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Internet Engineering Task Force                                 F. Baker
Diffserv Working Group                                     Cisco Systems
INTERNET-DRAFT                                                   K. Chan
Expires December 2001                                    Nortel Networks
draft-ietf-diffserv-mib-10.txt                                  A. Smith
                                                        Allegro Networks
                                                               June 2001

                  Management Information Base for the
                  Differentiated Services Architecture


Status of this Memo

This document is an Internet-Draft and is in full conformance with all
provisions of Section 10 of RFC 2026. 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- Drafts.

Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet Drafts as reference material
or to cite them other than as "work in progress."

The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt. The list of Internet-Draft
Shadow Directories can be accessed at http://www.ietf.org/shadow.html.

This document is a product of the IETF's Differentiated Services Working
Group.  Comments should be addressed to WG's mailing list at
Differentiated Services@ietf.org. The charter for Differentiated
Services may be found at
http://www.ietf.org/html.charters/Differentiated Services-charter.html

Copyright (C) The Internet Society (2000). All Rights Reserved.
Distribution of this memo is unlimited.


Abstract

This memo describes an SMIv2 MIB for a device implementing the
Differentiated Services Architecture [DSARCH], described in detail by
the Informal Management Model for Differentiated Services Routers
[MODEL].







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1.  The SNMP Management Framework

The SNMP Management Framework presently consists of five major
components:

 o      An overall architecture, described in RFC 2571 [1].

 o      Mechanisms for describing and naming objects and events for the
        purpose of management. The first version of this Structure of
        Management Information (SMI) is called SMIv1 and described in
        RFC 1155 [2], RFC 1212 [3] and RFC 1215 [4].  The second
        version, called SMIv2, is described in RFC 2578 [5], RFC 2579
        [6] and RFC 2580 [7].

 o      Message protocols for transferring management information. The
        first version of the SNMP message protocol is called SNMPv1 and
        described in RFC 1157 [8]. A second version of the SNMP message
        protocol, which is not an Internet standards track protocol, is
        called SNMPv2c and described in RFC 1901 [9] and RFC 1906 [10].
        The third version of the message protocol is called SNMPv3 and
        described in RFC 1906 [10], RFC 2572 [11] and RFC 2574 [12].

 o      Protocol operations for accessing management information. The
        first set of protocol operations and associated PDU formats is
        described in RFC 1157 [8]. A second set of protocol operations
        and associated PDU formats is described in RFC 1905 [13].

 o      A set of fundamental applications described in RFC 2573 [14] and
        the view-based access control mechanism described in RFC 2575
        [15].

A more detailed introduction to the current SNMP Management Framework
can be found in RFC 2570 [16].

Managed objects are accessed via a virtual information store, termed the
Management Information Base or MIB. Objects in the MIB are defined using
the mechanisms defined in the SMI.

This memo specifies a MIB module that is compliant to the SMIv2. A MIB
conforming to the SMIv1 can be produced through the appropriate
translations.  The resulting translated MIB must be semantically
equivalent, except where objects or events are omitted because no
translation is possible (use of Counter64). Some machine-readable
information in SMIv2 will be converted into textual descriptions in
SMIv1 during the translation process. However, this loss of machine
readable information is not considered to change the semantics of the
MIB.





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2.  Relationship to other working group documents

The working group and related working groups developed other documents,
notably the Informal Management Model and the policy configuration
paradigm of SNMPCONF.  The relationship between the MIB and those
documents is clarified here.

2.1.  Relationship to the Informal Management Model for Differentiated
Services Router

This MIB is similar in design to [MODEL], although it can be used to
build functional data paths that the model would not well describe.  The
model conceptually describes ingress and egress interfaces of an n-port
router, which may find some interfaces at a network edge and others
facing into the network core.  It describes the configuration and
management of a Differentiated Services interface in terms of one or
more Traffic Conditioning Block (TCB), each containing, arranged in the
specified order, by definition, zero or more classifiers, meters,
actions, algorithmic droppers, queues and schedulers.  Traffic may be
classified, and classified traffic may be metered.  Each stream of
traffic identified by a combination of classifiers and meters may have
some set of actions performed on it; it may have dropping algorithms
applied and it may ultimately be stored into a queue before being
scheduled out to its next destination, either onto a link or to another
TCB.  At times, the treatment for a given packet must have any of those
elements repeated.  [MODEL] models this by cascading multiple TCBs,
while this MIB describes the policy by directly linking the functional
data path elements.

The MIB represents this cascade by following the "Next" attributes of
the various elements.  They indicate what the next step in
Differentiated Services processing will be, whether it be a classifier,
meter, action, algorithmic dropper, queue, scheduler or a decision to
now forward a packet.

The higher level concept of a TCB is not required in the
parameterization or in the linking together of the individual elements,
hence it is not used in the MIB itself and is only mentioned in the text
for relating the MIB with the [MODEL].  Rather, the MIB models the
individual elements that make up the TCBs.

This MIB uses the notion of a Data Path to indicate the Differentiated
Services processing a packet may experience.  The Data Path a packet
will initially follow is an attribute of the interface in question.  The
Data Path Start Table provides a starting point for each direction
(ingress or egress) on each interface.  A Data Path Table Entry
indicates the first of possibly multiple elements that will apply





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Differentiated Services treatment to the packet.


2.2.  Relationship to other MIBs and Policy Management

This MIB provides for direct reporting and manipulation of detailed
functional elements.  These elements consist of a structural element and
one or more parameter-bearing elements.  While this can be cumbersome,
it allows the reuse of parameters.  For example, a service provider may
offer three varieties of contracts, and configure three parameter
elements.  Each such data path on the system may then refer to these
sets of parameters.  The diffServDataPathTable couples each direction on
each interface with the specified data path linkage.  The concept of
"interface" is as defined by InterfaceIndex/ifIndex of the IETF
Interfaces MIB [IFMIB].

Other MIBs and data structure definitions for policy management
mechanisms other than SNMP/SMIv2 are likely to exist in the future for
the purposes of abstracting the model in other ways.

In particular, abstractions in the direction of less detailed
definitions of Differentiated Services functionality are likely e.g.
some form of "Per-Hop Behavior"-based definition involving a template of
detailed object values which is applied to specific instances of objects
in this MIB semi-automatically.

Another possible direction of abstraction is one using a concept of
"roles" (often, but not always, applied to interfaces).  In this case,
it may be possible to re-use the object definitions in this MIB,
especially the parameterization tables.  The Data Path table will help
in the reuse of the data path linkage tables by having the interface
specific information centralized, allowing easier mechanical replacement
of ifIndex by some sort of "roleIndex".  This work is ongoing.


3.  MIB Overview

The Differentiated Services Architecture does not specify how an
implementation should be assembled.  The [MODEL] describes a general
approach to implementation design, or to user interface design.  Its
components could, however, be assembled in a different way.  Traffic
conforming to a meter might be run through a second meter, for example,
or reclassified.

This MIB models the same functional data path elements, allowing the
network manager to assemble them in any fashion that meets the relevant
policy.  These data path elements include Classifiers, Meters, Actions





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of various sorts, Queues, and Schedulers.

In many of these tables, a distinction is drawn between the structure of
the policy (do this, then do that) and the parameters applied to
specific policy elements.  This is to facilitate configuration, if the
MIB is used for that.  The concept is that a set of parameters, such as
the values that describe a specific token bucket, might be configured
once and applied to many interfaces.

The RowPointer Textual Convention is therefore used in two ways in this
MIB.  It is defined for the purpose of connecting an object to an entry
dynamically; the RowPointer object identifies the first object in the
target Entry, and in so doing points to the entire entry.  In this MIB,
it is used as a connector between successive functional data path
elements, and as the link between the policy structure and the
parameters that are used.  When used as a connector, it says what
happens "next"; what happens to classified traffic, to traffic
conforming or not conforming to a meter, and so on.  When used to
indicate the parameters applied in a policy, it says "specifically" what
is meant; the structure points to the parameters of its policy.

The use of RowPointers as connectors allows for the simple extension of
the MIB.  The RowPointers, whether "next" or "specific", may point to
Entries defined in other MIB modules.  For example, the only type of
meter defined in this MIB is a token bucket meter; if another type of
meter is required, a proprietary MIB or another standard MIB could be
defined describing that type of meter, and diffServMeterSpecific could
point to it.  Similarly, if a new action is required, the "next" pointer
of the previous functional datapath element could point to an Entry
defined in a proprietary MIB or one defined in another standard.


3.1.  Processing Path

An interface has an ingress and an egress direction, and will generally
have a different policy in each direction.  As traffic enters an edge
interface, it may be classified, metered, counted, and marked.  Traffic
leaving the same interface might be remarked according to the contract
with the next network, queued to manage the bandwidth, and so on.  As
[MODEL] points out, the functional datapath elements used on ingress and
egress are of the same type, but may be structured in very different
ways to implement the relevant policies.










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3.1.1.  diffServDataPathTable - The Data Path Table

Therefore, when traffic arrives at an ingress or egress interface, the
first step in applying the policy is determining what policy applies.
This MIB does that by providing a table of pointers to the first
functional data path element, indexed by interface and direction on that
interface.  The content of the diffServDataPathEntry is a single
RowPointer, which points to that functional data path element.

When diffServDataPathStart in a direction on an interface is undefined
or is set to zeroDotZero, the implication is that there is no specific
policy to apply; the manufacturer's default is used.


3.2.  Classifier

Classifiers are used to differentiate among types of traffic.  In the
Differentiated Services architecture, one usually discusses a behavior
aggregate identified by the application of one or more Differentiated
Services Code Points (DSCPs).  However, especially at network edges
(which include hosts and first hop routers serving hosts), traffic may
arrive unmarked or the marks may not be trusted.  In these cases, one
applies a Multi-Field Classifier, which may select an aggregate as
coarse as "all traffic", as fine as a specific microflow identified by
IP Addresses, IP Protocol, and TCP/UDP ports, or variety of slice in
between.

Classifiers can be simple or complex.  In a core interface, one would
expect to find simple behavior aggregate classification to be used.
However, in an edge interface, one might first ask what application is
being used, meter the arriving traffic, and then apply various policies
to the non-conforming traffic depending on the Autonomous System number
advertising the destination address.  To accomplish such a thing,
traffic must be classified, metered, and then reclassified.  To this
end, the MIB defines separate classifiers, which may be applied at any
point in processing, and may have different content as needed.

The MIB also allows for ambiguous classification in a structured
fashion.  In the end, traffic classification must be unambiguous; we
must know for certain what policy to apply to any given packet.
However, writing an unambiguous specification is often tedious, while
writing a specification in steps that permits and excludes various kinds
of traffic may be simpler and more intuitive.  In such a case, the
classification "steps" are enumerated; all classification elements of
one precedence are applied as if in parallel, and then all
classification elements of the next precedence.






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This MIB defines a single classifier parameter entry, the Six-Tuple
Classifier.  A degenerate case of this multi-field classifier is a
Behavior Aggregate classifier.  Other classifiers may be defined in
other MIB modules, to select traffic from a given layer two neighbor or
a given interface, traffic whose addresses belong to a given BGP
Community or Autonomous System, and so on.


3.2.1.  diffServClfrElementTable - The Classifier Element Table

A classifier consists of classifier elements.  A classifier element
identifies a specific set of traffic that forms part of a behavior
aggregate; other classifier elements within the same classifier may
identify other traffic that also falls into the behavior aggregate.  For
example, in identifying AF traffic for the aggregate AF1, one might
implement separate classifier elements for AF11, AF12, and AF13 within
the same classifier and pointing to the same subsequent meter.

Generally, one would expect Data Path Entry to point to a classifier
(which is to say, the first of a set of one or more classifier
elements), although it may point to something else when appropriate.
Reclassification in a functional data path is achieved by pointing to
another Classifier Entry when appropriate.

A classifier element is a structural element, indexed by classifier ID
and element ID.  It has a precedence value, allowing for structured
ambiguity as described above, a "specific" pointer that identifies what
rule is to be applied, and a "next" pointer directing traffic matching
the classifier to the next functional data path element.  If the "next"
pointer is zeroDotZero, the indication is that there is no further
differentiated services processing for this behavior aggregate.  If the
"specific" pointer is zeroDotZero, however, the device is misconfigured.
In such a case, the classifier element should be operationally treated
as if it were not present.

When the MIB is used for configuration, diffServClfrNextFree always
contains a legal value for diffServClfrId that is not currently used in
the system's configuration.  The Network Management Application reads
the variable and uses the value read in a create-and-go or a create-
and-wait SET.  When the SET is performed, the agent must determine
whether the value is indeed still unused; two network managers may
attempt to create a configuration entry simultaneously and use the same
value.  If it is currently unused, the SET succeeds and the agent
changes the value of diffServClfrNextFree according to an agent-specific
algorithm.  If the value is in use, however, the SET fails.  The network
manager must re-read diffServClfrNextFree to obtain a useful value.






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Likewise, when the MIB is used for configuration,
diffServClfrElementNextFree always contains a legal value for
diffServClfrElementClfrId that is not currently used in the system's
configuration.  The Network Management Application reads the variable
and uses the value read in a create-and-go or a create-and-wait SET.
When the SET is performed, the agent must determine whether the value is
indeed still unused; two network managers may attempt to create a
configuration entry simultaneously and use the same value.  If it is
currently unused, the SET succeeds and the agent changes the value of
diffServClfrElementNextFree according to an agent-specific algorithm.
If the value is in use, however, the SET fails.  The network manager
must re-read diffServClfrElementNextFree to obtain a useful value.


3.2.2.  diffServSixTupleClfrTable - The Six-Tuple Classifier Table

This MIB defines a single parameter type for classification, the Six-
Tuple Classifier.  As a parameter, a filter may be specified once and
applied to many interfaces, using diffServClfrElementSpecific.  This
classifier matches:

 o      IP source address prefix, including host, CIDR Prefix, and "any
        source address"

 o      IP destination address prefix, including host, CIDR Prefix, and
        "any destination address"

 o      IP protocol or "any"

 o      TCP/UDP/SCTP source port range, including "any"

 o      TCP/UDP/SCTP destination port range, including "any"

 o      Differentiated Services Code Point

In that ranges or "any" are defined in each case, clearly a wide variety
of filters can be constructed.  The Differentiated Services Behavior
Aggregate filter is a special case of this filter.

Other MIB modules may define similar filters in the same way.  For
example, a filter for Ethernet information might define source and
destination MAC addresses of "any", Ethernet Packet Type, IEEE 802.2
SAPs, and IEEE 802.1 priorities.  A filter related to policy routing
might be structured like the diffServSixTupleClfrTable, but containing
the BGP Communities of the source and destination prefix rather than the
prefix itself, meaning "any prefix in this community".  For such a
filter, a table similar to diffServSixTupleClfrTable is constructed, and





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diffServClfrElementSpecific configured to point to it.

When the MIB is used for configuration, diffServSixTupleClfrNextFree
always contains a legal value for diffServSixTupleClfrId that is not
currently used in the system's configuration.  The Network Management
Application reads the variable and uses the value read in a create-
and-go or a create-and-wait SET.  When the SET is performed, the agent
must determine whether the value is indeed still unused; two network
managers may attempt to create a configuration entry simultaneously and
use the same value.  If it is currently unused, the SET succeeds and the
agent changes the value of diffServSixTupleClfrNextFree according to an
agent-specific algorithm.  If the value is in use, however, the SET
fails.  The network manager must re-read diffServSixTupleClfrNextFree to
obtain a useful value.


3.3.  Metering Traffic

As discussed in [MODEL], a "meter" and a "shaper" are functions that
operate on opposing ends of a link.  A shaper schedules traffic for
transmission at specific times in order to approximate a particular line
speed or combination of line speeds.  In its simplest form, if the
traffic stream contains constant sized packet, it might transmit one
packet per unit time to build the equivalent of a CBR circuit.  However,
various factors intervene to make the approximation inexact; multiple
classes of traffic may occasionally schedule their traffic and the same
time, the variable length nature of IP traffic may introduce variation,
and factors in the link or physical layer may change traffic timing.  A
"meter" integrates the arrival rate of traffic and determines whether
the shaper at the far end was correctly applied, or whether the behavior
of the application in question is naturally close enough to such
behavior to be acceptable under a given contract.

A common type of meter is a Token Bucket meter, such as [SRTCM] or
[TRTCM].  This type of meter assumes the use of a shaper at a previous
node; applications which send at a constant rate when sending may
conform if the token bucket is properly specified.  It specifies the
acceptable arrival rate and quantifies the acceptable variability, often
by specifying a burst size or an interval; since rate = quantity/time,
specifying any two of those parameters implies the third, and a large
interval provides for a forgiving system.  Multiple rates may be
specified, as in AF, such that a subset of the traffic (up to one rate)
is accepted with one set of guarantees, and traffic in excess of that
but below another rate has a different set of guarantees.  Other types
of meters exist as well.

One use of a meter is when a service provider sells at most a certain





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bit rate to one of its customers, and wants to drop the excess.  In such
a case, the fractal nature of normal Internet traffic must be reflected
in large burst intervals, as TCP frequently sends packet pairs or larger
bursts, and responds poorly when more than one packet in a round trip
interval is dropped.  Applications like FTP contain the effect by simply
staying below the target bit rate; this type of configuration very
adversely affects transaction applications like HTTP, however.  Another
use of a meter is in the AF specification, in which excess traffic is
marked with a related DSCP and subjected to slightly more active queue
depth management.  The application is not sharply limited to a
contracted rate in such a case, but can be readily contained should its
traffic create a burden.


3.3.1.  diffServMeterTable - The Meter Table

The Meter Table is a structural table, specifying a specific functional
data path element.  Its entry consists essentially of three RowPointers
- a "succeed" pointer, for traffic conforming to the meter, a "fail"
pointer, for traffic not conforming, and a "specific" pointer, to
identify the parameters in question.  This structure is a bow to SNMP's
limitations; it would be better to have a structure with N rates and N+1
"next" pointers, with a single algorithm specified.  In this case,
multiple meter entries connected by the "fail" link are understood to
contain the parameters for a specified algorithm, and traffic conforming
to a given rate follows their "succeed" paths.  Within this MIB, only
Token Bucket parameters are specified; other varieties of meters may be
designed in other MIB modules.

When the MIB is used for configuration, diffServMeterNextFree always
contains a legal value for diffServMeterId that is not currently used in
the system's configuration.  The Network Management Application reads
the variable and uses the value read in a create-and-go or a create-
and-wait SET.  When the SET is performed, the agent must determine
whether the value is indeed still unused; two network managers may
attempt to create a configuration entry simultaneously and use the same
value.  If it is currently unused, the SET succeeds and the agent
changes the value of diffServMeterNextFree according to an agent-
specific algorithm.  If the value is in use, however, the SET fails.
The network manager must re-read diffServMeterNextFree to obtain a
useful value.


3.3.2.  diffServTBParamTable - The Token Bucket Parameters Table

The Token Bucket Parameters Table is a set of parameters that define a
Token Bucket Meter.  As a parameter, a token bucket may be specified





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once and applied to many interfaces, using diffServMeterSpecific.
Specifically, several modes of [SRTCM] and [TRTCM] are addressed.  Other
varieties of meters may be specified in other MIB modules.

In general, if a Token Bucket has N rates, it has N+1 potential outcomes
- the traffic stream is slower than and therefore conforms to all of the
rates, it fails the first few but is slower than and therefore conforms
to the higher rates, or it fails all of them.  As such, multi-rate
meters should specify those rates in montonically increasing order,
passing through the diffServMeterFailNext from more committed to more
excess rates, and finally falling through diffServMeterFailNext to the
set of actions that apply to traffic which conforms to none of the
specified rates.  DiffServTBParamType in the first entry indicates the
algorithm being used.  At each rate, diffServTBParamRate is derivable
from diffServTBParamBurstSize and diffServTBParamInterval; a superior
implementation will allow the configuration of any two of
diffServTBParamRate, diffServTBParamBurstSize, and
diffServTBParamInterval, and respond "badValue" if all three are
specified but are not mathematically related.

When the MIB is used for configuration, diffServTBParamNextFree always
contains a legal value for diffServTBParamId that is not currently used
in the system's configuration.  The Network Management Application reads
the variable and uses the value read in a create- and-go or a create-
and-wait SET.  When the SET is performed, the agent must determine
whether the value is indeed still unused; two network managers may
attempt to create a configuration entry simultaneously and use the same
value.  If it is currently unused, the SET succeeds and the agent
changes the value of diffServTBParamNextFree according to an agent-
specific algorithm.  If the value is in use, however, the SET fails.
The network manager must re-read diffServTBParamNextFree to obtain a
useful value.


3.4.  Actions applied to packets

"Actions" are the things a differentiated services interface PHB may do
to a packet in transit.  At minimum, such a policy might calculate
statistics on traffic in various configured classes, mark it with a
DSCP, drop it, or enqueue it before passing it on for other processing.

Actions are composed of a structural element, the diffServActionTable,
and various component action entries that may be applied.  In the case
of the Algorithmic Dropper, an additional parameter table may be
specified to control Active Queue Management, as defined in [RED93] and
other AQM specifications.






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3.4.1.  diffServActionTable - The Action Table

The action table identifies sequences of actions to be applied to a
packet.  Successive actions are chained through diffServActionNext,
ultimately terminating in zeroDotZero (indicating that the policy is
complete), a pointer to a queue, or a pointer to some other functional
data path element.

When the MIB is used for configuration, diffServActionNextFree always
contains a legal value for diffServActionId that is not currently used
in the system's configuration.  The Network Management Application reads
the variable and uses the value read in a create- and-go or a create-
and-wait SET.  When the SET is performed, the agent must determine
whether the value is indeed still unused; two network managers may
attempt to create a configuration entry simultaneously and use the same
value.  If it is currently unused, the SET succeeds and the agent
changes the value of diffServActionNextFree according to an agent-
specific algorithm.  If the value is in use, however, the SET fails.
The network manager must re-read diffServActionNextFree to obtain a
useful value.


3.4.2.  diffServCountActTable - The Count Action Table

The count action accumulates statistics pertaining to traffic passing
through a given path through the policy.  It is intended to be useful
for usage-based billing, for statistical studies, or for analysis of the
behavior of a policy in a given network.  The objects in the Count
Action are various counters and a discontinuity time.  The counters
display the number of packets and bytes encountered on the path since
the discontinuity time.  They share the same discontinuity time.

The designers of this MIB expect that every path through a policy should
have a corresponding counter.  In early versions, it was impossible to
configure an action without implementing a counter, although the current
design makes them in effect the network manager's option, as a result of
making actions consistent in structure and extensible.  The assurance of
proper debug and accounting is therefore left with the policy designer.

When the MIB is used for configuration, diffServCountActNextFree always
contains a legal value for diffServCountActId that is not currently used
in the system's configuration.  The Network Management Application reads
the variable and uses the value read in a create- and-go or a create-
and-wait SET.  When the SET is performed, the agent must determine
whether the value is indeed still unused; two network managers may
attempt to create a configuration entry simultaneously and use the same
value.  If it is currently unused, the SET succeeds and the agent





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changes the value of diffServCountActNextFree according to an agent-
specific algorithm.  If the value is in use, however, the SET fails.
The network manager must re-read diffServCountActNextFree to obtain a
useful value.


3.4.3.  diffServDscpMarkActTable - The Mark Action Table

The Mark Action table is an unusual table, both in SNMP and in this MIB.
I might be viewed not so much as an array of single-object entries as an
array of OBJECT-IDENTIFIER conventions, as the OID for a
diffServDscpMarkActDscp instance conveys all of the necessary
information: packets are to be marked with the requisite DSCP.

As such, contrary to common practice, the index for the table is read-
only, and is both the Entry's index and its only value.


3.4.4.  diffServAlgDropTable - The Algorithmic Drop Table

The Algorithmic Drop Table identifies a dropping algorithm, drops
packets, and counts the drops.  Classified as an action, it is in effect
a method which applies a packet to a queue, and may modify either.  When
the algorithm is "always drop", this is simple; when the algorithm calls
for head-drop, tail-drop, or a variety of Active Queue Management, the
queue is inspected, and in the case of Active Queue Management,
additional parameters are required.

What may not be clear from the name is that an Algorithmic Drop action
often does not drop traffic.  Algorithms other than "always drop"
normally drop a few percent of packets at most.  The action inspects the
diffServQEntry that diffSeervAlgQMeasure points to in to determine
whether the packet should be dropped.

When the MIB is used for configuration, diffServAlgDropNextFree always
contains a legal value for diffServAlgDropId that is not currently used
in the system's configuration.  The Network Management Application reads
the variable and uses the value read in a create- and-go or a create-
and-wait SET.  When the SET is performed, the agent must determine
whether the value is indeed still unused; two network managers may
attempt to create a configuration entry simultaneously and use the same
value.  If it is currently unused, the SET succeeds and the agent
changes the value of diffServAlgDropNextFree according to an agent-
specific algorithm.  If the value is in use, however, the SET fails.
The network manager must re-read diffServAlgDropNextFree to obtain a
useful value.






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3.4.5.  diffServRandomDropTable - The Random Drop Parameters Table

The Random Drop Table is an extension of the Algorithmic Drop Table
intended for use on queues whose depth is actively managed.  Active
Queue Management algorithms are typified by [RED93], but the parameters
they use vary.  It was deemed for the purposes of this MIB that the
proper values to represent include:


 o      Target case mean queue depth, expressed in bytes or packets

 o      Worst case mean queue depth, expressed in bytes or packets

 o      Maximum drop rate expressed as drops per thousand

 o      Coefficient of an exponentially weighted moving average,
        expressed as the numerator of a fraction whose denominator is
        65536.

 o      Sampling rate

An example of the representation chosen in this MIB for this element is
shown in Figure 1.

Random droppers often have their drop probability function described as
a plot of drop probability (P) against averaged queue length (Q).
(Qmin,Pmin) then defines the start of the characteristic plot.  Normally
Pmin=0, meaning with average queue length below Qmin, there will be no
drops.  (Qmax,Pmax) defines a "knee" on the plot, after which point the
drop probability 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

      AlgDrop                                   Queue
      +-----------------+                       +-------+
  --->| Next   ---------+--+------------------->| Next -+--> ...
      | QMeasure -------+--+                    | ...   |
      | QThreshold      |     RandomDrop        +-------+
      | Type=randomDrop |     +----------------+
      | Specific -------+---->| MinThreshBytes |
      +-----------------+     | MaxThreshBytes |
                              | ProbMax        |
                              | Weight         |
                              | SamplingRate   |
                              +----------------+







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length, although it is possible for Qclip to equal Qmax.

In the MIB module, DiffServRandomDropMinThreshBytes and
DiffServRandomDropMinThreshPkts represent Qmin.
DiffServRandomDropMaxThreshBytes and DiffServRandomDropMaxThreshPkts
represent Qmax.  DiffServAlgDropQThreshold represents Qclip.
DiffServRandomDropInvProbMax represents Pmax (inverse).  This MIB does
not represent Pmin (assumed to be zero unless otherwise represented).
In addition, since message memory is finite, queues generally have some
upper bound above which they are incapable of storing additional
traffic.  Normally this number is equal to Qclip, specified by
diffServAlgDropQThreshold.

Each random dropper specification is associated with a queue.  This
allows multiple drop processes (of same or different types) to be
associated with the same queue, as different PHB implementations may
require.  This also allows for sequences of multiple droppers if
necessary.

The calculation of a smoothed queue length may also have an important
bearing on the behavior of the dropper: parameters may include the
sampling interval or rate, and the weight of each sample.  The
performance may be very sensitive to the values of these parameters and
a wide range of possible values may be required due to a wide range of
link speeds.  Most algorithms include a sample weight, represented here
by DiffServRandomDropInvWeight.  The availability of
DiffServRandomDropSamplingRate as readable is important, the information
provided by Sampling Rate is essential to the configuration of
DiffServRandomDropInvWeight.  Having Sampling Rate be configurable is
also helpful, as line speed increases, the ability to have queue
sampling be less frequent than packet arrival is needed.  Note, however,
that there is ongoing research on this topic, see e.g.  [ACTQMGMT] and
[AQMROUTER].

Additional parameters may be added in an enterprise MIB module, e.g.  by
using AUGMENTS on this table, to handle aspects of random drop
algorithms that are not standardized here.

When the MIB is used for configuration, diffServRandomDropNextFree
always contains a legal value for diffServRandomDropId that is not
currently used in the system's configuration.  The Network Management
Application reads the variable and uses the value read in a create-
and-go or a create-and-wait SET.  When the SET is performed, the agent
must determine whether the value is indeed still unused; two network
managers may attempt to create a configuration entry simultaneously and
use the same value.  If it is currently unused, the SET succeeds and the
agent changes the value of diffServRandomDropNextFree according to an





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agent-specific algorithm.  If the value is in use, however, the SET
fails.  The network manager must re-read diffServRandomDropNextFree to
obtain a useful value.


3.5.  Queuing and Scheduling of Packets

These include Queues and Schedulers, which are inter-related in their
use of queuing techniques.  By doing so, it is possible to build multi-
level schedulers, such as those which treat a set of queues as having
priority among them, and at a specific priority find a secondary WFQ
scheduler with some number of queues.


3.5.1.  diffServQTable - The Class or Queue Table

The Queue Table models simple FIFO queues.  The Scheduler Table allows
flexibility in constructing both simple and somewhat more complex
queuing hierarchies from those queues.

Queue Table entries are pointed at by the "next" attributes of the
upstream elements, such as DiffServMeterSucceedNext or
diffServActionNext.  Note that multiple upstream elements may direct
their traffic to the same Queue Table entry.  For example, the Assured
Forwarding PHB suggests that all traffic marked AF11, AF12 or AF13 be
placed in the same queue, after metering, without reordering.  To
accomplish that, the upstream diffServAlgDropNext pointers each point to
the same diffServQEntry.

A common requirement of a queue is that its traffic enjoy a certain
minimum or maximum rate, or that it be given a certain priority.
Functionally, the selection of such is a function of a scheduler, as in
Section .sh 4 "The parameter is associated with the queue, however,
using the Assured or Shaping Rate Parameters Table.

When the MIB is used for configuration, diffServQNextFree always
contains a legal value for diffServQId that is not currently used in the
system's configuration.  The Network Management Application reads the
variable and uses the value read in a create-and-go or a create- and-
wait SET.  When the SET is performed, the agent must determine whether
the value is indeed still unused; two network managers may attempt to
create a configuration entry simultaneously and use the same value.  If
it is currently unused, the SET succeeds and the agent changes the value
of diffServQNextFree according to an agent- specific algorithm.  If the
value is in use, however, the SET fails.  The network manager must re-
read diffServQNextFree to obtain a useful value.






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3.5.2.  diffServSchedulerTable - The Scheduler Table

The scheduler, and therefore the Scheduler Table, accepts inputs from
either queues or a preceding scheduler.  The Scheduler Table allows
flexibility in constructing both simple and somewhat more complex
queuing hierarchies from those queues.

When the MIB is used for configuration, diffServSchedulerNextFree always
contains a legal value for diffServSchedulerId that is not currently
used in the system's configuration.  The Network Management Application
reads the variable and uses the value read in a create- and-go or a
create-and-wait SET.  When the SET is performed, the agent must
determine whether the value is indeed still unused; two network managers
may attempt to create a configuration entry simultaneously and use the
same value.  If it is currently unused, the SET succeeds and the agent
changes the value of diffServSchedulerNextFree according to an agent-
specific algorithm.  If the value is in use, however, the SET fails.
The network manager must re-read diffServSchedulerNextFree to obtain a
useful value.


3.5.3.  diffServAssuredRateTable - The Assured Rate Table

When the output rate of a queue or scheduler must be given a minimum
rate or a priority, this is done using the diffServAssuredRateTable.
Rates may be expressed as absolute rates, or as a fraction of ifSpeed,
and imply the use of a rate-based scheduler such as WFQ or WRR.  The use
of a priority implies the use of a Priority Scheduler.  Only one of the
Absolute or Relative rate need be set; the other takes the relevant
value as a result.  Excess capacity is distributed proportionally among
the inputs to a scheduler.

The effect of combining priority and rate is to make the rates be in
fact fractions of ifSpeed less the actual amount of traffic passing,
although the fraction is calculated against the ifSpeed value.

When the MIB is used for configuration, diffServAssuredRateNextFree
always contains a legal value for diffServAssuredRateId that is not
currently used in the system's configuration.  The Network Management
Application reads the variable and uses the value read in a create-
and-go or a create-and-wait SET.  When the SET is performed, the agent
must determine whether the value is indeed still unused; two network
managers may attempt to create a configuration entry simultaneously and
use the same value.  If it is currently unused, the SET succeeds and the
agent changes the value of diffServAssuredRateNextFree according to an
agent-specific algorithm.  If the value is in use, however, the SET
fails.  The network manager must re-read diffServAssuredRateNextFree to





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obtain a useful value.


3.5.4.  diffServShapingRateTable - The Shaping Rate Table

When the output rate of a queue or scheduler must be limited to at most
a specified maximum rate, this is done using the
diffServShapingRateTable.  Rates may be expressed as absolute rates, or
as a fraction of ifSpeed.  Only one of the Absolute or Relative rate
need be set; the other takes the relevant value as a result.

The definition of a multirate shaper requires multiple
diffServShapingRateEntries.  In this case, an algorithm such as SHAPING
is used.  In that algorithm, more than one rate is specified, and at any
given time traffic is shaped to the lowest specified rate which exceeds
the arrival rate of traffic.

When the MIB is used for configuration, diffServShapingRateNextFree
always contains a legal value for diffServShapingRateId that is not
currently used in the system's configuration.  The Network Management
Application reads the variable and uses the value read in a create-
and-go or a create-and-wait SET.  When the SET is performed, the agent
must determine whether the value is indeed still unused; two network
managers may attempt to create a configuration entry simultaneously and
use the same value.  If it is currently unused, the SET succeeds and the
agent changes the value of diffServShapingRateNextFree according to an
agent-specific algorithm.  If the value is in use, however, the SET
fails.  The network manager must re-read diffServShapingRateNextFree to
obtain a useful value.


3.5.5.  Using queues and schedulers together

For representing a Strict Priority scheduler, each scheduler input is
assigned a priority with respect to all the other inputs feeding the
same scheduler, with default values for the other parameters.  Higher-
priority traffic that is not being delayed for shaping will be serviced
before a lower-priority input.  An example is found in Figure 2.

For Weighted Queuing methods, such as WFQ or WRR, the "weight" of a
given scheduler input is represented with a Minimum Service Rate leaky-
bucket profile which provides guaranteed minimum bandwidth to that
input, if required.  This is represented by a rate
DiffServAssuredRateAbs; the classical weight is the ratio between that
rate and the interface speed, or perhaps the ratio between that rate and
the sum of the configured rates for classes.  The rate may be
represented by a relative value, as a fraction of the interface's





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                      +-----+
+-------+             | P S |
| Queue +------------>+ r c |
+-------+-+--------+  | i h |
          |Priority|  | o e |
          +--------+  | r d +----------->
+-------+             | i u |
| Queue +------------>+ t l |
+-------+-+--------+  | y e |
          |Priority|  |   r |
          +--------+  +-----+


current line rate.  DiffServAssuredRateRel to assist in cases where line
rates are variable or where a higher-level policy might be expressed in
terms of fractions of network resources.  The two rate parameters are
inter-related and changes in one may be reflected in the other.  An
example is found in figure 4.

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


                      +-----+
+-------+             | W S |
| Queue +------------>+ R c |
+-------+-+--------+  | R h |
          |  Rate  |  |   e |
          +--------+  | o d +----------->
+-------+             | r u |
| Queue +------------>+   l |
+-------+-+--------+  | W e |
          |  Rate  |  | F r |
          +--------+  | Q   |
                      +-----+








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profile in order to limit the scheduler bandwidth available to that
input.  This is represented by a rate, in DiffServShapingRateAbs; the
classical weight is the ratio between that rate and the interface speed,
or perhaps the ratio between that rate and the sum of the configured
rates for classes.  The rate may be represented by a relative value, as
a fraction of the interface's current line rate, DiffServShapingRateRel.
There was discussion in the working group about alternative modeling
approaches, such as defining a shaping action or a shaping element.
This MIB does 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
the authors felt it was simpler and more elegant to simply describe it
in that context.

The same may be done on a queue, if a given class is to be shaped to a
maximum rate without shaping other classes, as in Figure 5.

Other types of priority and weighted scheduling methods can be defined
using existing parameters in DiffServAssuredRateEntry.  NOTE:
DiffServSchedulerMethod uses OBJECT IDENTIFIER syntax, with the
different types of scheduling methods defined as OBJECT-IDENTITY.
Future scheduling methods may be defined in other MIBs.  This requires
an OBJECT-IDENTITY definition, a description of how the existing objects
are reused, if they are, and any new objects they require.

Queue Table entries are pointed at by the "next" attributes of the
upstream elements, such as DiffServMeterSucceedNext or
diffServActionNext.  Note that multiple upstream elements may direct
their traffic to the same Queue Table entry.  For example, the Assured
Forwarding PHB suggests that all traffic marked AF11, AF12 or AF13 be


                      +---+
+-------+             | S |
| Queue +------------>+ c |
+-------+-+--------+  | h |
          |        |  | e +----------->
          +--------+  | d +-+-------+
                      | u | |Maximum|
+-------+             | l | | Rate  |
| Queue +------------>+ e | +-------+
+-------+-+--------+  | r |
          |        |  |---+
          +--------+








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                      +---+
+-------+             | S |
| Queue +------------>+ c |
+-------+-+--------+  | h |
          |Min Rate|  | e +----------->
          +--------+  | d |
                      | u |
+-------+             | l |
| Queue +------------>+ e |
+-------+-+--------+  | r |
          |Min Rate|  |   |
          +--------+  |   |
          |Max Rate|  |   |
          +--------+  +---+

placed in the same queue, after metering, without reordering.  To
accomplish that, the upstream diffServAlgDropNext pointers each point to
the same diffServQEntry.

A common requirement of a queue is that its traffic enjoy a certain
minimum or maximum rate, or that it be given a certain priority.
Functionally, the selection of such is a function of a scheduler, as in
Section .sh 4 "The parameter is associated with the queue, however,
using the Assured or Shaping Rate Parameters Table.

To implement an EF and two AF classes, one must use a combination of
priority and WRR/WFQ scheduling.  This requires us to cascade two
schedulers.  If we were to additionally shape the output of the system
to a rate lower than the interface rate, we must place an upper bound
rate on the output of the priority scheduler.  See figure 4.

3.6.  Example configuration for AF and EF

For the sake of argument, let us build an example with one EF class and
four AF classes using the constructs in this MIB.


3.6.1.  AF and EF Ingress Interface Configuration

The ingress edge interface identifies traffic into classes, meters it,
and ensures that any excess is appropriately dealth with according to
the PHB.  For AF, this means marking excess; for EF, it means dropping
excess or shaping it to a maximum rate.








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                                            +-----+
+-------+                                   | P S |
| Queue +---------------------------------->+ r c |
+-------+----------------------+--------+   | i h |
                               |Priority|   | o e +----------->
                               +--------+   | r d +-+-------+
                      +------+              | i u | |Maximum|
+-------+             | W S  +------------->+ t l | | Rate  |
| Queue +------------>+ R c  +-+--------+   | y e | +-------+
+-------+-+--------+  | R h  | |Priority|   |   r |
          |Min Rate|  |   e  | +--------+   +-----+
          +--------+  | o d  |
+-------+             | r u  |
| Queue +------------>+   l  |
+-------+-+--------+  | W e  |
          |Min Rate|  | F r  |
          +--------+  | Q    |
                      +------+
































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  +-----------------------+
  | diffServDataPathStart |
  +-----------+-----------+
              |
   +----------+
   |
+--+--+     +-----+     +-----+     +-----+     +-----+
| AF1 +-----+ AF2 +-----+ AF3 +-----+ AF4 +-----+ EF  |
+--+--+     +--+--+     +--+--+     +--+--+     +--+--+
   |           |           |           |           |
+--+--+     +--+--+     +--+--+     +--+--+     +--+--+
|TRTCM|     |TRTCM|     |TRTCM|     |TRTCM|     |srTCM|
|Meter|     |Meter|     |Meter|     |Meter|     |Meter|
|-+++-|     |-+++-|     |-+++-|     |-+++-|     +-+-+-+
  |||         |||         |||         |||         | |
+-+||---+   +-+||---+   +-+||---+   +-+||---+   +-+-|---+
|+-+|----+  |+-+|----+  |+-+|----+  |+-+|----+  |+--+----+
||+-+-----+ ||+-+-----+ ||+-+-----+ ||+-+-----+ ||Actions|
+||Actions| +||Actions| +||Actions| +||Actions| +|Below  |
 +|Below  |  +|Below  |  +|Below  |  +|Below  |  +-+-----+
  +-+-----+   +-+-----+   +-+-----+   +-+-----+    |
  |||         |||         |||         |||          |
  VVV         VVV         VVV         VVV          V

        Accepted traffic is sent to IP forwarding

3.6.1.1.  Classification In The Example

A packet arriving at an ingress interface picks up its "program" from
the diffServDataPathTable.  This points to a classifier, which will
select traffic according to some specification for each traffic class.

An example of a classifier for an AFm class would be a succession of
three classifier elements, each pointing to a Six-tuple classification
parameter block identifying one of the AFmn DSCPs.  Alternatively, the
six-tuples might contain selectors for HTTP traffic or some other
application.

An example of a classifier for EF traffic might be either a classifier
element pointing to a six-tuple parameter specifying the EF code point,
or a collection of classifiers with parameter blocks specifying
individual telephone calls, or a variety of other approaches.

Each classifier hands its traffic off to appropriate functional data
path elements.







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3.6.1.2.  AF Implementation On an Ingress Edge Interface

Each Afm class applies a Two Rate Three Color Meter, dividing traffic
into three groups.  These groups of traffic conform to both specified
rates, only the higher one, or none.  The intent, on the ingress
interface at the edge of the network, is to measure and appropriately
mark traffic.


3.6.1.2.1.  AF Metering On an Ingress Edge Interface

Each Afm class applies a Two Rate Three Color Meter, dividing traffic
into three groups.  If two rates R and S, with R < S, are specified and
traffic arrives at rate T, traffic comprising up to R bits per second is
considered to conform to the "confirmed" rate, R.  If R < T, traffic
comprising up to S-R bits per second is considered to conform to the
"excess" rate, S.  Any further excess is non- conformant.

To configure this, we apply two Meter Entries, one for the conforming
rate and one for the excess rate.  The rate parameters are stored in
associated Token Bucket Parameter Entries.  The "FailNext" pointer of
the lower rate Meter Entry points to the other Meter Entry; both
"SucceedNext" pointers and the "FailNext" pointer of the higher Meter
Entry point to lists of actions.  In the color-blind mode, all three
classifier "next" entries point to the lower rate meter entry.  In the
color-aware mode, the AFm1 classifier points to the lower rate entry,
the AFm2 classifier points to the higher rate entry (as it is only
compared against that rate), and the AFm3 classifier points directly to
the actions taken when both rates fail.


3.6.1.2.2.  AF Actions On an Ingress Edge Interface

For network planning and perhaps for billing purposes, arriving traffic
is normally counted.  Therefore, a "count" action, consisting of an
action table entry pointing to a count table entry, is configured.

Also, traffic is marked with the appropriate DSCP.  The first R bits per
second are marked AFm1, the next S-R bits per second are marked AFm2,
and the rest is marked AFm3.  It may be that traffic is arriving marked
with the same DSCP, but in general, the additional complexity of
deciding that it is being remarked to the same value is not useful.
Therefore, a "mark" action, consisting of an action table entry pointing
to a mark table entry, is configured.

At this point, the usual case is that traffic is now forwarded in the
usual manner.  To indicate this, we set the "SucceedNext" pointer of the





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Mark Action is left at zeroDotZero.


3.6.1.3.  EF Implementation On an Ingress Edge Interface

The EF class applies a Single Rate Two Color Meter, dividing traffic
into "conforming" and "excess" groups.  The intent, on the ingress
interface at the edge of the network, is to measure and appropriately
mark conforming traffic and drop the excess.


3.6.1.3.1.  EF Metering On an Ingress Edge Interface

A single rate two color (SRTCM) meter requires one token bucket.  It is
therefore configured using a single meter entry with a corresponding
Token Bucket Parameter Entry.  Arriving traffic either "succeeds" or
"fails".


3.6.1.3.2.  EF Actions On an Ingress Edge Interface

For network planning and perhaps for billing purposes, arriving traffic
that conforms to the meter is normally counted.  Therefore, a "count"
action, consisting of an action table entry pointing to a count table
entry, is configured.

Also, traffic is (re)marked with the EF DSCP.  Therefore, a "mark"
action, consisting of an action table entry pointing to a mark table
entry, is configured.

At this point, the successful traffic is now forwarded in the usual
manner.  To indicate this, we set the "SucceedNext" pointer of the Mark
Action is left at zeroDotZero.

Traffic that exceeded the arrival policy, however, is to be dropped.  We
can use a count action on this traffic if the several counters are
interesting.  However, since the drop counter in the Algorithmic Drop
Entry will count packets dropped, this is not clearly necessary.  We
configure an Alorithmic Drop Entry of the type "alwaysDrop," with no
successor.

3.7.  AF and EF Egress Edge Interface Configuration

3.7.1.  Classification On an Egress Edge Interface

A packet arriving at an egress interface may have been classified on an
ingress interface, and the egress interface may have access to that





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  +-----------------------+
  | diffServDataPathStart |
  +-----------+-----------+
              |
   +----------+
   |
+--+--+     +-----+     +-----+     +-----+     +-----+
| AF1 +-----+ AF2 +-----+ AF3 +-----+ AF4 +-----+ EF  |
|-+++-|     |-+++-|     |-+++-|     |-+++-|     +-+-+-+
  |||         |||         |||         |||         | |
|-+++-|     |-+++-|     |-+++-|     |-+++-|     +-+-+-+
|TRTCM|     |TRTCM|     |TRTCM|     |TRTCM|     |srTCM|
|Meter|     |Meter|     |Meter|     |Meter|     |Meter|
|-+++-|     |-+++-|     |-+++-|     |-+++-|     +-+-+-+
  |||         |||         |||         |||         | |
+-+||---+   +-+||---+   +-+||---+   +-+||---+   +-+-|---+
|+-+|----+  |+-+|----+  |+-+|----+  |+-+|----+  |+--+----+
||+-+-----+ ||+-+-----+ ||+-+-----+ ||+-+-----+ ||Actions|
+||Actions| +||Actions| +||Actions| +||Actions| +|Below  |
 +|Below  |  +|Below  |  +|Below  |  +|Below  |  +-+-----+
  +-+-----+   +-+-----+   +-+-----+   +-+-----+    |
  |||         |||         |||         |||          |
+-+++--+    +-+++--+    +-+++--+    +-+++--+    +--+---+
| Queue|    | Queue|    | Queue|    | Queue|    | Queue|
+--+---+    +--+---+    +--+---+    +--+---+    +--+---+
   |           |           |           |           |
+--+-----------+-----------+-----------+---+       |
|     WFQ/WRR Scheduler                    |       |
+--------------------------------------+---+       |
                                       |           |
                                 +-----+-----------+----+
                                 |  Priority Scheduler  |
                                 +----------+-----------+
                                            |
                                            V


information.  If it is relevant, there is no reason not to use that
information.  If it is not available, however, there may be a need to
(re)classify on the egress interface.  In any event, it picks up its
"program" from the diffServDataPathTable.  This points to a classifier,
which will select traffic according to some specification for each
traffic class.

An example of a classifier for an AFm class would be a succession of





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three classifier elements, each pointing to a Six-tuple classification
parameter block identifying one of the AFmn DSCPs.  Alternatively, the
six-tuples might contain selectors for HTTP traffic or some other
application.

An example of a classifier for EF traffic might be either a classifier
element pointing to a six-tuple parameter specifying the EF code point,
or a collection of classifiers with parameter blocks specifying
individual telephone calls, or a variety of other approaches.

Each classifier hands its traffic off to appropriate functional data
path elements.


3.7.2.  AF Implementation On an Egress Edge Interface

Each Afm class applies a Two Rate Three Color Meter, dividing traffic
into three groups.  These groups of traffic conform to both specified
rates, only the higher one, or none.  The intent, on the ingress
interface at the edge of the network, is to measure and appropriately
mark traffic.


3.7.2.1.  AF Metering On an Egress Edge Interface

Each Afm class applies a Two Rate Three Color Meter, dividing traffic
into three groups.  If two rates R and S, with R < S, are specified and
traffic arrives at rate T, traffic comprising up to R bits per second is
considered to conform to the "confirmed" rate, R.  If R < T, traffic
comprising up to S-R bits per second is considered to conform to the
"excess" rate, S.  Any further excess is non- conformant.

To configure this, we apply two Meter Entries, one for the conforming
rate and one for the excess rate.  The rate parameters are stored in
associated Token Bucket Parameter Entries.  The "FailNext" pointer of
the lower rate Meter Entry points to the other Meter Entry; both
"SucceedNext" pointers and the "FailNext" pointer of the higher Meter
Entry point to lists of actions.  In the color-blind mode, all three
classifier "next" entries point to the lower rate meter entry.  In the
color-aware mode, the AFm1 classifier points to the lower rate entry,
the AFm2 classifier points to the higher rate entry (as it is only
compared against that rate), and the AFm3 classifier points directly to
the actions taken when both rates fail.









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3.7.2.2.  AF Actions On an Egress Edge Interface

For network planning and perhaps for billing purposes, departing traffic
is normally counted.  Therefore, a "count" action, consisting of an
action table entry pointing to a count table entry, is configured.

Also, traffic may be marked with an appropriate DSCP.  The first R bits
per second are marked AFm1, the next S-R bits per second are marked
AFm2, and the rest is marked AFm3.  It may be that traffic is arriving
marked with the same DSCP, but in general, the additional complexity of
deciding that it is being remarked to the same value is not useful.
Therefore, a "mark" action, consisting of an action table entry pointing
to a mark table entry, is configured.

At this point, the usual case is that traffic is now queued for
transmission.  The queue uses Active Queue Management, using an
algorithm such as RED.  Therefore, an Algorithmic Dropper is configured
for each AFmn traffic stream, with a slightly lower min- threshold (and
possibly lower max-threshold) for the excess traffic than for the
committed traffic.


3.7.2.3.  AF Rate-based Queuing On an Egress Edge Interface

The queue expected by AF is normally a work-conserving queue.  It
usually has a specified minimum rate, and may have a maximum rate below
the bandwidth of the interface.  In concept, it will use as much
bandwidth as is available to it, but assure the lower bound.

Common ways to implement this include various forms of Weighted Fair
Queuing (WFQ) or Weighted Round Robin (WRR).  Integrated over a longer
interval, these give each class a predictable throughput rate.  They
differ in that over short intervals they will order traffic differently.
In general, traffic classes that keep traffic in queue will tend to
absorb latency from queues with lower mean occupancy, in exchange for
which they make use of any available capacity.


3.7.3.  EF Implementation On an Egress Edge Interface

The EF class applies a Single Rate Two Color Meter, dividing traffic
into "conforming" and "excess" groups.  The intent, on the egress
interface at the edge of the network, is to measure and appropriately
mark conforming traffic and drop the excess.








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3.7.3.1.  EF Metering On an Egress Edge Interface

A single rate two color (SRTCM) meter requires one token bucket.  It is
therefore configured using a single meter entry with a corresponding
Token Bucket Parameter Entry.  Arriving traffic either "succeeds" or
"fails".


3.7.3.2.  EF Actions On an Egress Edge Interface

For network planning and perhaps for billing purposes, departing traffic
that conforms to the meter is normally counted.  Therefore, a "count"
action, consisting of an action table entry pointing to a count table
entry, is configured.

Also, traffic is (re)marked with the EF DSCP.  Therefore, a "mark"
action, consisting of an action table entry pointing to a mark table
entry, is configured.

At this point, the successful traffic is now queued for transmission,
using a priority queue or perhaps a rate-based queue with significant
over-provision.  Since the amount of traffic present is known, one might
not drop from this queue at all.

Traffic that exceeded the policy, however, is dropped.  We can use a
count action on this traffic if the several counters are interesting.
However, since the drop counter in the Algorithmic Drop Entry will count
packets dropped, this is not clearly necessary.  We configure an
Alorithmic Drop Entry of the type "alwaysDrop," with no successor.


3.7.3.3.  EF Priority Queuing On an Egress Edge Interface

The normal implementation is a priority queue, to minimize induced
jitter.  By this, we mean that a separate queue is used for each EF
class, with a strict ordering.

4.  Conventions used in this MIB

4.1.  The use of RowPointer to indicate data path linkage

RowPointer is a textual convention used to identify a conceptual row in
an SNMP Table by pointing to one of its objects. One of the ways it this
MIB uses it is to indicate succession, pointing to data path linkage
table entries.







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For succession, it answers the question "what happens next?". Rather
than presume that the next table must be as specified in the conceptual
model [MODEL] and providing its index, the RowPointer takes you to the
MIB row representing that thing. In the DiffServMeterTable, for example,
the DiffServMeterFailNext RowPointer might take you to another meter,
while the DiffServMeterSucceedNext RowPointer would take you to an
action.

Since a RowPointer is not tied to any specific object except by the
value it contains, it is possible and acceptable to use RowPointers to
merge data paths.  An obvious example of such a use is in the
classifier: traffic matching the DSCPs AF11, AF12, and AF13 might be
presented to the same meter in order to perform the processing described
in the Assured Forwarding PHB. Another use would be to merge data paths
from several interfaces; if they represent a single service contract,
having them share a common set of counters and common policy may be a
desireable configuration. Note well, however, that suchconfigurations
may have related implementation issues - if Differentiated Services
processing for the interfaces is implemented in multiple forwarding
engines, the engines will need to communicate if they are to implement
such a feature. An implementation that fails to provide this capability
is not considered to have failed the intention of this MIB or of the
[MODEL]; an implementation that does provide it is not considered
superior from a standards perspective.

     NOTE -- the RowPointer construct is used to connect the functional
     data paths.  The [MODEL] describes these as TCBs, as an aid to
     understanding. This MIB, however, does not model TCBs directly. It
     operates at a lower level of abstraction using only individual
     elements, connected in succession by RowPointers. Therefore, the
     concept of TCBs enclosing individual Functional Data Path elements
     is not directly applicable to this MIB, although management tools
     that use this MIB may employ such a concept.

It is possible that a path through a device following a set of
RowPointers is indeterminate i.e. it ends in a dangling RowPointer.
Guidance is provided in the MIB module's DESCRIPTION-clause for each of
the linkage attribute.  In general, for both zeroDotZero and dangling
RowPointer, it is assumed the data path ends and the traffic should be
given to the next logical part of the device, usually a forwarding
process or a transmission engine, or the proverbial bit-bucket. Any
variation from this usage is indicated by the attribute affected.

4.2.  The use of RowPointer to indicate parameters

RowPointer is also used in this MIB to indicate parameterization, for
pointing to parameterization table entries.





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For indirection (as in the DiffServClfrElementTable), the idea is to
allow other MIBs, including proprietary ones, to define new and arcane
filters - MAC headers, IPv4 and IPv6 headers, BGP Communities and all
sorts of other things - whilst still utilizing the structures of this
MIB. This is a form of class inheritance (in "object oriented"
language): it allows base object definitions ("classes") to be extended
in proprietary or standard ways, in the future, by other documents.

RowPointer also clearly indicates the identified conceptual row's
content does not change, hence they can be simultaneously used, pointed
to, by more than one data path linkage table entries.  The
identification of RowPointer allows higher level policy mechanisms to
take advantage of this characteristic.


4.3.  Conceptual row creation and deletion

A number of conceptual tables defined in this MIB use as an index an
arbitrary integer value, unique across the scope of the agent. In order
to help with multi-manager row-creation problems, a mechanism must be
provided to allow a manager to obtain unique values for such an index
and to ensure that, when used, the manager knows whether it got what it
wanted or not.

Typically, such a table has an associated NextFree variable e.g.
DiffServClfrNextFree which provides a suitable value for the index of
the next row to be created e.g. DiffServClfrElementClfrId. The value
zero is used to indicate that the agent can configure no more entries.
The table also has a columnar Status attribute with RowStatus syntax
[6].

Generally, if a manager attempts to create a row, using either
createAndGo or createAndWait, the agent will create the row and return
success. If the agent has insufficient resources or such a row already
exists, then it returns an error. A manager must be prepared to try
again in such circumstances, probably by re-reading the NextFree to
obtain a new index value in case a second manager had got in between the
first manager's read of the NextFree value and the first manager's row-
creation attempt. The use of RowStatus is covered in more detail in [6].


5.  Extending this MIB

With the structures of this MIB divided into data path linkage tables
and parameterization tables, and with the use of RowPointer, new data
path linkage and parameterization tables can be defined in other MIB
modules, and used with tables defined in this MIB.  This MIB does not





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limit on the type of entries its RowPointer attributes can point to,
hence new functional data path elements can be defined in other MIBs and
integrated with functional data path elements of this MIB.  For example,
new Action functional data path element can be defined for Traffic
Engineering and be integrated with Differentiated Services functional
data path elements, possibly used within the same data path sharing the
same classifiers and meters.

It is more likely that new parameterization tables will be created in
other MIBs as new methods or proprietary methods get deployed for
existing Differentiated Services functional data path elements.  For
example, different kinds of filters can be defined by using new filter
parameterization tables.  New scheduling methods can be deployed by
defining new scheduling method OIDs and new scheduling parameter tables.

Notice both new data path linkage tables and parameterization tables can
be added without needing to change this MIB document or affect existing
tables and their usage.


































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6.  MIB Definition


DIFFSERV-DSCP-TC DEFINITIONS ::= BEGIN

    IMPORTS
    Integer32, MODULE-IDENTITY, mib-2
         FROM SNMPv2-SMI
    TEXTUAL-CONVENTION
         FROM SNMPv2-TC;

diffServDSCPTC MODULE-IDENTITY
    LAST-UPDATED "0101080000Z"
    ORGANIZATION "IETF Differentiated Services WG"
    CONTACT-INFO
       "       Fred Baker
               Cisco Systems
               519 Lado Drive
               Santa Barbara, CA 93111, USA
               E-mail: fred@cisco.com

               Kwok Ho Chan
               Nortel Networks
               600 Technology Park Drive
               Billerica, MA 01821, USA
               E-mail: khchan@nortelnetworks.com

               Andrew Smith
               Allegro Networks
               6399 San Ignacio Ave
               San Jose, CA 95119, USA
               E-mail: andrew@allegronetworks.com

                 Differentiated Services Working Group:
                 diffserv@ietf.org"
    DESCRIPTION
       "The Textual Conventions defined in this module should be used
       whenever a Differentiated Services Code Point is used in a MIB."
    REVISION "0106030000Z"
    DESCRIPTION
       "Initial version, published as RFC xxxx."
    ::= { mib-2 12344 }  -- to be assigned by IANA

Dscp ::= TEXTUAL-CONVENTION
    DISPLAY-HINT "d"
    STATUS   current
    DESCRIPTION





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       "A Differentiated Services Code-Point that may be used for
       marking a traffic stream."
    REFERENCE
        "RFC 2474, RFC 2780"
    SYNTAX   Integer32 (0..63)

DscpOrAny ::= TEXTUAL-CONVENTION
    DISPLAY-HINT "d"
    STATUS   current
    DESCRIPTION
       "The IP header Differentiated Services Code-Point that may be
       used for discriminating among traffic streams. The value -1 is
       used to indicate a wild card i.e. any value."
    REFERENCE
        "RFC 2474, RFC 2780"
    SYNTAX   Integer32 (-1 | 0..63)
END



































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DIFFSERV-MIB DEFINITIONS ::= BEGIN

    IMPORTS
    Unsigned32, Counter32, Counter64,
    MODULE-IDENTITY, OBJECT-TYPE, OBJECT-IDENTITY,
    zeroDotZero, mib-2
         FROM SNMPv2-SMI
    TEXTUAL-CONVENTION, RowStatus, RowPointer, TimeStamp
         FROM SNMPv2-TC
    MODULE-COMPLIANCE, OBJECT-GROUP
         FROM SNMPv2-CONF
    ifIndex
        FROM IF-MIB
    InetAddressType, InetAddress, InetAddressPrefixLength,
    InetPortNumber
        FROM INET-ADDRESS-MIB
    BurstSize
        FROM INTEGRATED-SERVICES-MIB
    Dscp, DscpOrAny
        FROM DIFFSERV-DSCP-TC;

diffServMib MODULE-IDENTITY
    LAST-UPDATED "0102210000Z"
    ORGANIZATION "IETF Differentiated Services WG"
    CONTACT-INFO
       "       Fred Baker
               Cisco Systems
               519 Lado Drive
               Santa Barbara, CA 93111, USA
               E-mail: fred@cisco.com

               Kwok Ho Chan
               Nortel Networks
               600 Technology Park Drive
               Billerica, MA 01821, USA
               E-mail: khchan@nortelnetworks.com

               Andrew Smith
               Allegro Networks
               6399 San Ignacio Ave
               San Jose, CA 95119, USA
               E-mail: andrew@allegronetworks.com

               Differentiated Services Working Group:
               diffserv@ietf.org"
    DESCRIPTION
       "This MIB defines the objects necessary to manage a device that





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       uses the Differentiated Services Architecture described in RFC
       2475. The Conceptual Model of a Differentiated Services Router
       provides supporting information on how such a router is modeled."
    REVISION "0106030000Z"
    DESCRIPTION
       "Initial version, published as RFC xxxx."
    ::= { mib-2 1 }

diffServMIBObjects     OBJECT IDENTIFIER ::= { diffServMib 1 }
diffServMIBConformance OBJECT IDENTIFIER ::= { diffServMib 2 }

-- These textual conventions have no effect on either the syntax
-- or the semantics of any managed object.  Objects defined using
-- this convention are always encoded by means of the rules that
-- define their primitive type.

IfDirection ::= TEXTUAL-CONVENTION
    STATUS current
    DESCRIPTION
       "IfDirection specifies a direction of data travel on an
       interface. 'inbound' traffic is operated on during reception from
       the interface, while 'outbound' traffic is operated on prior to
       transmission on the interface."
    SYNTAX  INTEGER {
                inbound(1),     -- ingress interface
                outbound(2)     -- egress interface
}

























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--
-- Data Path
--

diffServDataPath       OBJECT IDENTIFIER ::= { diffServMIBObjects 1 }

--
-- Data Path Table
--
-- The Data Path Table enumerates the Differentiated Services
-- Functional Data Paths within this device.  Each entry in this
-- table is indexed by ifIndex and ifDirection.  Each entry provides
-- the first Differentiated Services Functional Data Path Element to
-- process data flowing along specific data path.  This table should
-- have at most two entries for each interface capable of Differentiated
-- Services processing on this device: ingress and egress.

-- Note that Differentiated Services Functional Data Path Elements
-- linked together using their individual next pointers and anchored
-- by an entry of the diffServDataPathTable constitute a functional data
-- path.
--

diffServDataPathTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServDataPathEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The data path table contains RowPointers indicating the start of
       the functional data path for each interface and traffic direction
       in this device. These may merge, or be separated into parallel
       data paths by meters or classifiers."
    ::= { diffServDataPath 1 }

diffServDataPathEntry OBJECT-TYPE
    SYNTAX       DiffServDataPathEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the data path table indicates the start of a single
       Differentiated Services Functional Data Path in this device."
    INDEX { ifIndex, diffServDataPathIfDirection }
    ::= { diffServDataPathTable 1 }

DiffServDataPathEntry ::= SEQUENCE  {
    diffServDataPathIfDirection    IfDirection,
    diffServDataPathStart          RowPointer,





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    diffServDataPathStatus         RowStatus
}

diffServDataPathIfDirection OBJECT-TYPE
    SYNTAX       IfDirection
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "IfDirection specifies whether the reception or transmission path
       for this interface is in view."
    ::= { diffServDataPathEntry 1 }

diffServDataPathStart OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This selects the first Differentiated Services Functional Data
       Path element to handle traffic for this data path. This
       RowPointer should point to an instance of one of:
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServAlgDropEntry
         diffServQEntry

       A value of zeroDotZero in this attribute indicates that no
       Differentiated Services treatment is performed on traffic of this
       data path. A pointer with the value zeroDotZero normally
       terminates a functional data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    ::= { diffServDataPathEntry 2 }

diffServDataPathStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a row/entry. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServDataPathEntry 3 }








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--
-- Classifiers
--

diffServClassifier     OBJECT IDENTIFIER ::= { diffServMIBObjects 2 }

--
-- Classifier Table
--
--The Classifier Table allows multiple classifier elements, of same
--or different types, to be used together. A classifier must completely
--classify all packets presented to it. This means that all traffic
--presented to a classifier must match at least one classifier element
--within the classifier, with the classifier element parameters
--specified by a filter.
--
--If there is ambiguity between classifier elements of different
--classifier, classifier linkage order indicates their precedence;
--the first classifier in the link is applied to the traffic first.
--
--Entries in the classifier element table serves as the anchor for
--each classification pattern, defined in filter table entries.
--Each classifier element table entry also specifies the subsequent
--downstream Differentiated Services Functional Data Path element
--when the classification pattern is satisfied. Each entry in the
--classifier element table describes one branch of the fan-out
--characteristic of a classifier indicated in [MODEL] section 4.1.
--A classifier is composed of one or more classifier elements.

diffServClfrNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServClfrId instance. If a configuring system attempts
       to create a new row in the diffServClfrTable using this value,
       but an instance has been created or is in the process of being
       created, that operation will fail."
    ::= { diffServClassifier 1 }

diffServClfrTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServClfrEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "This table enumerates all the diffserv classifier functional





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       data path elements of this device.  The actual classification
       definitions are defined in diffServClfrElementTable entries
       belonging to each classifier."
    REFERENCE
        "[MODEL] section 4.1"
    ::= { diffServClassifier 2 }

diffServClfrEntry OBJECT-TYPE
    SYNTAX       DiffServClfrEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the classifier table describes a single classifier.
       All classifier elements belonging to the same classifier uses the
       classifier's diffServClfrId in their diffServClfrElementClfrId
       attribute."
    INDEX { diffServClfrId }
    ::= { diffServClfrTable 1 }

DiffServClfrEntry ::= SEQUENCE  {
    diffServClfrId              Unsigned32,
    diffServClfrDataPathStart   RowPointer,
    diffServClfrStatus          RowStatus
}

diffServClfrId OBJECT-TYPE
    SYNTAX       Unsigned32
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the classifier entries. The set of such
       identifiers spans the whole agent. Managers should obtain new
       values for row creation in this table by reading
       diffServClfrNextFree."
    ::= { diffServClfrEntry 1 }

diffServClfrDataPathStart OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This selects the first Differentiated Services Functional Data
       Path element to handle traffic for this classifier. This
       RowPointer should point to an instance of a
       diffServClfrElementEntry. It is primarily useful in indicating
       the first classifier element in a classifier other than the one
       pointed to by diffServClfrDataPathStart, although it may be used





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       for those classifiers as well.

       A value of zeroDotZero in this attribute indicates that no
       Differentiated Services treatment is performed on traffic of this
       data path. A pointer with the value zeroDotZero normally
       terminates a functional data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    ::= { diffServClfrEntry 2 }

diffServClfrStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a classifier. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServClfrEntry 3 }
































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-- Classifier Element Table
--
diffServClfrElementNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServClfrElementId instance. If a configuring system
       attempts to create a new row in the diffServClfrElementTable
       using this value, but an instance has been created or is in the
       process of being created, that operation will fail."
    ::= { diffServClassifier 3 }

diffServClfrElementTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServClfrElementEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The classifier element table enumerates the relationship between
       classification patterns and subsequent downstream Differentiated
       Services Functional Data Path elements.
       diffServClfrElementSpecific points to a filter that specifies the
       classification parameters. A classifier may use filter tables of
       different types together.

       One example of a filter table defined in this MIB is
       diffServSixTupleClfrTable, for IP Multi-Field Classifiers (MFCs).
       Such an entry might identify anything from a single micro-flow
       (an identifiable sub-session packet stream directed from one
       sending transport to the receiving transport or transports), or
       aggregates of those such as the traffic from a host, traffic for
       an application, or traffic between two hosts using an application
       and a given DSCP. The standard Behavior Aggregate used in the
       Differentiated Services Architecture is encoded as a degenerate
       case of such an aggregate - the traffic using a particular DSCP
       value.

       Filter tables for other filter types may be defined elsewhere."
    REFERENCE
        "[MODEL] section 4.1"
    ::= { diffServClassifier 4 }

diffServClfrElementEntry OBJECT-TYPE
    SYNTAX       DiffServClfrElementEntry
    MAX-ACCESS   not-accessible
    STATUS       current





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    DESCRIPTION
       "An entry in the classifier element table describes a single
       element of the classifier."
    INDEX { diffServClfrElementClfrId, diffServClfrElementId }
    ::= { diffServClfrElementTable 1 }

DiffServClfrElementEntry ::= SEQUENCE  {
    diffServClfrElementClfrId      INTEGER,
    diffServClfrElementId          INTEGER,
    diffServClfrElementPrecedence  Unsigned32,
    diffServClfrElementNext        RowPointer,
    diffServClfrElementSpecific    RowPointer,
    diffServClfrElementStatus      RowStatus
}

diffServClfrElementClfrId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the classifier entries. The set of such
       identifiers spans the whole agent. Managers obtain new values for
       row creation in this table by reading diffServClfrNextFree.

       A classifier Id identifies which classifier this classifier
       element is a part of."
    ::= { diffServClfrElementEntry 1 }

diffServClfrElementId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Classifier Element entries. The set
       of such identifiers spans the whole agent. Managers obtain new
       values for row creation in this table by reading
       diffServClfrElementNextFree."
    ::= { diffServClfrElementEntry 2 }

diffServClfrElementPrecedence OBJECT-TYPE
    SYNTAX       Unsigned32
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The relative order in which classifier elements are applied:
       higher numbers represent classifier element with higher
       precedence.  Classifier elements with the same order must be





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       unambiguous i.e. they must define non-overlapping patterns, and
       are considered to be applied simultaneously to the traffic
       stream. Classifier elements with different order may overlap in
       their filters:  the classifier element with the highest order
       that matches is taken.

       On a given interface, there must be a complete classifier in
       place at all times in the ingress direction.  This means one or
       more filters must match any possible pattern. There is no such
       requirement in the egress direction."
    DEFVAL { 0 }
    ::= { diffServClfrElementEntry 3 }

diffServClfrElementNext OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This attribute provides one branch of the fan-out functionality
       of a classifier described in [MODEL] section 4.1.

       This selects the next Differentiated Services Functional Data
       Path element to handle traffic for this data path. This
       RowPointer should point to an instance of one of:
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServAlgDropEntry
         diffServQEntry

       A value of zeroDotZero in this attribute indicates no further
       Differentiated Services treatment is performed on traffic of this
       data path. The use of zeroDotZero is the normal usage for the
       last functional data path element of the current data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."

    ::= { diffServClfrElementEntry 4 }

diffServClfrElementSpecific OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "A pointer to a valid entry in another table, filter table, that
       describes the applicable classification parameters, e.g. an entry





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       in diffServSixTupleClfrTable.

       If the row pointed to does not exist, the classifier element is
       ignored.

       The value zeroDotZero is interpreted to match anything not
       matched by another classifier element - only one such entry may
       exist for each classifier."
    DEFVAL { zeroDotZero }
    ::= { diffServClfrElementEntry 5 }

diffServClfrElementStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a classifier element. Any writ- able variable may be
       modified whether the row is active or notInService."
    ::= { diffServClfrElementEntry 6 }

--
-- IP Six-Tuple Classification Table
--
--Classification based on six different fields in the IP header.
--Functional Data Paths may share definitions by using the same entry.
--

diffServSixTupleClfrNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused for a
       diffServSixTupleClfrId instance. If a configuring system attempts to create a
       new row in the diffServSixTupleClfrTable using this value, but an instance has
       been created or is in the process of being created, that operation will fail."
    ::= { diffServClassifier 5 }

diffServSixTupleClfrTable OBJECT-TYPE
    SYNTAX   SEQUENCE OF DiffServSixTupleClfrEntry
    MAX-ACCESS   not-accessible
    STATUS   current
    DESCRIPTION
       "A table of IP Six-Tuple Classifier filter entries that a system
       may use to identify IP traffic."
    REFERENCE





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        "[MODEL] section 4.2.2"
    ::= { diffServClassifier 6 }

diffServSixTupleClfrEntry OBJECT-TYPE
    SYNTAX       DiffServSixTupleClfrEntry
    MAX-ACCESS   not-accessible
    STATUS   current
    DESCRIPTION
       "An IP Six-Tuple Classifier entry describes a single filter."
    INDEX { diffServSixTupleClfrId }
    ::= { diffServSixTupleClfrTable 1 }

DiffServSixTupleClfrEntry ::= SEQUENCE {
    diffServSixTupleClfrId           INTEGER,
    diffServSixTupleClfrDstAddrType  InetAddressType,
    diffServSixTupleClfrDstAddr      InetAddress,
    diffServSixTupleClfrDstPrefixLength InetAddressPrefixLength,
    diffServSixTupleClfrSrcAddrType  InetAddressType,
    diffServSixTupleClfrSrcAddr      InetAddress,
    diffServSixTupleClfrSrcPrefixLength InetAddressPrefixLength,
    diffServSixTupleClfrDscp         DscpOrAny,
    diffServSixTupleClfrProtocol     Unsigned32,
    diffServSixTupleClfrDstL4PortMin InetPortNumber,
    diffServSixTupleClfrDstL4PortMax InetPortNumber,
    diffServSixTupleClfrSrcL4PortMin InetPortNumber,
    diffServSixTupleClfrSrcL4PortMax InetPortNumber,
    diffServSixTupleClfrStatus       RowStatus
}

diffServSixTupleClfrId OBJECT-TYPE
    SYNTAX         INTEGER (1..2147483647)
    MAX-ACCESS     not-accessible
    STATUS     current
    DESCRIPTION
       "An index that enumerates the Six Tuple Classifier filter
       entries.  The set of such identifiers spans the whole agent.
       Managers obtain new values for row creation in this table by
       reading diffServSixTupleClfrNextFree."

    ::= { diffServSixTupleClfrEntry 1 }

diffServSixTupleClfrDstAddrType OBJECT-TYPE
    SYNTAX         InetAddressType
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The type of IP destination address used by this classifier





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       entry."
    ::= { diffServSixTupleClfrEntry 2 }

diffServSixTupleClfrDstAddr OBJECT-TYPE
    SYNTAX         InetAddress
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The IP address to match against the packet's destination IP
       address. diffServSixTupleClfrDstPrefixLength indicates the number
       of bits that are relevant."
    ::= { diffServSixTupleClfrEntry 3 }

diffServSixTupleClfrDstPrefixLength OBJECT-TYPE
    SYNTAX         InetAddressPrefixLength
    UNITS          "bits"
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The length of the CIDR Prefix carried in
       diffServSixTupleClfrDstAddr. In IPv4 addresses, a length of 0
       indicates a match of any address; a length of 32 indicates a
       match of a single host address, and a length between 0 and 32
       indicates the use of a CIDR Prefix. IPv6 is similar, except that
       prefix lengths range from 0..128."
    DEFVAL         { 0 }
    ::= { diffServSixTupleClfrEntry 4 }

diffServSixTupleClfrSrcAddrType OBJECT-TYPE
    SYNTAX         InetAddressType
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The type of IP source address used by this classifier entry."
    ::= { diffServSixTupleClfrEntry 5 }

diffServSixTupleClfrSrcAddr OBJECT-TYPE
    SYNTAX         InetAddress
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The IP address to match against the packet's source IP address.
       diffServSixTupleClfrSrcPrefixLength indicates the number of bits
       that are relevant."
    ::= { diffServSixTupleClfrEntry 6 }

diffServSixTupleClfrSrcPrefixLength OBJECT-TYPE





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    SYNTAX         InetAddressPrefixLength
    UNITS          "bits"
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The length of the CIDR Prefix carried in
       diffServSixTupleClfrSrcAddr. In IPv4 addresses, a length of 0
       indicates a match of any address; a length of 32 indicates a
       match of a single host address, and a length between 0 and 32
       indicates the use of a CIDR Prefix. IPv6 is similar, except that
       prefix lengths range from 0..128."
    DEFVAL         { 0 }
    ::= { diffServSixTupleClfrEntry 7 }

diffServSixTupleClfrDscp OBJECT-TYPE
    SYNTAX         DscpOrAny
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The value that the DSCP in the packet must have to match this
       entry. A value of -1 indicates that a specific DSCP value has not
       been defined and thus all DSCP values are considered a match."
    DEFVAL         { -1 }
    ::= { diffServSixTupleClfrEntry 8 }

diffServSixTupleClfrProtocol OBJECT-TYPE
    SYNTAX         Unsigned32 (0..255)
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The IP protocol to match against the IPv4 protocol number or the
       IPv6 Next- Header number in the packet. A value of 255 means
       match all.  Note the protocol number of 255 is reserved by IANA,
       and Next-Header number of 0 is used in IPv6."
    DEFVAL         { 255 }
    ::= { diffServSixTupleClfrEntry 9 }

diffServSixTupleClfrDstL4PortMin OBJECT-TYPE
    SYNTAX         InetPortNumber
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The minimum value that the layer-4 destination port number in
       the packet must have in order to match this classifier entry."
    DEFVAL         { 0 }
    ::= { diffServSixTupleClfrEntry 10 }






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diffServSixTupleClfrDstL4PortMax OBJECT-TYPE
    SYNTAX         InetPortNumber
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The maximum value that the layer-4 destination port number in
       the packet must have in order to match this classifier entry.
       This value must be equal to or greater than the value specified
       for this entry in diffServSixTupleClfrDstL4PortMin."
    DEFVAL         { 65535 }
    ::= { diffServSixTupleClfrEntry 11 }

diffServSixTupleClfrSrcL4PortMin OBJECT-TYPE
    SYNTAX         InetPortNumber
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The minimum value that the layer-4 source port number in the
       packet must have in order to match this classifier entry."
    DEFVAL         { 0 }
    ::= { diffServSixTupleClfrEntry 12 }

diffServSixTupleClfrSrcL4PortMax OBJECT-TYPE
    SYNTAX         InetPortNumber
    MAX-ACCESS     read-create
    STATUS         current
    DESCRIPTION
       "The maximum value that the layer-4 source port number in the
       packet must have in oder to match this classifier entry. This
       value must be equal to or greater than the value specified for
       this entry in diffServSixTupleClfrSrcL4PortMin."
    DEFVAL         { 65535 }
    ::= { diffServSixTupleClfrEntry 13 }

diffServSixTupleClfrStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a classifier. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServSixTupleClfrEntry 14 }









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--
-- Meters
--

diffServMeter          OBJECT IDENTIFIER ::= { diffServMIBObjects 3 }

--
-- This MIB supports a variety of Meters.  It includes a specific
-- definition for Token Bucket Meter, which are but one type of
-- specification. Other metering parameter sets can be defined in other MIBs.
--
-- Multiple meter elements may be logically cascaded using their
-- diffServMeterSucceedNext and diffServMeterFailNext pointers if
-- required. One example of this might be for an AF PHB implementation
-- that uses multiple level conformance meters.
--
-- Cascading of individual meter elements in the MIB is intended to be
-- functionally equivalent to multiple level conformance determination
-- of a packet.  The sequential nature of the representation is merely
-- a notational convenience for this MIB.
--
-- srTCM meters (RFC 2697) can be specified using a single diffServMeterEntry
-- and diffServTBParamEntry. It specifies the Committed Burst Size
-- token-bucket. diffServTBParamRate reflects the Committed Information Rate.
--
-- trTCM meters (RFC 2698) can be specified using a two diffServMeterEntries
-- and diffServTBParamEntries. It specifies the Committed Burst Size in the
-- first token-bucket, and the Excess Burst Size in the second.
-- diffServTBParamRate in the first token bucket reflects the Committed
-- Information Rate.
--
-- tswTCM meters (RFC 2859) can be specified using a two diffServMeterEntries
-- and diffServTBParamEntries. It specifies the Committed Target Rate in the
-- first token-bucket, and the Excess Target Rate in the second.
-- diffServTBParamInterval in each token bucket reflects the Average Interval.

diffServMeterNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServMeterId instance. If a configuring system attempts
       to create a new row in the diffServMeterTable using this value,
       but an instance has been created or is in the process of being
       created, that operation will fail."
    ::= { diffServMeter 1 }





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diffServMeterTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServMeterEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "This table enumerates specific meters that a system may use to
       police, or shape, a stream of traffic. The traffic stream to be
       metered is determined by the Differentiated Services Functional
       Data Path element(s) upstream of the meter i.e. by the object(s)
       that point to each entry in this table. This may include all
       traffic on an interface.

       Specific meter details are to be found in table entry referenced
       by diffServMeterSpecific."
           REFERENCE
               "[MODEL] section 5.1"
    ::= { diffServMeter 2 }

diffServMeterEntry OBJECT-TYPE
    SYNTAX       DiffServMeterEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the meter table describes a single conformance level
       of a meter."
    INDEX { diffServMeterId }
    ::= { diffServMeterTable 1 }

DiffServMeterEntry ::= SEQUENCE  {
    diffServMeterId                INTEGER,
    diffServMeterSucceedNext       RowPointer,
    diffServMeterFailNext          RowPointer,
    diffServMeterSpecific          RowPointer,
    diffServMeterStatus            RowStatus
}

diffServMeterId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Meter entries. The set of such
       identifiers spans the whole agent. Managers obtain new values for
       row creation in this table by reading diffServMeterNextFree."
    ::= { diffServMeterEntry 1 }

diffServMeterSucceedNext OBJECT-TYPE





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    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "If the traffic does conform, this selects the next
       Differentiated Services Functional Data Path element to handle
       traffic for this data path. This RowPointer should point to an
       instance of one of:
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServAlgDropEntry
         diffServQEntry

       A value of zeroDotZero in this attribute indicates that no
       further Differentiated Services treatment is performed on traffic
       of this data path. The use of zeroDotZero is the normal usage for
       the last functional data path element of the current data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    DEFVAL      { zeroDotZero }
    ::= { diffServMeterEntry 2 }

diffServMeterFailNext OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "If the traffic does not conform, this selects the next
       Differentiated Services Functional Data Path element to handle
       traffic for this data path. This RowPointer should point to an
       instance of one of:
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServAlgDropEntry
         diffServQEntry

       A value of zeroDotZero in this attribute indicates no further
       Differentiated Services treatment is performed on traffic of this
       data path. The use of zeroDotZero is the normal usage for the
       last functional data path element of the current data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    DEFVAL      { zeroDotZero }





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    ::= { diffServMeterEntry 3 }

diffServMeterSpecific OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This indicates the behavior of the meter by pointing to an entry
       containing detailed parameters. Note that entries in that
       specific table must be managed explicitly.

       For example, diffServMeterSpecific may point to an entry in
       diffServTBParamTable, which contains an instance of a single set
       of Token Bucket parameters."
    ::= { diffServMeterEntry 4 }

diffServMeterStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a meter. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServMeterEntry 5 }

--
-- Token Bucket Parameter Table
--

diffServTBParam        OBJECT IDENTIFIER ::= { diffServMIBObjects 4 }

-- Each entry in the Token Bucket Parameter Table parameterize a single
-- token bucket.  Multiple token buckets can be used together to
-- parameterize multiple levels of conformance.
--
-- Note that an entry in the Token Bucket Parameter Table can be shared
-- by multiple diffServMeterTable and diffServSchedulerTable entries.
--

diffServTBParamNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServTBParamId instance. If a configuring system





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       attempts to create a new row in the diffServTBParamTable using
       this value, but an instance has been created or is in the process
       of being created, that operation will fail."
    ::= { diffServTBParam 1 }

diffServTBParamTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServTBParamEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "This table enumerates a single set of token bucket meter
       parameters that a system may use to police or shape a stream of
       traffic. Such meters are modeled here as having a single rate and
       a single burst size. Multiple entries are used when multiple
       rates/burst sizes are needed."
    REFERENCE
        "[MODEL] section 5.1"
    ::= { diffServTBParam 2 }

diffServTBParamEntry OBJECT-TYPE
    SYNTAX       DiffServTBParamEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry that describes a single set of token bucket
       parameters."
    INDEX { diffServTBParamId }
    ::= { diffServTBParamTable 1 }

DiffServTBParamEntry ::= SEQUENCE  {
    diffServTBParamId              INTEGER,
    diffServTBParamType            OBJECT IDENTIFIER,
    diffServTBParamRate            Unsigned32,
    diffServTBParamBurstSize       BurstSize,
    diffServTBParamInterval        Unsigned32,
    diffServTBParamStatus          RowStatus
}

diffServTBParamId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Token Bucket Parameter entries. The
       set of such identifiers spans the whole agent. Managers obtain
       new values for row creation in this table by reading
       diffServTBParamNextFree."





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    ::= { diffServTBParamEntry 1 }

diffServTBParamType OBJECT-TYPE
    SYNTAX       OBJECT IDENTIFIER
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The Metering/Shaping algorithm associated with the Token Bucket
       parameters.

       zeroDotZero indicates this is unknown.

       Standard values for generic algorithms:
       diffServTBParamSimpleTokenBucket, diffServTBParamAvgRate,
       diffServTBParamSrTCMBlind, diffServTBParamSrTCMAware,
       diffServTBParamTrTCMBlind, diffServTBParamTrTCMAware, and
       diffServTBParamTswTCM are specified in this MIB as OBJECT-
       IDENTITYS; additional values may be further specified in other
       MIBs."
    REFERENCE
        "[MODEL] section 5"
    ::= { diffServTBParamEntry 2 }

diffServTBParamRate OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "kilobits per second"
    MAX-ACCESS   read-create
    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. PIR and CIR in RFC 2698 for trTCM
       3. CTR and PTR in RFC 2859 for TSWTCM
       4. AverageRate used in [MODEL] section 5."
    ::= { diffServTBParamEntry 3 }

diffServTBParamBurstSize OBJECT-TYPE
    SYNTAX       BurstSize
    UNITS        "Bytes"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The maximum number of bytes in a single transmission burst. This
       attribute is used for:
       1. CBS and EBS in RFC 2697 for srTCM
       2. CBS and PBS in RFC 2698 for trTCM





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       3. Burst Size used in [MODEL] section 5."
    ::= { diffServTBParamEntry 4 }

diffServTBParamInterval OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "microseconds"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The time interval used with the token bucket.  For:
       1. Average Rate Meter, [MODEL] section 5.2.1, - Delta.
       2. Simple Token Bucket Meter, [MODEL] section 5.1,
          - time interval t.
       3. RFC 2859 TSWTCM, - AVG_INTERVAL.
       4. RFC 2697 srTCM, RFC 2698 trTCM, - token bucket
          update time interval."
    ::= { diffServTBParamEntry 5 }

diffServTBParamStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a meter. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServTBParamEntry 6 }

diffServTBParamSimpleTokenBucket OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "The value tokenBucket(2) indicates the use of Two Parameter
       Token Bucket Meter as described in [MODEL] section 5.2.3."
    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 3 }

diffServTBParamAvgRate OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "The value avgRate(3) indicates the use of Average Rate Meter as
       described in [MODEL] section 5.2.1."
    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 4 }

diffServTBParamSrTCMBlind OBJECT-IDENTITY





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    STATUS       current
    DESCRIPTION
       "The values srTCMBlind(4) and srTCMAware(5) indicate the use of
       Single Rate Three Color Marker Metering as defined by RFC 2697,
       in either the `Color Blind' and `Color Aware' mode as described
       by the RFC."
    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 5 }

diffServTBParamSrTCMAware OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "The values srTCMBlind(4) and srTCMAware(5) indicate the use of
       Single Rate Three Color Marker Metering as defined by RFC 2697,
       in either the `Color Blind' and `Color Aware' mode as described
       by the RFC."
    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 6 }

diffServTBParamTrTCMBlind OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "The values trTCMBlind(6) and trTCMAware(7) indicate the use of
       Two Rate Three Color Marker Metering as defined by RFC 2698, in
       either the `Color Blind' and `Color Aware' mode as described by
       the RFC."
    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 7 }

diffServTBParamTrTCMAware OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "Value of trTCMBlind(6) and trTCMAware(7) indicates the use of
       Two Rate Three Color Marker Metering as defined by RFC 2698, with
       `Color Blind' and `Color Aware' mode as described by the RFC."
    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 8 }

diffServTBParamTswTCM OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "The value tswTCM(8) indicates the use of Time Sliding Window
       Three Color Marker Metering as defined by RFC 2859."





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    REFERENCE
        "[MODEL] sections 5 and 7.1.2"
    ::= { diffServTBParam 9 }

















































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--
-- Actions
--

diffServAction         OBJECT IDENTIFIER ::= { diffServMIBObjects 5 }

--
-- The Action Table allows enumeration of the different
-- types of actions to be applied to a traffic flow.
--

diffServActionNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServActionId instance. If a configuring system attempts
       to create a new row in the diffServActionTable using this value,
       but an instance has been created or is in the process of being
       created, that operation will fail."
    ::= { diffServAction 1 }

diffServActionTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServActionEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The Action Table enumerates actions that can be performed to a
       stream of traffic. Multiple actions can be concatenated. For
       example, traffic exiting from a meter may be counted, marked, and
       potentially dropped before entering a queue.

       Specific actions are indicated by diffServActionSpecific which
       points to an entry of a specific action type parameterizing the
       action in detail."
    REFERENCE
        "[MODEL] section 6."
    ::= { diffServAction 2 }

diffServActionEntry OBJECT-TYPE
    SYNTAX       DiffServActionEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "Each entry in the action table allows description of one
       specific action to be applied to traffic."





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    INDEX { diffServActionId }
    ::= { diffServActionTable 1 }

DiffServActionEntry ::= SEQUENCE  {
    diffServActionId                INTEGER,
    diffServActionNext              RowPointer,
    diffServActionSpecific          RowPointer,
    diffServActionStatus            RowStatus
}

diffServActionId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Action entries. The set of such
       identifiers spans the whole agent. Managers obtain new values for
       row creation in this table by reading diffServActionNextFree."
    ::= { diffServActionEntry 1 }

diffServActionNext OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This selects the next Differentiated Services Functional Data
       Path element to handle traffic for this data path. This
       RowPointer should point to an instance of one of:
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServQEntry

       A value of zeroDotZero in this attribute indicates no further
       Differentiated Services treatment is performed on traffic of this
       data path. The use of zeroDotZero is the normal usage for the
       last functional data path element of the current data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    DEFVAL      { zeroDotZero }
    ::= { diffServActionEntry 2 }

diffServActionSpecific OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current





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    DESCRIPTION
       "A pointer to an object instance providing additional information
       for the type of action indicated by this action table entry.

       For the standard actions defined by this MIB module, this should
       point to one of the following: a diffServDscpMarkActEntry, a
       diffServCountActEntry. For other actions, it may point to an
       object instance defined in some other MIB."
    ::= { diffServActionEntry 3 }

diffServActionStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation or
       deletion of an action element. Any writable variable may be
       modified whether the row is active or notInService."
    ::= { diffServActionEntry 4 }

-- DSCP Mark Action Table
--
-- Rows of this table are pointed to by diffServActionSpecific to
-- provide detailed parameters specific to the DSCP Mark action.
--
-- A single entry in this table can be shared by multiple
-- diffServActionTable entries.
--

diffServDscpMarkActTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServDscpMarkActEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "This table enumerates specific DSCPs used for marking or
       remarking the DSCP field of IP packets. The entries of this table
       may be referenced by a diffServActionSpecific attribute."
    REFERENCE
        "[MODEL] section 6.1"
    ::= { diffServAction 3 }

diffServDscpMarkActEntry OBJECT-TYPE
    SYNTAX       DiffServDscpMarkActEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the DSCP mark action table that describes a single





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       DSCP used for marking."
    INDEX { diffServDscpMarkActDscp }
    ::= { diffServDscpMarkActTable 1 }

DiffServDscpMarkActEntry ::= SEQUENCE  {
    diffServDscpMarkActDscp          Dscp
}

diffServDscpMarkActDscp OBJECT-TYPE
    SYNTAX       Dscp
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The DSCP that this Action will store into the DSCP field of the
       subject. It is quite possible that the only packets subject to
       this Action are already marked with this DSCP. Note also that
       Differentiated Services processing may result in packet being
       marked on both ingress to a network and on egress from it, and
       that ingress and egress can occur in the same router.

       Normally, index variables are not-accessible. However, in this
       case the OID of the entry serves as a OBJECT-IDENTITY indicating
       that traffic should be marked in a certain way, and specifying a
       second object seems redundant."
    ::= { diffServDscpMarkActEntry 1 }

--
-- Count Action Table
--
-- Because the MIB structure allows multiple cascading
-- diffServActionEntry be used to describe multiple actions for a
-- data path, the counter became an optional action type.  In normal
-- implementation, either a data path has counters or it does not,
-- as opposed to being configurable. The management entity may choose
-- to read the counter or not.  Hence it is recommended for implementation
-- that have counters to always configure the count action as the first
-- of multiple actions, for example before a drop action.
--

diffServCountActNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused for a
       diffServCountActId instance. If a configuring system attempts to create a new
       row in the diffServCountActTable using this value, but an instance has been





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       created or is in the process of being created, that operation will fail."
    ::= { diffServAction 4 }

diffServCountActTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServCountActEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "This table contains counters for all the traffic passing through
       an action element."
    REFERENCE
        "[MODEL] section 6.4"
    ::= { diffServAction 5 }

diffServCountActEntry OBJECT-TYPE
    SYNTAX       DiffServCountActEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the count action table describes a single set of
       traffic counters."
    INDEX { diffServCountActId }
    ::= { diffServCountActTable 1 }

DiffServCountActEntry ::= SEQUENCE  {
    diffServCountActId           INTEGER,
    diffServCountActOctets       Counter32,
    diffServCountActHCOctets     Counter64,
    diffServCountActPkts         Counter32,
    diffServCountActHCPkts       Counter64,
    diffServCountActDiscontTime  TimeStamp,
    diffServCountActStatus       RowStatus
}

diffServCountActId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Count Action entries. The set of
       such identifiers spans the whole agent. Managers obtain new
       values for row creation in this table by reading
       diffServCountActNextFree."
    ::= { diffServCountActEntry 1 }

diffServCountActOctets OBJECT-TYPE
    SYNTAX       Counter32





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    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of octets at the Action data path element. On high-
       speed devices, this object implements the least significant 32
       bits of diffServCountActHCOctets.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServCountActDiscontTime for this
       entry."
    ::= { diffServCountActEntry 2 }

diffServCountActHCOctets OBJECT-TYPE
    SYNTAX       Counter64
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of octets at the Action data path element. This
       object should be used on high-speed interfaces.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServCountActDiscontTime for this
       entry."
    ::= { diffServCountActEntry 3 }

diffServCountActPkts OBJECT-TYPE
    SYNTAX       Counter32
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of packets at the Action data path element. On high-
       speed devices, this object implements the least significant 32
       bits of diffServCountActHCPkts.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServCountActDiscontTime for this
       entry."
    ::= { diffServCountActEntry 4 }

diffServCountActHCPkts OBJECT-TYPE
    SYNTAX       Counter64
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION





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       "The number of packets at the Action data path element. This
       object should be used on high-speed interfaces.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServCountActDiscontTime for this
       entry."
    ::= { diffServCountActEntry 5 }

diffServCountActDiscontTime OBJECT-TYPE
    SYNTAX       TimeStamp
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The value of sysUpTime on the most recent occasion at which any
       one or more of this entry's counters suffered a discontinuity. If
       no such discontinuities have occurred since the last re-
       initialization of the local management subsystem, then this
       object contains a zero value."
    ::= { diffServCountActEntry 6 }

diffServCountActStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of this entry. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServCountActEntry 7 }






















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--
-- Algorithmic Drop Table
--

diffServAlgDrop        OBJECT IDENTIFIER ::= { diffServMIBObjects 6 }

diffServAlgDropNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServAlgDropId instance. If a configuring system
       attempts to create a new row in the diffServAlgDropTable using
       this value, but an instance has been created or is in the process
       of being created, that operation will fail."
    ::= { diffServAlgDrop 1 }

diffServAlgDropTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServAlgDropEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The algorithmic drop table contains entries describing an
       element that drops packets according to some algorithm."
    REFERENCE
        "[MODEL] section 7.1.3"
    ::= { diffServAlgDrop 2 }

diffServAlgDropEntry OBJECT-TYPE
    SYNTAX       DiffServAlgDropEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry describes a process that drops packets according to
       some algorithm. Further details of the algorithm type are to be
       found in diffServAlgDropType and with more detail parameter entry
       pointed to by diffServAlgDropSpecific when necessary."
    INDEX { diffServAlgDropId }
    ::= { diffServAlgDropTable 1 }

DiffServAlgDropEntry ::= SEQUENCE  {
    diffServAlgDropId               INTEGER,
    diffServAlgDropType             INTEGER,
    diffServAlgDropNext             RowPointer,
    diffServAlgDropQMeasure         RowPointer,
    diffServAlgDropQThreshold       Unsigned32,





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    diffServAlgDropSpecific         RowPointer,
    diffServAlgDropOctets           Counter32,
    diffServAlgDropHCOctets         Counter64,
    diffServAlgDropPkts             Counter32,
    diffServAlgDropHCPkts           Counter64,
    diffServAlgDropDiscontinuityTime TimeStamp,
    diffServAlgDropStatus           RowStatus
}

diffServAlgDropId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Algorithmic Dropper entries. The
       set of such identifiers spans the whole agent. Managers obtain
       new values for row creation in this table by reading
       diffServAlgDropNextFree."
    ::= { diffServAlgDropEntry 1 }

diffServAlgDropType OBJECT-TYPE
    SYNTAX       INTEGER {
                     other(1),
                     tailDrop(2),
                     headDrop(3),
                     randomDrop(4),
                     alwaysDrop(5)
}
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The type of algorithm used by this dropper. The value other(1)
       requires further specification in some other MIB module.

       In the tailDrop(2) algorithm, diffServAlgDropQThreshold
       represents the maximum depth of the queue, pointed to by
       diffServAlgDropQMeasure, beyond which all newly arriving packets
       will be dropped.

       In the headDrop(3) algorithm, if a packet arrives when the
       current depth of the queue, pointed to by
       diffServAlgDropQMeasure, is at diffServAlgDropQThreshold, packets
       currently at the head of the queue are dropped to make room for
       the new packet to be enqueued at the tail of the queue.

       In the randomDrop(4) algorithm, on packet arrival, an Active
       Queue Management algorithm is executed which may randomly drop a





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       packet. This algorithm may be proprietary, and it may drop either
       the arriving packet or another packet in the queue.
       diffServAlgDropSpecific points to a diffServRandomDropEntry that
       describes the algorithm. For this algorithm,
       diffServAlgQThreshold is understood to be the absolute maximum
       size of the queue and additional parameters are described in
       diffServRandomDropTable.

       The alwaysDrop(5) algorithm is as its name specifies; always
       drop. In this case, the other configuration values in this Entry
       are not meaningful; There is no useful the queue are not useful.
       Therefore, diffServAlgQNext, diffServAlgQMeasure, and
       diffServAlgQSpecific are all zeroDotZero."
    ::= { diffServAlgDropEntry 2 }

diffServAlgDropNext OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This selects the next Differentiated Services Functional Data
       Path element to handle traffic for this data path. This
       RowPointer should point to an instance of one of:
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServQEntry

       A value of zeroDotZero in this attribute indicates no further
       Differentiated Services treatment is performed on traffic of this
       data path. The use of zeroDotZero is the normal usage for the
       last functional data path element of the current data path.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    ::= { diffServAlgDropEntry 3 }

diffServAlgDropQMeasure OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "Points to an entry in the diffServQTable to indicate the queue
       that a drop algorithm is to monitor when deciding whether to drop
       a packet. If the row pointed to does not exist, the algorithmic
       dropper element is considered inactive."
    ::= { diffServAlgDropEntry 4 }





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diffServAlgDropQThreshold OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "Bytes"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "A threshold on the depth in bytes of the queue being measured at
       which a trigger is generated to the dropping algorithm.

       For the tailDrop(2) or headDrop(3) algorithms, this represents
       the depth of the queue, pointed to by diffServAlgDropQMeasure, at
       which the drop action will take place. Other algorithms will need
       to define their own semantics for this threshold."
    ::= { diffServAlgDropEntry 5 }

diffServAlgDropSpecific OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "Points to a table entry that provides further detail regarding a
       drop algorithm.

       Entries with diffServAlgDropType equal to other(1) may have this
       point to a table defined in another MIB module.

       Entries with diffServAlgDropType equal to randomDrop(4) must have
       this point to an entry in diffServRandomDropTable.

       For all other algorithms specified in this MIB, this should take
       the value zeroDotzero."
    ::= { diffServAlgDropEntry 6 }

diffServAlgDropOctets OBJECT-TYPE
    SYNTAX       Counter32
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of octets that have been dropped by this drop
       process. On high-speed devices, this object implements the least
       significant 32 bits of diffServAlgDropHCOctets.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServAlgDropDiscontinuityTime for
       this Entry."
    ::= { diffServAlgDropEntry 7 }





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diffServAlgDropHCOctets OBJECT-TYPE
    SYNTAX       Counter64
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of octets that have been dropped by this drop
       process. This object should be used on high-speed interfaces.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServAlgDropDiscontinuityTime for
       this Entry."
    ::= { diffServAlgDropEntry 8 }

diffServAlgDropPkts OBJECT-TYPE
    SYNTAX       Counter32
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of packets that have been dropped by this drop
       process. On high- speed devices, this object implements the least
       significant 32 bits of diffServAlgDropHCPkts.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServAlgDropDiscontinuityTime for
       this Entry."
    ::= { diffServAlgDropEntry 9 }

diffServAlgDropHCPkts OBJECT-TYPE
    SYNTAX       Counter64
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "The number of packets that have been dropped by this drop
       process. This object should be used on high-speed interfaces.

       Discontinuities in the value of this counter can occur at re-
       initialization of the management system and at other times as
       indicated by the value of diffServAlgDropDiscontinuityTime for
       this Entry."
    ::= { diffServAlgDropEntry 10 }

diffServAlgDropDiscontinuityTime OBJECT-TYPE
    SYNTAX       TimeStamp
    MAX-ACCESS   read-only
    STATUS       current





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    DESCRIPTION
       "The value of sysUpTime on the most recent occasion at which any
       one or more of this entry's counters suffered a discontinuity. If
       no such discontinuities have occurred since the last re-
       initialization of the local management subsystem, then this
       object contains a zero value."
    ::= { diffServAlgDropEntry 11 }

diffServAlgDropStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of this entry. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServAlgDropEntry 12 }

--
-- Random Drop Table
--

diffServRandomDropNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServRandomDropId instance. If a configuring system
       attempts to create a new row in the diffServRandomDropTable using
       this value, but an instance has been created or is in the process
       of being created, that operation will fail."
    ::= { diffServAlgDrop 3 }

diffServRandomDropTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServRandomDropEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The random drop table contains entries describing a process that
       drops packets randomly. Entries in this table are pointed to by
       diffServAlgDropSpecific."
    REFERENCE
        "[MODEL] section 7.1.3"
    ::= { diffServAlgDrop 4 }

diffServRandomDropEntry OBJECT-TYPE





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    SYNTAX       DiffServRandomDropEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry describes a process that drops packets according to a
       random algorithm."
    INDEX { diffServRandomDropId }
    ::= { diffServRandomDropTable 1 }

DiffServRandomDropEntry ::= SEQUENCE  {
    diffServRandomDropId               INTEGER,
    diffServRandomDropMinThreshBytes   Unsigned32,
    diffServRandomDropMinThreshPkts    Unsigned32,
    diffServRandomDropMaxThreshBytes   Unsigned32,
    diffServRandomDropMaxThreshPkts    Unsigned32,
    diffServRandomDropProbMax          INTEGER,
    diffServRandomDropWeight           INTEGER,
    diffServRandomDropSamplingRate     INTEGER,
    diffServRandomDropStatus           RowStatus
}

diffServRandomDropId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Random Drop entries. The set of
       such identifiers spans the whole agent. Managers obtain new
       values for row creation in this table by reading
       diffServRandomDropNextFree."
    ::= { diffServRandomDropEntry 1 }

diffServRandomDropMinThreshBytes OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "bytes"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The average queue depth in bytes, beyond which traffic has a
       non-zero probability of being dropped. Changes in this variable
       may or may not be reflected in the reported value of
       diffServRandomDropMinThreshPkts."
    ::= { diffServRandomDropEntry 2 }

diffServRandomDropMinThreshPkts OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "packets"





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    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The average queue depth in packets, beyond which traffic has a
       non-zero probability of being dropped. Changes in this variable
       may or may not be reflected in the reported value of
       diffServRandomDropMinThreshBytes."
    ::= { diffServRandomDropEntry 3 }

diffServRandomDropMaxThreshBytes OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "bytes"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The average queue depth beyond which traffic has a probability
       indicated by diffServRandomDropProbMax of being dropped or
       marked. Note that this differs from the physical queue limit,
       which is stored in diffServAlgDropQThreshold. Changes in this
       variable may or may not be reflected in the reported value of
       diffServRandomDropMaxThreshPkts."
    ::= { diffServRandomDropEntry 4 }

diffServRandomDropMaxThreshPkts OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "packets"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The average queue depth beyond which traffic has a probability
       indicated by diffServRandomDropProbMax of being dropped or
       marked. Note that this differs from the physical queue limit,
       which is stored in diffServAlgDropQThreshold. Changes in this
       variable may or may not be reflected in the reported value of
       diffServRandomDropMaxThreshBytes."
    ::= { diffServRandomDropEntry 5 }


diffServRandomDropProbMax OBJECT-TYPE
    SYNTAX       INTEGER (0..1000)
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The worst case random drop probability, expressed in drops per
       thousand packets.

       For example, if in the worst case every arriving packet may be





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       dropped (100%) for a period, this has the value 1000.
       Alternatively, if in the worst case only one percent (1%) of
       traffic may be dropped, it has the value 10."
   ::= { diffServRandomDropEntry 6 }

diffServRandomDropWeight OBJECT-TYPE
    SYNTAX       INTEGER (0..65536)
    MAX-ACCESS   read-create
    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
       diffServRandomDropWeight/65536 as the coefficient for the new
       sample in the equation, and (65536 -
       diffServRandomDropWeight)/65536 as the coefficient of the old
       value.

       Implementations may limit the values of diffServRandomDropWeight
       to a subset of the possible range of values, such as powers of
       two. Doing this would facilitate implementation of the
       Exponentially Weighted Moving Average using shift instructions or
       registers."
    ::= { diffServRandomDropEntry 7 }

diffServRandomDropSamplingRate OBJECT-TYPE
    SYNTAX       INTEGER (0..1000000)
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The number of times per second the queue is sampled for queue
       average calculation.  A value of zero is used to mean that the
       queue is sampled approximately each time a packet is enqueued (or
       dequeued)."
    ::= { diffServRandomDropEntry 8 }

diffServRandomDropStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of this entry. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServRandomDropEntry 9 }







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--
-- Queue Table
--

diffServQueue          OBJECT IDENTIFIER ::= { diffServMIBObjects 7 }

--
-- An entry of diffServQTable represents a FIFO queue Differentiated
-- Services Functional Data Path element as described in [MODEL] section
-- 7.1.1. Note that the specification of scheduling parameters for a
-- queue as part of the input to a scheduler functional data path element
-- as described in [MODEL] section 7.1.2. This allows building of
-- hierarchical queuing/scheduling. A queue therefore has these attributes:
-- 1. Which scheduler will service this queue, diffServQNext.
-- 2. How the scheduler will service this queue, with respect
--    to all the other queues the same scheduler needs to service,
--    diffServQRate.
--
-- Note that upstream Differentiated Services Functional Data Path
-- elements may point to a shared diffServQTable entry as described
-- in [MODEL] section 7.1.1.
--

diffServQNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServQId instance. If a configuring system attempts to
       create a new row in the diffServQTable using this value, but an
       instance has been created or is in the process of being created,
       that operation will fail."
    ::= { diffServQueue 1 }

diffServQTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServQEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The Queue Table enumerates the individual queues."
    REFERENCE
        "[MODEL] section 7.1.1"
    ::= { diffServQueue 2 }

diffServQEntry OBJECT-TYPE
    SYNTAX       DiffServQEntry





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    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the Queue Table describes a single queue. With each
       entry belonging to one and only one data path."
    INDEX { diffServQId }
    ::= { diffServQTable 1 }

DiffServQEntry ::= SEQUENCE  {
    diffServQId                      INTEGER,
    diffServQNext                    RowPointer,
    diffServQRate                    RowPointer,
    diffServQShaper                  RowPointer,
    diffServQStatus                  RowStatus
}

diffServQId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Queue entries. The set of such
       identifiers spans the whole agent. Managers obtain new values for
       row creation in this table by reading diffServQNextFree."
    ::= { diffServQEntry 1 }

diffServQNext OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This selects the next Differentiated Services Functional Data
       Path element to handle traffic for this data path. This
       RowPointer must point to a diffServSchedulerEntry.

       A value of zeroDotZero in this attribute indicates an incomplete
       diffServQEntry instance. In such a case, the entry has no
       operational effect, since it has no parameters to give it
       meaning.

       If the row pointed to does not exist, the treatment is as if this
       attribute contains a value of zeroDotZero."
    ::= { diffServQEntry 2 }

diffServQRate OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create





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    STATUS       current
    DESCRIPTION
       "This RowPointer indicates the diffServAssuredRateEntry that the
       scheduler, pointed to by diffServQNext, should use to service
       this queue.

       If the row pointed to is zeroDotZero or does not exist, the
       minimum rate is unspecified."
    ::= { diffServQEntry 3 }

diffServQShaper OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This RowPointer indicates the diffServShapingRateEntry that the
       scheduler, pointed to by diffServQNext, should use to service
       this queue.

       If the row pointed to does not exist or is zeroDotZero, the
       maximum rate is the line speed of the interface."
    ::= { diffServQEntry 4 }

diffServQStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a queue. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServQEntry 5 }

--
-- Scheduler Table
--

diffServScheduler      OBJECT IDENTIFIER ::= { diffServMIBObjects 8 }

--
-- A Scheduler Entry represents a packet scheduler, such as a priority
-- scheduler or a WFQ scheduler. It provides flexibility for multiple
-- scheduling algorithms, each servicing multiple queues, to be used on
-- the same logical/physical interface.
--
-- Note that upstream queues or schedulers specify several of the
-- scheduler's parameters. These must be properly specified if the





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-- scheduler is to behave as expected.
--
-- The diffServSchedulerShaper attribute specifies the parameters
-- when a scheduler's output is sent to another scheduler. This is
-- used in building hierarchical queues or schedulers.
--
-- More discussion of the scheduler functional data path element is
-- in [MODEL] section 7.1.2.
--

diffServSchedulerNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServSchedulerId instance. If a configuring system
       attempts to create a new row in the diffServSchedulerTable using
       this value, but an instance has been created or is in the process
       of being created, that operation will fail."
    ::= { diffServScheduler 1 }

diffServSchedulerTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServSchedulerEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The Scheduler Table enumerates packet schedulers. Multiple
       scheduling algorithms can be used on a given data path, with each
       algorithm described by one diffServSchedulerEntry."
    REFERENCE
        "[MODEL] section 7.1.2"
    ::= { diffServScheduler 2 }

diffServSchedulerEntry OBJECT-TYPE
    SYNTAX       DiffServSchedulerEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the Scheduler Table describing a single instance of
       a scheduling algorithm."
    INDEX { diffServSchedulerId }
    ::= { diffServSchedulerTable 1 }

DiffServSchedulerEntry ::= SEQUENCE  {
    diffServSchedulerId                   INTEGER,
    diffServSchedulerNext                 RowPointer,





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    diffServSchedulerMethod               OBJECT IDENTIFIER,
    diffServSchedulerRate                 RowPointer,
    diffServSchedulerShaper               RowPointer,
    diffServSchedulerStatus               RowStatus
}

diffServSchedulerId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Scheduler entries. The set of such
       identifiers spans the whole agent. Managers obtain new values for
       row creation in this table by reading diffServSchedulerNextFree."
    ::= { diffServSchedulerEntry 1 }

diffServSchedulerNext OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This selects the next Differentiated Services Functional Data
       Path element to handle traffic for this data path. This
       RowPointer should point to an instance of one of:
         diffServSchedulerEntry
         diffServQEntry as indicated by [MODEL] section 7.1.4.

       However, this RowPointer may also point to an instance of:.
         diffServClfrElementEntry
         diffServMeterEntry
         diffServActionEntry
         diffServAlgDropEntry to extend the same data path.

       This should point to another diffServSchedulerEntry for
       implementation of multiple scheduler methods for the same data
       path, and for implementation of hierarchical schedulers.

       If the row pointed to does not exist or is zeroDotZero, no
       further Differentiated Services treatment is performed on traffic
       of this data path."

    DEFVAL       { zeroDotZero }
    ::= { diffServSchedulerEntry 2 }

diffServSchedulerMethod OBJECT-TYPE
    SYNTAX       OBJECT IDENTIFIER
    MAX-ACCESS   read-create





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    STATUS       current
    DESCRIPTION
       "The scheduling algorithm used by this Scheduler. zeroDotZero
       indicates that this is unknown.  Standard values for generic
       algorithms: diffServSchedulerPriority, diffServSchedulerWRR, and
       diffServSchedulerWFQ are specified in this MIB; additional values
       may be further specified in other MIBs."
    REFERENCE
        "[MODEL] section 7.1.2"
    ::= { diffServSchedulerEntry 3 }

diffServSchedulerRate OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This RowPointer indicates the entry in diffServAssuredRateTable
       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.  It should have the value of zeroDotZero
       when not used."
    DEFVAL      { zeroDotZero }
    ::= { diffServSchedulerEntry 4 }

diffServSchedulerShaper OBJECT-TYPE
    SYNTAX       RowPointer
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "This RowPointer indicates the entry in diffServShapingRateTable
       which indicates the maximum output rate from this scheduler. This
       attribute is used only when there is more than one level of
       scheduler.  It should have the value of zeroDotZero when not
       used."
    DEFVAL      { zeroDotZero }
    ::= { diffServSchedulerEntry 5 }

diffServSchedulerStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a scheduler. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServSchedulerEntry 6 }






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diffServSchedulerPriority OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "When the next scheduler uses Priority scheduling, defined as an
       algorithm in which the presence of data in a queue or set of
       queues absolutely precludes dequeue from another queue or set of
       queues, this indicates the relative priority of the traffic
       stream. Note that attributes from diffServAssuredRateEntry of the
       queues/schedulers feeding this scheduler are used when
       determining the next packet to schedule."
    REFERENCE
        "[MODEL] section 7.1.2"
    ::= { diffServScheduler 3 }

diffServSchedulerWRR OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "For use with diffServSchedulerMethod to indicate Weighted Round
       Robin scheduling method, defined as any algorithm in which a set
       of queues are visited in a fixed order, and varying amounts of
       traffic are removed from each queue in turn to implement an
       average output rate by class. Notice attributes from
       diffServAssuredRateEntry of the queues/schedulers feeding this
       scheduler are used when determining the next packet to schedule."
    REFERENCE
        "[MODEL] section 7.1.2"
    ::= { diffServScheduler 4 }

diffServSchedulerWFQ OBJECT-IDENTITY
    STATUS       current
    DESCRIPTION
       "For use with diffServSchedulerMethod to indicate Weighted Fair
       Queuing scheduling method, defined as any algorithm in which a
       set of queues are conceptually visited in some order, to
       implement an average output rate by class. Notice attributes from
       diffServAssuredRateEntry of the queues/schedulers feeding this
       scheduler are used when determining the next packet to schedule."
    REFERENCE
        "[MODEL] section 7.1.2"
    ::= { diffServScheduler 5 }












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--
--Assured Rate Parameters Table
--
-- The parameters used by a scheduler for its inputs or outputs are
-- maintained separately from the Queue or Scheduler table entries
-- for reusability reasons and so that they may be used by both queues
-- and schedulers.  This follows the approach for separation of data
-- path elements from parameterization that is used throughout this MIB.
-- Use of these Assured Rate Parameter Table entries by Queues and
-- Schedulers allows the modeling of hierarchical scheduling systems.
--
-- Specifically, a Scheduler has one or more inputs and one output.
-- Any queue feeding a scheduler, or any scheduler which feeds a second
-- scheduler, might specify a minimum transfer rate by pointing to an
-- Assured Rate Parameter Table entry.
--
-- The diffServAssuredRatePriority/Abs/Rel attributes are used as
-- parameters to the work-conserving portion of a scheduler:
-- "work-conserving" implies that the scheduler can continue to emit
-- data as long as there is data available at its input(s).  This has
-- the effect of guaranteeing a certain priority relative to other
-- scheduler inputs and/or a certain minimum proportion of the available
-- output bandwidth. Properly configured, this means a certain minimum
-- rate, which may be exceeded should traffic be available should there
-- be spare bandwidth after all other classes have had opportunities to
-- consume their own minimum rates.
--

diffServAssuredRateNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServAssuredRateId instance. If a configuring system
       attempts to create a new row in the diffServAssuredRateTable
       using this value, but an instance has been created or is in the
       process of being created, that operation will fail."
    ::= { diffServScheduler 6 }

diffServAssuredRateTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServAssuredRateEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The Assured Rate Parameters Table enumerates individual sets of
       scheduling parameter that can be used/reused by Queues and





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       Schedulers."
    ::= { diffServScheduler 7 }

diffServAssuredRateEntry OBJECT-TYPE
    SYNTAX       DiffServAssuredRateEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the Assured Rate Parameters Table describes a single
       set of scheduling parameters for use by one or more queues or
       schedulers."
    INDEX { diffServAssuredRateId }
    ::= { diffServAssuredRateTable 1 }

DiffServAssuredRateEntry ::= SEQUENCE  {
    diffServAssuredRateId              INTEGER,
    diffServAssuredRatePriority        Unsigned32,
    diffServAssuredRateAbs             Unsigned32,
    diffServAssuredRateRel             Unsigned32,
    diffServAssuredRateStatus          RowStatus
}

diffServAssuredRateId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Scheduler Parameter entries. The
       set of such identifiers spans the whole agent. Managers obtain
       new values for row creation in this table by reading
       diffServAssuredRateNextFree."
    ::= { diffServAssuredRateEntry 1 }

diffServAssuredRatePriority OBJECT-TYPE
    SYNTAX       Unsigned32
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The priority of this input to the associated scheduler, relative
       to the scheduler's other inputs."
    ::= { diffServAssuredRateEntry 2 }

diffServAssuredRateAbs OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "kilobits per second"
    MAX-ACCESS   read-create
    STATUS       current





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    DESCRIPTION
       "The minimum absolute rate, in kilobits/sec, that a downstream
       scheduler element should allocate to this queue. If the value is
       zero, then there is effectively no minimum rate guarantee. If the
       value is non-zero, the scheduler will assure the servicing of
       this queue to at least this rate.

       Note that this attribute value and that of diffServAssuredRateRel
       are coupled: changes to one will affect the value of the other.
       They are linked by the following equation:

         diffServAssuredRateRel = diffServAssuredRateAbs * 1000/ifSpeed

       or, if appropriate:

         diffServAssuredRateRel = diffServAssuredRateAbs * 1000/ifHighSpeed"
    REFERENCE
        "ifSpeed, ifHighSpeed from [IFMIB]"
    ::= { diffServAssuredRateEntry 3 }

diffServAssuredRateRel OBJECT-TYPE
    SYNTAX       Unsigned32
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The minimum rate that a downstream scheduler element should
       allocate to this queue, relative to the maximum rate of the
       interface as reported by ifSpeed or ifHighSpeed, in units of
       1/1000 of 1. If the value is zero, then there is effectively no
       minimum rate guarantee. If the value is non-zero, the scheduler
       will assure the servicing of this queue to at least this rate.

       Note that this attribute value and that of diffServAssuredRateAbs
       are coupled: changes to one will affect the value of the other.
       They are linked by the following equation:

         diffServAssuredRateRel = diffServAssuredRateAbs * 1000/ifSpeed

       or, if appropriate:

         diffServAssuredRateRel = diffServAssuredRateAbs * 1000/ifHighSpeed"
    REFERENCE
        "ifSpeed, ifHighSpeed from [IFMIB]"
    ::= { diffServAssuredRateEntry 4 }

diffServAssuredRateStatus OBJECT-TYPE
    SYNTAX       RowStatus





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    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a queue. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServAssuredRateEntry 5 }













































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--
-- Shaping Parameter Table
--
-- The parameters used by a scheduler for its inputs or outputs are
-- maintained separately from the Queue or Scheduler table entries
-- for reusability reasons and so that they may be used by both queues
-- and schedulers.  This follows the approach for separation of data
-- path elements from parameterization that is used throughout this MIB.
-- Use of these Shaping 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
-- Shaping Parameter Table entry. Multi-rate shapers, such as a Dual
-- Leaky Bucket algorithm, specify their rates by positing multiple
-- Shaping Parameter Entries with the same diffServShapingRateId but
-- different diffServShapingRateLevels.
--
-- The diffServShapingRateLevel/Abs/Rel attributes are used as parameters
-- to the non-work-conserving portion of a scheduler:  non-work-conserving
-- implies that the scheduler may sometimes not emit a packet, even if
-- there is data available at its input(s).  This has the effect of limiting
-- the servicing of the queue/scheduler input or output, in effect performing
-- shaping of the packet stream passing through the queue/scheduler, as
-- described in [MODEL] section 7.2.
--

diffServShapingRateNextFree OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   read-only
    STATUS       current
    DESCRIPTION
       "This object yields a value when read that is currently unused
       for a diffServShapingRateId instance. If a configuring system
       attempts to create a new row in the diffServShapingRateTable
       using this value, but an instance has been created or is in the
       process of being created, that operation will fail."
    ::= { diffServScheduler 8 }

diffServShapingRateTable OBJECT-TYPE
    SYNTAX       SEQUENCE OF DiffServShapingRateEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "The Shaping Parameter Table enumerates individual sets of
       scheduling parameter that can be used/reused by Queues and





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       Schedulers."
    ::= { diffServScheduler 9 }

diffServShapingRateEntry OBJECT-TYPE
    SYNTAX       DiffServShapingRateEntry
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An entry in the Shaping Parameter Table describes a single set
       of scheduling parameters for use by one or more queues or
       schedulers."
    INDEX { diffServShapingRateId, diffServShapingRateLevel }
    ::= { diffServShapingRateTable 1 }

DiffServShapingRateEntry ::= SEQUENCE  {
    diffServShapingRateId              INTEGER,
    diffServShapingRateLevel           INTEGER,
    diffServShapingRateAbs             Unsigned32,
    diffServShapingRateRel             Unsigned32,
    diffServShapingRateThreshold       BurstSize,
    diffServShapingRateStatus          RowStatus
}

diffServShapingRateId OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that enumerates the Shaping Parameter entries. The set
       of such identifiers spans the whole agent. Managers obtain new
       values for row creation in this table by reading
       diffServShapingRateNextFree."
    ::= { diffServShapingRateEntry 1 }

diffServShapingRateLevel OBJECT-TYPE
    SYNTAX       INTEGER (1..2147483647)
    MAX-ACCESS   not-accessible
    STATUS       current
    DESCRIPTION
       "An index that indicates which level of a multi-rate shaper is
       being given its parameters. A multi-rate shaper has some number
       of rate levels. Frame Relay's dual rate specification refers to a
       'committed' and an 'excess' rate; ATM's dual rate specification
       refers to a 'mean' and a 'peak' rate. This table is generalized
       to support an arbitrary number of rates. The committed or mean
       rate is level 1, the peak rate (if any) is the highest level rate
       configured, and if there are other rates they are distributed in





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       monotonically increasing order between them."
    ::= { diffServShapingRateEntry 2 }

diffServShapingRateAbs OBJECT-TYPE
    SYNTAX       Unsigned32
    UNITS        "kilobits per second"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The maximum rate in kilobits/sec that a downstream scheduler
       element should allocate to this queue. If the value is zero, then
       there is effectively no maximum rate limit and that the scheduler
       should attempt to be work conserving for this queue. If the value
       is non-zero, the scheduler will limit the servicing of this queue
       to, at most, this rate in a non-work-conserving manner.

       Note that this attribute value and that of diffServShapingRateRel
       are coupled: changes to one will affect the value of the other.
       They are linked by the following equation:

         diffServAssuredRateRel = diffServAssuredRateAbs * 1000/ifSpeed

       or, if appropriate:

         diffServAssuredRateRel = diffServAssuredRateAbs * 1000/ifHighSpeed"
    REFERENCE
        "ifSpeed, ifHighSpeed from [IFMIB], RFC 2963"
    ::= { diffServShapingRateEntry 3 }

diffServShapingRateRel OBJECT-TYPE
    SYNTAX       Unsigned32
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The maximum rate that a downstream scheduler element should
       allocate to this queue, relative to the maximum rate of the
       interface as reported by ifSpeed or ifHighSpeed, in units of
       1/1000 of 1. If the value is zero, then there is effectively no
       maximum rate limit and the scheduler should attempt to be work
       conserving for this queue. If the value is non-zero, the
       scheduler will limit the servicing of this queue to, at most,
       this rate in a non-work-conserving manner.

       Note that this attribute value and that of diffServShapingRateAbs
       are coupled: changes to one will affect the value of the other.
       They are linked by the following equation:






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         diffServShapingRateAbs = ifSpeed * diffServShapingRateRel/1000

       or, if appropriate:

         diffServShapingRateAbs = ifHighSpeed * diffServShapingRateRel/1000"
    REFERENCE
        "ifSpeed, ifHighSpeed from [IFMIB], RFC 2963"
    ::= { diffServShapingRateEntry 4 }

diffServShapingRateThreshold OBJECT-TYPE
    SYNTAX       BurstSize
    UNITS        "Bytes"
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The number of bytes of queue depth at which the rate of a
       multi-rate scheduler will increase to the next output rate. In
       the last conceptual row for such a shaper, this threshold is
       ignored and by convention is zero."
    REFERENCE
        "RFC 2963"
    ::= { diffServShapingRateEntry 5 }

diffServShapingRateStatus OBJECT-TYPE
    SYNTAX       RowStatus
    MAX-ACCESS   read-create
    STATUS       current
    DESCRIPTION
       "The RowStatus variable controls the activation, deactivation, or
       deletion of a queue. Any writable variable may be modified
       whether the row is active or notInService."
    ::= { diffServShapingRateEntry 6 }




















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--
-- MIB Compliance statements.
--

diffServMIBCompliances OBJECT IDENTIFIER ::= { diffServMIBConformance 1 }
diffServMIBGroups      OBJECT IDENTIFIER ::= { diffServMIBConformance 2 }

diffServMIBCompliance MODULE-COMPLIANCE
    STATUS current
    DESCRIPTION
       "This MIB may be implemented as a read-only or as a read-create
       MIB. As a result, it may be used for monitoring or for
       configuration."
    MODULE -- This Module
    MANDATORY-GROUPS {
        diffServMIBDataPathGroup, diffServMIBClfrGroup,
        diffServMIBClfrElementGroup, diffServMIBSixTupleClfrGroup,
        diffServMIBActionGroup, diffServMIBAlgDropGroup,
        diffServMIBQGroup, diffServMIBSchedulerGroup,
        diffServMIBShapingRateGroup, diffServMIBAssuredRateGroup }

-- The groups:
--        diffServMIBCounterGroup
--        diffServMIBHCCounterGroup
--        diffServMIBVHCCounterGroup
--
-- are mutually exclusive; at most one of these groups is implemented
-- for a particular interface.  When any of these groups is implemented
-- for a particular interface, then ifCounterDiscontinuityGroup from
-- [IFMIB]  must also be implemented for that interface.
--
-- Note that the diffServMIBStaticGroup is mandatory for implementations
-- that implement a read-write or read-create mode.

    GROUP diffServMIBCounterGroup
    DESCRIPTION
       "This group is mandatory for table objects indexed by ifIndex for
       which the value of the corresponding instance of ifSpeed is less
       than or equal to 20,000,000 bits/second."

    GROUP diffServMIBHCCounterGroup
    DESCRIPTION
       "This group is mandatory for table objects indexed by ifIndex for
       which the value of the corresponding instance of ifSpeed is
       greater than 20,000,000 bits/second."

    GROUP diffServMIBVHCCounterGroup





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    DESCRIPTION
       "This group is mandatory for table objects indexed by ifIndex for
       which the value of the corresponding instance of ifSpeed is
       greater than 650,000,000 bits/second."

    GROUP diffServMIBMeterGroup
    DESCRIPTION
       "This group is mandatory for devices that implement metering
       functions."

    GROUP diffServMIBTBParamGroup
    DESCRIPTION
       "This group is mandatory for devices that implement token-bucket
       metering functions."

    GROUP diffServMIBDscpMarkActGroup
    DESCRIPTION
       "This group is mandatory for devices that implement DSCP-Marking
       functions."

    GROUP diffServMIBRandomDropGroup
    DESCRIPTION
       "This group is mandatory for devices that implement Random Drop
       functions."

    GROUP diffServMIBStaticGroup
    DESCRIPTION
       "This group is mandatory for devices that allow creation of rows
       in any of the writable tables of this MIB."

    OBJECT diffServDataPathStart
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServDataPathStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServClfrDataPathStart
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServClfrStatus
    MIN-ACCESS read-only





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    DESCRIPTION
       "Write access is not required."

    OBJECT diffServClfrElementPrecedence
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServClfrElementNext
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServClfrElementSpecific
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServClfrElementStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrDstAddrType
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrDstAddr
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrDstPrefixLength
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrSrcAddrType
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrSrcAddr
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."





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    OBJECT diffServSixTupleClfrSrcPrefixLength
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrDscp
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrProtocol
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrDstL4PortMin
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrDstL4PortMax
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrSrcL4PortMin
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrSrcL4PortMax
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSixTupleClfrStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServMeterSucceedNext
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServMeterFailNext
    MIN-ACCESS read-only





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    DESCRIPTION
       "Write access is not required."

    OBJECT diffServMeterSpecific
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServMeterStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServTBParamType
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServTBParamRate
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServTBParamBurstSize
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServTBParamInterval
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServTBParamStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServActionNext
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServActionSpecific
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."





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    OBJECT diffServActionStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServCountActStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAlgDropType
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAlgDropNext
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAlgDropQMeasure
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAlgDropQThreshold
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAlgDropSpecific
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAlgDropStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropMinThreshBytes
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropMinThreshPkts
    MIN-ACCESS read-only





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    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropMaxThreshBytes
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropMaxThreshPkts
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropProbMax
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropWeight
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropSamplingRate
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServRandomDropStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServQNext
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServQRate
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServQShaper
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."





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    OBJECT diffServQStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSchedulerNext
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSchedulerMethod
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSchedulerRate
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSchedulerShaper
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServSchedulerStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAssuredRatePriority
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAssuredRateAbs
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAssuredRateRel
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServAssuredRateStatus
    MIN-ACCESS read-only





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    DESCRIPTION
       "Write access is not required."

    OBJECT diffServShapingRateAbs
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServShapingRateRel
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServShapingRateThreshold
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    OBJECT diffServShapingRateStatus
    MIN-ACCESS read-only
    DESCRIPTION
       "Write access is not required."

    ::= { diffServMIBCompliances 1 }




























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diffServMIBDataPathGroup OBJECT-GROUP
    OBJECTS {
        diffServDataPathStart, diffServDataPathStatus
    }
    STATUS current
    DESCRIPTION
       "The Data Path Group defines the MIB Objects that describe a
       functional data path."
    ::= { diffServMIBGroups 1 }

diffServMIBClfrGroup OBJECT-GROUP
    OBJECTS {
        diffServClfrDataPathStart, diffServClfrStatus
    }
    STATUS current
    DESCRIPTION
       "The Classifier Group defines the MIB Objects that describe the
       list the starts of individual classifiers."
    ::= { diffServMIBGroups 2 }

diffServMIBClfrElementGroup OBJECT-GROUP
    OBJECTS {
        diffServClfrElementPrecedence, diffServClfrElementNext,
        diffServClfrElementSpecific, diffServClfrElementStatus
    }
    STATUS current
    DESCRIPTION
       "The Classifier Element Group defines the MIB Objects that
       describe the classifier elements that make up a generic
       classifier."
    ::= { diffServMIBGroups 3 }

diffServMIBSixTupleClfrGroup OBJECT-GROUP
    OBJECTS {
        diffServSixTupleClfrDstAddrType, diffServSixTupleClfrDstAddr,
        diffServSixTupleClfrDstPrefixLength,
        diffServSixTupleClfrSrcAddrType, diffServSixTupleClfrSrcAddr,
        diffServSixTupleClfrSrcPrefixLength, diffServSixTupleClfrDscp,
        diffServSixTupleClfrProtocol, diffServSixTupleClfrDstL4PortMin,
        diffServSixTupleClfrDstL4PortMax, diffServSixTupleClfrSrcL4PortMin,
        diffServSixTupleClfrSrcL4PortMax, diffServSixTupleClfrStatus
    }
    STATUS current
    DESCRIPTION
       "The Six-Tuple Classifier Group defines the MIB Objects that
       describe a classifier element for matching on 6 fields of an IP
       and upper-layer protocol header."





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    ::= { diffServMIBGroups 4 }

diffServMIBMeterGroup OBJECT-GROUP
    OBJECTS {
        diffServMeterSucceedNext, diffServMeterFailNext,
        diffServMeterSpecific, diffServMeterStatus
    }
    STATUS current
    DESCRIPTION
       "The Meter Group defines the objects used in describing a generic
       meter element."
    ::= { diffServMIBGroups 5 }

diffServMIBTBParamGroup OBJECT-GROUP
    OBJECTS {
        diffServTBParamType, diffServTBParamRate,
        diffServTBParamBurstSize, diffServTBParamInterval,
        diffServTBParamStatus
    }
    STATUS current
    DESCRIPTION
       "The Token-Bucket Meter Group defines the objects used in
       describing a token bucket meter element."
    ::= { diffServMIBGroups 6 }

diffServMIBActionGroup OBJECT-GROUP
    OBJECTS {
        diffServActionNext, diffServActionSpecific, diffServActionStatus
    }
    STATUS current
    DESCRIPTION
       "The Action Group defines the objects used in describing a
       generic action element."
    ::= { diffServMIBGroups 7 }

diffServMIBDscpMarkActGroup OBJECT-GROUP
    OBJECTS {
        diffServDscpMarkActDscp
    }
    STATUS current
    DESCRIPTION
       "The DSCP Mark Action Group defines the objects used in
       describing a DSCP Marking Action element."
    ::= { diffServMIBGroups 8 }

diffServMIBCounterGroup OBJECT-GROUP
    OBJECTS {





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    diffServCountActOctets, diffServCountActPkts,
        diffServCountActDiscontTime, diffServCountActStatus,
        diffServAlgDropOctets, diffServAlgDropPkts
    }
    STATUS current
    DESCRIPTION
       "A collection of objects providing information specific to non-
       high speed (non- high speed interfaces transmit and receive at
       speeds less than or equal to 20,000,000 bits/second) packet-
       oriented network interfaces."
    ::= { diffServMIBGroups 9 }

diffServMIBHCCounterGroup OBJECT-GROUP
    OBJECTS {
        diffServCountActOctets, diffServCountActHCOctets,
        diffServCountActPkts, diffServCountActDiscontTime,
        diffServCountActStatus, diffServAlgDropOctets,
        diffServAlgDropHCOctets, diffServAlgDropPkts
    }
    STATUS current
    DESCRIPTION
       "A collection of objects providing information specific to high
       speed (high speed interfaces transmit and receive at speeds
       greater than 20,000,000 but less than or equals to 650,000,000
       bits/second) packet-oriented network interfaces."
    ::= { diffServMIBGroups 10 }

diffServMIBVHCCounterGroup OBJECT-GROUP
    OBJECTS {
        diffServCountActOctets, diffServCountActHCOctets,
        diffServCountActPkts, diffServCountActHCPkts,
        diffServCountActDiscontTime, diffServCountActStatus,
        diffServAlgDropOctets, diffServAlgDropHCOctets,
        diffServAlgDropPkts, diffServAlgDropHCPkts
    }
    STATUS current
    DESCRIPTION
       "A collection of objects providing information specific to very-
       high speed (very-high speed interfaces transmit and receive at
       speeds greater than 650,000,000 bits/second) packet-oriented
       network interfaces."
    ::= { diffServMIBGroups 11 }

diffServMIBAlgDropGroup OBJECT-GROUP
    OBJECTS {
        diffServAlgDropType, diffServAlgDropNext,
        diffServAlgDropDiscontinuityTime,





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        diffServAlgDropQMeasure, diffServAlgDropQThreshold,
        diffServAlgDropSpecific, diffServAlgDropStatus
    }
    STATUS current
    DESCRIPTION
       "The Algorithmic Drop Group contains the objects that describe
       algorithmic dropper operation and configuration."
    ::= { diffServMIBGroups 12 }

diffServMIBRandomDropGroup OBJECT-GROUP
    OBJECTS {
        diffServRandomDropMinThreshBytes,
        diffServRandomDropMinThreshPkts,
        diffServRandomDropMaxThreshBytes,
        diffServRandomDropMaxThreshPkts,
        diffServRandomDropProbMax,
        diffServRandomDropWeight,
        diffServRandomDropSamplingRate,
        diffServRandomDropStatus
    }
    STATUS current
    DESCRIPTION
       "The Random Drop Group augments the Algorithmic Drop Group for
       random dropper operation and configuration."

    ::= { diffServMIBGroups 13 }

diffServMIBQGroup OBJECT-GROUP
    OBJECTS {
        diffServQNext, diffServQRate, diffServQShaper,
        diffServQStatus
    }
    STATUS current
    DESCRIPTION
       "The Queue Group contains the objects that describe an
       interface's queues."
    ::= { diffServMIBGroups 14 }

diffServMIBSchedulerGroup OBJECT-GROUP
    OBJECTS {
        diffServSchedulerNext, diffServSchedulerMethod,
        diffServSchedulerRate, diffServSchedulerShaper,
        diffServSchedulerStatus
    }
    STATUS current
    DESCRIPTION
       "The Scheduler Group contains the objects that describe packet





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       schedulers on interfaces."
    ::= { diffServMIBGroups 15 }

diffServMIBAssuredRateGroup OBJECT-GROUP
    OBJECTS {
        diffServAssuredRatePriority, diffServAssuredRateAbs,
        diffServAssuredRateRel, diffServAssuredRateStatus
    }
    STATUS current
    DESCRIPTION
       "The Scheduler Parameter Group contains the objects that describe
       packet schedulers' parameters on interfaces."
    ::= { diffServMIBGroups 16 }

diffServMIBShapingRateGroup OBJECT-GROUP
    OBJECTS {
        diffServShapingRateAbs, diffServShapingRateRel,
        diffServShapingRateThreshold, diffServShapingRateStatus
    }
    STATUS current
    DESCRIPTION
       "The Scheduler Parameter Group contains the objects that describe
       packet schedulers' parameters on interfaces."
    ::= { diffServMIBGroups 17 }

diffServMIBStaticGroup OBJECT-GROUP
    OBJECTS {
        diffServClfrNextFree, diffServClfrElementNextFree,
        diffServSixTupleClfrNextFree, diffServMeterNextFree,
        diffServTBParamNextFree, diffServActionNextFree,
        diffServCountActNextFree, diffServAlgDropNextFree,
        diffServRandomDropNextFree, diffServQNextFree,
        diffServSchedulerNextFree, diffServAssuredRateNextFree,
        diffServShapingRateNextFree
    }
    STATUS current
    DESCRIPTION
       "The Static Group contains readable scalar objects used in
       creating unique identifiers for classifiers, meters, actions and
       queues. These are required whenever row creation operations on
       such tables are supported."
    ::= { diffServMIBGroups 18 }

END








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7.  Acknowledgments

This MIB builds on all the work that has gone into the Informal
Management Model for Differentiated Services Routers, Differentiated
Services PIB, and Differentiated Services Policy MIB (SNMPCONF WG).

It has been developed with the active involvement of many people, but
most notably Yoram Bernet, Steve Blake, Brian Carpenter, Dave Durham,
Michael Fine, Victor Firoiu, Jeremy Greene, Dan Grossman, Roch Guerin,
Scott Hahn, Joel Halpern, Harrie Hazewinkel, Van Jacobsen, Keith
McCloghrie, Bob Moore, Kathleen Nichols, Ping Pan, Nabil Seddigh, John
Seligson, Walter Weiss, and Bert Wijnen.


8.  Security Considerations

It is clear that this MIB is potentially useful for configuration, and
anything that can be configured can be misconfigured, with potentially
disastrous effect.

At this writing, no security holes have been identified beyond those
that SNMP Security is itself intended to address. These relate primarily
to controlled access to sensitive information and the ability to
configure a device - or which might result from operator error, which is
beyond the scope of any security architecture.

There are many read-write and read-create management objects defined in
this MIB. Such objects are often sensitive or vulnerable in some network
environments. The support for SET operations in a non-secure environment
without proper protection can have a negative effect on network
operations. The use of SNMP Version 3 is recommended over prior versions
for configuration control as its security model is improved.

There are a number of managed objects in this MIB that may contain
information that may be sensitive from a business perspective, in that
they may represent a customer's service contract or the filters that the
service provider chooses to apply to a customer's ingress or egress
traffic. There are no objects which are sensitive in their own right,
such as passwords or monetary amounts.

It may be important to control even GET access to these objects and
possibly to even encrypt the values of these object when sending them
over the network via SNMP. Not all versions of SNMP provide features for
such a secure environment.

SNMPv1 by itself is not a secure environment. Even if the network itself
is secure (for example by using IPSec), even then, there is no control





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as to who on the secure network is allowed to access and GET/SET
(read/change/create/delete) the objects in this MIB.

It is recommended that the implementers consider the security features
as provided by the SNMPv3 framework. Specifically, the use of the User-
based Security Model [12] and the View-based Access Control Model [15]
is recommended.

It is then a customer/user responsibility to ensure that the SNMP entity
giving access to an instance of this MIB, is properly configured to give
access to the objects only to those principals (users) that have
legitimate rights to indeed GET or SET (change/create/delete) them.


9.  References

[1]  Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for
     Describing SNMP Management Frameworks", RFC 2571, Cabletron
     Systems, Inc., BMC Software, Inc., IBM T. J. Watson Research, April
     1999

[2]  Rose, M., and K. McCloghrie, "Structure and Identification of
     Management Information for TCP/IP-based Internets", RFC 1155, STD
     16, Performance Systems International, Hughes LAN Systems, May 1990

[3]  Rose, M., and K. McCloghrie, "Concise MIB Definitions", RFC 1212,
     STD 16, Performance Systems International, Hughes LAN Systems,
     March 1991

[4]  M. Rose, "A Convention for Defining Traps for use with the SNMP",
     RFC 1215, Performance Systems International, March 1991

[5]  McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M.,
     and S. Waldbusser, "Structure of Management Information Version 2
     (SMIv2)", RFC 2578, STD 58, Cisco Systems, SNMPinfo, TU
     Braunschweig, SNMP Research, First Virtual Holdings, International
     Network Services, April 1999

[6]  McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M.,
     and S. Waldbusser, "Textual Conventions for SMIv2", RFC 2579, STD
     58, Cisco Systems, SNMPinfo, TU Braunschweig, SNMP Research, First
     Virtual Holdings, International Network Services, April 1999

[7]  McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M.,
     and S. Waldbusser, "Conformance Statements for SMIv2", RFC 2580,
     STD 58, Cisco Systems, SNMPinfo, TU Braunschweig, SNMP Research,
     First Virtual Holdings, International Network Services, April 1999





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[8]  Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple Network
     Management Protocol", RFC 1157, STD 15, SNMP Research, Performance
     Systems International, Performance Systems International, MIT
     Laboratory for Computer Science, May 1990.

[9]  Case, J., McCloghrie, K., Rose, M., and S. Waldbusser,
     "Introduction to Community-based SNMPv2", RFC 1901, SNMP Research,
     Inc., Cisco Systems, Inc., Dover Beach Consulting, Inc.,
     International Network Services, January 1996.

[10] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Transport
     Mappings for Version 2 of the Simple Network Management Protocol
     (SNMPv2)", RFC 1906, SNMP Research, Inc., Cisco Systems, Inc.,
     Dover Beach Consulting, Inc., International Network Services,
     January 1996.

[11] Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message
     Processing and Dispatching for the Simple Network Management
     Protocol (SNMP)", RFC 2572, SNMP Research, Inc., Cabletron Systems,
     Inc., BMC Software, Inc., IBM T. J. Watson Research, April 1999

[12] Blumenthal, U., and B. Wijnen, "User-based Security Model (USM) for
     version 3 of the Simple Network Management Protocol (SNMPv3)", RFC
     2574, IBM T. J. Watson Research, April 1999

[13] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol
     Operations for Version 2 of the Simple Network Management Protocol
     (SNMPv2)", RFC 1905, SNMP Research, Inc., Cisco Systems, Inc.,
     Dover Beach Consulting, Inc., International Network Services,
     January 1996.

[14] Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications", RFC
     2573, SNMP Research, Inc., Secure Computing Corporation, Cisco
     Systems, April 1999

[15] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access
     Control Model (VACM) for the Simple Network Management Protocol
     (SNMP)", RFC 2575, IBM T. J. Watson Research, BMC Software, Inc.,
     Cisco Systems, Inc., April 1999

[16] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction to
     Version 3 of the Internet-standard Network Management Framework",
     RFC 2570, SNMP Research, Inc., TIS Labs at Network Associates,
     Inc., Ericsson, Cisco Systems, April 1999

[ACTQMGMT]
     V. Firoiu, M. Borden "A Study of Active Queue Management for





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     Congestion Control", March 2000, In IEEE Infocom 2000,
     http://www.ieee-infocom.org/2000/papers/405.pdf

[AQMROUTER]
     V.Misra, W.Gong, D.Towsley "Fuid-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.

[DSARCH]
     S. Blake, D. Black, M. Carlson, E. Davies, Z. Wang, W. Weiss, "An
     Architecture for Differentiated Service", 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.

[DSPIB]
     M. Fine, K. McCloghrie, J. Seligson, K. Chan, S. Hahn, A. Smith,
     "Differentiated Services Policy Information Base", Internet Draft
     <draft-ietf-Differentiated Services-pib-00.txt>, March 2000

[DSTERMS]
     D. Grossman, "New Terminology for Differentiated Services",
     Internet Draft <draft-ietf-Differentiated Services-new-terms-
     02.txt>, November 1999.

[EF-PHB]
     V. Jacobson, K. Nichols, K. Poduri, "An Expedited Forwarding PHB."
     RFC 2598, June 1999.

[IFMIB]
     K. McCloghrie, F. Kastenholz, "The Interfaces Group MIB using
     SMIv2", RFC 2233, November 1997.

[INETADDRESS]
     Daniele, M., Haberman, B., Routhier, S., Schoenwaelder, J.,
     "Textual Conventions for Internet Network Addresses.", draft-ietf-
     ops-rfc2851-update-00.txt. [PRIVATE NOTE TO RFC EDITOR: YES, THIS
     IS INDEED A NORMATIVE REFERENCE. JUERGEN TELLS ME THAT HE WILL
     PUBLISH IT POSTE HASTE].





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[INTSERVMIB]
     F. Baker, J. Krawczyk, A. Sastry, "Integrated Services Management
     Information Base using SMIv2", RFC 2213, September 1997.

[MODEL]
     Y. Bernet, S. Blake, A. Smith, D. Grossman, "An Informal Management
     Model for Differentiated Services Routers", Internet Draft <draft-
     ietf-Differentiated Services-model-04.txt>, July 2000.

[POLTERM]
     F. Reichmeyer,  D. Grossman, J. Strassner, M. Condell, "A Common
     Terminology for Policy Management", Internet Draft <draft-
     reichmeyer-polterm-terminology-00.txt>, March 2000

[QUEUEMGMT]
     B. Braden et al., "Recommendations on Queue Management and
     Congestion Avoidance in the Internet", RFC 2309, April 1998.

[RED93]
     "Random Early Detection", 1993.

[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.

[SHAPER]
     "A Rate Adaptive Shaper for Differentiated Services" FC 2963,
     October 2000.




10.  Authors' Addresses

     Fred Baker
     Cisco Systems
     519 Lado Drive
     Santa Barbara, California 93111
     fred@cisco.com





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     Kwok Ho Chan
     Nortel Networks
     600 Technology Park Drive
     Billerica, MA 01821
     khchan@nortelnetworks.com

     Andrew Smith
     Allegro Networks
     6399 San Ignacio Ave
     San Jose, CA 95119
     andrew@allegronetworks.com


Table of Contents

1 The SNMP Management Framework ...................................    2
2 Relationship to other working group documents ...................    3
2.1  Relationship  to  the   Informal   Management   Model   for
     Differentiated Services Router ...............................    3
2.2 Relationship to other MIBs and Policy Management ..............    4
3 MIB Overview ....................................................    4
3.1 Processing Path ...............................................    5
3.1.1 diffServDataPathTable - The Data Path Table .................    6
3.2 Classifier ....................................................    6
3.2.1 diffServClfrElementTable - The Classifier Element Table .....    7
3.2.2 diffServSixTupleClfrTable - The Six-Tuple Classifier Table
     ..............................................................    8
3.3 Metering Traffic ..............................................    9
3.3.1 diffServMeterTable - The Meter Table ........................   10
3.3.2 diffServTBParamTable - The Token Bucket  Parameters  Table
     ..............................................................   10
3.4 Actions applied to packets ....................................   11
3.4.1 diffServActionTable - The Action Table ......................   12
3.4.2 diffServCountActTable - The Count Action Table ..............   12
3.4.3 diffServDscpMarkActTable - The Mark Action Table ............   13
3.4.4 diffServAlgDropTable - The Algorithmic Drop Table ...........   13
3.4.5 diffServRandomDropTable - The Random Drop Parameters Table
     ..............................................................   14
3.5 Queuing and Scheduling of Packets .............................   16
3.5.1 diffServQTable - The Class or Queue Table ...................   16
3.5.2 diffServSchedulerTable - The Scheduler Table ................   17
3.5.3 diffServAssuredRateTable - The Assured Rate Table ...........   17
3.5.4 diffServShapingRateTable - The Shaping Rate Table ...........   18
3.5.5 Using queues and schedulers together ........................   18
3.6 Example configuration for AF and EF ...........................   21
3.6.1 AF and EF Ingress Interface Configuration ...................   21
3.6.1.1 Classification In The Example .............................   23





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3.6.1.2 AF Implementation On an Ingress Edge Interface ............   24
3.6.1.2.1 AF Metering On an Ingress Edge Interface ................   24
3.6.1.2.2 AF Actions On an Ingress Edge Interface .................   24
3.6.1.3 EF Implementation On an Ingress Edge Interface ............   25
3.6.1.3.1 EF Metering On an Ingress Edge Interface ................   25
3.6.1.3.2 EF Actions On an Ingress Edge Interface .................   25
3.7 AF and EF Egress Edge Interface Configuration .................   25
3.7.1 Classification On an Egress Edge Interface ..................   25
3.7.2 AF Implementation On an Egress Edge Interface ...............   27
3.7.2.1 AF Metering On an Egress Edge Interface ...................   27
3.7.2.2 AF Actions On an Egress Edge Interface ....................   28
3.7.2.3 AF Rate-based Queuing On an Egress Edge Interface .........   28
3.7.3 EF Implementation On an Egress Edge Interface ...............   28
3.7.3.1 EF Metering On an Egress Edge Interface ...................   29
3.7.3.2 EF Actions On an Egress Edge Interface ....................   29
3.7.3.3 EF Priority Queuing On an Egress Edge Interface ...........   29
4 Conventions used in this MIB ....................................   29
4.1 The use of RowPointer to indicate data path linkage ...........   29
4.2 The use of RowPointer to indicate parameters ..................   30
4.3 Conceptual row creation and deletion ..........................   31
5 Extending this MIB ..............................................   31
6 MIB Definition ..................................................   33
7 Acknowledgments .................................................  104
8 Security Considerations .........................................  104
9 References ......................................................  105
10 Authors' Addresses .............................................  108


























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11.  Full Copyright

   Copyright (C) The Internet Society (2000). All Rights Reserved.

   This document and translations of it may be copied and furnished to
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   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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