..4294967295)
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DiffServ QoS Policy Information Base June 2002
STATUS current
DESCRIPTION
"The maximum rate that a downstream scheduler element
should allocate to this queue, relative to the max-
imum rate of the interface as reported by ifSpeed or
ifHighSpeed, in units of 1/1,000 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's value is coupled to that
of dsMaxRateAbsolute: changes to one will
affect the value of the other.
[IFMIB] defines ifSpeed as Gauge32 in units of bits per
second, and ifHighSpeed as Gauge32 in units of 1,000,000 bits
per second.
This yields the following equations:
RateRelative = [ (RateAbsolute * 1000) / ifSpeed ] * 1,000
Where, 1000 is for converting kbps used by RateAbsolute to bps
used by ifSpeed, 1,000 is for 'in units of 1/1,000 of 1' for
RateRelative.
or, if appropriate:
RateRelative =
{ [ (RateAbsolute * 1000) / 1,000,000 ] / ifHIghSpeed } *
1,000
Where, 1000 and 1,000,000 is for converting kbps used by
RateAbsolute to 1 million bps used by ifHighSpeed, 1,000 is
for 'in units of 1/1,000 of 1' for RateRelative."
REFERENCE
"ifSpeed, ifHighSpeed from [IFMIB]"
::= { dsMaxRateEntry 5 }
dsMaxRateThreshold OBJECT-TYPE
SYNTAX BurstSize
UNITS "Bytes"
STATUS current
DESCRIPTION
"The number of bytes of queue depth at which the rate of a
multi-rate scheduler will increase to the next output rate. In
the last PRI for such a shaper, this threshold is
ignored and by convention is zero."
REFERENCE
"Adaptive Rate Shaper, RFC 2963"
::= { dsMaxRateEntry 6 }
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DiffServ QoS Policy Information Base June 2002
--
-- Conformance Section
--
dsPolicyPibCompliances
OBJECT IDENTIFIER ::= { dsPolicyPibConformance 1 }
dsPolicyPibGroups
OBJECT IDENTIFIER ::= { dsPolicyPibConformance 2 }
dsPolicyPibCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"Describes the requirements for conformance to the
QoS Policy PIB."
MODULE FRAMEWORK-PIB
MANDATORY-GROUPS {
frwkPrcSupportGroup,
frwkPibIncarnationGroup,
frwkDeviceIdGroup,
frwkCompLimitsGroup,
frwkCapabilitySetGroup,
frwkRoleComboGroup,
frwkIfRoleComboGroup,
frwkBaseFilterGroup,
frwkIpFilterGroup }
OBJECT frwkPibIncarnationLongevity
PIB-MIN-ACCESS notify
DESCRIPTION
"Install support is required if policy expiration is to
be supported."
OBJECT frwkPibIncarnationTtl
PIB-MIN-ACCESS notify
DESCRIPTION
"Install support is required if policy expiration is to
be supported."
MODULE DIFFSERV-PIB -- this module
MANDATORY-GROUPS {
dsPibBaseIfCapsGroup,
dsPibIfClassificationCapsGroup,
dsPibIfAlgDropCapsGroup,
dsPibIfQueueCapsGroup,
dsPibIfSchedulerCapsGroup,
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DiffServ QoS Policy Information Base June 2002
dsPibIfMaxRateCapsGroup,
dsPibIfElmDepthCapsGroup,
dsPibIfElmLinkCapsGroup,
dsPibDataPathGroup,
dsPibClfrGroup,
dsPibClfrElementGroup,
dsPibActionGroup,
dsPibAlgDropGroup,
dsPibQGroup,
dsPibSchedulerGroup,
dsPibMinRateGroup,
dsPibMaxRateGroup }
GROUP dsPibIfMeteringCapsGroup
DESCRIPTION
"This group is mandatory for devices that implement
metering functions."
GROUP dsPibMeterGroup
DESCRIPTION
"This group is mandatory for devices that implement
metering functions."
GROUP dsPibTBParamGroup
DESCRIPTION
"This group is mandatory for devices that implement
token-bucket metering functions."
GROUP dsPibDscpMarkActGroup
DESCRIPTION
"This group is mandatory for devices that implement
DSCP-Marking functions."
GROUP dsPibMQAlgDropGroup
DESCRIPTION
"This group is mandatory for devices that implement
Multiple Queue Measured Algorithmic Drop functions."
GROUP dsPibRandomDropGroup
DESCRIPTION
"This group is mandatory for devices that implement
Random Drop functions."
OBJECT dsClfrId
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
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OBJECT dsClfrElementClfrId
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsClfrElementPrecedence
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsClfrElementNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsClfrElementSpecific
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMeterSucceedNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMeterFailNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMeterSpecific
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsTBParamType
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsTBParamRate
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
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DiffServ QoS Policy Information Base June 2002
OBJECT dsTBParamBurstSize
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsTBParamInterval
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsActionNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsActionSpecific
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsAlgDropType
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsAlgDropNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsAlgDropQMeasure
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsAlgDropQThreshold
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsAlgDropSpecific
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
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DiffServ QoS Policy Information Base June 2002
OBJECT dsRandomDropMinThreshBytes
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsRandomDropMinThreshPkts
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsRandomDropMaxThreshBytes
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsRandomDropMaxThreshPkts
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsRandomDropProbMax
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsRandomDropWeight
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsRandomDropSamplingRate
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsQNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsQMinRate
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
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DiffServ QoS Policy Information Base June 2002
OBJECT dsQMaxRate
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsSchedulerNext
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsSchedulerMethod
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsSchedulerMinRate
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsSchedulerMaxRate
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMinRatePriority
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMinRateAbsolute
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMinRateRelative
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMaxRateId
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
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DiffServ QoS Policy Information Base June 2002
OBJECT dsMaxRateLevel
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMaxRateAbsolute
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMaxRateRelative
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
OBJECT dsMaxRateThreshold
PIB-MIN-ACCESS not-accessible
DESCRIPTION
"Install support is not required."
::= { dsPolicyPibCompliances 1 }
dsPibBaseIfCapsGroup OBJECT-GROUP
OBJECTS {
dsBaseIfCapsDirection
}
STATUS current
DESCRIPTION
"The Base Interface Capability Group defines the PIB
Objects that describe the base for interface capabilities."
::= { dsPolicyPibGroups 1 }
dsPibIfClassificationCapsGroup OBJECT-GROUP
OBJECTS {
dsIfClassificationCapsSpec
}
STATUS current
DESCRIPTION
"The Classification Capability Group defines the PIB
Objects that describe the classification capabilities."
::= { dsPolicyPibGroups 2 }
dsPibIfMeteringCapsGroup OBJECT-GROUP
OBJECTS {
dsIfMeteringCapsSpec
}
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DiffServ QoS Policy Information Base June 2002
STATUS current
DESCRIPTION
"The Metering Capability Group defines the PIB
Objects that describe the metering capabilities."
::= { dsPolicyPibGroups 3 }
dsPibIfAlgDropCapsGroup OBJECT-GROUP
OBJECTS {
dsIfAlgDropCapsType, dsIfAlgDropCapsMQCount
}
STATUS current
DESCRIPTION
"The Algorithmic Dropper Capability Group defines the
PIB Objects that describe the algorithmic dropper
capabilities."
::= { dsPolicyPibGroups 4 }
dsPibIfQueueCapsGroup OBJECT-GROUP
OBJECTS {
dsIfQueueCapsMinQueueSize, dsIfQueueCapsMaxQueueSize,
dsIfQueueCapsTotalQueueSize
}
STATUS current
DESCRIPTION
"The Queueing Capability Group defines the PIB
Objects that describe the queueing capabilities."
::= { dsPolicyPibGroups 5 }
dsPibIfSchedulerCapsGroup OBJECT-GROUP
OBJECTS {
dsIfSchedulerCapsServiceDisc, dsIfSchedulerCapsMaxInputs,
dsIfSchedulerCapsMinMaxRate
}
STATUS current
DESCRIPTION
"The Scheduler Capability Group defines the PIB
Objects that describe the scheduler capabilities."
::= { dsPolicyPibGroups 6 }
dsPibIfMaxRateCapsGroup OBJECT-GROUP
OBJECTS {
dsIfMaxRateCapsMaxLevels
}
STATUS current
DESCRIPTION
"The Max Rate Capability Group defines the PIB
Objects that describe the max rate capabilities."
::= { dsPolicyPibGroups 7 }
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dsPibIfElmDepthCapsGroup OBJECT-GROUP
OBJECTS {
dsIfElmDepthCapsPrc, dsIfElmDepthCapsCascadeMax
}
STATUS current
DESCRIPTION
"The Datapath Element Depth Capability Group defines the PIB
Objects that describe the datapath element depth
capabilities."
::= { dsPolicyPibGroups 8 }
dsPibIfElmLinkCapsGroup OBJECT-GROUP
OBJECTS {
dsIfElmLinkCapsPrc, dsIfElmLinkCapsAttr,
dsIfElmLinkCapsNextPrc
}
STATUS current
DESCRIPTION
"The Datapath Element Linkage Capability Group defines the
PIB Objects that describe the datapath element linkage
capabilities."
::= { dsPolicyPibGroups 9 }
dsPibDataPathGroup OBJECT-GROUP
OBJECTS {
dsDataPathCapSetName, dsDataPathRoles,
dsDataPathIfDirection, dsDataPathStart
}
STATUS current
DESCRIPTION
"The Data Path Group defines the PIB Objects that
describe a data path."
::= { dsPolicyPibGroups 10 }
dsPibClfrGroup OBJECT-GROUP
OBJECTS {
dsClfrId
}
STATUS current
DESCRIPTION
"The Classifier Group defines the PIB Objects that
describe a generic classifier."
::= { dsPolicyPibGroups 11 }
dsPibClfrElementGroup OBJECT-GROUP
OBJECTS {
dsClfrElementClfrId, dsClfrElementPrecedence,
dsClfrElementNext, dsClfrElementSpecific
}
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STATUS current
DESCRIPTION
"The Classifier Group defines the PIB Objects that
describe a generic classifier."
::= { dsPolicyPibGroups 12 }
dsPibMeterGroup OBJECT-GROUP
OBJECTS {
dsMeterSucceedNext, dsMeterFailNext,
dsMeterSpecific
}
STATUS current
DESCRIPTION
"The Meter Group defines the objects used in describ-
ing a generic meter element."
::= { dsPolicyPibGroups 13 }
dsPibTBParamGroup OBJECT-GROUP
OBJECTS {
dsTBParamType, dsTBParamRate,
dsTBParamBurstSize, dsTBParamInterval
}
STATUS current
DESCRIPTION
"The Token-Bucket Parameter Group defines the objects
used in describing a single-rate token bucket meter
element."
::= { dsPolicyPibGroups 14 }
dsPibActionGroup OBJECT-GROUP
OBJECTS {
dsActionNext, dsActionSpecific
}
STATUS current
DESCRIPTION
"The Action Group defines the objects used in
describing a generic action element."
::= { dsPolicyPibGroups 15 }
dsPibDscpMarkActGroup OBJECT-GROUP
OBJECTS {
dsDscpMarkActDscp
}
STATUS current
DESCRIPTION
"The DSCP Mark Action Group defines the objects used
in describing a DSCP Marking Action element."
::= { dsPolicyPibGroups 16 }
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DiffServ QoS Policy Information Base June 2002
dsPibAlgDropGroup OBJECT-GROUP
OBJECTS {
dsAlgDropType, dsAlgDropNext,
dsAlgDropQMeasure, dsAlgDropQThreshold,
dsAlgDropSpecific
}
STATUS current
DESCRIPTION
"The Algorithmic Drop Group contains the objects that
describe algorithmic dropper operation and configura-
tion."
::= { dsPolicyPibGroups 17 }
dsPibMQAlgDropGroup OBJECT-GROUP
OBJECTS {
dsMQAlgDropExceedNext
}
STATUS current
DESCRIPTION
"The Multiple Queue Measured Algorithmic Drop Group
contains the objects that describe multiple queue
measured algorithmic dropper operation and configuration."
::= { dsPolicyPibGroups 18 }
dsPibRandomDropGroup OBJECT-GROUP
OBJECTS {
dsRandomDropMinThreshBytes,
dsRandomDropMinThreshPkts,
dsRandomDropMaxThreshBytes,
dsRandomDropMaxThreshPkts,
dsRandomDropProbMax,
dsRandomDropWeight,
dsRandomDropSamplingRate
}
STATUS current
DESCRIPTION
"The Random Drop Group augments the Algorithmic Drop Group
for random dropper operation and configuration."
::= { dsPolicyPibGroups 19 }
dsPibQGroup OBJECT-GROUP
OBJECTS {
dsQNext, dsQMinRate, dsQMaxRate
}
STATUS current
DESCRIPTION
"The Queue Group contains the objects that describe
an interface type's queues."
::= { dsPolicyPibGroups 20 }
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dsPibSchedulerGroup OBJECT-GROUP
OBJECTS {
dsSchedulerNext, dsSchedulerMethod,
dsSchedulerMinRate, dsSchedulerMaxRate
}
STATUS current
DESCRIPTION
"The Scheduler Group contains the objects that
describe packet schedulers on interface types."
::= { dsPolicyPibGroups 21 }
dsPibMinRateGroup OBJECT-GROUP
OBJECTS {
dsMinRatePriority,
dsMinRateAbsolute, dsMinRateRelative
}
STATUS current
DESCRIPTION
"The Minimum Rate Group contains the objects
that describe packet schedulers' parameters on interface
types."
::= { dsPolicyPibGroups 22 }
dsPibMaxRateGroup OBJECT-GROUP
OBJECTS {
dsMaxRateId, dsMaxRateLevel, dsMaxRateAbsolute,
dsMaxRateRelative, dsMaxRateThreshold
}
STATUS current
DESCRIPTION
"The Maximum Rate Group contains the objects
that describe packet schedulers' parameters on interface
types."
::= { dsPolicyPibGroups 23 }
END
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DiffServ QoS Policy Information Base June 2002
9. Acknowledgments
This PIB builds on all the work that has gone into the Informal
Management Model for Diffserv Routers and Management Information
Base for the Differentiated Services Architecture.
It has been developed with the active involvement of many people,
but most notably Ravi Sahita and Walter Weiss.
10. Security Considerations
The information contained in a PIB when transported by the COPS
protocol [COPS-PR] may be sensitive, and its function of
provisioning a PEP requires that only authorized communication take
place.
In this PIB, there are no PRCs which are sensitive in their own
right, such as passwords or monetary amounts. But there are a
number of PRCs in this PIB 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 traffic. These PRCs have a PIB-
ACCESS clause of install:
dsDataPathTable, dsClfrTable, dsClfrElementTable, dsMeterTable,
dsTBParamTable, dsActionTable, dsDscpMarkActTable, dsAlgDropTable,
dsMQAlgDropTable, dsRandomDropTable, dsQTable, dsSchedulerTable,
dsMinRateTable, dsMaxRateTable
Malicious altering of the above PRCs may affect the Diffserv
behavior of the device being provisioned.
Malicious access of the above PRCs exposes policy information
concerning how the device is provisioned.
This PIB also contain PRCs with PIB-ACCESS clause of notify:
dsBaseIfCapsTAble, dsIfClassificationCapsTable,
dsIfMeteringCapsTable, dsIfAlgDropCapsTable, dsIfQueueCapsTable,
dsIfSchedulerCapsTable, dsIfMaxRateCapsTable, dsIfElmDepthCapsTable,
dsIfElmLinkCapsTable
Malicious access of the above PRCs exposes information concerning
the device being provisioned.
The use of IPSEC between PDP and PEP, as described in [COPS],
provides the necessary protection.
11. Intellectual Property Considerations
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DiffServ QoS Policy Information Base June 2002
The IETF has been notified of intellectual property rights claimed
in regard to some or all of the specification contained in this
document. For more information consult the online list of claimed
rights.
12. RFC Editor Considerations
Some IETF documents this document references are in the IESG last
call stage. This document references them as internet drafts.
Please use their corresponding RFC numbers prior to publishing of
this document as a RFC. The referenced IETF documents are [FR-PIB],
[MODEL], and [DS-MIB].
13. IANA Considerations
This document describes the dsPolicyPib Policy Information Base
(PIB) modules for standardization under the "pib" branch registered
with IANA. An IANA assigned PIB number is requested under the "pib"
branch.
[SPPI] PIB SUBJECT-CATEGORIES are mapped to COPS Client Types.
IANA Considerations for SUBJECT-CATEGORIES follow the same
requirements as specified in [COPS] IANA Considerations for COPS
Client Types. The DiffServ QoS PIB defines a new COPS Client Type
in the Standards space, hence that needs a COPS client type
assignment from IANA (as described in [COPS] IANA Considerations).
IANA must also update the registry for COPS Client Types as a
result.
14. Authors' Addresses
Michael Fine
Atheros Communications
529 Almanor Ave
Sunnyvale, CA 94085 USA
Phone: +1 408 773 5324
Email: mfine@atheros.com
Keith McCloghrie
Cisco Systems, Inc.
170 West Tasman Drive
San Jose, CA 95134-1706 USA
Phone: +1 408 526 5260
Email: kzm@cisco.com
John Seligson
Nortel Networks, Inc.
4401 Great America Parkway
Santa Clara, CA 95054 USA
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DiffServ QoS Policy Information Base June 2002
Phone: +1 408 495 2992
Email: jseligso@nortelnetworks.com
Kwok Ho Chan
Nortel Networks, Inc.
600 Technology Park Drive
Billerica, MA 01821 USA
Phone: +1 978 288 8175
Email: khchan@nortelnetworks.com
Scott Hahn
Intel
2111 NE 25th Avenue
Hillsboro, OR 97124 USA
Phone: +1 503 264 8231
Email: scott.hahn@intel.com
Carol Bell
Intel
2111 NE 25th Avenue
Hillsboro, OR 97124 USA
Phone: +1 503 264 8491
Email: carol.a.bell@intel.com
Andrew Smith
Harbour Networks
Jiuling Building
21 North Xisanhuan Ave.
Beijing, 100089, PRC
Email: ah_smith@acm.org
Francis Reichmeyer
PFN, Inc.
University Park at MIT
26 Landsdowne Street
Cambridge, MA 02139
Phone: +1 617 494 9980
Email: franr@pfn.com
15. Normative References
[COPS]
Boyle, J., Cohen, R., Durham, D., Herzog, S., Rajan, R., and
A. Sastry, "The COPS (Common Open Policy Service) Protocol"
RFC 2748, January 2000.
[COPS-PR]
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DiffServ QoS Policy Information Base June 2002
K. Chan, D. Durham, S. Gai, S. Herzog, K. McCloghrie,
F. Reichmeyer, J. Seligson, A. Smith, R. Yavatkar,
"COPS Usage for Policy Provisioning,", RFC 3084, March 2001
[SPPI]
K. McCloghrie, M. Fine, J. Seligson, K. Chan, S. Hahn,
R. Sahita, A. Smith, F. Reichmeyer, "Structure of Policy
Provisioning Information",
RFC 3159,August 2001.
[DSARCH]
M. Carlson, W. Weiss, S. Blake, Z. Wang, D. Black, and
E. Davies, "An Architecture for Differentiated Services",
RFC 2475, December 1998
[DSFIELD]
K. Nichols, S. Blake, F. Baker, D. Black, "Definition of the
Differentiated Services Field (DS Field) in the IPv4 and
IPv6 Headers", RFC 2474, December 1998.
[FR-PIB]
M. Fine, K. McCloghrie, J. Seligson, K. Chan, S. Hahn,
R. Sahita, A. Smith, F. Reichmeyer, "Framework Policy
Information Base",
Internet Draft <draft-ietf-rap-frameworkpib-07.txt>,
January 2002.
[RAP-FRAMEWORK]
R. Yavatkar, D. Pendarakis, "A Framework for
Policy-based Admission Control", RFC 2753, January 2000.
[SNMP-SMI]
K. McCloghrie, D. Perkins, J. Schoenwaelder, J. Case,
M. Rose and S. Waldbusser, "Structure of Management
Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999.
[MODEL]
Y. Bernet, S. Blake, D. Grossman, A. Smith "An Informal
Management Model for Diffser Routers",
Internet Draft <draft-ietf-diffserv-model-06.txt>,
February 2001.
[IFMIB]
K. McCloghrie, F. Kastenholz, "The Interfaces Group MIB",
RFC 2863, June 2000.
[DS-MIB]
F. Baker, K. Chan, A. Smith, "Management Information Base for
the Differentiated Services Architecture",
draft-ietf-diffserv-mib-16.txt, November 2001
[ACTQMGMT]
V. Firoiu, M. Borden "A Study of Active Queue Management for
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DiffServ QoS Policy Information Base June 2002
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]
J. Heinanen, F. Baker, W. Weiss, J. Wroclawski, "Assured
Forwarding PHB Group.", RFC 2597, June 1999.
[EF-PHB]
V. Jacobson, K. Nichols, K. Poduri, "An Expedited Forwarding
PHB." RFC 2598, June 1999.
[INTSERVMIB]
F. Baker, J. Krawczyk, A. Sastry, "Integrated Services
Management Information Base using SMIv2", RFC 2213,
September 1997.
[QUEUEMGMT]
B. Braden et al., "Recommendations on Queue Management and
Congestion Avoidance in the Internet", RFC 2309, April 1998.
[SRTCM]
J. Heinanen, R. Guerin, "A Single Rate Three Color Marker",
RFC 2697, September 1999.
[TRTCM]
J. Heinanen, R. Guerin, "A Two Rate Three Color Marker",
RFC 2698, September 1999.
[TSWTCM]
W. Fang, N. Seddigh, B. Nandy "A Time Sliding Window Three
Colour Marker", RFC 2859, June 2000.
[RFC2026]
Bradner, S., "The Internet Standards Process -- Revision 3",
BCP 9, RFC 2026, October 1996.
[SHAPER]
"A Rate Adaptive Shaper for Differentiated Services",
RFC 2963, October 2000.
[POLTERM]
A. Westerinen, J. Schnizlein, J. Strassner, M. Scherling,
B. Quinn, S. Herzog, A. Huynh, M. Carlson, J. Perry, S.
Waldbusser, "Terminology for Policy-Based Management",
RFC 3198, November 2001.
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DiffServ QoS Policy Information Base June 2002
16. Full Copyright
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.
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