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RFC 3287

Proposed STD
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Remote Monitoring MIB Extensions for Differentiated Services

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Network Working Group                                         A. Bierman
Request for Comments: 3287                           Cisco Systems, Inc.
Category: Standards Track                                      July 2002


                  Remote Monitoring MIB Extensions for
                        Differentiated Services

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2002).  All Rights Reserved.

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   In particular, it describes managed objects used for monitoring
   Differentiated Services (DS) Codepoint usage in packets which contain
   a DS field, utilizing the monitoring framework defined in the RMON-2
   (Remote Network Monitoring Management Version 2) MIB.

Table of Contents

   1 The SNMP Network Management Framework ........................... 2
   2 Overview ........................................................ 3
   2.1 Terms ......................................................... 4
   2.2 Relationship to Differentiated Services ....................... 4
   2.3 Relationship to the Remote Monitoring MIBs .................... 5
   3 MIB Structure ................................................... 6
   3.1 DSCP Counter Aggregation ...................................... 7
   3.1.1 Counter Aggregation Configuration ..........................  8
   3.2 MIB Group Overview ...........................................  8
   3.2.1 DSCP Counter Aggregation Control Group .....................  9
   3.2.2 DS Statistics Group ........................................ 10
   3.2.3 DS Protocol Distribution Group ............................. 10
   3.2.4 DS Host Distribution Group ................................. 11
   3.2.5 DSMON Capabilities Group ................................... 12
   3.2.6 DS Matrix Distribution Group ............................... 13
   3.3 RMON vs. DSMON Indexing Structure ............................ 13
   4 Definitions .................................................... 16

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   5 Counter Aggregation Configuration Usage Examples .............. 108
   5.1 Step 1: Unlock the Counter Aggregation Configuration ........ 109
   5.2 Step 2: Check the  Maximum  number  of  Counter  Aggregation
        Groups ..................................................... 109
   5.3  Step  3:  Check if the counter aggregation profiles already
        exist ...................................................... 109
   5.4 Step 4: Create the Counter Aggregation Control Entries ...... 109
   5.5 Step 5: Create the Counter  Aggregation  Group  Descriptions
        ............................................................ 110
   5.6 Step 6: Create the Counter Aggregation Profile Mappings ..... 112
   5.7 Step 7: Lock the Counter Aggregation Configuration .......... 115
   6 Intellectual Property ......................................... 115
   7 Acknowledgements .............................................. 116
   8 References .................................................... 116
   9 Security Considerations ....................................... 118
   10 Author's Address ............................................. 119
   11 Full Copyright Statement ..................................... 120

1.  The SNMP Network Management Framework

   The SNMP Management Framework presently consists of five major
   components:

   o  An overall architecture, described in RFC 2571 [RFC2571].

   o  Mechanisms for describing and naming objects and events for the
      purpose of management.  The first version of this Structure of
      Management Information (SMI) is called SMIv1 and is described in
      STD 16, RFC 1155 [RFC1155], STD 16, RFC 1212 [RFC1212] and RFC
      1215 [RFC1215].  The second version, called SMIv2, is described in
      STD 58, RFC 2578 [RFC2578], RFC 2579 [RFC2579] and RFC 2580
      [RFC2580].

   o  Message protocols for transferring management information.  The
      first version of the SNMP message protocol is called SNMPv1 and is
      described in STD 15, RFC 1157 [RFC1157].  A second version of the
      SNMP message protocol, which is not an Internet standards track
      protocol, is called SNMPv2c and is described in RFC 1901 [RFC1901]
      and RFC 1906 [RFC1906].  The third version of the message protocol
      is called SNMPv3 and is described in RFC 1906 [RFC1906], RFC 2572
      [RFC2572] and RFC 2574 [RFC2574].

   o  Protocol operations for accessing management information.  The
      first set of protocol operations and associated PDU formats is
      described in STD 15, RFC 1157 [RFC1157].  A second set of protocol
      operations and associated PDU formats is described in RFC 1905
      [RFC1905].

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   o  A set of fundamental applications described in RFC 2573 [RFC2573]
      and the view-based access control mechanism described in RFC 2575
      [RFC2575].

   A more detailed introduction to the current SNMP Management Framework
   can be found in RFC 2570 [RFC2570].

   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.

2.  Overview

   There is a need for a standardized way of monitoring the network
   traffic usage of Differentiated Services (DS) [RFC2474] codepoint
   values.  Each DS codepoint (DSCP) value may be given a different
   treatment by a forwarding device, and this affects which packets get
   dropped or delayed during periods of network congestion.

   The IETF DIFFSERV working group has redefined the semantics of the
   Type of Service (TOS) octet in the IP header, which is now called the
   'DS field'.  The 6-bit Codepoint (DSCP) portion is contained in the
   DS field, which provides for 64 different packet treatments for the
   implementation of differentiated network services.

   By polling DSCP usage counters, an NMS can determine the network
   throughput for traffic associated with different DSCPs.  This data
   can then be analyzed in order to 'tune' DSCP 'allocations' within a
   network, based on the Quality of Service (QoS) policies for that
   network.

   Remote monitoring agents are typically implemented as independent
   software (and sometimes hardware) components, called 'RMON probes'.
   Note that DSMON-capable RMON probes simply collect and aggregate
   statistics, based on criteria (which includes the DSCP value) that
   can be determined by inspecting the contents of monitored packets and
   do not in any way monitor any aspect of a DS forwarding device's
   internal statistics.

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2.1.  Terms

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in BCP 14, RFC 2119.
   [RFC2119]

   This document uses some terms that need introduction:

   DataSource
      A source of data for monitoring purposes.  This term is used
      exactly as defined in the RMON-2 MIB [RFC2021].

   protocol
      A specific protocol encapsulation, as identified for monitoring
      purposes.  This term is used exactly as defined in the RMON
      Protocol Identifiers document [RFC2074].

   Counter Aggregation Group
      A group of statistical counters that are being combined in the
      agent to produce one aggregated counter.  Refer to sections 3.1
      and 3.2.1 for details on counter aggregation groups.

   Counter Aggregation Profile
      Also called 'profile'; A complete set of counter aggregation group
      mappings for DSCP values (i.e., 64 mappings, for each DSCP values
      0 to 63), which are applied to all monitored packets on a
      particular data source and/or DSMON collection.  Refer to sections
      3.1 and 3.2.1 for details on counter aggregation profiles.

   High Capacity Monitoring
      The generic capability to collect and store statistics with an
      internal range of 64 bits (e.g., Counter64).  This term does not
      refer to implementation of the High Capacity RMON MIB [RFC3273].

2.2.  Relationship to Differentiated Services

   The DSMON MIB is a product of the RMONMIB WG, not the DIFFSERV WG,
   and it focuses on extending several existing RMON mechanisms to
   support additional packet classification, based on DSCP values
   observed in monitored packets.  This document assumes the reader is
   familiar with the DS Architecture [RFC2475].

   It is expected that complex management applications will use the
   counters in this MIB to help analyze DS-related throughput.  It is
   expected that other metrics, such as delay and jitter, will also be
   analyzed, but support for other metrics is outside the scope of this
   document.

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2.3.  Relationship to the Remote Monitoring MIBs

   This MIB is intended to be implemented in Remote Monitoring (RMON)
   probes, which support the RMON-2 MIB [RFC2021].  Such probes may be
   stand-alone devices, or may be co-located with other networking
   devices (e.g., ethernet switches and repeaters).

   The DSMON functions are intended to be implemented in conjunction
   with the associated RMON functions, but the MIB is independent of all
   other RMON data tables.

   Several concepts and even MIB objects from the RMON MIBs are used in
   the DSMON MIB:

   Protocol Directory
      The RMON-2 MIB [RFC2021] defines the protocolDirTable, which is a
      directory of all the protocols that the RMON-2 agent is capable of
      decoding and counting.  The DSMON MIB utilizes this directory to
      identify the protocols detected in monitored packets.  The
      protocolDirLocalIndex MIB object is used to identify protocol
      encapsulations in all DSMON data tables which classify and
      aggregate by protocol type in some manner.  Note that the
      protocolDirTable is used for protocol identification only,
      independent of DSCP classification.

   TimeFilter
      The RMON-2 TimeFilter textual convention provides a mechanism to
      retrieve only rows which have been created or modified since the
      last polling interval (for a particular NMS).  The DSMON MIB uses
      this textual convention in the large data tables, in order to
      minimize polling impact.

   Zero-Based Counters
      Since counters are instantiated by management action, as in the
      RMON MIBs, the DSMON MIB uses zero-based counters in all data
      collection tables.  Specifically, the ZeroBasedCounter32 textual
      convention from the RMON-2 MIB [RFC2021] and the
      ZeroBasedCounter64 textual convention (defined in the HCNUM-TC MIB
      [RFC2856]) are used to define counter objects in this MIB.

   High Capacity Counters
      The DSMON MIB uses the 'SNMPv1 coexistence' strategy adopted by
      the RMONMIB WG.  That is, where a 64-bit counter is provided, a
      32-bit version of the counter, and a 32-bit overflow counter are
      also provided.

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   TopN Reports
      The DSMON MIB uses the same TopN reporting MIB structure as the
      RMON-2 MIB [RFC2021].  TopN reporting can greatly reduce the
      polling overhead required to analyze DSCP usage patterns.

   Some DESCRIPTION clauses for DSMON objects are very similar to those
   for existing RMON-2 or HC-RMON objects.  This is intentional, since
   the semantics of the DSMON features are designed to be as close to
   existing RMON feature as possible, to allow developers and users some
   level of 'MIB re-use'.

3.  MIB Structure

              Figure 1: DSMON MIB Functional Structure

       +--------------+     +---------------+
       |              |     |    Counter    |
       |    DSMON     |     |  Aggregation  |
       | Capabilities |     |    Control    |
       |              |     |               |
       +--------------+     +---------------+
                                   |
                                   |
    +------------------------------+----------------------------+
    |                              V                            |
    |                                                           |
    | +-----------+ +-----------+ +-----------+ +------------+  |
    | |           | |           | |           | |            |  |
    | | Data Src  | | Protocol  | | Net. Host | | App Matrix |  |
    | |   Stats   | |  Stats    | |   Stats   | |    Stats   |  |
    | |           | |           | |           | |            |  |
    | +-----------+ +-----------+ +-----------+ +------------+  |
    |                     |             |             |         |
    |                     V             V             V         |
    |               +-----------+ +-----------+ +------------+  |
    |               |           | |           | |            |  |
    |               | Protocol  | | Net. Host | | App Matrix |  |
    |               |   TopN    | |   TopN    | |    TopN    |  |
    |               |           | |           | |            |  |
    |               +-----------+ +-----------+ +------------+  |
    |                                                           |
    |                     Data Collection                       |
    |                                                           |
    +-----------------------------------------------------------+

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   The DSMON MIB can divided into three functional components:

   -  DSMON Capabilities
      Describes which DSMON object groups are supported by the agent on
      at least one data source.

   -  Counter Aggregation Control
      Controls how individual DIFFSERV codepoint counters are aggregated
      in DSMON data collections.

   -  Data Collection
      Controls how individual statistical collections are maintained by
      the agent and reported to management applications.  The individual
      boxes within the Data Collection box represent the DSMON data
      collections (described in section 3.2):

         -  Data Source Statistics
         -  Protocol Statistics
         -  Protocol Statistics TopN Reporting
         -  Network Protocol Host Statistics
         -  Network Protocol Host Statistics TopN Reporting
         -  Application Protocol Matrix Statistics
         -  Application Protocol Matrix Statistics TopN Reporting

3.1.  DSCP Counter Aggregation

   A mechanism to configure the agent to internally aggregate counters
   is provided, based on DSCP values.  This is desirable for several
   reasons:

   -  agent data reduction
      An agent implementation can potentially reduce the number of
      counters maintained for a given DSMON collection.

   -  agent data collection limitations
      Some implementation strategies might provide for a limited number
      of high-speed (e.g., hardware-based) counters for either single or
      aggregated codepoints.

   -  application data retrieval reduction
      Applications that would otherwise aggregate counters for
      individual codepoints can move that function to the agent in order
      to reduce the polling overhead on the application, the network,
      and the agent device.

   -  some unused codepoints at this time
      Various DSCP values may be expected to remain unused on a given
      network, and may be aggregated for counting purposes.

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   -  some DSCP values are mapped to the same packet treatment
      A network administrator may align the counter aggregation
      configuration of the monitoring device with the DS configuration,
      and aggregate statistics for DSCP values which are expected to
      receive the same treatment by the forwarding devices.

3.1.1.  Counter Aggregation Configuration

   The configuration of DSCP counter to counter aggregation group
   mappings is managed in a global manner, so that these settings can be
   shared across several DSMON collections and/or data sources.  One
   complete set of DSCP counter mappings is called a counter aggregation
   profile.  The DSMON control tables are very similar to existing
   RMON-2 control tables, except they contain an extra parameter to
   identify the counter aggregation profile the agent should use for the
   collection.

   The appropriate granularity for counter aggregation profile
   assignment may be the data source, but in order to reduce MIB
   complexity (by avoiding an extra layer of tables), an instance of the
   counter aggregation profile parameter exists for each collection.  An
   agent MAY choose to restrict configurations such that all DSMON data
   collections for the same data source must use the same counter
   aggregation profile.

   The DSMON MIB supports the configuration of an arbitrary number of
   counter aggregation profiles.  There is a top-level counter
   aggregation control table, which contains one entry for each counter
   aggregation profile.  A subordinate counter aggregation profile table
   provides information about each DSCP counter to counter aggregation
   group mapping in each profile.  An auxiliary counter aggregation
   group table also provides descriptive information about each counter
   aggregation group in each profile.  Refer to section 3.2.1 for
   details on these MIB objects.

3.2.  MIB Group Overview

   The DSMON MIB contains six groups of MIB objects:

   -  dsmonAggregateControl group
      Controls the configuration of counter aggregation groups for the
      purpose of reducing the total number of counters maintained by the
      agent.

   -  dsmonStatsObjects group
      Report per counter aggregation group distribution statistics for a
      particular RMON dataSource.

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   -  dsmonPdistObjects group
      Report per counter aggregation group distribution statistics for
      each application protocol detected on a particular RMON
      dataSource.

   -  dsmonHostObjects group
      Report host address distribution statistics for each counter
      aggregation group, detected on a particular RMON dataSource.

   -  dsmonCapsObjects group
      Report the static DSMON MIB functional capabilities of the agent
      implementation.

   -  dsmonMatrixObjects group
      Report host address pair distribution statistics for each counter
      aggregation group, detected on a particular RMON dataSource.

3.2.1.  DSCP Counter Aggregation Control Group

   This group contains 4 scalar objects and three tables, and is used by
   a management station to configure counter aggregation profiles.

   The dsmonMaxAggGroups scalar is a read-only integer which indicates
   the maximum number of counter aggregation groups that the agent will
   allow to be configured into a single aggregation profile.  This value
   SHOULD be equal to 64 (the number of codepoints), but an agent MAY
   limit the number of counter aggregation groups because of resource
   limitations (e.g., small number of hardware-based counters).  At
   least one counter aggregation profile containing at least two counter
   aggregation groups SHOULD be supported by the agent.  (Note that
   classifying all DSCP counters into the same statistical 'bucket' may
   yield a redundant data collection, which can be achieved more easily
   with an HC-RMON or RMON-2 collection instead.)

   The dsmonAggControlLocked scalar is used as a top level switch,
   controlling most write access to the dsmonAggControlTable,
   dsmonAggProfileTable, and dsmonAggGroupTable.  (The
   dsmonAggControlOwner object is the only exception.)  All active DSMON
   collection data is deleted, and collection suspended, while this
   object is equal to 'false', since the meaning of one or more counter
   aggregation control tables may change when it is set back to 'true'.

   The dsmonAggControlChanges counter and dsmonAggControlLastChangeTime
   timestamp can be used by a management station to detect that the
   codepoint to counter aggregation group mappings may have changed
   between polls.

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   The dsmonAggControlTable is a read-create table which contains one
   entry for each counter aggregation profile configured on the agent.
   Each entry is identified by a dsmonAggControlIndex value, which is
   also used as the major index into the dsmonAggProfileTable and
   dsmonAggGroupTable.  The DSMON control tables with DataSource objects
   select a counter aggregation profile by referencing this index value.

   The dsmonAggProfileTable is a read-write table which contains 64 rows
   for each associated entry in the dsmonAggControlTable, which MUST be
   indexed from 0 to 63.  The agent creates this set of 64 instances
   when the associated dsmonAggControlEntry is activated, and deletes
   them when that dsmonAggControlEntry is deactivated.  Each of the 64
   rows represents a conceptual DSCP counter, identified by the same
   dsmonAggProfileDSCP value, and contains the DSCP counter to counter
   aggregation group mapping for that DSCP counter, in the indicated
   profile.  The agent SHOULD use the value zero as the initial counter
   aggregation group assignment for each entry in this table.

   The dsmonAggGroupTable contains an administratively assigned
   descriptive label for each configured counter aggregation group.
   This table is not required to be fully configured in order for data
   collection to occur, since collections are identified by the agent
   with integer indices.  It is provided to allow the agent to store a
   descriptive string for each configured counter aggregation group.
   There is no attempt made to convey any real semantics for each
   counter aggregation group.  A management station MAY choose not to
   configure entries in this table.

3.2.2.  DS Statistics Group

   This group contains two tables, the dsmonStatsControlTable and the
   dsmonStatsTable, and supports counter aggregation group distribution
   statistics for half and full-duplex, low and high speed interfaces.
   Packet and octets distributions are maintained in the dsmonStatsTable
   for each active control row in the dsmonStatsControlTable.

   This group provides the lowest statistics granularity in the DSMON
   MIB.  It is expected that a management application will analyze
   certain DS deployment or performance problems by first examining the
   counter aggregation group distribution for an entire data source with
   this group.

3.2.3.  DS Protocol Distribution Group

   This group contains two tables for statistics collection,
   (dsmonPdistCtlTable and dsmonPdistStatsTable), and two tables for a
   'Top N' reporting function for the collected statistics
   (dsmonPdistTopNCtlTable and dsmonPdistTopNTable).

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   The dsmonPdistCtlTable and dsmonPdistStatsTable tables provide
   counter aggregation group distribution statistics for each selected
   protocol encapsulation in packets monitored on a particular
   dataSource.  Packet and octets distributions (per counter aggregation
   group per protocol) are maintained in the dsmonPdistStatsTable for
   each active control row in the dsmonPdistCtlTable.

   Due to the potentially large number of entries, the DS Protocol
   Distribution is different from the RMON-2 protocol distribution group
   in several ways:

   -  maximum desired entries parameter added to the control table

   -  inserts and deletes counters added to the control table

   -  support for LRU garbage collection in the dsmonPdistStatsTable

   -  TimeFilter index added to the dsmonPdistStatsTable

   -  the selection of protocols is not configurable.  Rather than
      select individual protocols to monitor, (e.g., via a
      'supportedOn/Off' extension to the protocolDirTable [RFC 2021]), a
      simplified configuration mechanism is provided.  Since DSCP usage
      statistics are most interesting at the application layer, the
      dsmonPdistStatsTable is 'hardwired' to select only application
      layer (i.e., 'terminal') protocols for statistical analysis.

   The TopN feature requires two additional tables: the
   dsmonPdistTopNCtlTable and the dsmonPdistTopNTable, and supports
   periodic usage reporting for the statistics maintained in the
   dsmonPdistStatsTable.  This feature allows for simple periodic
   retrieval of the most used application/counter aggregation group
   combinations.

3.2.4.  DS Host Distribution Group

   This group contains two tables for statistics collection,
   (dsmonHostCtlTable and dsmonHostTable), and two tables for a 'Top N'
   reporting function for the collected statistics
   (dsmonHostTopNCtlTable and dsmonHostTopNTable).

   The dsmonHostCtlTable and dsmonHostTables provide host distribution
   statistics for each counter aggregation group detected in packets
   monitored on a particular dataSource.  The DSMON Host collection is
   similar to the RMON-2 network layer host collection (nlHostTable).
   There is no DSMON application host table defined at this time.

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   It is expected that a management application will analyze certain DS
   deployment or performance problems by first determining the high
   priority DSCP values to examine (beyond the scope of this document)
   and then examining the dsmonHostTable or dsmonHostTopNTable
   statistics to determine which hosts are using the selected counter
   aggregation groups.

   Packet and octets distributions (in and out, per counter aggregation
   group per host) are maintained in the dsmonHostTable for each active
   control row in the dsmonHostCtlTable.

   The DS Host Distribution is different from the RMON-2 network layer
   host group in two ways:

   -  the protocolDirLocalIndex in the INDEX clause MUST identify a
      network protocol encapsulation which contains a DS field (e.g.,
      IPv4 or IPv6).  If a protocol encapsulation with multiple network
      layers is specified, then associated entries in this table refer
      to the innermost network protocol layer.

   -  the dsmonHostCtlTable supports limited IPv4 and IPv6 prefix
      aggregation by allowing the number of 'monitored address bits' in
      each address to be configured for each collection.  The agent will
      zero out the selected number of rightmost address bits for
      counting purposes.  This configuration parameter can dramatically
      reduce the number of entries which must be maintained by the
      agent, which should reduce CPU and memory resource requirements on
      the agent, and reduce polling overhead on the network and the
      management station.  However, only one mask can be configured for
      each address type, rather than multiple different length masks for
      each address type, based on prefix value.

   The TopN feature requires two additional tables: the
   dsmonHostTopNCtlTable and the dsmonHostTopNTable, and supports
   periodic usage reporting for the statistics maintained in the
   dsmonHostTable.  This feature allows for simple periodic retrieval of
   the most used IP-host/DSCP combinations.

3.2.5.  DSMON Capabilities Group

   This group contains a single read-only scalar object,
   dsmonCapabilities, which provides an indication of the MIB groups
   within this MIB that the agent supports.

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3.2.6.  DS Matrix Distribution Group

   This group contains three tables for statistics collection,
   (dsmonMatrixCtlTable, dsmonMatrixSDTable, and dsmonMatrixDSTable),
   and two tables for a 'Top N' reporting function for the collected
   statistics (dsmonMatrixTopNCtlTable and dsmonMatrixTopNTable).

   The dsmonMatrixCtlTable, dsmonMatrixSDTable, and dsmonMatrixDSTable
   provide host-pair distribution statistics for each counter
   aggregation group detected in packets monitored on a particular
   dataSource.  The DSMON Matrix collection is similar to the RMON-2
   application layer matrix collection (alMatrixSDTable and
   alMatrixDSTable).  There is no DSMON network layer matrix table
   defined at this time.

   It is expected that a management application will analyze certain DS
   deployment or performance problems by first determining the high
   priority DSCP values to examine (beyond the scope of this document)
   and then examining the dsmonMatrixSDTable, dsmonMatrixDSTable, and/or
   dsmonMatrixTopNTable statistics to determine which host-pairs are
   using the selected counter aggregation groups.

   Packet and octets distributions (source to destination, per counter
   aggregation group per host-pair) are maintained in the
   dsmonMatrixSDTable and dsmonMatrixDSTable for each active control row
   in the dsmonMatrixCtlTable.

   The TopN feature requires two additional tables: the
   dsmonMatrixTopNCtlTable and the dsmonMatrixTopNTable, and supports
   periodic usage reporting for the statistics maintained in the
   dsmonMatrixSDTable.  This feature allows for simple periodic
   retrieval of the most used IP-host-pair/DSCP combinations.

3.3.  RMON vs. DSMON Indexing Structure

   The DSMON-MIB control and data tables are very similar in structure
   and look-and-feel to existing RMON-2 and HC-RMON control tables for
   the comparable feature, in order to maintain consistent agent
   behavior and functionality across RMON MIBs.  The DSMON data tables
   are indexed as closely as possible to the comparable RMON-2 or HC-
   RMON tables, with the addition of an index component for DSCP-based
   classification (i.e. dsmonAggGroup).  Refer to Table 1 for a
   comparison of DSMON indexing structure with similar existing RMON
   features.

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                     Table 1: DSMON Indexing Comparison

           Existing RMON                 DSMON
    --------------------------------------------------------------------
                      Full Duplex Interface Statistics

    mediaIndependentEntry            | dsmonStatsControlEntry
       mediaIndependentIndex         |    dsmonStatsControlIndex
                                     | dsmonStatsEntry
                                     |    dsmonStatsControlIndex,
                                     |    dsmonAggGroupIndex
    ---------------------------------+------------------------------
                              Protocol Statistics

    protocolDistControlEntry         | dsmonPdistCtlEntry
       protocolDistControlIndex      |    dsmonPdistCtlIndex
    protocolDistStatsEntry           | dsmonPdistStatsEntry
       protocolDistControlIndex,     |    dsmonPdistCtlIndex,
       protocolDirLocalIndex         |    dsmonPdistTimeMark,
                                     |    dsmonAggGroupIndex,
                                     |    protocolDirLocalIndex
    ---------------------------------+--------------------------------
                         Protocol TopN Distribution

                                     | dsmonPdistTopNCtlEntry
                                     |    dsmonPdistTopNCtlIndex
                  none               | dsmonPdistTopNEntry
                                     |    dsmonPdistTopNCtlIndex,
                                     |    dsmonPdistTopNIndex
    ---------------------------------+--------------------------------
                            Network Host Statistics

     hlHostControlEntry              | dsmonHostCtlEntry
        hlHostControlIndex           |    dsmonHostCtlIndex
     nlHostEntry                     | dsmonHostEntry
        hlHostControlIndex,          |    dsmonHostCtlIndex,
        nlHostTimeMark,              |    dsmonHostTimeMark,
        protocolDirLocalIndex,       |    dsmonAggGroupIndex,
        nlHostAddress                |    protocolDirLocalIndex,
                                     |    dsmonHostAddress
    ---------------------------------+--------------------------------

Top      ToC       Page 15 
                  Table 1 (Continued): DSMON Indexing Comparison

           Existing RMON                 DSMON

    ---------------------------------+--------------------------------
                         Network Host TopN Distribution

                                     | dsmonHostTopNCtlEntry
                                     |    dsmonHostTopNCtlIndex
                  none               | dsmonHostTopNEntry
                                     |    dsmonHostTopNCtlIndex,
                                     |    dsmonHostTopNIndex
    ---------------------------------+--------------------------------
                       Application Matrix Statistics

     hlMatrixControlEntry            | dsmonMatrixCtlEntry
        hlMatrixControlIndex         |    dsmonMatrixCtlIndex
     alMatrixSDEntry                 | dsmonMatrixSDEntry
        hlMatrixControlIndex,        |    dsmonMatrixCtlIndex,
        alMatrixSDTimeMark,          |    dsmonMatrixTimeMark,
        protocolDirLocalIndex,       |    dsmonAggGroupIndex,
        nlMatrixSDSourceAddress,     |    dsmonMatrixNLIndex,
        nlMatrixSDDestAddress        |    dsmonMatrixSourceAddress
        protocolDirLocalIndex        |    dsmonMatrixDestAddress
                                     |    dsmonMatrixALIndex
     alMatrixDSEntry                 | dsmonMatrixDSEntry
        hlMatrixControlIndex,        |    dsmonMatrixCtlIndex,
        alMatrixDSTimeMark,          |    dsmonMatrixTimeMark,
        protocolDirLocalIndex,       |    dsmonAggGroupIndex,
        nlMatrixDSDestAddress,       |    dsmonMatrixNLIndex,
        nlMatrixDSSourceAddress      |    dsmonMatrixDestAddress
        protocolDirLocalIndex        |    dsmonMatrixSourceAddress
                                     |    dsmonMatrixALIndex
    ---------------------------------+--------------------------------
                      Application Matrix TopN Distribution

                                     | dsmonMatrixTopNCtlEntry
                  none               |    dsmonMatrixTopNCtlIndex
                                     | dsmonMatrixTopNEntry
       (similar to nlMatrixTopN)     |    dsmonMatrixTopNCtlIndex,
                                     |    dsmonMatrixTopNIndex
    ---------------------------------+--------------------------------


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