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RFC 2021 - Remote Network Monitoring Management Information Base Version 2 using SMIv2



Network Working Group                                     S. Waldbusser
Request for Comments: 2021                                          INS
Category: Standards Track                                  January 1997

         Remote Network Monitoring Management Information Base
                               Version 2
                              using SMIv2

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.

Abstract

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in TCP/IP-based internets.
   In particular, it defines objects for managing remote network
   monitoring devices.

Table of Contents

1 The Network Management Framework ......................    2
2 Overview ..............................................    2
2.1 Remote Network Management Goals .....................    3
2.2 Structure of MIB ....................................    5
3 Control of Remote Network Monitoring Devices ..........    6
3.1 Resource Sharing Among  Multiple  Management  Sta-
     tions ..............................................    7
3.2 Row Addition Among Multiple Management Stations .....    9
4 Conventions ...........................................   10
5 RMON 2 Conventions ....................................   10
5.1 Usage of the term Application Level .................   10
5.2 Protocol Directory and Limited Extensibility ........   11
5.3 Errors in packets ...................................   11
6 Definitions ...........................................   12
7 Security Considerations ...............................  122
8 Appendix - TimeFilter Implementation Notes ...........   123
9 Acknowledgments ......................................   129
10 References ...........................................  129
11 Author's Address......................................  130

1.  The Network Management Framework

   The Internet-standard Network Management Framework consists of three
   components.  They are:

   RFC 1902 [1] which defines the SMI, the mechanisms used for
   describing and naming objects for the purpose of management.

   RFC 1213, STD 17, [3] which defines MIB-II, the core set of
   managed objects for the Internet suite of protocols.

   RFC 1905 [4] which defines the SNMP, the protocol used for
   network access to managed objects.

   The Framework permits new objects to be defined for the purpose of
   experimentation and evaluation.

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  Within a given MIB module,
   objects are defined using the SMI's OBJECT-TYPE macro.  At a minimum,
   each object has a name, a syntax, an access-level, and an
   implementation-status.

   The name is an object identifier, an administratively assigned name,
   which specifies an object type.  The object type together with an
   object instance serves to uniquely identify a specific instantiation
   of the object.  For human convenience, we often use a textual string,
   termed the object descriptor, to also refer to the object type.

   The syntax of an object type defines the abstract data structure
   corresponding to that object type.  The ASN.1 [6] language is used
   for this purpose.  However, RFC 1902 purposely restricts the ASN.1
   constructs which may be used.  These restrictions are explicitly made
   for simplicity.

   The access-level of an object type defines whether it makes "protocol
   sense" to read and/or write the value of an instance of the object
   type.  (This access-level is independent of any administrative
   authorization policy.)

   The implementation-status of an object type indicates whether the
   object is mandatory, optional, obsolete, or deprecated.

2.  Overview

   This document continues the architecture created in the RMON MIB [RFC
   1757] by providing a major feature upgrade, primarily by providing
   RMON analysis up to the application layer.

   Remote network monitoring devices, often called monitors or probes,
   are instruments that exist for the purpose of managing a network.
   Often these remote probes are stand-alone devices and devote
   significant internal resources for the sole purpose of managing a
   network.  An organization may employ many of these devices, one per
   network segment, to manage its internet.  In addition, these devices
   may be used for a network management service provider to access a
   client network, often geographically remote.

   The objects defined in this document are intended as an interface
   between an RMON agent and an RMON management application and are not
   intended for direct manipulation by humans.  While some users may
   tolerate the direct display of some of these objects, few will
   tolerate the complexity of manually manipulating objects to
   accomplish row creation.  These functions should be handled by the
   management application.

2.1.  Remote Network Management Goals

    o Offline Operation
        There are sometimes conditions when a management
        station will not be in constant contact with its
        remote monitoring devices.  This is sometimes by
        design in an attempt to lower communications costs
        (especially when communicating over a WAN or
        dialup link), or by accident as network failures
        affect the communications between the management
        station and the probe.

        For this reason, this MIB allows a probe to be
        configured to perform diagnostics and to collect
        statistics continuously, even when communication with
        the management station may not be possible or
        efficient.  The probe may then attempt to notify
        the management station when an exceptional condition
        occurs.  Thus, even in circumstances where
        communication between management station and probe is
        not continuous, fault, performance, and configuration
        information may be continuously accumulated and
        communicated to the management station conveniently
        and efficiently.

    o Proactive Monitoring
        Given the resources available on the monitor, it
        is potentially helpful for it continuously to run
        diagnostics and to log network performance.  The
        monitor is always available at the onset of any
        failure.  It can notify the management station of the
        failure and can store historical statistical
        information about the failure.  This historical
        information can be played back by the management
        station in an attempt to perform further diagnosis
        into the cause of the problem.

    o Problem Detection and Reporting
        The monitor can be configured to recognize
        conditions, most notably error conditions, and
        continuously to check for them.  When one of these
        conditions occurs, the event may be logged, and
        management stations may be notified in a number of
        ways.

    o Value Added Data
        Because a remote monitoring device represents a
        network resource dedicated exclusively to network
        management functions, and because it is located
        directly on the monitored portion of the network, the
        remote network monitoring device has the opportunity
        to add significant value to the data it collects.
        For instance, by highlighting those hosts on the
        network that generate the most traffic or errors, the
        probe can give the management station precisely the
        information it needs to solve a class of problems.

    o Multiple Managers
        An organization may have multiple management stations
        for different units of the organization, for different
        functions (e.g. engineering and operations), and in an
        attempt to provide disaster recovery.  Because
        environments with multiple management stations are
        common, the remote network monitoring device has to
        deal with more than own management station,
        potentially using its resources concurrently.

2.2.  Structure of MIB

   The objects are arranged into the following groups:

        - protocol directory

        - protocol distribution

        - address mapping

        - network layer host

        - network layer matrix

        - application layer host

        - application layer matrix

        - user history

        - probe configuration

   These groups are the basic units of conformance.  If a remote
   monitoring device implements a group, then it must implement all
   objects in that group.  For example, a managed agent that implements
   the network layer matrix group must implement the nlMatrixSDTable and
   the nlMatrixDSTable.

   Implementations of this MIB must also implement the system and
   interfaces group of MIB-II [3].  MIB-II may also mandate the
   implementation of additional groups.

   These groups are defined to provide a means of assigning object
   identifiers, and to provide a method for managed agents to know which
   objects they must implement.

   This document also contains enhancements to tables defined in the
   RMON MIB [RFC 1757].  These enhancements include:

    1) Adding the DroppedFrames and LastCreateTime
       conventions to each table defined in the RMON MIB.

    2) Augmenting the RMON filter table with a mechanism
       that allows filtering based on an offset from the
       beginning of a particular protocol, even if the
       protocol headers are variable length.

    3) Augmenting the RMON filter and capture status bits
       with additional bits for WAN media and generic media.
       These bits are defined here as:

        Bit     Definition
        6       For WAN media, this bit is set for packets
                coming from one direction and cleared for
                packets coming from the other direction.
                It is an implementation specific matter
                as to which bit is assigned to which
                direction, but it must be consistent for
                all packets received by the agent, and if
                the agent knows which end of the link is
                "local" and which end is "network", the bit
                should be set for packets from the "local"
                side and should be cleared for packets from
                the "network" side.

        7       For any media, this bit is set for any packet
                with a physical layer error. This bit may be
                set in addition to other media-specific bits
                that denote the same condition.

        8       For any media, this bit is set for any packet
                that is too short for the media. This bit may
                be set in addition to other media-specific
                bits that denote the same condition.
        9       For any media, this bit is set for any packet
                that is too long for the media. This bit may
                be set in addition to other media-specific bits
                that denote the same condition.

   These enhancements are implemented by RMON-2 probes that also
   implement RMON and do not add any requirements to probes that are
   compliant to just RMON.

3.  Control of Remote Network Monitoring Devices

   Due to the complex nature of the available functions in these
   devices, the functions often need user configuration.  In many cases,
   the function requires parameters to be set up for a data collection
   operation.  The operation can proceed only after these parameters are
   fully set up.

   Many functional groups in this MIB have one or more tables in which
   to set up control parameters, and one or more data tables in which to
   place the results of the operation.  The control tables are typically
   read/write in nature, while the data tables are typically read/only.

   Because the parameters in the control table often describe resulting
   data in the data table, many of the parameters can be modified only
   when the control entry is not active.  Thus, the method for modifying
   these parameters is to de-activate the entry, perform the SNMP Set
   operations to modify the entry, and then re-activate the entry.
   Deleting the control entry causes the deletion of any associated data
   entries, which also gives a convenient method for reclaiming the
   resources used by the associated data.

   Some objects in this MIB provide a mechanism to execute an action on
   the remote monitoring device.  These objects may execute an action as
   a result of a change in the state of the object.  For those objects
   in this MIB, a request to set an object to the same value as it
   currently holds would thus cause no action to occur.

   To facilitate control by multiple managers, resources have to be
   shared among the managers.  These resources are typically the memory
   and computation resources that a function requires.

3.1.  Resource Sharing Among Multiple Management Stations

   When multiple management stations wish to use functions that compete
   for a finite amount of resources on a device, a method to facilitate
   this sharing of resources is required.  Potential conflicts include:

    o Two management stations wish to simultaneously use
      resources that together would exceed the capability of
      the device.
    o A management station uses a significant amount of
      resources for a long period of time.
    o A management station uses resources and then crashes,
      forgetting to free the resources so others may
      use them.

   The OwnerString mechanism is provided for each management station
   initiated function in this MIB to avoid these conflicts and to help
   resolve them when they occur.  Each function has a label identifying
   the initiator (owner) of the function.  This label is set by the
   initiator to provide for the following possibilities:

    o A management station may recognize resources it owns
      and no longer needs.
    o A network operator can find the management station that
      owns the resource and negotiate for it to be freed.
    o A network operator may decide to unilaterally free
      resources another network operator has reserved.

    o Upon initialization, a management station may recognize
      resources it had reserved in the past.  With this
      information it may free the resources if it no longer
      needs them.

   Management stations and probes should support any format of the owner
   string dictated by the local policy of the organization.  It is
   suggested that this name contain one or more of the following: IP
   address, management station name, network manager's name, location,
   or phone number.  This information will help users to share the
   resources more effectively.

   There is often default functionality that the device or the
   administrator of the probe (often the network administrator) wishes
   to set up.  The resources associated with this functionality are then
   owned by the device itself or by the network administrator, and are
   intended to be long-lived.  In this case, the device or the
   administrator will set the relevant owner object to a string starting
   with 'monitor'.  Indiscriminate modification of the monitor-owned
   configuration by network management stations is discouraged.  In
   fact, a network management station should only modify these objects
   under the direction of the administrator of the probe.

   Resources on a probe are scarce and are typically allocated when
   control rows are created by an application.  Since many applications
   may be using a probe simultaneously, indiscriminate allocation of
   resources to particular applications is very likely to cause resource
   shortages in the probe.

   When a network management station wishes to utilize a function in a
   monitor, it is encouraged to first scan the control table of that
   function to find an instance with similar parameters to share.  This
   is especially true for those instances owned by the monitor, which
   can be assumed to change infrequently.  If a management station
   decides to share an instance owned by another management station, it
   should understand that the management station that owns the instance
   may indiscriminately modify or delete it.

   It should be noted that a management application should have the most
   trust in a monitor-owned row because it should be changed very
   infrequently.  A row owned by the management application is less
   long-lived because a network administrator is more likely to re-
   assign resources from a row that is in use by one user than from a
   monitor-owned row that is potentially in use by many users.  A row
   owned by another application would be even less long-lived because
   the other application may delete or modify that row completely at its
   discretion.

3.2.  Row Addition Among Multiple Management Stations

   The addition of new rows is achieved using the RowStatus method
   described in RFC 1903 [2].  In this MIB, rows are often added to a
   table in order to configure a function.  This configuration usually
   involves parameters that control the operation of the function.  The
   agent must check these parameters to make sure they are appropriate
   given restrictions defined in this MIB as well as any implementation
   specific restrictions such as lack of resources.  The agent
   implementor may be confused as to when to check these parameters and
   when to signal to the management station that the parameters are
   invalid.  There are two opportunities:

    o When the management station sets each parameter object.

    o When the management station sets the row status object
      to active.

   If the latter is chosen, it would be unclear to the management
   station which of the several parameters was invalid and caused the
   badValue error to be emitted.  Thus, wherever possible, the
   implementor should choose the former as it will provide more
   information to the management station.

   A problem can arise when multiple management stations attempt to set
   configuration information simultaneously using SNMP.  When this
   involves the addition of a new conceptual row in the same control
   table, the managers may collide, attempting to create the same entry.
   To guard against these collisions, each such control entry contains a
   status object with special semantics that help to arbitrate among the
   managers.  If an attempt is made with the row addition mechanism to
   create such a status object and that object already exists, an error
   is returned.  When more than one manager simultaneously attempts to
   create the same conceptual row, only the first will succeed.  The
   others will receive an error.

   In the RMON MIB [RFC 1757], the EntryStatus textual convention was
   introduced to provide this mutual exclusion function.  Since then,
   this function was added to the SNMP framework as the RowStatus
   textual convention.  The RowStatus textual convention is used for the
   definition of all new tables.

   When a manager wishes to create a new control entry, it needs to
   choose an index for that row.  It may choose this index in a variety
   of ways, hopefully minimizing the chances that the index is in use by
   another manager.  If the index is in use, the mechanism mentioned
   previously will guard against collisions.  Examples of schemes to
   choose index values include random selection or scanning the control

   table looking for the first unused index.  Because index values may
   be any valid value in the range and they are chosen by the manager,
   the agent must allow a row to be created with any unused index value
   if it has the resources to create a new row.

   Some tables in this MIB reference other tables within this MIB.  When
   creating or deleting entries in these tables, it is generally
   allowable for dangling references to exist.  There is no defined
   order for creating or deleting entries in these tables.

4.  Conventions

   The following conventions are used throughout the RMON MIB and its
   companion documents.

   Good Packets

   Good packets are error-free packets that have a valid frame length.
   For example, on Ethernet, good packets are error-free packets that
   are between 64 octets long and 1518 octets long.  They follow the
   form defined in IEEE 802.3 section 3.2.all.

   Bad Packets

   Bad packets are packets that have proper framing and are therefore
   recognized as packets, but contain errors within the packet or have
   an invalid length.  For example, on Ethernet, bad packets have a
   valid preamble and SFD, but have a bad CRC, or are either shorter
   than 64 octets or longer than 1518 octets.

5.  RMON 2 Conventions

   The following practices and conventions are introduced in the RMON 2
   MIB.

5.1.  Usage of the term Application Level

   There are many cases in this MIB where the term Application Level is
   used to describe a class of protocols or a capability.  This does not
   typically mean a protocol that is an OSI Layer 7 protocol.  Rather,
   it is used to identify a class of protocols that is not limited to
   MAC-layer and network-layer protocols, but can also include
   transport, session, presentation, and application-layer protocols.

5.2.  Protocol Directory and Limited Extensibility

   Every RMON 2 implementation will have the capability to parse certain
   types of packets and identify their protocol type at multiple levels,
   The protocol directory presents an inventory of those protocol types
   the probe is capable of monitoring, and allows the addition,
   deletion, and configuration of protocol types in this list.

   One concept deserves special attention: the "limited extensibility"
   of the protocol directory table.  The RMON 2 model is that protocols
   are detected by static software that has been written at
   implementation time.  Therefore, as a matter of configuration, an
   implementation does not have the ability to suddenly learn how to
   parse new packet types.  However, an implementation may be written
   such that the software knows where the demultiplexing field is for a
   particular protocol, and can be written in such a way that the
   decoding of the next layer up is table-driven.  This works when the
   code has been written to accomodate it and can be extended no more
   than one level higher.  This extensibility is called "limited
   extensibility" to highlight these limitations.  However, this can be
   a very useful tool.

   For example, suppose that an implementation has C code that
   understands how to decode IP packets on any of several ethernet
   encapsulations, and also knows how to interpret the IP protocol field
   to recognize UDP packets and how to decode the UDP port number
   fields.  That implementation may be table- driven so that among the
   many different UDP port numbers possible, it is configured to
   recognize 161 as SNMP, port 53 as DNS, and port 69 as TFTP.  The
   limited extensibility of the protocol directory table would allow an
   SNMP operation to create an entry that would create an additional
   table mapping for UDP that would recognize UDP port 123 as NTP and
   begin counting such packets.

   This limited extensibility is an option that an implementation can
   choose to allow or disallow for any protocol that has child
   protocols.

5.3.  Errors in packets

   Packets with link-level errors are not counted anywhere in this MIB
   because most variables in this MIB requires the decoding of the
   contents of the packet, which is meaningless if there is a link-level
   error.

   Packets in which protocol errors are detected are counted for all
   protocols below the layer in which the error was encountered.  The
   implication of this is that packets in which errors are detected at

   the network-layer are not counted anywhere in this MIB, while packets
   with errors detected at the transport layer may have network-layer
   statistics counted.

6.  Definitions

RMON2-MIB DEFINITIONS ::= BEGIN
IMPORTS
    MODULE-IDENTITY, OBJECT-TYPE, Counter32, Integer32,
        Gauge32, IpAddress, TimeTicks            FROM SNMPv2-SMI
    TEXTUAL-CONVENTION, RowStatus, DisplayString, TimeStamp
                                                 FROM SNMPv2-TC
    MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF
    mib-2, ifIndex                  FROM RFC1213-MIB
    OwnerString, statistics, history, hosts,
    matrix, filter, etherStatsEntry, historyControlEntry,
    hostControlEntry, matrixControlEntry, filterEntry,
    channelEntry                    FROM RMON-MIB
    tokenRing, tokenRingMLStatsEntry, tokenRingPStatsEntry,
    ringStationControlEntry, sourceRoutingStatsEntry
                                    FROM TOKEN-RING-RMON-MIB;
--  Remote Network Monitoring MIB

rmon MODULE-IDENTITY
    LAST-UPDATED "9605270000Z"
    ORGANIZATION "IETF RMON MIB Working Group"
    CONTACT-INFO
        "Steve Waldbusser   (WG Editor)
         Postal: International Network Services
         650 Castro Street, Suite 260
         Mountain View, CA 94041
         Phone:  +1 415 254 4251
         Email:  waldbusser@ins.com

         Andy Bierman   (WG Chair)
         Phone:  +1 805 648 2028
         Email:  abierman@west.net"
    DESCRIPTION
        "The MIB module for managing remote monitoring
         device implementations. This MIB module
         augments the original RMON MIB as specified in
         RFC 1757."
    ::= { mib-2 16 }

-- { rmon 1 } through { rmon 10 } are defined in RMON and
-- the Token Ring RMON MIB [RFC 1513]

    protocolDir     OBJECT IDENTIFIER ::= { rmon 11 }
    protocolDist    OBJECT IDENTIFIER ::= { rmon 12 }
    addressMap      OBJECT IDENTIFIER ::= { rmon 13 }
    nlHost          OBJECT IDENTIFIER ::= { rmon 14 }
    nlMatrix        OBJECT IDENTIFIER ::= { rmon 15 }
    alHost          OBJECT IDENTIFIER ::= { rmon 16 }
    alMatrix        OBJECT IDENTIFIER ::= { rmon 17 }
    usrHistory      OBJECT IDENTIFIER ::= { rmon 18 }
    probeConfig     OBJECT IDENTIFIER ::= { rmon 19 }
    rmonConformance OBJECT IDENTIFIER ::= { rmon 20 }

-- Textual Conventions

ZeroBasedCounter32 ::= TEXTUAL-CONVENTION
    STATUS current
    DESCRIPTION
        "This TC describes an object which counts events with the
        following semantics: objects of this type will be set to
        zero(0) on creation and will thereafter count appropriate
        events, wrapping back to zero(0) when the value 2^32 is
        reached.

        Provided that an application discovers the new object within
        the minimum time to wrap it can use the initial value as a
        delta since it last polled the table of which this object is
        part.  It is important for a management station to be aware of
        this minimum time and the actual time between polls, and to
        discard data if the actual time is too long or there is no
        defined minimum time.

        Typically this TC is used in tables where the INDEX space is
        constantly changing and/or the TimeFilter mechanism is in use."
    SYNTAX Gauge32

LastCreateTime ::= TEXTUAL-CONVENTION
    STATUS current
    DESCRIPTION
        "This TC describes an object that stores the last time its
        entry was created.

        This can be used for polling applications to determine that an
        entry has been deleted and re-created between polls, causing
        an otherwise undetectable discontinuity in the data."
    SYNTAX TimeStamp

TimeFilter ::= TEXTUAL-CONVENTION
    STATUS        current
    DESCRIPTION

        "To be used for the index to a table.  Allows an application
        to download only those rows changed since a particular time.
        A row is considered changed if the value of any object in the
        row changes or if the row is created or deleted.

        When sysUpTime is equal to zero, this table shall be empty.

        One entry exists for each past value of sysUpTime, except that
        the whole table is purged should sysUpTime wrap.

        As this basic row is updated new conceptual rows are created
        (which still share the now updated object values with all
        other instances).  The number of instances which are created
        is determined by the value of sysUpTime at which the basic row
        was last updated.  One instance will exist for each value of
        sysUpTime at the last update time for the row.  A new
        timeMark instance is created for each new sysUpTime value.
        Each new conceptual row will be associated with the timeMark
        instance which was created at the value of sysUpTime with
        which the conceptual row is to be associated.

        By definition all conceptual rows were updated at or after
        time zero and so at least one conceptual row (associated with
        timeMark.0) must exist for each underlying (basic) row.

        See the appendix for further discussion of this variable.

        Consider the following fooTable:

        fooTable ...
        INDEX { fooTimeMark, fooIndex }

        FooEntry {
           fooTimeMark  TimeFilter
           fooIndex     INTEGER,
           fooCounts    Counter
        }

        Should there be two basic rows in this table (fooIndex == 1,
        fooIndex == 2) and row 1 was updated most recently at time 6,
        while row 2 was updated most recently at time 8, and both rows
        had been updated on several earlier occasions such that the
        current values were 5 and 9 respectively then the following
        fooCounts instances would exist.

        fooCounts.0.1  5
        fooCounts.0.2  9
        fooCounts.1.1  5

        fooCounts.1.2  9
        fooCounts.2.1  5
        fooCounts.2.2  9
        fooCounts.3.1  5
        fooCounts.3.2  9
        fooCounts.4.1  5
        fooCounts.4.2  9
        fooCounts.5.1  5
        fooCounts.5.2  9
        fooCounts.6.1  5
        fooCounts.6.2  9
        fooCounts.7.2  9    -- note that row 1 doesn't exist for
        fooCounts.8.2  9    -- times 7 and 8"
    SYNTAX    TimeTicks

DataSource ::= TEXTUAL-CONVENTION
    STATUS        current
    DESCRIPTION
        "Identifies the source of the data that the associated
        function is configured to analyze. This source can be any
        interface on this device.

        In order to identify a particular interface, this
        object shall identify the instance of the ifIndex
        object, defined in [3,5], for the desired interface.

        For example, if an entry were to receive data from
        interface #1, this object would be set to ifIndex.1."
    SYNTAX      OBJECT IDENTIFIER
--
-- Protocol Directory Group
--
-- Lists the inventory of protocols the probe has the capability of
-- monitoring and allows the addition, deletion, and configuration of
-- entries in this list.

protocolDirLastChange OBJECT-TYPE
    SYNTAX      TimeStamp
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The value of sysUpTime at the time the protocol directory
        was last modified, either through insertions or deletions,
        or through modifications of either the
        protocolDirAddressMapConfig, protocolDirHostConfig, or
        protocolDirMatrixConfig."
    ::= { protocolDir 1 }

protocolDirTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF ProtocolDirEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "This table lists the protocols that this agent has the
        capability to decode and count.  There is one entry in this
        table for each such protocol.  These protocols represent
        different network layer, transport layer, and higher-layer
        protocols.  The agent should boot up with this table
        preconfigured with those protocols that it knows about and
        wishes to monitor.  Implementations are strongly encouraged to
        support protocols higher than the network layer (at least for
        the protocol distribution group), even for implementations
        that don't support the application layer groups."
    ::= { protocolDir 2 }

protocolDirEntry OBJECT-TYPE
    SYNTAX      ProtocolDirEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the protocolDirTable.

         An example of the indexing of this entry is
         protocolDirLocalIndex.8.0.0.0.1.0.0.8.0.2.0.0, which is the
         encoding of a length of 8, followed by 8 subids encoding the
         protocolDirID of 1.2048, followed by a length of 2 and the
         2 subids encoding zero-valued parameters."
    INDEX { protocolDirID, protocolDirParameters }
    ::= { protocolDirTable  1 }

ProtocolDirEntry ::= SEQUENCE {
    protocolDirID                   OCTET STRING,
    protocolDirParameters           OCTET STRING,
    protocolDirLocalIndex           Integer32,
    protocolDirDescr                DisplayString,
    protocolDirType                 BITS,
    protocolDirAddressMapConfig     INTEGER,
    protocolDirHostConfig           INTEGER,
    protocolDirMatrixConfig         INTEGER,
    protocolDirOwner                OwnerString,
    protocolDirStatus               RowStatus
}

protocolDirID OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible

    STATUS      current
    DESCRIPTION
        "A unique identifier for a particular protocol.  Standard
        identifiers will be defined in a manner such that they
        can often be used as specifications for new protocols - i.e.
        a tree-structured assignment mechanism that matches the
        protocol encapsulation `tree' and which has algorithmic
        assignment mechanisms for certain subtrees. See RFC XXX for
        more details.

        Despite the algorithmic mechanism, the probe will only place
        entries in here for those protocols it chooses to collect.  In
        other words, it need not populate this table with all of the
        possible ethernet protocol types, nor need it create them on
        the fly when it sees them.  Whether or not it does these
        things is a matter of product definition (cost/benefit,
        usability), and is up to the designer of the product.

        If an entry is written to this table with a protocolDirID that
        the agent doesn't understand, either directly or
        algorithmically, the SET request will be rejected with an
        inconsistentName or badValue (for SNMPv1) error."
    ::= { protocolDirEntry 1 }

protocolDirParameters OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A set of parameters for the associated protocolDirID.
        See the associated RMON2 Protocol Identifiers document
        for a description of the possible parameters. There
        will be one octet in this string for each sub-identifier in
        the protocolDirID, and the parameters will appear here in the
        same order as the associated sub-identifiers appear in the
        protocolDirID.

        Every node in the protocolDirID tree has a different, optional
        set of parameters defined (that is, the definition of
        parameters for a node is optional).  The proper parameter
        value for each node is included in this string.  Note that the
        inclusion of a parameter value in this string for each node is
        not optional - what is optional is that a node may have no
        parameters defined, in which case the parameter field for that
        node will be zero."
    ::= { protocolDirEntry 2 }

protocolDirLocalIndex OBJECT-TYPE

    SYNTAX      Integer32 (1..2147483647)
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The locally arbitrary, but unique identifier associated
        with this protocolDir entry.

        The value for each supported protocol must remain constant at
        least from one re-initialization of the entity's network
        management system to the next re-initialization, except that
        if a protocol is deleted and re-created, it must be re-created
        with a new value that has not been used since the last
        re-initialization.

        The specific value is meaningful only within a given SNMP
        entity. A protocolDirLocalIndex must not be re-used until the
        next agent-restart in the event the protocol directory entry
        is deleted."
    ::= { protocolDirEntry 3 }

protocolDirDescr OBJECT-TYPE
    SYNTAX      DisplayString (SIZE (1..64))
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "A textual description of the protocol encapsulation.
        A probe may choose to describe only a subset of the
        entire encapsulation (e.g. only the highest layer).

        This object is intended for human consumption only.

        This object may not be modified if the associated
        protocolDirStatus object is equal to active(1)."
    ::= { protocolDirEntry 4 }

protocolDirType OBJECT-TYPE
    SYNTAX      BITS {
                    extensible(0),
                    addressRecognitionCapable(1)
                }
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "This object describes 2 attributes of this protocol
         directory entry.

         The presence or absence of the `extensible' bit describes
         whether or not this protocol directory entry can be extended

         by the user by creating protocol directory entries which are
         children of this protocol.

         An example of an entry that will often allow extensibility is
         `ip.udp'.  The probe may automatically populate some children
         of this node such as `ip.udp.snmp' and `ip.udp.dns'.
         A probe administrator or user may also populate additional
         children via remote SNMP requests that create entries in this
         table.  When a child node is added for a protocol for which the
         probe has no built in support, extending a parent node (for
         which the probe does have built in support),
         that child node is not extendible.  This is termed `limited
         extensibility'.

         When a child node is added through this extensibility
         mechanism, the values of protocolDirLocalIndex and
         protocolDirType shall be assigned by the agent.

         The other objects in the entry will be assigned by the
         manager who is creating the new entry.

         This object also describes whether or not this agent can
         recognize addresses for this protocol, should it be a network
         level protocol.  That is, while a probe may be able to
         recognize packets of a particular network layer protocol and
         count them, it takes additional logic to be able to recognize
         the addresses in this protocol and to populate network layer
         or application layer tables with the addresses in this
         protocol.  If this bit is set, the agent will recognize
         network layer addresses for this protoocl and populate the
         network and application layer host and matrix tables with
         these protocols.

         Note that when an entry is created, the agent will supply
         values for the bits that match the capabilities of the agent
         with respect to this protocol.  Note that since row creations
         usually exercise the limited extensibility feature, these
         bits will usually be set to zero."
    ::= { protocolDirEntry 5 }

protocolDirAddressMapConfig OBJECT-TYPE
    SYNTAX      INTEGER {
                    notSupported(1),
                    supportedOff(2),
                    supportedOn(3)
                }
    MAX-ACCESS  read-create
    STATUS      current

    DESCRIPTION
        "This object describes and configures the probe's support for
        address mapping for this protocol.  When the probe creates
        entries in this table for all protocols that it understands,
        it will set the entry to notSupported(1) if it doesn't have
        the capability to perform address mapping for the protocol or
        if this protocol is not a network-layer protocol.  When
        an entry is created in this table by a management operation as
        part of the limited extensibility feature, the probe must set
        this value to notSupported(1), because limited extensibility
        of the protocolDirTable does not extend to interpreting
        addresses of the extended protocols.

        If the value of this object is notSupported(1), the probe
        will not perform address mapping for this protocol and
        shall not allow this object to be changed to any other value.
        If the value of this object is supportedOn(3), the probe
        supports address mapping for this protocol and is configured
        to perform address mapping for this protocol for all
        addressMappingControlEntries and all interfaces.
        If the value of this object is supportedOff(2), the probe
        supports address mapping for this protocol but is configured
        to not perform address mapping for this protocol for any
        addressMappingControlEntries and all interfaces.
        Whenever this value changes from supportedOn(3) to
        supportedOff(2), the probe shall delete all related entries in
        the addressMappingTable."
    ::= { protocolDirEntry 6 }

protocolDirHostConfig OBJECT-TYPE
    SYNTAX      INTEGER {
                    notSupported(1),
                    supportedOff(2),
                    supportedOn(3)
                }
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "This object describes and configures the probe's support for
        the network layer and application layer host tables for this
        protocol.  When the probe creates entries in this table for
        all protocols that it understands, it will set the entry to
        notSupported(1) if it doesn't have the capability to track the
        nlHostTable for this protocol or if the alHostTable is
        implemented but doesn't have the capability to track this
        protocol.  Note that if the alHostTable is implemented, the
        probe may only support a protocol if it is supported in both
        the nlHostTable and the alHostTable.

        If the associated protocolDirType object has the
        addressRecognitionCapable bit set, then this is a network
        layer protocol for which the probe recognizes addresses, and
        thus the probe will populate the nlHostTable and alHostTable
        with addresses it discovers for this protocol.

        If the value of this object is notSupported(1), the probe
        will not track the nlHostTable or alHostTable for this
        protocol and shall not allow this object to be changed to any
        other value. If the value of this object is supportedOn(3),
        the probe supports tracking of the nlHostTable and alHostTable
        for this protocol and is configured to track both tables
        for this protocol for all control entries and all interfaces.
        If the value of this object is supportedOff(2), the probe
        supports tracking of the nlHostTable and alHostTable for this
        protocol but is configured to not track these tables
        for any control entries or interfaces.
        Whenever this value changes from supportedOn(3) to
        supportedOff(2), the probe shall delete all related entries in
        the nlHostTable and alHostTable.

        Note that since each alHostEntry references 2 protocol
        directory entries, one for the network address and one for the
        type of the highest protocol recognized, that an entry will
        only be created in that table if this value is supportedOn(3)
        for both protocols."
    ::= { protocolDirEntry 7 }

protocolDirMatrixConfig OBJECT-TYPE
    SYNTAX      INTEGER {
                    notSupported(1),
                    supportedOff(2),
                    supportedOn(3)
                }
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "This object describes and configures the probe's support for
        the network layer and application layer matrix tables for this
        protocol.  When the probe creates entries in this table for
        all protocols that it understands, it will set the entry to
        notSupported(1) if it doesn't have the capability to track the
        nlMatrixTables for this protocol or if the alMatrixTables are
        implemented but don't have the capability to track this
        protocol.  Note that if the alMatrix tables are implemented,
        the probe may only support a protocol if it is supported in
        the the both of the nlMatrixTables and both of the
        alMatrixTables.

        If the associated protocolDirType object has the
        addressRecognitionCapable bit set, then this is a network
        layer protocol for which the probe recognizes addresses, and
        thus the probe will populate both of the nlMatrixTables and
        both of the alMatrixTables with addresses it discovers for
        this protocol.

        If the value of this object is notSupported(1), the probe
        will not track either of the nlMatrixTables or the
        alMatrixTables for this protocol and shall not allow this
        object to be changed to any other value. If the value of this
        object is supportedOn(3), the probe supports tracking of both
        of the nlMatrixTables and (if implemented) both of the
        alMatrixTables for this protocol and is configured to track
        these tables for this protocol for all control entries and all
        interfaces. If the value of this object is supportedOff(2),
        the probe supports tracking of both of the nlMatrixTables and
        (if implemented) both of the alMatrixTables for this protocol
        but is configured to not track these tables for this
        protocol for any control entries or interfaces.
        Whenever this value changes from supportedOn(3) to
        supportedOff(2), the probe shall delete all related entries in
        the nlMatrixTables and the alMatrixTables.

        Note that since each alMatrixEntry references 2 protocol
        directory entries, one for the network address and one for the
        type of the highest protocol recognized, that an entry will
        only be created in that table if this value is supportedOn(3)
        for both protocols."
    ::= { protocolDirEntry 8 }

protocolDirOwner OBJECT-TYPE
    SYNTAX      OwnerString
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The entity that configured this entry and is
        therefore using the resources assigned to it."
    ::= { protocolDirEntry 9 }

protocolDirStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The status of this protocol directory entry.

        An entry may not exist in the active state unless all

        objects in the entry have an appropriate value.

        If this object is not equal to active(1), all associated
        entries in the nlHostTable, nlMatrixSDTable, nlMatrixDSTable,
        alHostTable, alMatrixSDTable, and alMatrixDSTable shall be
        deleted."
    ::= { protocolDirEntry 10 }

--
-- Protocol Distribution Group  (protocolDist)
--
-- Collects the relative amounts of octets and packets for the
-- different protocols detected on a network segment.
--    protocolDistControlTable,
--    protocolDistStatsTable

protocolDistControlTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF ProtocolDistControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "Controls the setup of protocol type distribution statistics
        tables.

        Implementations are encouraged to add an entry per monitored
        interface upon initialization so that a default collection
        of protocol statistics is available.

        Rationale:
        This table controls collection of very basic statistics
        for any or all of the protocols detected on a given interface.
        An NMS can use this table to quickly determine bandwidth
        allocation utilized by different protocols.

        A media-specific statistics collection could also
        be configured (e.g. etherStats, trPStats) to easily obtain
        total frame, octet, and droppedEvents for the same
        interface."
    ::= { protocolDist 1 }

protocolDistControlEntry OBJECT-TYPE
    SYNTAX      ProtocolDistControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the protocolDistControlTable.

         An example of the indexing of this entry is

         protocolDistControlDroppedFrames.7"
    INDEX { protocolDistControlIndex }
    ::= { protocolDistControlTable 1 }

ProtocolDistControlEntry ::= SEQUENCE {
    protocolDistControlIndex                Integer32,
    protocolDistControlDataSource           DataSource,
    protocolDistControlDroppedFrames        Counter32,
    protocolDistControlCreateTime           LastCreateTime,
    protocolDistControlOwner                OwnerString,
    protocolDistControlStatus               RowStatus
}

protocolDistControlIndex OBJECT-TYPE
    SYNTAX      Integer32 (1..65535)
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A unique index for this protocolDistControlEntry."
    ::= { protocolDistControlEntry 1 }

protocolDistControlDataSource OBJECT-TYPE
    SYNTAX      DataSource
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The source of data for the this protocol distribution.

        The statistics in this group reflect all packets
        on the local network segment attached to the
        identified interface.

        This object may not be modified if the associated
        protocolDistControlStatus object is equal to active(1)."
    ::= { protocolDistControlEntry 2 }

protocolDistControlDroppedFrames OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
       "The total number of frames which were received by the probe
        and therefore not accounted for in the *StatsDropEvents, but
        for which the probe chose not to count for this entry for
        whatever reason.  Most often, this event occurs when the probe
        is out of some resources and decides to shed load from this
        collection.

        This count does not include packets that were not counted
        because they had MAC-layer errors.

        Note that, unlike the dropEvents counter, this number is the
        exact number of frames dropped."
    ::= { protocolDistControlEntry 3 }

protocolDistControlCreateTime OBJECT-TYPE
    SYNTAX     LastCreateTime
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The value of sysUpTime when this control entry was last
        activated. This can be used by the management station to
        ensure that the table has not been deleted and recreated
        between polls."
    ::= { protocolDistControlEntry 4 }

protocolDistControlOwner OBJECT-TYPE
    SYNTAX      OwnerString
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The entity that configured this entry and is
        therefore using the resources assigned to it."
    ::= { protocolDistControlEntry 5 }

protocolDistControlStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The status of this row.

        An entry may not exist in the active state unless all
        objects in the entry have an appropriate value.

        If this object is not equal to active(1), all associated
        entries in the protocolDistStatsTable shall be deleted."
    ::= { protocolDistControlEntry 6 }

-- per interface protocol distribution statistics table
protocolDistStatsTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF ProtocolDistStatsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "An entry is made in this table for every protocol in the

        protocolDirTable which has been seen in at least one packet.
        Counters are updated in this table for every protocol type
        that is encountered when parsing a packet, but no counters are
        updated for packets with MAC-layer errors.

        Note that if a protocolDirEntry is deleted, all associated
        entries in this table are removed."
    ::= { protocolDist 2 }

protocolDistStatsEntry OBJECT-TYPE
    SYNTAX      ProtocolDistStatsEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the protocolDistStatsTable.

        The index is composed of the protocolDistControlIndex of the
        associated protocolDistControlEntry followed by the
        protocolDirLocalIndex of the associated protocol that this
        entry represents.  In other words, the index identifies the
        protocol distribution an entry is a part of as well as the
        particular protocol that it represents.

        An example of the indexing of this entry is
        protocolDistStatsPkts.1.18"
    INDEX { protocolDistControlIndex, protocolDirLocalIndex }
    ::= { protocolDistStatsTable 1 }

ProtocolDistStatsEntry ::= SEQUENCE {
    protocolDistStatsPkts                    ZeroBasedCounter32,
    protocolDistStatsOctets                  ZeroBasedCounter32
}

protocolDistStatsPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets without errors received of this
        protocol type.  Note that this is the number of link-layer
        packets, so if a single network-layer packet is fragmented
        into several link-layer frames, this counter is incremented
        several times."
    ::= { protocolDistStatsEntry 1 }

protocolDistStatsOctets OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only

    STATUS      current
    DESCRIPTION
        "The number of octets in packets received of this protocol
        type since it was added to the protocolDistStatsTable
        (excluding framing bits but including FCS octets), except for
        those octets in packets that contained errors.

        Note this doesn't count just those octets in the particular
        protocol frames, but includes the entire packet that contained
        the protocol."
    ::= { protocolDistStatsEntry 2 }

--
-- Address Map Group   (addressMap)
--
-- Lists MAC address to network address bindings discovered by the
-- probe and what interface they were last seen on.
--    addressMapControlTable
--    addressMapTable

addressMapInserts OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an address mapping entry has been
        inserted into the addressMapTable.  If an entry is inserted,
        then deleted, and then inserted, this counter will be
        incremented by 2.

        Note that the table size can be determined by subtracting
        addressMapDeletes from addressMapInserts."
    ::= { addressMap 1 }

addressMapDeletes OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an address mapping entry has been
        deleted from the addressMapTable (for any reason).  If
        an entry is deleted, then inserted, and then deleted, this
        counter will be incremented by 2.

        Note that the table size can be determined by subtracting
        addressMapDeletes from addressMapInserts."
    ::= { addressMap 2 }

addressMapMaxDesiredEntries OBJECT-TYPE
    SYNTAX      Integer32 (-1..2147483647)
    MAX-ACCESS  read-write
    STATUS      current
    DESCRIPTION
        "The maximum number of entries that are desired in the
        addressMapTable. The probe will not create more than
        this number of entries in the table, but may choose to create
        fewer entries in this table for any reason including the lack
        of resources.

        If this object is set to a value less than the current number
        of entries, enough entries are chosen in an
        implementation-dependent manner and deleted so that the number
        of entries in the table equals the value of this object.

        If this value is set to -1, the probe may create any number
        of entries in this table.

        This object may be used to control how resources are allocated
        on the probe for the various RMON functions."
    ::= { addressMap 3 }

addressMapControlTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF AddressMapControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A table to control the collection of network layer address to
        physical address to interface mappings.

        Note that this is not like the typical RMON
        controlTable and dataTable in which each entry creates
        its own data table.  Each entry in this table enables the
        discovery of addresses on a new interface and the placement
        of address mappings into the central addressMapTable.

        Implementations are encouraged to add an entry per monitored
        interface upon initialization so that a default collection
        of address mappings is available."
    ::= { addressMap 4 }

addressMapControlEntry OBJECT-TYPE
    SYNTAX      AddressMapControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the addressMapControlTable.

        An example of the indexing of this entry is
        addressMapControlDroppedFrames.1"
    INDEX { addressMapControlIndex }
    ::= { addressMapControlTable 1 }

AddressMapControlEntry ::= SEQUENCE {
    addressMapControlIndex              Integer32,
    addressMapControlDataSource         DataSource,
    addressMapControlDroppedFrames      Counter32,
    addressMapControlOwner              OwnerString,
    addressMapControlStatus             RowStatus
}

addressMapControlIndex OBJECT-TYPE
    SYNTAX      Integer32 (1..65535)
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A unique index for this entry in the addressMapControlTable."
    ::= { addressMapControlEntry 1 }

addressMapControlDataSource OBJECT-TYPE
    SYNTAX      DataSource
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The source of data for this addressMapControlEntry."
    ::= { addressMapControlEntry 2 }

addressMapControlDroppedFrames OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
       "The total number of frames which were received by the probe
        and therefore not accounted for in the *StatsDropEvents, but
        for which the probe chose not to count for this entry for
        whatever reason.  Most often, this event occurs when the probe
        is out of some resources and decides to shed load from this
        collection.

        This count does not include packets that were not counted
        because they had MAC-layer errors.

        Note that, unlike the dropEvents counter, this number is the
        exact number of frames dropped."
    ::= { addressMapControlEntry 3 }

addressMapControlOwner OBJECT-TYPE
    SYNTAX      OwnerString
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The entity that configured this entry and is
        therefore using the resources assigned to it."
    ::= { addressMapControlEntry 4 }

addressMapControlStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The status of this addressMap control entry.

        An entry may not exist in the active state unless all
        objects in the entry have an appropriate value.

        If this object is not equal to active(1), all associated
        entries in the addressMapTable shall be deleted."
    ::= { addressMapControlEntry 5 }

addressMapTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF AddressMapEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A table of network layer address to physical address to
        interface mappings.

        The probe will add entries to this table based on the source
        MAC and network addresses seen in packets without MAC-level
        errors. The probe will populate this table for all protocols
        in the protocol directory table whose value of
        protocolDirAddressMapConfig is equal to supportedOn(3), and
        will delete any entries whose protocolDirEntry is deleted or
        has a protocolDirAddressMapConfig value of supportedOff(2)."
    ::= { addressMap 5 }

addressMapEntry OBJECT-TYPE
    SYNTAX      AddressMapEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the addressMapTable.
        The protocolDirLocalIndex in the index identifies the network
        layer protocol of the addressMapNetworkAddress.

        An example of the indexing of this entry is
        addressMapSource.783495.18.4.128.2.6.6.11.1.3.6.1.2.1.2.2.1.1.1"
    INDEX { addressMapTimeMark, protocolDirLocalIndex,
            addressMapNetworkAddress, addressMapSource }
    ::= { addressMapTable 1 }

AddressMapEntry ::= SEQUENCE {
    addressMapTimeMark                 TimeFilter,
    addressMapNetworkAddress           OCTET STRING,
    addressMapSource                   OBJECT IDENTIFIER,
    addressMapPhysicalAddress          OCTET STRING,
    addressMapLastChange               TimeStamp
}

addressMapTimeMark OBJECT-TYPE
    SYNTAX      TimeFilter
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A TimeFilter for this entry.  See the TimeFilter textual
        convention to see how this works."
    ::= { addressMapEntry 1 }

addressMapNetworkAddress OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The network address for this relation.

        This is represented as an octet string with
        specific semantics and length as identified
        by the protocolDirLocalIndex component of the
        index.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { addressMapEntry 2 }

addressMapSource OBJECT-TYPE
    SYNTAX      OBJECT IDENTIFIER
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The interface or port on which the associated network
         address was most recently seen.

        If this address mapping was discovered on an interface, this
        object shall identify the instance of the ifIndex
        object, defined in [3,5], for the desired interface.
        For example, if an entry were to receive data from
        interface #1, this object would be set to ifIndex.1.

        If this address mapping was discovered on a port, this
        object shall identify the instance of the rptrGroupPortIndex
        object, defined in [RFC1516], for the desired port.
        For example, if an entry were to receive data from
        group #1, port #1, this object would be set to
        rptrGroupPortIndex.1.1.

        Note that while the dataSource associated with this entry
        may only point to index objects, this object may at times
        point to repeater port objects. This situation occurs when
        the dataSource points to an interface which is a locally
        attached repeater and the agent has additional information
        about the source port of traffic seen on that repeater."
    ::= { addressMapEntry 3 }

addressMapPhysicalAddress OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The last source physical address on which the associated
        network address was seen.  If the protocol of the associated
        network address was encapsulated inside of a network-level or
        higher protocol, this will be the address of the next-lower
        protocol with the addressRecognitionCapable bit enabled and
        will be formatted as specified for that protocol."
    ::= { addressMapEntry 4 }

addressMapLastChange OBJECT-TYPE
    SYNTAX      TimeStamp
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The value of sysUpTime at the time this entry was last
        created or the values of the physical address changed.

        This can be used to help detect duplicate address problems, in
        which case this object will be updated frequently."
    ::= { addressMapEntry 5 }

--
-- Network Layer Host Group

--
-- Counts the amount of traffic sent from and to each network address
-- discovered by the probe.
-- Note that while the hlHostControlTable also has objects that
-- control an optional alHostTable, implementation of the alHostTable is
-- not required to fully implement this group.

hlHostControlTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF HlHostControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A list of higher layer (i.e. non-MAC) host table control entries.

        These entries will enable the collection of the network and
        application level host tables indexed by network addresses.
        Both the network and application level host tables are
        controlled by this table is so that they will both be created
        and deleted at the same time, further increasing the ease with
        which they can be implemented as a single datastore (note that
        if an implementation stores application layer host records in
        memory, it can derive network layer host records from them).

        Entries in the nlHostTable will be created on behalf of each
        entry in this table. Additionally, if this probe implements
        the alHostTable, entries in the alHostTable will be created on
        behalf of each entry in this table.

        Implementations are encouraged to add an entry per monitored
        interface upon initialization so that a default collection
        of host statistics is available."
    ::= { nlHost 1 }

hlHostControlEntry OBJECT-TYPE
    SYNTAX      HlHostControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the hlHostControlTable.

        An example of the indexing of this entry is
        hlHostControlNlDroppedFrames.1"
    INDEX { hlHostControlIndex }
    ::= { hlHostControlTable 1 }

HlHostControlEntry ::= SEQUENCE {
    hlHostControlIndex               Integer32,
    hlHostControlDataSource          DataSource,

    hlHostControlNlDroppedFrames     Counter32,
    hlHostControlNlInserts           Counter32,
    hlHostControlNlDeletes           Counter32,
    hlHostControlNlMaxDesiredEntries Integer32,
    hlHostControlAlDroppedFrames     Counter32,
    hlHostControlAlInserts           Counter32,
    hlHostControlAlDeletes           Counter32,
    hlHostControlAlMaxDesiredEntries Integer32,
    hlHostControlOwner               OwnerString,
    hlHostControlStatus              RowStatus
}

hlHostControlIndex OBJECT-TYPE
    SYNTAX      Integer32 (1..65535)
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "An index that uniquely identifies an entry in the
        hlHostControlTable.  Each such entry defines
        a function that discovers hosts on a particular
        interface and places statistics about them in the
        nlHostTable, and optionally in the alHostTable, on
        behalf of this hlHostControlEntry."
    ::= { hlHostControlEntry 1 }

hlHostControlDataSource OBJECT-TYPE
    SYNTAX      DataSource
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The source of data for the associated host tables.

        The statistics in this group reflect all packets
        on the local network segment attached to the
        identified interface.

        This object may not be modified if the associated
        hlHostControlStatus object is equal to active(1)."
    ::= { hlHostControlEntry 2 }

hlHostControlNlDroppedFrames OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
       "The total number of frames which were received by the probe
        and therefore not accounted for in the *StatsDropEvents, but
        for which the probe chose not to count for the associated

        nlHost entries for whatever reason.  Most often, this event
        occurs when the probe is out of some resources and decides to
        shed load from this collection.

        This count does not include packets that were not counted
        because they had MAC-layer errors.

        Note that if the nlHostTable is inactive because no protocols
        are enabled in the protocol directory, this value should be 0.

        Note that, unlike the dropEvents counter, this number is the
        exact number of frames dropped."
    ::= { hlHostControlEntry 3 }

hlHostControlNlInserts OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an nlHost entry has been
        inserted into the nlHost table.  If an entry is inserted, then
        deleted, and then inserted, this counter will be incremented
        by 2.

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlHostControlNlDeletes from hlHostControlNlInserts."
    ::= { hlHostControlEntry 4 }

hlHostControlNlDeletes OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an nlHost entry has been
        deleted from the nlHost table (for any reason).  If an entry
        is deleted, then inserted, and then deleted, this counter will
        be incremented by 2.

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal

        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlHostControlNlDeletes from hlHostControlNlInserts."
    ::= { hlHostControlEntry 5 }

hlHostControlNlMaxDesiredEntries OBJECT-TYPE
    SYNTAX      Integer32 (-1..2147483647)
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The maximum number of entries that are desired in the
        nlHostTable on behalf of this control entry. The probe will
        not create more than this number of associated entries in the
        table, but may choose to create fewer entries in this table
        for any reason including the lack of resources.

        If this object is set to a value less than the current number
        of entries, enough entries are chosen in an
        implementation-dependent manner and deleted so that the number
        of entries in the table equals the value of this object.

        If this value is set to -1, the probe may create any number
        of entries in this table.  If the associated
        hlHostControlStatus object is equal to `active', this
        object may not be modified.

        This object may be used to control how resources are allocated
        on the probe for the various RMON functions."
    ::= { hlHostControlEntry 6 }

hlHostControlAlDroppedFrames OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
       "The total number of frames which were received by the probe
        and therefore not accounted for in the *StatsDropEvents, but
        for which the probe chose not to count for the associated
        alHost entries for whatever reason.  Most often, this event
        occurs when the probe is out of some resources and decides to
        shed load from this collection.

        This count does not include packets that were not counted
        because they had MAC-layer errors.

        Note that if the alHostTable is not implemented or is inactive
        because no protocols are enabled in the protocol directory,
        this value should be 0.

        Note that, unlike the dropEvents counter, this number is the
        exact number of frames dropped."
    ::= { hlHostControlEntry 7 }

hlHostControlAlInserts OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an alHost entry has been
        inserted into the alHost table.  If an entry is inserted, then
        deleted, and then inserted, this counter will be incremented
        by 2.

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlHostControlAlDeletes from hlHostControlAlInserts."
    ::= { hlHostControlEntry 8 }

hlHostControlAlDeletes OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an alHost entry has been
        deleted from the alHost table (for any reason).  If an entry
        is deleted, then inserted, and then deleted, this counter will
        be incremented by 2.

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlHostControlAlDeletes from hlHostControlAlInserts."

    ::= { hlHostControlEntry 9 }

hlHostControlAlMaxDesiredEntries OBJECT-TYPE
    SYNTAX      Integer32 (-1..2147483647)
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The maximum number of entries that are desired in the alHost
        table on behalf of this control entry. The probe will not
        create more than this number of associated entries in the
        table, but may choose to create fewer entries in this table
        for any reason including the lack of resources.

        If this object is set to a value less than the current number
        of entries, enough entries are chosen in an
        implementation-dependent manner and deleted so that the number
        of entries in the table equals the value of this object.

        If this value is set to -1, the probe may create any number
        of entries in this table.  If the associated
        hlHostControlStatus object is equal to `active', this
        object may not be modified.

        This object may be used to control how resources are allocated
        on the probe for the various RMON functions."
    ::= { hlHostControlEntry 10 }

hlHostControlOwner OBJECT-TYPE
    SYNTAX      OwnerString
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The entity that configured this entry and is
        therefore using the resources assigned to it."
    ::= { hlHostControlEntry 11 }

hlHostControlStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The status of this hlHostControlEntry.

        An entry may not exist in the active state unless all
        objects in the entry have an appropriate value.

        If this object is not equal to active(1), all associated
        entries in the nlHostTable and alHostTable shall be deleted."

    ::= { hlHostControlEntry 12 }

nlHostTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF NlHostEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A collection of statistics for a particular network layer
        address that has been discovered on an interface of this
        device.

        The probe will populate this table for all network layer
        protocols in the protocol directory table whose value of
        protocolDirHostConfig is equal to supportedOn(3), and
        will delete any entries whose protocolDirEntry is deleted or
        has a protocolDirHostConfig value of supportedOff(2).

        The probe will add to this table all addresses seen
        as the source or destination address in all packets with no
        MAC errors, and will increment octet and packet counts in the
        table for all packets with no MAC errors."
::= { nlHost 2 }

nlHostEntry OBJECT-TYPE
    SYNTAX      NlHostEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the nlHostTable.

        The hlHostControlIndex value in the index identifies the
        hlHostControlEntry on whose behalf this entry was created.
        The protocolDirLocalIndex value in the index identifies the
        network layer protocol of the nlHostAddress.

        An example of the indexing of this entry is
        nlHostOutPkts.1.783495.18.4.128.2.6.6."
    INDEX { hlHostControlIndex, nlHostTimeMark,
            protocolDirLocalIndex, nlHostAddress }
    ::= { nlHostTable 1 }

NlHostEntry ::= SEQUENCE {
    nlHostTimeMark              TimeFilter,
    nlHostAddress               OCTET STRING,
    nlHostInPkts                ZeroBasedCounter32,
    nlHostOutPkts               ZeroBasedCounter32,
    nlHostInOctets              ZeroBasedCounter32,
    nlHostOutOctets             ZeroBasedCounter32,

    nlHostOutMacNonUnicastPkts  ZeroBasedCounter32,
    nlHostCreateTime            LastCreateTime
}

nlHostTimeMark OBJECT-TYPE
    SYNTAX      TimeFilter
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A TimeFilter for this entry.  See the TimeFilter textual
        convention to see how this works."
    ::= { nlHostEntry 1 }

nlHostAddress OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The network address for this nlHostEntry.

        This is represented as an octet string with
        specific semantics and length as identified
        by the protocolDirLocalIndex component of the index.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlHostEntry 2 }

nlHostInPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets without errors transmitted to
        this address since it was added to the nlHostTable.  Note that
        this is the number of link-layer packets, so if a single
        network-layer packet is fragmented into several link-layer
        frames, this counter is incremented several times."
    ::= { nlHostEntry 3 }

nlHostOutPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets without errors transmitted by

        this address since it was added to the nlHostTable.  Note that
        this is the number of link-layer packets, so if a single
        network-layer packet is fragmented into several link-layer
        frames, this counter is incremented several times."
    ::= { nlHostEntry 4 }

nlHostInOctets OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of octets transmitted to this address
        since it was added to the nlHostTable (excluding
        framing bits but including FCS octets), excluding
        those octets in packets that contained errors.

        Note this doesn't count just those octets in the particular
        protocol frames, but includes the entire packet that contained
        the protocol."
    ::= { nlHostEntry 5 }

nlHostOutOctets OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of octets transmitted by this address
        since it was added to the nlHostTable (excluding
        framing bits but including FCS octets), excluding
        those octets in packets that contained errors.

        Note this doesn't count just those octets in the particular
        protocol frames, but includes the entire packet that contained
        the protocol."
    ::= { nlHostEntry 6 }

nlHostOutMacNonUnicastPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets without errors transmitted by this
        address that were directed to any MAC broadcast addresses
        or to any MAC multicast addresses since this host was
        added to the nlHostTable. Note that this is the number of
        link-layer packets, so if a single network-layer packet is
        fragmented into several link-layer frames, this counter is
        incremented several times."

    ::= { nlHostEntry 7 }

nlHostCreateTime OBJECT-TYPE
    SYNTAX     LastCreateTime
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The value of sysUpTime when this entry was last activated.
        This can be used by the management station to ensure that the
        entry has not been deleted and recreated between polls."
    ::= { nlHostEntry 8 }

--
-- Network Layer Matrix Group
--
-- Counts the amount of traffic sent between each pair of network
-- addresses discovered by the probe.
-- Note that while the hlMatrixControlTable also has objects that
-- control optional alMatrixTables, implementation of the
-- alMatrixTables is not required to fully implement this group.

hlMatrixControlTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF HlMatrixControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A list of higher layer (i.e. non-MAC) matrix control entries.

        These entries will enable the collection of the network and
        application level matrix tables containing conversation
        statistics indexed by pairs of network addresses.
        Both the network and application level matrix tables are
        controlled by this table is so that they will both be created
        and deleted at the same time, further increasing the ease with
        which they can be implemented as a single datastore (note that
        if an implementation stores application layer matrix records
        in memory, it can derive network layer matrix records from
        them).

        Entries in the nlMatrixSDTable and nlMatrixDSTable will be
        created on behalf of each entry in this table.  Additionally,
        if this probe implements the alMatrix tables, entries in the
        alMatrix tables will be created on behalf of each entry in
        this table."
    ::= { nlMatrix 1 }

hlMatrixControlEntry OBJECT-TYPE
    SYNTAX      HlMatrixControlEntry

    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the hlMatrixControlTable.

        An example of indexing of this entry is
        hlMatrixControlNlDroppedFrames.1"
    INDEX { hlMatrixControlIndex }
    ::= { hlMatrixControlTable 1 }

HlMatrixControlEntry ::= SEQUENCE {
    hlMatrixControlIndex                  Integer32,
    hlMatrixControlDataSource             DataSource,
    hlMatrixControlNlDroppedFrames        Counter32,
    hlMatrixControlNlInserts              Counter32,
    hlMatrixControlNlDeletes              Counter32,
    hlMatrixControlNlMaxDesiredEntries    Integer32,
    hlMatrixControlAlDroppedFrames        Counter32,
    hlMatrixControlAlInserts              Counter32,
    hlMatrixControlAlDeletes              Counter32,
    hlMatrixControlAlMaxDesiredEntries    Integer32,
    hlMatrixControlOwner                  OwnerString,
    hlMatrixControlStatus                 RowStatus
}

hlMatrixControlIndex OBJECT-TYPE
    SYNTAX      Integer32 (1..65535)
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "An index that uniquely identifies an entry in the
        hlMatrixControlTable.  Each such entry defines
        a function that discovers conversations on a particular
        interface and places statistics about them in the
        nlMatrixSDTable and the nlMatrixDSTable, and optionally the
        alMatrixSDTable and alMatrixDSTable, on behalf of this
        hlMatrixControlEntry."
    ::= { hlMatrixControlEntry 1 }

hlMatrixControlDataSource OBJECT-TYPE
    SYNTAX      DataSource
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The source of the data for the associated matrix tables.

        The statistics in this group reflect all packets
        on the local network segment attached to the

        identified interface.

        This object may not be modified if the associated
        hlMatrixControlStatus object is equal to active(1)."
    ::= { hlMatrixControlEntry 2 }

hlMatrixControlNlDroppedFrames OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
       "The total number of frames which were received by the probe
        and therefore not accounted for in the *StatsDropEvents, but
        for which the probe chose not to count for this entry for
        whatever reason.  Most often, this event occurs when the probe
        is out of some resources and decides to shed load from this
        collection.

        This count does not include packets that were not counted
        because they had MAC-layer errors.

        Note that if the nlMatrixTables are inactive because no
        protocols are enabled in the protocol directory, this value
        should be 0.

        Note that, unlike the dropEvents counter, this number is the
        exact number of frames dropped."
    ::= { hlMatrixControlEntry 3 }

hlMatrixControlNlInserts OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an nlMatrix entry has been
        inserted into the nlMatrix tables.  If an entry is inserted,
        then deleted, and then inserted, this counter will be
        incremented by 2.  The addition of a conversation into both
        the nlMatrixSDTable and nlMatrixDSTable shall be counted as
        two insertions (even though every addition into one table must
        be accompanied by an insertion into the other).

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the sum of then nlMatrixSDTable and nlMatrixDSTable
        sizes can be determined by subtracting
        hlMatrixControlNlDeletes from hlMatrixControlNlInserts."
    ::= { hlMatrixControlEntry 4 }

hlMatrixControlNlDeletes OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an nlMatrix entry has been
        deleted from the nlMatrix tables (for any reason).  If an
        entry is deleted, then inserted, and then deleted, this
        counter will be incremented by 2.  The deletion of a
        conversation from both the nlMatrixSDTable and nlMatrixDSTable
        shall be counted as two deletions (even though every deletion
        from one table must be accompanied by a deletion from the
        other).

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlMatrixControlNlDeletes from hlMatrixControlNlInserts."
    ::= { hlMatrixControlEntry 5 }

hlMatrixControlNlMaxDesiredEntries OBJECT-TYPE
    SYNTAX      Integer32 (-1..2147483647)
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The maximum number of entries that are desired in the
        nlMatrix tables on behalf of this control entry. The probe
        will not create more than this number of associated entries in
        the table, but may choose to create fewer entries in this
        table for any reason including the lack of resources.

        If this object is set to a value less than the current number
        of entries, enough entries are chosen in an
        implementation-dependent manner and deleted so that the number
        of entries in the table equals the value of this object.

        If this value is set to -1, the probe may create any number
        of entries in this table.  If the associated

        hlMatrixControlStatus object is equal to `active', this
        object may not be modified.

        This object may be used to control how resources are allocated
        on the probe for the various RMON functions."
    ::= { hlMatrixControlEntry 6 }

hlMatrixControlAlDroppedFrames OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
       "The total number of frames which were received by the probe
        and therefore not accounted for in the *StatsDropEvents, but
        for which the probe chose not to count for this entry for
        whatever reason.  Most often, this event occurs when the probe
        is out of some resources and decides to shed load from this
        collection.

        This count does not include packets that were not counted
        because they had MAC-layer errors.

        Note that if the alMatrixTables are not implemented or are
        inactive because no protocols are enabled in the protocol
        directory, this value should be 0.

        Note that, unlike the dropEvents counter, this number is the
        exact number of frames dropped."
    ::= { hlMatrixControlEntry 7 }

hlMatrixControlAlInserts OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an alMatrix entry has been
        inserted into the alMatrix tables.  If an entry is inserted,
        then deleted, and then inserted, this counter will be
        incremented by 2.  The addition of a conversation into both
        the alMatrixSDTable and alMatrixDSTable shall be counted as
        two insertions (even though every addition into one table must
        be accompanied by an insertion into the other).

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal

        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlMatrixControlAlDeletes from hlMatrixControlAlInserts."
    ::= { hlMatrixControlEntry 8 }

hlMatrixControlAlDeletes OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of times an alMatrix entry has been
        deleted from the alMatrix tables.  If an entry is deleted,
        then inserted, and then deleted, this counter will be
        incremented by 2.  The deletion of a conversation from both
        the alMatrixSDTable and alMatrixDSTable shall be counted as
        two deletions (even though every deletion from one table must
        be accompanied by a deletion from the other).

        To allow for efficient implementation strategies, agents may
        delay updating this object for short periods of time.  For
        example, an implementation strategy may allow internal
        data structures to differ from those visible via SNMP for
        short periods of time.  This counter may reflect the internal
        data structures for those short periods of time.

        Note that the table size can be determined by subtracting
        hlMatrixControlAlDeletes from hlMatrixControlAlInserts."
    ::= { hlMatrixControlEntry 9 }

hlMatrixControlAlMaxDesiredEntries OBJECT-TYPE
    SYNTAX      Integer32 (-1..2147483647)
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The maximum number of entries that are desired in the
        alMatrix tables on behalf of this control entry. The probe
        will not create more than this number of associated entries in
        the table, but may choose to create fewer entries in this
        table for any reason including the lack of resources.

        If this object is set to a value less than the current number
        of entries, enough entries are chosen in an
        implementation-dependent manner and deleted so that the number
        of entries in the table equals the value of this object.

        If this value is set to -1, the probe may create any number
        of entries in this table.  If the associated

        hlMatrixControlStatus object is equal to `active', this
        object may not be modified.

        This object may be used to control how resources are allocated
        on the probe for the various RMON functions."
    ::= { hlMatrixControlEntry 10 }

hlMatrixControlOwner OBJECT-TYPE
    SYNTAX      OwnerString
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The entity that configured this entry and is
        therefore using the resources assigned to it."
    ::= { hlMatrixControlEntry 11 }

hlMatrixControlStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "The status of this hlMatrixControlEntry.

        An entry may not exist in the active state unless all
        objects in the entry have an appropriate value.

        If this object is not equal to active(1), all
        associated entries in the nlMatrixSDTable,
        nlMatrixDSTable, alMatrixSDTable, and the alMatrixDSTable
        shall be deleted by the agent."
    ::= { hlMatrixControlEntry 12 }

nlMatrixSDTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF NlMatrixSDEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A list of traffic matrix entries which collect statistics for
        conversations between two network-level addresses.  This table
        is indexed first by the source address and then by the
        destination address to make it convenient to collect all
        conversations from a particular address.

        The probe will populate this table for all network layer
        protocols in the protocol directory table whose value of
        protocolDirMatrixConfig is equal to supportedOn(3), and
        will delete any entries whose protocolDirEntry is deleted or
        has a protocolDirMatrixConfig value of supportedOff(2).

        The probe will add to this table all pairs of addresses
        seen in all packets with no MAC errors, and will increment
        octet and packet counts in the table for all packets with no
        MAC errors.

        Further, this table will only contain entries that have a
        corresponding entry in the nlMatrixDSTable with the same
        source address and destination address."
    ::= { nlMatrix 2 }

nlMatrixSDEntry OBJECT-TYPE
    SYNTAX      NlMatrixSDEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the nlMatrixSDTable.

        The hlMatrixControlIndex value in the index identifies the
        hlMatrixControlEntry on whose behalf this entry was created.
        The protocolDirLocalIndex value in the index identifies the
        network layer protocol of the nlMatrixSDSourceAddress and
        nlMatrixSDDestAddress.

        An example of the indexing of this table is
        nlMatrixSDPkts.1.783495.18.4.128.2.6.6.4.128.2.6.7"
    INDEX { hlMatrixControlIndex, nlMatrixSDTimeMark,
            protocolDirLocalIndex,
            nlMatrixSDSourceAddress, nlMatrixSDDestAddress }
    ::= { nlMatrixSDTable 1 }

NlMatrixSDEntry ::= SEQUENCE {
    nlMatrixSDTimeMark              TimeFilter,
    nlMatrixSDSourceAddress         OCTET STRING,
    nlMatrixSDDestAddress           OCTET STRING,
    nlMatrixSDPkts                  ZeroBasedCounter32,
    nlMatrixSDOctets                ZeroBasedCounter32,
    nlMatrixSDCreateTime            LastCreateTime
}

nlMatrixSDTimeMark OBJECT-TYPE
    SYNTAX      TimeFilter
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A TimeFilter for this entry.  See the TimeFilter textual
        convention to see how this works."
    ::= { nlMatrixSDEntry 1 }

nlMatrixSDSourceAddress OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The network source address for this nlMatrixSDEntry.

        This is represented as an octet string with
        specific semantics and length as identified
        by the protocolDirLocalIndex component of the index.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlMatrixSDEntry 2 }

nlMatrixSDDestAddress OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The network destination address for this
        nlMatrixSDEntry.

        This is represented as an octet string with
        specific semantics and length as identified
        by the protocolDirLocalIndex component of the index.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlMatrixSDEntry 3 }

nlMatrixSDPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets without errors transmitted from the
        source address to the destination address since this entry was
        added to the nlMatrixSDTable.  Note that this is the number of
        link-layer packets, so if a single network-layer packet is
        fragmented into several link-layer frames, this counter is
        incremented several times."
    ::= { nlMatrixSDEntry 4 }

nlMatrixSDOctets OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of octets transmitted from the source address to
        the destination address since this entry was added to the
        nlMatrixSDTable (excluding framing bits but
        including FCS octets), excluding those octets in packets that
        contained errors.

        Note this doesn't count just those octets in the particular
        protocol frames, but includes the entire packet that contained
        the protocol."
    ::= { nlMatrixSDEntry 5 }

nlMatrixSDCreateTime OBJECT-TYPE
    SYNTAX     LastCreateTime
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The value of sysUpTime when this entry was last activated.
        This can be used by the management station to ensure that the
        entry has not been deleted and recreated between polls."
    ::= { nlMatrixSDEntry 6 }

-- Traffic matrix tables from destination to source

nlMatrixDSTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF NlMatrixDSEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A list of traffic matrix entries which collect statistics for
        conversations between two network-level addresses.  This table
        is indexed first by the destination address and then by the
        source address to make it convenient to collect all
        conversations to a particular address.

        The probe will populate this table for all network layer
        protocols in the protocol directory table whose value of
        protocolDirMatrixConfig is equal to supportedOn(3), and
        will delete any entries whose protocolDirEntry is deleted or
        has a protocolDirMatrixConfig value of supportedOff(2).

        The probe will add to this table all pairs of addresses
        seen in all packets with no MAC errors, and will increment

        octet and packet counts in the table for all packets with no
        MAC errors.

        Further, this table will only contain entries that have a
        corresponding entry in the nlMatrixSDTable with the same
        source address and destination address."
    ::= { nlMatrix 3 }

nlMatrixDSEntry OBJECT-TYPE
    SYNTAX      NlMatrixDSEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the nlMatrixDSTable.

        The hlMatrixControlIndex value in the index identifies the
        hlMatrixControlEntry on whose behalf this entry was created.
        The protocolDirLocalIndex value in the index identifies the
        network layer protocol of the nlMatrixDSSourceAddress and
        nlMatrixDSDestAddress.

        An example of the indexing of this table is
        nlMatrixDSPkts.1.783495.18.4.128.2.6.7.4.128.2.6.6"
    INDEX { hlMatrixControlIndex, nlMatrixDSTimeMark,
            protocolDirLocalIndex,
            nlMatrixDSDestAddress, nlMatrixDSSourceAddress }
    ::= { nlMatrixDSTable 1 }

NlMatrixDSEntry ::= SEQUENCE {
    nlMatrixDSTimeMark                 TimeFilter,
    nlMatrixDSSourceAddress            OCTET STRING,
    nlMatrixDSDestAddress              OCTET STRING,
    nlMatrixDSPkts                     ZeroBasedCounter32,
    nlMatrixDSOctets                   ZeroBasedCounter32,
    nlMatrixDSCreateTime               LastCreateTime
}

nlMatrixDSTimeMark OBJECT-TYPE
    SYNTAX      TimeFilter
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A TimeFilter for this entry.  See the TimeFilter textual
        convention to see how this works."
    ::= { nlMatrixDSEntry 1 }

nlMatrixDSSourceAddress OBJECT-TYPE
    SYNTAX      OCTET STRING

    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The network source address for this nlMatrixDSEntry.

        This is represented as an octet string with
        specific semantics and length as identified
        by the protocolDirLocalIndex component of the index.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlMatrixDSEntry 2 }

nlMatrixDSDestAddress OBJECT-TYPE
    SYNTAX      OCTET STRING
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "The network destination address for this
        nlMatrixDSEntry.

        This is represented as an octet string with
        specific semantics and length as identified
        by the protocolDirLocalIndex component of the index.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlMatrixDSEntry 3 }

nlMatrixDSPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets without errors transmitted from the
        source address to the destination address since this entry was
        added to the nlMatrixDSTable.  Note that this is the number of
        link-layer packets, so if a single network-layer packet is
        fragmented into several link-layer frames, this counter is
        incremented several times."
    ::= { nlMatrixDSEntry 4 }

nlMatrixDSOctets OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32

    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of octets transmitted from the source address
        to the destination address since this entry was added to the
        nlMatrixDSTable (excluding framing bits but
        including FCS octets), excluding those octets in packets that
        contained errors.

        Note this doesn't count just those octets in the particular
        protocol frames, but includes the entire packet that contained
        the protocol."
    ::= { nlMatrixDSEntry 5 }

nlMatrixDSCreateTime OBJECT-TYPE
    SYNTAX     LastCreateTime
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The value of sysUpTime when this entry was last activated.
        This can be used by the management station to ensure that the
        entry has not been deleted and recreated between polls."
    ::= { nlMatrixDSEntry 6 }

nlMatrixTopNControlTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF NlMatrixTopNControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A set of parameters that control the creation of a
        report of the top N matrix entries according to
        a selected metric."
    ::= { nlMatrix 4 }

nlMatrixTopNControlEntry OBJECT-TYPE
    SYNTAX      NlMatrixTopNControlEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the nlMatrixTopNControlTable.

        An example of the indexing of this table is
        nlMatrixTopNControlDuration.3"
    INDEX { nlMatrixTopNControlIndex }
    ::= { nlMatrixTopNControlTable 1 }

NlMatrixTopNControlEntry ::= SEQUENCE {
    nlMatrixTopNControlIndex            Integer32,

    nlMatrixTopNControlMatrixIndex      Integer32,
    nlMatrixTopNControlRateBase         INTEGER,
    nlMatrixTopNControlTimeRemaining    Integer32,
    nlMatrixTopNControlGeneratedReports Counter32,
    nlMatrixTopNControlDuration         Integer32,
    nlMatrixTopNControlRequestedSize    Integer32,
    nlMatrixTopNControlGrantedSize      Integer32,
    nlMatrixTopNControlStartTime        TimeStamp,
    nlMatrixTopNControlOwner            OwnerString,
    nlMatrixTopNControlStatus           RowStatus
}

nlMatrixTopNControlIndex OBJECT-TYPE
    SYNTAX     Integer32 (1..65535)
    MAX-ACCESS not-accessible
    STATUS     current
    DESCRIPTION
        "An index that uniquely identifies an entry
        in the nlMatrixTopNControlTable.  Each such
        entry defines one top N report prepared for
        one interface."
    ::= { nlMatrixTopNControlEntry 1 }

nlMatrixTopNControlMatrixIndex OBJECT-TYPE
    SYNTAX     Integer32 (1..65535)
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "The nlMatrix[SD/DS] table for which a top N report will be
        prepared on behalf of this entry.  The nlMatrix[SD/DS] table
        is identified by the value of the hlMatrixControlIndex
        for that table - that value is used here to identify the
        particular table.

        This object may not be modified if the associated
        nlMatrixTopNControlStatus object is equal to active(1)."
    ::= { nlMatrixTopNControlEntry 2 }

nlMatrixTopNControlRateBase OBJECT-TYPE
    SYNTAX      INTEGER {
                    nlMatrixTopNPkts(1),
                    nlMatrixTopNOctets(2)
                }
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "The variable for each nlMatrix[SD/DS] entry that the
        nlMatrixTopNEntries are sorted by.

        This object may not be modified if the associated
        nlMatrixTopNControlStatus object is equal to active(1)."
    ::= { nlMatrixTopNControlEntry 3 }

nlMatrixTopNControlTimeRemaining OBJECT-TYPE
    SYNTAX     Integer32 (0..2147483647)
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "The number of seconds left in the report currently
        being collected.  When this object is modified by
        the management station, a new collection is started,
        possibly aborting a currently running report.  The
        new value is used as the requested duration of this
        report, and is immediately loaded into the associated
        nlMatrixTopNControlDuration object.
        When the report finishes, the probe will automatically
        start another collection with the same initial value
        of nlMatrixTopNControlTimeRemaining.  Thus the management
        station may simply read the resulting reports repeatedly,
        checking the startTime and duration each time to ensure that a
        report was not missed or that the report parameters were not
        changed.

        While the value of this object is non-zero, it decrements
        by one per second until it reaches zero.  At the time
        that this object decrements to zero, the report is made
        accessible in the nlMatrixTopNTable, overwriting any report
        that may be there.

        When this object is modified by the management station, any
        associated entries in the nlMatrixTopNTable shall be deleted.

        (Note that this is a different algorithm than the one used in
        the hostTopNTable)."
    DEFVAL { 1800 }
    ::= { nlMatrixTopNControlEntry 4 }

nlMatrixTopNControlGeneratedReports OBJECT-TYPE
    SYNTAX     Counter32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of reports that have been generated by this entry."
    ::= { nlMatrixTopNControlEntry 5 }

nlMatrixTopNControlDuration OBJECT-TYPE
    SYNTAX     Integer32

    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of seconds that this report has collected
        during the last sampling interval.

        When the associated nlMatrixTopNControlTimeRemaining object is
        set, this object shall be set by the probe to the
        same value and shall not be modified until the next
        time the nlMatrixTopNControlTimeRemaining is set.
        This value shall be zero if no reports have been
        requested for this nlMatrixTopNControlEntry."
    ::= { nlMatrixTopNControlEntry 6 }

nlMatrixTopNControlRequestedSize OBJECT-TYPE
    SYNTAX     Integer32 (0..2147483647)
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "The maximum number of matrix entries requested for this report.

        When this object is created or modified, the probe
        should set nlMatrixTopNControlGrantedSize as closely to this
        object as is possible for the particular probe
        implementation and available resources."
    DEFVAL { 150 }
    ::= { nlMatrixTopNControlEntry 7 }

nlMatrixTopNControlGrantedSize OBJECT-TYPE
    SYNTAX     Integer32 (0..2147483647)
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The maximum number of matrix entries in this report.

        When the associated nlMatrixTopNControlRequestedSize object is
        created or modified, the probe should set this
        object as closely to the requested value as is
        possible for the particular implementation and
        available resources. The probe must not lower this
        value except as a result of a set to the associated
        nlMatrixTopNControlRequestedSize object.

        If the value of nlMatrixTopNControlRateBase is equal to
        nlMatrixTopNPkts, when the next topN report is generated,
        matrix entries with the highest value of nlMatrixTopNPktRate
        shall be placed in this table in decreasing order of this rate
        until there is no more room or until there are no more

        matrix entries.

        If the value of nlMatrixTopNControlRateBase is equal to
        nlMatrixTopNOctets, when the next topN report is generated,
        matrix entries with the highest value of nlMatrixTopNOctetRate
        shall be placed in this table in decreasing order of this rate
        until there is no more room or until there are no more
        matrix entries.

        It is an implementation-specific matter how entries with the
        same value of nlMatrixTopNPktRate or nlMatrixTopNOctetRate are
        sorted.  It is also an implementation-specific matter as to
        whether or not zero-valued entries are available."
    ::= { nlMatrixTopNControlEntry 8 }

nlMatrixTopNControlStartTime OBJECT-TYPE
    SYNTAX     TimeStamp
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The value of sysUpTime when this top N report was
        last started.  In other words, this is the time that
        the associated nlMatrixTopNControlTimeRemaining object was
        modified to start the requested report or the time
        the report was last automatically (re)started.

        This object may be used by the management station to
        determine if a report was missed or not."
    ::= { nlMatrixTopNControlEntry 9 }

nlMatrixTopNControlOwner OBJECT-TYPE
    SYNTAX     OwnerString
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "The entity that configured this entry and is
        therefore using the resources assigned to it."
    ::= { nlMatrixTopNControlEntry 10 }

nlMatrixTopNControlStatus OBJECT-TYPE
    SYNTAX     RowStatus
    MAX-ACCESS read-create
    STATUS     current
    DESCRIPTION
        "The status of this nlMatrixTopNControlEntry.

        An entry may not exist in the active state unless all
        objects in the entry have an appropriate value.

        If this object is not equal to active(1), all
        associated entries in the nlMatrixTopNTable shall be deleted
        by the agent."
    ::= { nlMatrixTopNControlEntry 11 }

nlMatrixTopNTable OBJECT-TYPE
    SYNTAX     SEQUENCE OF NlMatrixTopNEntry
    MAX-ACCESS not-accessible
    STATUS     current
    DESCRIPTION
        "A set of statistics for those network layer matrix entries
        that have counted the highest number of octets or packets."
    ::= { nlMatrix 5 }

nlMatrixTopNEntry OBJECT-TYPE
    SYNTAX     NlMatrixTopNEntry
    MAX-ACCESS not-accessible
    STATUS     current
    DESCRIPTION
        "A conceptual row in the nlMatrixTopNTable.

        The nlMatrixTopNControlIndex value in the index identifies the
        nlMatrixTopNControlEntry on whose behalf this entry was
        created.

        An example of the indexing of this table is
        nlMatrixTopNPktRate.3.10"
    INDEX { nlMatrixTopNControlIndex, nlMatrixTopNIndex }
    ::= { nlMatrixTopNTable 1 }

NlMatrixTopNEntry ::= SEQUENCE {
    nlMatrixTopNIndex                 Integer32,
    nlMatrixTopNProtocolDirLocalIndex Integer32,
    nlMatrixTopNSourceAddress         OCTET STRING,
    nlMatrixTopNDestAddress           OCTET STRING,
    nlMatrixTopNPktRate               Gauge32,
    nlMatrixTopNReversePktRate        Gauge32,
    nlMatrixTopNOctetRate             Gauge32,
    nlMatrixTopNReverseOctetRate      Gauge32
}

nlMatrixTopNIndex OBJECT-TYPE
    SYNTAX     Integer32 (1..65535)
    MAX-ACCESS not-accessible
    STATUS     current
    DESCRIPTION
        "An index that uniquely identifies an entry in
        the nlMatrixTopNTable among those in the same report.

        This index is between 1 and N, where N is the
        number of entries in this report.

        If the value of nlMatrixTopNControlRateBase is equal to
        nlMatrixTopNPkts, increasing values of nlMatrixTopNIndex shall
        be assigned to entries with decreasing values of
        nlMatrixTopNPktRate until index N is assigned or there are no
        more nlMatrixTopNEntries.

        If the value of nlMatrixTopNControlRateBase is equal to
        nlMatrixTopNOctets, increasing values of nlMatrixTopNIndex
        shall be assigned to entries with decreasing values of
        nlMatrixTopNOctetRate until index N is assigned or there are
        no more nlMatrixTopNEntries."
    ::= { nlMatrixTopNEntry 1 }

nlMatrixTopNProtocolDirLocalIndex OBJECT-TYPE
    SYNTAX     Integer32 (1..2147483647)
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The protocolDirLocalIndex of the network layer protocol of
        this entry's network address."
    ::= { nlMatrixTopNEntry 2 }

nlMatrixTopNSourceAddress OBJECT-TYPE
    SYNTAX     OCTET STRING
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The network layer address of the source host in this
        conversation.

        This is represented as an octet string with
        specific semantics and length as identified
        by the associated nlMatrixTopNProtocolDirLocalIndex.

        For example, if the protocolDirLocalIndex indicates an
        encapsulation of ip, this object is encoded as a length
        octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlMatrixTopNEntry 3 }

nlMatrixTopNDestAddress OBJECT-TYPE
    SYNTAX     OCTET STRING
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION

        "The network layer address of the destination host in this
        conversation.

        This is represented as an octet string with
        specific semantics and length as identified
        by the associated nlMatrixTopNProtocolDirLocalIndex.

        For example, if the nlMatrixTopNProtocolDirLocalIndex
        indicates an encapsulation of ip, this object is encoded as a
        length octet of 4, followed by the 4 octets of the ip address,
        in network byte order."
    ::= { nlMatrixTopNEntry 4 }

nlMatrixTopNPktRate OBJECT-TYPE
    SYNTAX     Gauge32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of packets seen from the source host
        to the destination host during this sampling interval, counted
        using the rules for counting the nlMatrixSDPkts object.
        If the value of nlMatrixTopNControlRateBase is
        nlMatrixTopNPkts, this variable will be used to sort this
        report."
    ::= { nlMatrixTopNEntry 5 }

nlMatrixTopNReversePktRate OBJECT-TYPE
    SYNTAX     Gauge32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of packets seen from the destination host to the
        source host during this sampling interval, counted
        using the rules for counting the nlMatrixSDPkts object (note
        that the corresponding nlMatrixSDPkts object selected is the
        one whose source address is equal to nlMatrixTopNDestAddress
        and whose destination address is equal to
        nlMatrixTopNSourceAddress.)

        Note that if the value of nlMatrixTopNControlRateBase is equal
        to nlMatrixTopNPkts, the sort of topN entries is based
        entirely on nlMatrixTopNPktRate, and not on the value of this
        object."
    ::= { nlMatrixTopNEntry 6 }

nlMatrixTopNOctetRate OBJECT-TYPE
    SYNTAX     Gauge32
    MAX-ACCESS read-only

    STATUS     current
    DESCRIPTION
        "The number of octets seen from the source host
        to the destination host during this sampling interval, counted
        using the rules for counting the nlMatrixSDOctets object.  If
        the value of nlMatrixTopNControlRateBase is
        nlMatrixTopNOctets, this variable will be used to sort this
        report."
    ::= { nlMatrixTopNEntry 7 }

nlMatrixTopNReverseOctetRate OBJECT-TYPE
    SYNTAX     Gauge32
    MAX-ACCESS read-only
    STATUS     current
    DESCRIPTION
        "The number of octets seen from the destination host to the
        source host during this sampling interval, counted
        using the rules for counting the nlMatrixDSOctets object (note
        that the corresponding nlMatrixSDOctets object selected is the
        one whose source address is equal to nlMatrixTopNDestAddress
        and whose destination address is equal to
        nlMatrixTopNSourceAddress.)

        Note that if the value of nlMatrixTopNControlRateBase is equal
        to nlMatrixTopNOctets, the sort of topN entries is based
        entirely on nlMatrixTopNOctetRate, and not on the value of
        this object."
    ::= { nlMatrixTopNEntry 8 }

-- Application Layer Functions
--
-- The application layer host, matrix, and matrixTopN functions report
-- on protocol usage at the network layer or higher.  Note that the
-- use of the term application layer does not imply that only
-- application-layer protocols are counted, rather it means that
-- protocols up to and including the application layer are supported.

--
-- Application Layer Host Group
--
-- Counts the amount of traffic, by protocol, sent from and to each
-- network address discovered by the probe.
-- Implementation of this group requires implementation of the Network
-- Layer Host Group.

alHostTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF AlHostEntry
    MAX-ACCESS  not-accessible

    STATUS      current
    DESCRIPTION
        "A collection of statistics for a particular protocol from a
        particular network address that has been discovered on an
        interface of this device.

        The probe will populate this table for all protocols in the
        protocol directory table whose value of
        protocolDirHostConfig is equal to supportedOn(3), and
        will delete any entries whose protocolDirEntry is deleted or
        has a protocolDirHostConfig value of supportedOff(2).

        The probe will add to this table all addresses
        seen as the source or destination address in all packets with
        no MAC errors, and will increment octet and packet counts in
        the table for all packets with no MAC errors.  Further,
        entries will only be added to this table if their address
        exists in the nlHostTable and will be deleted from this table
        if their address is deleted from the nlHostTable."
    ::= { alHost 1 }

alHostEntry OBJECT-TYPE
    SYNTAX      AlHostEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A conceptual row in the alHostTable.

        The hlHostControlIndex value in the index identifies the
        hlHostControlEntry on whose behalf this entry was created.
        The first protocolDirLocalIndex value in the index identifies
        the network layer protocol of the address.
        The nlHostAddress value in the index identifies the network
        layer address of this entry.
        The second protocolDirLocalIndex value in the index identifies
        the protocol that is counted by this entry.

        An example of the indexing in this entry is
        alHostOutPkts.1.783495.18.4.128.2.6.6.34"
    INDEX { hlHostControlIndex, alHostTimeMark,
            protocolDirLocalIndex, nlHostAddress,
            protocolDirLocalIndex }
    ::= { alHostTable 1 }

AlHostEntry ::= SEQUENCE {
    alHostTimeMark                 TimeFilter,
    alHostInPkts                   ZeroBasedCounter32,
    alHostOutPkts                  ZeroBasedCounter32,

    alHostInOctets                 ZeroBasedCounter32,
    alHostOutOctets                ZeroBasedCounter32,
    alHostCreateTime               LastCreateTime
}

alHostTimeMark OBJECT-TYPE
    SYNTAX      TimeFilter
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
        "A TimeFilter for this entry.  See the TimeFilter textual
        convention to see how this works."
    ::= { alHostEntry 1 }

alHostInPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPTION
        "The number of packets of this protocol type without errors
        transmitted to this address since it was added to the
        alHostTable.  Note that this is the number of link-layer
        packets, so if a single network-layer packet is fragmented
        into several link-layer frames, this counter is incremented
        several times."
    ::= { alHostEntry 2 }

alHostOutPkts OBJECT-TYPE
    SYNTAX      ZeroBasedCounter32
    MAX-ACCESS  read-only
    STATUS      current
    DESCRIPT