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<pre>Network Working Group                                            D. Levi
Request for Comments: 2573                           SNMP Research, Inc.
Obsoletes: <a href="./rfc2273">2273</a>                                                 P. Meyer
Category: Standards Track                   Secure Computing Corporation
                                                              B. Stewart
                                                           Cisco Systems
                                                              April 1999


                           <span class="h1">SNMP Applications</span>

Status of this Memo

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

Copyright Notice

   Copyright (C) The Internet Society (1999). All Rights Reserved.

Abstract

   This memo describes five types of SNMP applications which make use of
   an SNMP engine as described in [<a href="./rfc2571" title="&quot;An Architecture for Describing SNMP Management Frameworks&quot;">RFC2571</a>].  The types of application
   described are Command Generators, Command Responders, Notification
   Originators, Notification Receivers, and Proxy Forwarders.

   This memo also defines MIB modules for specifying targets of
   management operations, for notification filtering, and for proxy
   forwarding.

Table Of Contents

   <a href="#section-1">1</a> Overview .....................................................    <a href="#page-2">2</a>
   <a href="#section-1.1">1.1</a> Command Generator Applications .............................    <a href="#page-3">3</a>
   <a href="#section-1.2">1.2</a> Command Responder Applications .............................    <a href="#page-3">3</a>
   <a href="#section-1.3">1.3</a> Notification Originator Applications .......................    <a href="#page-3">3</a>
   <a href="#section-1.4">1.4</a> Notification Receiver Applications .........................    <a href="#page-3">3</a>
   <a href="#section-1.5">1.5</a> Proxy Forwarder Applications ...............................    <a href="#page-4">4</a>
   <a href="#section-2">2</a> Management Targets ...........................................    <a href="#page-5">5</a>
   <a href="#section-3">3</a> Elements Of Procedure ........................................    <a href="#page-6">6</a>
   <a href="#section-3.1">3.1</a> Command Generator Applications .............................    <a href="#page-6">6</a>
   <a href="#section-3.2">3.2</a> Command Responder Applications .............................    <a href="#page-9">9</a>
   <a href="#section-3.3">3.3</a> Notification Originator Applications .......................   <a href="#page-14">14</a>
   <a href="#section-3.4">3.4</a> Notification Receiver Applications .........................   <a href="#page-17">17</a>



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   <a href="#section-3.5">3.5</a> Proxy Forwarder Applications ...............................   <a href="#page-19">19</a>
   <a href="#section-3.5.1">3.5.1</a> Request Forwarding .......................................   <a href="#page-20">20</a>
   <a href="#section-3.5.1.1">3.5.1.1</a> Processing an Incoming Request .........................   <a href="#page-20">20</a>
   <a href="#section-3.5.1.2">3.5.1.2</a> Processing an Incoming Response ........................   <a href="#page-23">23</a>
   <a href="#section-3.5.1.3">3.5.1.3</a> Processing an Incoming Internal-Class PDU ..............   <a href="#page-24">24</a>
   <a href="#section-3.5.2">3.5.2</a> Notification Forwarding ..................................   <a href="#page-25">25</a>
   <a href="#section-4">4</a> The Structure of the MIB Modules .............................   <a href="#page-28">28</a>
   <a href="#section-4.1">4.1</a> The Management Target MIB Module ...........................   <a href="#page-28">28</a>
   <a href="#section-4.1.1">4.1.1</a> Tag Lists ................................................   <a href="#page-29">29</a>
   <a href="#section-4.1.2">4.1.2</a> Definitions ..............................................   <a href="#page-30">30</a>
   <a href="#section-4.2">4.2</a> The Notification MIB Module ................................   <a href="#page-43">43</a>
   <a href="#section-4.2.1">4.2.1</a> Definitions ..............................................   <a href="#page-43">43</a>
   <a href="#section-4.3">4.3</a> The Proxy MIB Module .......................................   <a href="#page-55">55</a>
   <a href="#section-4.3.1">4.3.1</a> Definitions ..............................................   <a href="#page-55">55</a>
   5 Identification of Management Targets in Notification
        Originators ...............................................   <a href="#page-61">61</a>
   <a href="#section-6">6</a> Notification Filtering .......................................   <a href="#page-62">62</a>
   7 Management Target Translation in Proxy  Forwarder  Applica-
        tions .....................................................   <a href="#page-63">63</a>
   <a href="#section-7.1">7.1</a> Management Target Translation for Request Forwarding .......   <a href="#page-63">63</a>
   <a href="#section-7.2">7.2</a> Management Target Translation for Notification Forwarding
        ...........................................................   <a href="#page-64">64</a>
   <a href="#section-8">8</a> Intellectual Property ........................................   <a href="#page-65">65</a>
   <a href="#section-9">9</a> Acknowledgments ..............................................   <a href="#page-66">66</a>
   <a href="#section-10">10</a> Security Considerations .....................................   <a href="#page-67">67</a>
   <a href="#section-11">11</a> References ..................................................   <a href="#page-67">67</a>
   <a href="#section-12">12</a> Editors' Addresses...........................................   <a href="#page-69">69</a>
   <a href="#appendix-A">A</a>. Trap Configuration Example ..................................   <a href="#page-70">70</a>
   <a href="#appendix-B">B</a>. Full Copyright Statement ....................................   <a href="#page-72">72</a>


<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>.  Overview</span>

   This document describes five types of SNMP applications:

     - Applications which initiate SNMP Read-Class, and/or Write-Class
       requests, called 'command generators.'
     - Applications which respond to SNMP Read-Class, and/or Write-Class
       requests, called 'command responders.'
     - Applications which generate SNMP Notification-Class PDUs, called
       'notification originators.'
     - Applications which receive SNMP Notification-Class PDUs, called
       'notification receivers.'
     - Applications which forward SNMP messages, called 'proxy
       forwarders.'






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   Note that there are no restrictions on which types of applications
   may be associated with a particular SNMP engine.  For example, a
   single SNMP engine may, in fact, be associated with both command
   generator and command responder applications.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [<a href="./rfc2119" title="&quot;Key words for use in RFCs to Indicate Requirement Levels&quot;">RFC2119</a>].

<span class="h3"><a class="selflink" id="section-1.1" href="#section-1.1">1.1</a>.  Command Generator Applications</span>

   A command generator application initiates SNMP Read-Class and/or
   Write-Class requests, as well as processing the response to a request
   which it generated.

<span class="h3"><a class="selflink" id="section-1.2" href="#section-1.2">1.2</a>.  Command Responder Applications</span>

   A command responder application receives SNMP Read-Class and/or
   Write-Class requests destined for the local system as indicated by
   the fact that the contextEngineID in the received request is equal to
   that of the local engine through which the request was received.  The
   command responder application will perform the appropriate protocol
   operation, using access control, and will generate a response message
   to be sent to the request's originator.

<span class="h3"><a class="selflink" id="section-1.3" href="#section-1.3">1.3</a>.  Notification Originator Applications</span>

   A notification originator application conceptually monitors a system
   for particular events or conditions, and generates Notification-Class
   messages based on these events or conditions.  A notification
   originator must have a mechanism for determining where to send
   messages, and what SNMP version and security parameters to use when
   sending messages.  A mechanism and MIB module for this purpose is
   provided in this document.  Note that Notification-Class PDUs
   generated by a notification originator may be either Confirmed-Class
   or Unconfirmed-Class PDU types.

<span class="h3"><a class="selflink" id="section-1.4" href="#section-1.4">1.4</a>.  Notification Receiver Applications</span>

   A notification receiver application listens for notification
   messages, and generates response messages when a message containing a
   Confirmed-Class PDU is received.









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<span class="h3"><a class="selflink" id="section-1.5" href="#section-1.5">1.5</a>.  Proxy Forwarder Applications</span>

   A proxy forwarder application forwards SNMP messages.  Note that
   implementation of a proxy forwarder application is optional.  The
   sections describing proxy (4.5, 5.3, and 8) may be skipped for
   implementations that do not include a proxy forwarder application.

   The term "proxy" has historically been used very loosely, with
   multiple different meanings.  These different meanings include (among
   others):

   (1)  the forwarding of SNMP requests to other SNMP entities without
        regard for what managed object types are being accessed; for
        example, in order to forward an SNMP request from one transport
        domain to another, or to translate SNMP requests of one version
        into SNMP requests of another version;

   (2)  the translation of SNMP requests into operations of some non-
        SNMP management protocol; and

   (3)  support for aggregated managed objects where the value of one
        managed object instance depends upon the values of multiple
        other (remote) items of management information.

   Each of these scenarios can be advantageous; for example, support for
   aggregation of management information can significantly reduce the
   bandwidth requirements of large-scale management activities.

   However, using a single term to cover multiple different scenarios
   causes confusion.

   To avoid such confusion, this document uses the term "proxy" with a
   much more tightly defined meaning.  The term "proxy" is used in this
   document to refer to a proxy forwarder application which forwards
   either SNMP messages without regard for what managed objects are
   contained within those messages.  This definition is most closely
   related to the first definition above.  Note, however, that in the
   SNMP architecture [<a href="./rfc2571" title="&quot;An Architecture for Describing SNMP Management Frameworks&quot;">RFC2571</a>], a proxy forwarder is actually an
   application, and need not be associated with what is traditionally
   thought of as an SNMP agent.

   Specifically, the distinction between a traditional SNMP agent and a
   proxy forwarder application is simple:








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     -  a proxy forwarder application forwards SNMP messages to other
        SNMP engines according to the context, and irrespective of the
        specific managed object types being accessed, and forwards the
        response to such previously forwarded messages back to the SNMP
        engine from which the original message was received;

     -  in contrast, the command responder application that is part of
        what is traditionally thought of as an SNMP agent, and which
        processes SNMP requests according to the (names of the)
        individual managed object types and instances being accessed, is
        NOT a proxy forwarder application from the perspective of this
        document.

   Thus, when a proxy forwarder application forwards a request or
   notification for a particular contextEngineID / contextName pair, not
   only is the information on how to forward the request specifically
   associated with that context, but the proxy forwarder application has
   no need of a detailed definition of a MIB view (since the proxy
   forwarder application forwards the request irrespective of the
   managed object types).

   In contrast, a command responder application must have the detailed
   definition of the MIB view, and even if it needs to issue requests to
   other entities, via SNMP or otherwise, that need is dependent on the
   individual managed object instances being accessed (i.e., not only on
   the context).

   Note that it is a design goal of a proxy forwarder application to act
   as an intermediary between the endpoints of a transaction.  In
   particular, when forwarding Confirmed Notification-Class messages,
   the associated response is forwarded when it is received from the
   target to which the Notification-Class message was forwarded, rather
   than generating a response immediately when the Notification-Class
   message is received.

<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>.  Management Targets</span>

   Some types of applications (notification generators and proxy
   forwarders in particular) require a mechanism for determining where
   and how to send generated messages.  This document provides a
   mechanism and MIB module for this purpose.  The set of information
   that describes where and how to send a message is called a '
   Management Target', and consists of two kinds of information:

     -  Destination information, consisting of a transport domain and a
        transport address.  This is also termed a transport endpoint.





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     -  SNMP parameters, consisting of message processing model,
        security model, security level, and security name information.

   The SNMP-TARGET-MIB module described later in this document contains
   one table for each of these types of information.  There can be a
   many-to-many relationship in the MIB between these two types of
   information.  That is, there may be multiple transport endpoints
   associated with a particular set of SNMP parameters, or a particular
   transport endpoint may be associated with several sets of SNMP
   parameters.

<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>.  Elements Of Procedure</span>

   The following sections describe the procedures followed by each type
   of application when generating messages for transmission or when
   processing received messages.  Applications communicate with the
   Dispatcher using the abstract service interfaces defined in
   [<a href="./rfc2571" title="&quot;An Architecture for Describing SNMP Management Frameworks&quot;">RFC2571</a>].

<span class="h3"><a class="selflink" id="section-3.1" href="#section-3.1">3.1</a>.  Command Generator Applications</span>

   A command generator initiates an SNMP request by calling the
   Dispatcher using the following abstract service interface:

       statusInformation =              -- sendPduHandle if success
                                        -- errorIndication if failure
         sendPdu(

         IN   transportDomain           -- transport domain to be used
         IN   transportAddress          -- destination network address
         IN   messageProcessingModel    -- typically, SNMP version
         IN   securityModel             -- Security Model to use
         IN   securityName              -- on behalf of this principal
         IN   securityLevel             -- Level of Security requested
         IN   contextEngineID           -- data from/at this entity
         IN   contextName               -- data from/in this context
         IN   pduVersion                -- the version of the PDU
         IN   PDU                       -- SNMP Protocol Data Unit
         IN   expectResponse            -- TRUE or FALSE
              )

   Where:

     -  The transportDomain is that of the destination of the message.

     -  The transportAddress is that of the destination of the message.





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     -  The messageProcessingModel indicates which Message Processing
        Model the application wishes to use.

     -  The securityModel is the security model that the application
        wishes to use.

     -  The securityName is the security model independent name for the
        principal on whose behalf the application wishes the message is
        to be generated.

     -  The securityLevel is the security level that the application
        wishes to use.

     -  The contextEngineID is provided by the command generator if it
        wishes to explicitly specify the location of the management
        information it is requesting.

     -  The contextName is provided by the command generator if it
        wishes to explicitly specify the local context name for the
        management information it is requesting.

     -  The pduVersion indicates the version of the PDU to be sent.

     -  The PDU is a value constructed by the command generator
        containing the management operation that the command generator
        wishes to perform.

     -  The expectResponse argument indicates that a response is
        expected.

   The result of the sendPdu interface indicates whether the PDU was
   successfully sent.  If it was successfully sent, the returned value
   will be a sendPduHandle.  The command generator should store the
   sendPduHandle so that it can correlate a response to the original
   request.

   The Dispatcher is responsible for delivering the response to a
   particular request to the correct command generator application.  The
   abstract service interface used is:

       processResponsePdu(              -- process Response PDU
         IN   messageProcessingModel    -- typically, SNMP version
         IN   securityModel             -- Security Model in use
         IN   securityName              -- on behalf of this principal
         IN   securityLevel             -- Level of Security
         IN   contextEngineID           -- data from/at this SNMP entity
         IN   contextName               -- data from/in this context
         IN   pduVersion                -- the version of the PDU



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         IN   PDU                       -- SNMP Protocol Data Unit
         IN   statusInformation         -- success or errorIndication
         IN   sendPduHandle             -- handle from sendPdu
              )

   Where:

     -  The messageProcessingModel is the value from the received
        response.

     -  The securityModel is the value from the received response.

     -  The securityName is the value from the received response.

     -  The securityLevel is the value from the received response.

     -  The contextEngineID is the value from the received response.

     -  The contextName is the value from the received response.

     -  The pduVersion indicates the version of the PDU in the received
        response.

     -  The PDU is the value from the received response.

     -  The statusInformation indicates success or failure in receiving
        the response.

     -  The sendPduHandle is the value returned by the sendPdu call
        which generated the original request to which this is a
        response.

   The procedure when a command generator receives a message is as
   follows:

   (1)  If the received values of messageProcessingModel, securityModel,
        securityName, contextEngineID, contextName, and pduVersion are
        not all equal to the values used in the original request, the
        response is discarded.

   (2)  The operation type, request-id, error-status, error-index, and
        variable-bindings are extracted from the PDU and saved.  If the
        request-id is not equal to the value used in the original
        request, the response is discarded.

   (3)  At this point, it is up to the application to take an
        appropriate action.  The specific action is implementation
        dependent.  If the statusInformation indicates that the request



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        failed, an appropriate action might be to attempt to transmit
        the request again, or to notify the person operating the
        application that a failure occurred.

<span class="h3"><a class="selflink" id="section-3.2" href="#section-3.2">3.2</a>.  Command Responder Applications</span>

   Before a command responder application can process messages, it must
   first associate itself with an SNMP engine.  The abstract service
   interface used for this purpose is:

       statusInformation =        -- success or errorIndication
         registerContextEngineID(
         IN   contextEngineID     -- take responsibility for this one
         IN   pduType             -- the pduType(s) to be registered
              )

   Where:

     -  The statusInformation indicates success or failure of the
        registration attempt.

     -  The contextEngineID is equal to the snmpEngineID of the SNMP
        engine with which the command responder is registering.

     -  The pduType indicates a Read-Class and/or Write-Class PDU.

   Note that if another command responder application is already
   registered with an SNMP engine, any further attempts to register with
   the same contextEngineID and pduType will be denied.  This implies
   that separate command responder applications could register
   separately for the various pdu types.  However, in practice this is
   undesirable, and only a single command responder application should
   be registered with an SNMP engine at any given time.

   A command responder application can disassociate with an SNMP engine
   using the following abstract service interface:

       unregisterContextEngineID(
         IN   contextEngineID     -- give up responsibility for this one
         IN   pduType             -- the pduType(s) to be unregistered
              )

   Where:

     -  The contextEngineID is equal to the snmpEngineID of the SNMP
        engine with which the command responder is cancelling the
        registration.




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     -  The pduType indicates a Read-Class and/or Write-Class PDU.

   Once the command responder has registered with the SNMP engine, it
   waits to receive SNMP messages.  The abstract service interface used
   for receiving messages is:

   processPdu(                     -- process Request/Notification PDU
     IN   messageProcessingModel   -- typically, SNMP version
     IN   securityModel            -- Security Model in use
     IN   securityName             -- on behalf of this principal
     IN   securityLevel            -- Level of Security
     IN   contextEngineID          -- data from/at this SNMP entity
     IN   contextName              -- data from/in this context
     IN   pduVersion               -- the version of the PDU
     IN   PDU                      -- SNMP Protocol Data Unit
     IN   maxSizeResponseScopedPDU -- maximum size of the Response PDU
     IN   stateReference           -- reference to state information
          )                        -- needed when sending a response

   Where:

     -  The messageProcessingModel indicates which Message Processing
        Model received and processed the message.

     -  The securityModel is the value from the received message.

     -  The securityName is the value from the received message.

     -  The securityLevel is the value from the received message.

     -  The contextEngineID is the value from the received message.

     -  The contextName is the value from the received message.

     -  The pduVersion indicates the version of the PDU in the received
        message.

     -  The PDU is the value from the received message.

     -  The maxSizeResponseScopedPDU is the maximum allowable size of a
        ScopedPDU containing a Response PDU (based on the maximum
        message size that the originator of the message can accept).

     -  The stateReference is a value which references cached
        information about each received request message.  This value
        must be returned to the Dispatcher in order to generate a
        response.




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   The procedure when a message is received is as follows.

   (1)  The operation type is determined from the ASN.1 tag value
        associated with the PDU parameter.  The operation type should
        always be one of the types previously registered by the
        application.

   (2)  The request-id is extracted from the PDU and saved.

   (3)  Any PDU type specific parameters are extracted from the PDU and
        saved (for example, if the PDU type is an SNMPv2 GetBulk PDU,
        the non-repeaters and max-repetitions values are extracted).

   (4)  The variable-bindings are extracted from the PDU and saved.

   (5)  The management operation represented by the PDU type is
        performed with respect to the relevant MIB view within the
        context named by the contextName (for an SNMPv2 PDU type, the
        operation is performed according to the procedures set forth in
        [<a href="./rfc1905" title="&quot;Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)&quot;">RFC1905</a>]).  The relevant MIB view is determined by the
        securityLevel, securityModel, contextName, securityName, and the
        class of the PDU type.  To determine whether a particular object
        instance is within the relevant MIB view, the following abstract
        service interface is called:

       statusInformation =      -- success or errorIndication
         isAccessAllowed(
         IN   securityModel     -- Security Model in use
         IN   securityName      -- principal who wants to access
         IN   securityLevel     -- Level of Security
         IN   viewType          -- read, write, or notify view
         IN   contextName       -- context containing variableName
         IN   variableName      -- OID for the managed object
              )

   Where:

     -  The securityModel is the value from the received message.

     -  The securityName is the value from the received message.

     -  The securityLevel is the value from the received message.

     -  The viewType indicates whether the PDU type is a Read-Class or
        Write-Class operation.

     -  The contextName is the value from the received message.




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     -  The variableName is the object instance of the variable for
        which access rights are to be checked.

   Normally, the result of the management operation will be a new PDU
   value, and processing will continue in step (6) below.  However, at
   any time during the processing of the management operation:

     -  If the isAccessAllowed ASI returns a noSuchView, noAccessEntry,
        or noGroupName error, processing of the management operation is
        halted, a PDU value is constructed using the values from the
        originally received PDU, but replacing the error_status with an
        authorizationError code, and error_index value of 0, and control
        is passed to step (6) below.

     -  If the isAccessAllowed ASI returns an otherError, processing of
        the management operation is halted, a different PDU value is
        constructed using the values from the originally received PDU,
        but replacing the error_status with a genError code, and control
        is passed to step (6) below.

     -  If the isAccessAllowed ASI returns a noSuchContext error,
        processing of the management operation is halted, no result PDU
        is generated, the snmpUnknownContexts counter is incremented,
        and control is passed to step (6) below.

     -  If the context named by the contextName parameter is
        unavailable, processing of the management operation is halted,
        no result PDU is generated, the snmpUnavailableContexts counter
        is incremented, and control is passed to step (6) below.

   (6)  The Dispatcher is called to generate a response or report
        message.  The abstract service interface is:

   returnResponsePdu(
     IN   messageProcessingModel   -- typically, SNMP version
     IN   securityModel            -- Security Model in use
     IN   securityName             -- on behalf of this principal
     IN   securityLevel            -- same as on incoming request
     IN   contextEngineID          -- data from/at this SNMP entity
     IN   contextName              -- data from/in this context
     IN   pduVersion               -- the version of the PDU
     IN   PDU                      -- SNMP Protocol Data Unit
     IN   maxSizeResponseScopedPDU -- maximum size of the Response PDU
     IN   stateReference           -- reference to state information
                                   -- as presented with the request
     IN   statusInformation        -- success or errorIndication
          )                        -- error counter OID/value if error




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   Where:

     -  The messageProcessingModel is the value from the processPdu
        call.

     -  The securityModel is the value from the processPdu call.

     -  The securityName is the value from the processPdu call.

     -  The securityLevel is the value from the processPdu call.

     -  The contextEngineID is the value from the processPdu call.

     -  The contextName is the value from the processPdu call.

     -  The pduVersion indicates the version of the PDU to be returned.
        If no result PDU was generated, the pduVersion is an undefined
        value.

     -  The PDU is the result generated in step (5) above.  If no result
        PDU was generated, the PDU is an undefined value.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the value from the processPdu call.

     -  The statusInformation either contains an indication that no
        error occurred and that a response should be generated, or
        contains an indication that an error occurred along with the OID
        and counter value of the appropriate error counter object.

   Note that a command responder application should always call the
   returnResponsePdu abstract service interface, even in the event of an
   error such as a resource allocation error.  In the event of such an
   error, the PDU value passed to returnResponsePdu should contain
   appropriate values for errorStatus and errorIndex.

   Note that the text above describes situations where the
   snmpUnknownContexts counter is incremented, and where the
   snmpUnavailableContexts counter is incremented.  The difference
   between these is that the snmpUnknownContexts counter is incremented
   when a request is received for a context which unknown to the SNMP
   entity.  The snmpUnavailableContexts counter is incremented when a
   request is received for a context which is known to the SNMP entity,
   but is currently unavailable.  Determining when a context is





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   unavailable is implementation specific, and some implementations may
   never encounter this situation, and so may never increment the
   snmpUnavailableContexts counter.

<span class="h3"><a class="selflink" id="section-3.3" href="#section-3.3">3.3</a>.  Notification Originator Applications</span>

   A notification originator application generates SNMP messages
   containing Notification-Class PDUs (for example, SNMPv2-Trap PDUs or
   Inform PDUs).  There is no requirement as to what specific types of
   Notification-Class PDUs a particular implementation must be capable
   of generating.

   Notification originator applications require a mechanism for
   identifying the management targets to which notifications should be
   sent.  The particular mechanism used is implementation dependent.
   However, if an implementation makes the configuration of management
   targets SNMP manageable, it MUST use the SNMP-TARGET-MIB module
   described in this document.

   When a notification originator wishes to generate a notification, it
   must first determine in which context the information to be conveyed
   in the notification exists, i.e., it must determine the
   contextEngineID and contextName.  It must then determine the set of
   management targets to which the notification should be sent.  The
   application must also determine, for each management target, what
   specific PDU type the notification message should contain, and if it
   is to contain a Confirmed-Class PDU, the number of retries and
   retransmission algorithm.

   The mechanism by which a notification originator determines this
   information is implementation dependent.  Once the application has
   determined this information, the following procedure is performed for
   each management target:

   (1)  Any appropriate filtering mechanisms are applied to determine
        whether the notification should be sent to the management
        target.  If such filtering mechanisms determine that the
        notification should not be sent, processing continues with the
        next management target.  Otherwise,

   (2)  The appropriate set of variable-bindings is retrieved from local
        MIB instrumentation within the relevant MIB view.  The relevant
        MIB view is determined by the securityLevel, securityModel,
        contextName, and securityName of the management target.  To
        determine whether a particular object instance is within the
        relevant MIB view, the isAccessAllowed abstract service
        interface is used, in the same manner as described in the




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        preceding section.  If the statusInformation returned by
        isAccessAllowed does not indicate accessAllowed, the
        notification is not sent to the management target.

   (3)  The NOTIFICATION-TYPE OBJECT IDENTIFIER of the notification
        (this is the value of the element of the variable bindings whose
        name is snmpTrapOID.0, i.e., the second variable binding) is
        checked using the isAccessAllowed abstract service interface,
        using the same parameters used in the preceding step.  If the
        statusInformation returned by isAccessAllowed does not indicate
        accessAllowed, the notification is not sent to the management
        target.

   (4)  A PDU is constructed using a locally unique request-id value, a
        PDU type as determined by the implementation, an error-status
        and error-index value of 0, and the variable-bindings supplied
        previously in step (2).

   (5)  If the notification contains an Unconfirmed-Class PDU, the
        Dispatcher is called using the following abstract service
        interface:

       statusInformation =              -- sendPduHandle if success
                                        -- errorIndication if failure
         sendPdu(
         IN   transportDomain           -- transport domain to be used
         IN   transportAddress          -- destination network address
         IN   messageProcessingModel    -- typically, SNMP version
         IN   securityModel             -- Security Model to use
         IN   securityName              -- on behalf of this principal
         IN   securityLevel             -- Level of Security requested
         IN   contextEngineID           -- data from/at this entity
         IN   contextName               -- data from/in this context
         IN   pduVersion                -- the version of the PDU
         IN   PDU                       -- SNMP Protocol Data Unit
         IN   expectResponse            -- TRUE or FALSE
              )

   Where:

     -  The transportDomain is that of the management target.

     -  The transportAddress is that of the management target.

     -  The messageProcessingModel is that of the management target.

     -  The securityModel is that of the management target.




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     -  The securityName is that of the management target.

     -  The securityLevel is that of the management target.

     -  The contextEngineID is the value originally determined for the
        notification.

     -  The contextName is the value originally determined for the
        notification.

     -  The pduVersion is the version of the PDU to be sent.

     -  The PDU is the value constructed in step (3) above.

     -  The expectResponse argument indicates that no response is
        expected.

   Otherwise,

   (6)  If the notification contains a Confirmed-Class PDU, then:

        a)  The Dispatcher is called using the sendPdu abstract service
            interface as described in step (4) above, except that the
            expectResponse argument indicates that a response is
            expected.

        b)  The application caches information about the management
            target.

        c)  If a response is received within an appropriate time
            interval from the transport endpoint of the management
            target, the notification is considered acknowledged and the
            cached information is deleted.  Otherwise,

        d)  If a response is not received within an appropriate time
            period, or if a report indication is received, information
            about the management target is retrieved from the cache, and
            steps a) through d) are repeated.  The number of times these
            steps are repeated is equal to the previously determined
            retry count.  If this retry count is exceeded, the
            acknowledgement of the notification is considered to have
            failed, and processing of the notification for this
            management target is halted.  Note that some report
            indications might be considered a failure.  Such report
            indications should be interpreted to mean that the
            acknowledgement of the notification has failed.





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   Responses to Confirmed-Class PDU notifications will be received via
   the processResponsePdu abstract service interface.

   To summarize, the steps that a notification originator follows when
   determining where to send a notification are:

     -  Determine the targets to which the notification should be sent.

     -  Apply any required filtering to the list of targets.

     -  Determine which targets are authorized to receive the
        notification.

<span class="h3"><a class="selflink" id="section-3.4" href="#section-3.4">3.4</a>.  Notification Receiver Applications</span>

   Notification receiver applications receive SNMP Notification messages
   from the Dispatcher.  Before any messages can be received, the
   notification receiver must register with the Dispatcher using the
   registerContextEngineID abstract service interface.  The parameters
   used are:

     -  The contextEngineID is an undefined 'wildcard' value.
        Notifications are delivered to a registered notification
        receiver regardless of the contextEngineID contained in the
        notification message.

     -  The pduType indicates the type of notifications that the
        application wishes to receive (for example, SNMPv2-Trap PDUs or
        Inform PDUs).

   Once the notification receiver has registered with the Dispatcher,
   messages are received using the processPdu abstract service
   interface.  Parameters are:

     -  The messageProcessingModel indicates which Message Processing
        Model received and processed the message.

     -  The securityModel is the value from the received message.

     -  The securityName is the value from the received message.

     -  The securityLevel is the value from the received message.

     -  The contextEngineID is the value from the received message.

     -  The contextName is the value from the received message.





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     -  The pduVersion indicates the version of the PDU in the received
        message.

     -  The PDU is the value from the received message.

     -  The maxSizeResponseScopedPDU is the maximum allowable size of a
        ScopedPDU containing a Response PDU (based on the maximum
        message size that the originator of the message can accept).

     -  If the message contains an Unconfirmed-Class PDU, the
        stateReference is undefined and unused.  Otherwise, the
        stateReference is a value which references cached information
        about the notification.  This value must be returned to the
        Dispatcher in order to generate a response.

   When an Unconfirmed-Class PDU is delivered to a notification receiver
   application, it first extracts the SNMP operation type, request-id,
   error-status, error-index, and variable-bindings from the PDU.  After
   this, processing depends on the particular implementation.

   When a Confirmed-Class PDU is received, the notification receiver
   application follows the following procedure:

   (1)  The PDU type, request-id, error-status, error-index, and
        variable-bindings are extracted from the PDU.

   (2)  A Response-Class PDU is constructed using the extracted
        request-id and variable-bindings, and with error-status and
        error-index both set to 0.

   (3)  The Dispatcher is called to generate a response message using
        the returnResponsePdu abstract service interface.  Parameters
        are:

     -  The messageProcessingModel is the value from the processPdu
        call.

     -  The securityModel is the value from the processPdu call.

     -  The securityName is the value from the processPdu call.

     -  The securityLevel is the value from the processPdu call.

     -  The contextEngineID is the value from the processPdu call.

     -  The contextName is the value from the processPdu call.

     -  The pduVersion indicates the version of the PDU to be returned.



<span class="grey">Levi, et al.                Standards Track                    [Page 18]</span></pre>
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     -  The PDU is the result generated in step (2) above.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the value from the processPdu call.

     -  The statusInformation indicates that no error occurred and that
        a response should be generated.

<span class="h3"><a class="selflink" id="section-3.5" href="#section-3.5">3.5</a>.  Proxy Forwarder Applications</span>

   A proxy forwarder application deals with forwarding SNMP messages.
   There are four basic types of messages which a proxy forwarder
   application may need to forward.  These are grouped according to the
   class of PDU type contained in a message.  The four basic types of
   messages are:

     -  Those containing Read-Class or Write-Class PDU types (for
        example, Get, GetNext, GetBulk, and Set PDU types).  These deal
        with requesting or modifying information located within a
        particular context.

     -  Those containing Notification-Class PDU types (for example,
        SNMPv2-Trap and Inform PDU types).  These deal with
        notifications concerning information located within a particular
        context.

     -  Those containing a Response-Class PDU type.  Forwarding of
        Response PDUs always occurs as a result of receiving a response
        to a previously forwarded message.

     -  Those containing Internal-Class PDU types (for example, a Report
        PDU).  Forwarding of Internal-Class PDU types always occurs as a
        result of receiving an Internal-Class PDU in response to a
        previously forwarded message.

   For the first type, the proxy forwarder's role is to deliver a
   request for management information to an SNMP engine which is
   "closer" or "downstream in the path" to the SNMP engine which has
   access to that information, and to deliver the response containing
   the information back to the SNMP engine from which the request was
   received.  The context information in a request is used to determine
   which SNMP engine has access to the requested information, and this
   is used to determine where and how to forward the request.






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   For the second type, the proxy forwarder's role is to determine which
   SNMP engines should receive notifications about management
   information from a particular location.  The context information in a
   notification message determines the location to which the information
   contained in the notification applies.  This is used to determine
   which SNMP engines should receive notification about this
   information.

   For the third type, the proxy forwarder's role is to determine which
   previously forwarded request or notification (if any) the response
   matches, and to forward the response back to the initiator of the
   request or notification.

   For the fourth type, the proxy forwarder's role is to determine which
   previously forwarded request or notification (if any) the Internal-
   Class PDU matches, and to forward the Internal-Class PDU back to the
   initiator of the request or notification.

   When forwarding messages, a proxy forwarder application must perform
   a translation of incoming management target information into outgoing
   management target information.  How this translation is performed is
   implementation specific.  In many cases, this will be driven by a
   preconfigured translation table.  If a proxy forwarder application
   makes the contents of this table SNMP manageable, it MUST use the
   SNMP-PROXY-MIB module defined in this document.

<span class="h4"><a class="selflink" id="section-3.5.1" href="#section-3.5.1">3.5.1</a>.  Request Forwarding</span>

   There are two phases for request forwarding.  First, the incoming
   request needs to be passed through the proxy application.  Then, the
   resulting response needs to be passed back.  These phases are
   described in the following two sections.

<span class="h5"><a class="selflink" id="section-3.5.1.1" href="#section-3.5.1.1">3.5.1.1</a>.  Processing an Incoming Request</span>

   A proxy forwarder application that wishes to forward request messages
   must first register with the Dispatcher using the
   registerContextEngineID abstract service interface.  The proxy
   forwarder must register each contextEngineID for which it wishes to
   forward messages, as well as for each pduType.  Note that as the
   configuration of a proxy forwarder is changed, the particular
   contextEngineID values for which it is forwarding may change.  The
   proxy forwarder should call the registerContextEngineID and
   unregisterContextEngineID abstract service interfaces as needed to
   reflect its current configuration.






<span class="grey">Levi, et al.                Standards Track                    [Page 20]</span></pre>
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   A proxy forwarder application should never attempt to register a
   value of contextEngineID which is equal to the snmpEngineID of the
   SNMP engine to which the proxy forwarder is associated.

   Once the proxy forwarder has registered for the appropriate
   contextEngineID values, it can start processing messages.  The
   following procedure is used:

   (1)  A message is received using the processPdu abstract service
        interface.  The incoming management target information received
        from the processPdu interface is translated into outgoing
        management target information.  Note that this translation may
        vary for different values of contextEngineID and/or contextName.
        The translation should result in a single management target.

   (2)  If appropriate outgoing management target information cannot be
        found, the proxy forwarder increments the snmpProxyDrops counter
        [<a href="./rfc1907" title="&quot;Management Information Base for Version 2 of the Simple Network Management Protocol (SNMPv2)&quot;">RFC1907</a>], and then calls the Dispatcher using the
        returnResponsePdu abstract service interface.  Parameters are:

     -  The messageProcessingModel is the value from the processPdu
        call.

     -  The securityModel is the value from the processPdu call.

     -  The securityName is the value from the processPdu call.

     -  The securityLevel is the value from the processPdu call.

     -  The contextEngineID is the value from the processPdu call.

     -  The contextName is the value from the processPdu call.

     -  The pduVersion is the value from the processPdu call.

     -  The PDU is an undefined value.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the value from the processPdu call.

     -  The statusInformation indicates that an error occurred and
        includes the OID and value of the snmpProxyDrops object.

        Processing of the message stops at this point.  Otherwise,





<span class="grey">Levi, et al.                Standards Track                    [Page 21]</span></pre>
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   (3)  A new PDU is constructed.  A unique value of request-id should
        be used in the new PDU (this value will enable a subsequent
        response message to be correlated with this request).  The
        remainder of the new PDU is identical to the received PDU,
        unless the incoming SNMP version and the outgoing SNMP version
        support different PDU versions, in which case the proxy
        forwarder may need to perform a translation on the PDU (A method
        for performing such a translation is described in [<a href="#ref-COEX" title="&quot;Coexistence between Version 1, Version 2, and Version 3 of the Internet-standard Network Management Framework&quot;">COEX</a>].)

   (4)  The proxy forwarder calls the Dispatcher to generate the
        forwarded message, using the sendPdu abstract service interface.
        The parameters are:

     -  The transportDomain is that of the outgoing management target.

     -  The transportAddress is that of the outgoing management target.

     -  The messageProcessingModel is that of the outgoing management
        target.

     -  The securityModel is that of the outgoing management target.

     -  The securityName is that of the outgoing management target.

     -  The securityLevel is that of the outgoing management target.

     -  The contextEngineID is the value originally received.

     -  The contextName is the value originally received.

     -  The pduVersion is the version of the PDU to be sent.

     -  The PDU is the value constructed in step (3) above.

     -  The expectResponse argument indicates that a response is
        expected.  If the sendPdu call is unsuccessful, the proxy
        forwarder performs the steps described in (2) above.  Otherwise:

   (5)  The proxy forwarder caches the following information in order to
        match an incoming response to the forwarded request:

     -  The sendPduHandle returned from the call to sendPdu,

     -  The request-id from the received PDU.

     -  the contextEngineID,

     -  the contextName,



<span class="grey">Levi, et al.                Standards Track                    [Page 22]</span></pre>
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     -  the stateReference,

     -  the incoming management target information,

     -  the outgoing management information,

     -  any other information needed to match an incoming response to
        the forwarded request.

        If this information cannot be cached (possibly due to a lack of
        resources), the proxy forwarder performs the steps described in
        (2) above.  Otherwise:

   (6)  Processing of the request stops until a response to the
        forwarded request is received, or until an appropriate time
        interval has expired.  If this time interval expires before a
        response has been received, the cached information about this
        request is removed.

<span class="h5"><a class="selflink" id="section-3.5.1.2" href="#section-3.5.1.2">3.5.1.2</a>.  Processing an Incoming Response</span>

   A proxy forwarder follows the following procedure when an incoming
   response is received:

   (1)  The incoming response is received using the processResponsePdu
        interface.  The proxy forwarder uses the received parameters to
        locate an entry in its cache of pending forwarded requests.
        This is done by matching the received parameters with the cached
        values of sendPduHandle, contextEngineID, contextName, outgoing
        management target information, and the request-id contained in
        the received PDU (the proxy forwarder must extract the request-
        id for this purpose).  If an appropriate cache entry cannot be
        found, processing of the response is halted.  Otherwise:

   (2)  The cache information is extracted, and removed from the cache.

   (3)  A new Response-Class PDU is constructed, using the request-id
        value from the original forwarded request (as extracted from the
        cache).  All other values are identical to those in the received
        Response-Class PDU, unless the incoming SNMP version and the
        outgoing SNMP version support different PDU versions, in which
        case the proxy forwarder may need to perform a translation on
        the PDU.  (A method for performing such a translation is
        described in [<a href="#ref-COEX" title="&quot;Coexistence between Version 1, Version 2, and Version 3 of the Internet-standard Network Management Framework&quot;">COEX</a>].)

   (4)  The proxy forwarder calls the Dispatcher using the
        returnResponsePdu abstract service interface.  Parameters are:




<span class="grey">Levi, et al.                Standards Track                    [Page 23]</span></pre>
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     -  The messageProcessingModel indicates the Message Processing
        Model by which the original incoming message was processed.

     -  The securityModel is that of the original incoming management
        target extracted from the cache.

     -  The securityName is that of the original incoming management
        target extracted from the cache.

     -  The securityLevel is that of the original incoming management
        target extracted from the cache.

     -  The contextEngineID is the value extracted from the cache.

     -  The contextName is the value extracted from the cache.

     -  The pduVersion indicates the version of the PDU to be returned.

     -  The PDU is the (possibly translated) Response PDU.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the value extracted from the cache.

     -  The statusInformation indicates that no error occurred and that
        a Response PDU message should be generated.

<span class="h5"><a class="selflink" id="section-3.5.1.3" href="#section-3.5.1.3">3.5.1.3</a>.  Processing an Incoming Internal-Class PDU</span>

   A proxy forwarder follows the following procedure when an incoming
   Internal-Class PDU is received:

   (1)  The incoming Internal-Class PDU is received using the
        processResponsePdu interface.  The proxy forwarder uses the
        received parameters to locate an entry in its cache of pending
        forwarded requests.  This is done by matching the received
        parameters with the cached values of sendPduHandle.  If an
        appropriate cache entry cannot be found, processing of the
        Internal-Class PDU is halted.  Otherwise:

   (2)  The cache information is extracted, and removed from the cache.

   (3)  If the original incoming management target information indicates
        an SNMP version which does not support Report PDUs, processing
        of the Internal-Class PDU is halted.





<span class="grey">Levi, et al.                Standards Track                    [Page 24]</span></pre>
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   (4)  The proxy forwarder calls the Dispatcher using the
        returnResponsePdu abstract service interface.  Parameters are:

     -  The messageProcessingModel indicates the Message Processing
        Model by which the original incoming message was processed.

     -  The securityModel is that of the original incoming management
        target extracted from the cache.

     -  The securityName is that of the original incoming management
        target extracted from the cache.

     -  The securityLevel is that of the original incoming management
        target extracted from the cache.

     -  The contextEngineID is the value extracted from the cache.

     -  The contextName is the value extracted from the cache.

     -  The pduVersion indicates the version of the PDU to be returned.

     -  The PDU is unused.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the value extracted from the cache.

     -  The statusInformation contains values specific to the Internal-
        Class PDU type (for example, for a Report PDU, the
        statusInformation contains the contextEngineID, contextName,
        counter OID, and counter value received in the incoming Report
        PDU).

<span class="h4"><a class="selflink" id="section-3.5.2" href="#section-3.5.2">3.5.2</a>.  Notification Forwarding</span>

   A proxy forwarder receives notifications in the same manner as a
   notification receiver application, using the processPdu abstract
   service interface.  The following procedure is used when a
   notification is received:

   (1)  The incoming management target information received from the
        processPdu interface is translated into outgoing management
        target information.  Note that this translation may vary for
        different values of contextEngineID and/or contextName.  The
        translation may result in multiple management targets.





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   (2)  If appropriate outgoing management target information cannot be
        found and the notification was an Unconfirmed-Class PDU,
        processing of the notification is halted.  If appropriate
        outgoing management target information cannot be found and the
        notification was a Confirmed-Class PDU, the proxy forwarder
        increments the snmpProxyDrops object, and calls the Dispatcher
        using the returnResponsePdu abstract service interface.  The
        parameters are:

     -  The messageProcessingModel is the received value.

     -  The securityModel is the received value.

     -  The securityName is the received value.

     -  The securityLevel is the received value.

     -  The contextEngineID is the received value.

     -  The contextName is the received value.

     -  The pduVersion is the received value.

     -  The PDU is an undefined and unused value.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the received value.

     -  The statusInformation indicates that an error occurred and that
        a Report message should be generated.

   Processing of the message stops at this point.  Otherwise,

   (3)  The proxy forwarder generates a notification using the
        procedures described in the preceding section on Notification
        Originators, with the following exceptions:

     -  The contextEngineID and contextName values from the original
        received notification are used.

     -  The outgoing management targets previously determined are used.

     -  No filtering mechanisms are applied.






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     -  The variable-bindings from the original received notification
        are used, rather than retrieving variable-bindings from local
        MIB instrumentation.  In particular, no access-control is
        applied to these variable-bindings.

     -  If the original notification contains a Confirmed-Class PDU,
        then any outgoing management targets, for which the outgoing
        SNMP version does not support and PDU types which are both
        Notification-Class and Confirmed-Class PDUs, will not be used
        when generating the forwarded notifications.

     -  If, for any of the outgoing management targets, the incoming
        SNMP version and the outgoing SNMP version support different PDU
        versions, the proxy forwarder may need to perform a translation
        on the PDU.  (A method for performing such a translation is
        described in [<a href="#ref-COEX" title="&quot;Coexistence between Version 1, Version 2, and Version 3 of the Internet-standard Network Management Framework&quot;">COEX</a>].)

   (4)  If the original received notification contains an Unconfirmed-
        Class PDU, processing of the notification is now completed.
        Otherwise, the original received notification must contain a
        Confirmed-Class PDU, and processing continues.

   (5)  If the forwarded notifications included any Confirmed-Class
        PDUs, processing continues when the procedures described in the
        section for Notification Originators determine that either:

     -  None of the generated notifications containing Confirmed-Class
        PDUs have been successfully acknowledged within the longest of
        the time intervals, in which case processing of the original
        notification is halted, or,

     -  At least one of the generated notifications containing
        Confirmed-Class PDUs is successfully acknowledged, in which case
        a response to the original received notification containing an
        Confirmed-Class PDU is generated as described in the following
        steps.

   (6)  A Response-Class PDU is constructed, using the values of
        request-id and variable-bindings from the original received
        Notification-Class PDU, and error-status and error-index values
        of 0.

   (7)  The Dispatcher is called using the returnResponsePdu abstract
        service interface.  Parameters are:

     -  The messageProcessingModel is the originally received value.

     -  The securityModel is the originally received value.



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     -  The securityName is the originally received value.

     -  The securityLevel is the originally received value.

     -  The contextEngineID is the originally received value.

     -  The contextName is the originally received value.

     -  The pduVersion indicates the version of the PDU constructed in
        step (6) above.

     -  The PDU is the value constructed in step (6) above.

     -  The maxSizeResponseScopedPDU is a local value indicating the
        maximum size of a ScopedPDU that the application can accept.

     -  The stateReference is the originally received value.

     -  The statusInformation indicates that no error occurred and that
        a Response-Class PDU message should be generated.

<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>.  The Structure of the MIB Modules</span>

   There are three separate MIB modules described in this document, the
   management target MIB, the notification MIB, and the proxy MIB.  The
   following sections describe the structure of these three MIB modules.

   The use of these MIBs by particular types of applications is
   described later in this document:

     -  The use of the management target MIB and the notification MIB in
        notification originator applications is described in <a href="#section-6">section 6</a>.

     -  The use of the notification MIB for filtering notifications in
        notification originator applications is described in <a href="#section-7">section 7</a>.

     -  The use of the management target MIB and the proxy MIB in proxy
        forwarding applications is described in <a href="#section-8">section 8</a>.

<span class="h3"><a class="selflink" id="section-4.1" href="#section-4.1">4.1</a>.  The Management Target MIB Module</span>

   The SNMP-TARGET-MIB module contains objects for defining management
   targets.  It consists of two tables and conformance/compliance
   statements.







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   The first table, the snmpTargetAddrTable, contains information about
   transport domains and addresses.  It also contains an object,
   snmpTargetAddrTagList, which provides a mechanism for grouping
   entries.

   The second table, the snmpTargetParamsTable, contains information
   about SNMP version and security information to be used when sending
   messages to particular transport domains and addresses.

   The Management Target MIB is intended to provide a general-purpose
   mechanism for specifying transport address, and for specifying
   parameters of SNMP messages generated by an SNMP entity.  It is used
   within this document for generation of notifications and for proxy
   forwarding.  However, it may be used for other purposes.  If another
   document makes use of this MIB, that document is responsible for
   specifying how it is used.  For example, [<a href="#ref-COEX" title="&quot;Coexistence between Version 1, Version 2, and Version 3 of the Internet-standard Network Management Framework&quot;">COEX</a>] uses this MIB for
   source address validation of SNMPv1 messages.

<span class="h4"><a class="selflink" id="section-4.1.1" href="#section-4.1.1">4.1.1</a>.  Tag Lists</span>

   The snmpTargetAddrTagList object is used for grouping entries in the
   snmpTargetAddrTable.  The value of this object contains a list of tag
   values which are used to select target addresses to be used for a
   particular operation.

   A tag value, which may also be used in MIB objects other than
   snmpTargetAddrTagList, is an arbitrary string of octets, but may not
   contain a delimiter character.  Delimiter characters are defined to
   be one of the following characters:

     -  An ASCII space character (0x20).

     -  An ASCII TAB character (0x09).

     -  An ASCII carriage return (CR) character (0x0D).

     -  An ASCII line feed (LF) character (0x0B).

   In addition, a tag value may not have a zero length.  Generally, a
   particular MIB object may contain either

     -  a single tag value, in which case the value of the MIB object
        may not contain a delimiter character, or:

     -  a MIB object may contain a list of tag values, separated by
        single delimiter characters.





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   For a list of tag values, these constraints imply certain
   restrictions on the value of a MIB object:

     -  There cannot be a leading or trailing delimiter character.

     -  There cannot be multiple adjacent delimiter characters.

<span class="h4"><a class="selflink" id="section-4.1.2" href="#section-4.1.2">4.1.2</a>.  Definitions</span>

   SNMP-TARGET-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       MODULE-IDENTITY,
       OBJECT-TYPE,
       snmpModules,
       Counter32,
       Integer32

           FROM SNMPv2-SMI

       TEXTUAL-CONVENTION,
       TDomain,
       TAddress,
       TimeInterval,
       RowStatus,
       StorageType,
       TestAndIncr
           FROM SNMPv2-TC

       SnmpSecurityModel,
       SnmpMessageProcessingModel,
       SnmpSecurityLevel,
       SnmpAdminString
           FROM SNMP-FRAMEWORK-MIB

       MODULE-COMPLIANCE,
       OBJECT-GROUP
           FROM SNMPv2-CONF;

   snmpTargetMIB MODULE-IDENTITY
       LAST-UPDATED "9808040000Z"
       ORGANIZATION "IETF SNMPv3 Working Group"
       CONTACT-INFO
           "WG-email:   snmpv3@lists.tislabs.com
            Subscribe:  majordomo@lists.tislabs.com
                        In message body:  subscribe snmpv3

            Chair:      Russ Mundy



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                        Trusted Information Systems
            Postal:     3060 Washington Rd
                        Glenwood MD 21738
                        USA
            EMail:      mundy@tislabs.com
            Phone:      +1-301-854-6889

            Co-editor:  David B. Levi
                        SNMP Research, Inc.
            Postal:     3001 Kimberlin Heights Road
                        Knoxville, TN 37920-9716
            EMail:      levi@snmp.com
            Phone:      +1 423 573 1434

            Co-editor:  Paul Meyer
                        Secure Computing Corporation
            Postal:     2675 Long Lake Road
                        Roseville, MN 55113
            EMail:      paul_meyer@securecomputing.com
            Phone:      +1 651 628 1592

            Co-editor:  Bob Stewart
                        Cisco Systems, Inc.
            Postal:     170 West Tasman Drive
                        San Jose, CA 95134-1706
            EMail:      bstewart@cisco.com
            Phone:      +1 603 654 2686"
       DESCRIPTION
           "This MIB module defines MIB objects which provide
            mechanisms to remotely configure the parameters used
            by an SNMP entity for the generation of SNMP messages."
       REVISION    "9808040000Z"
       DESCRIPTION "Clarifications, published as
                    <a href="./rfc2573">RFC2573</a>."
       REVISION    "9707140000Z"
       DESCRIPTION "The initial revision, published as <a href="./rfc2273">RFC2273</a>."
       ::= { snmpModules 12 }

   snmpTargetObjects       OBJECT IDENTIFIER ::= { snmpTargetMIB 1 }
   snmpTargetConformance   OBJECT IDENTIFIER ::= { snmpTargetMIB 3 }

   SnmpTagValue ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "255a"
       STATUS       current
       DESCRIPTION
           "An octet string containing a tag value.
            Tag values are preferably in human-readable form.




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            To facilitate internationalization, this information
            is represented using the ISO/IEC IS 10646-1 character
            set, encoded as an octet string using the UTF-8
            character encoding scheme described in <a href="./rfc2279">RFC 2279</a>.

            Since additional code points are added by amendments
            to the 10646 standard from time to time,
            implementations must be prepared to encounter any code
            point from 0x00000000 to 0x7fffffff.

            The use of control codes should be avoided, and certain
            control codes are not allowed as described below.

            For code points not directly supported by user
            interface hardware or software, an alternative means
            of entry and display, such as hexadecimal, may be
            provided.

            For information encoded in 7-bit US-ASCII, the UTF-8
            representation is identical to the US-ASCII encoding.

            Note that when this TC is used for an object that
            is used or envisioned to be used as an index, then a
            SIZE restriction must be specified so that the number
            of sub-identifiers for any object instance does not
            exceed the limit of 128, as defined by [<a href="./rfc1905" title="&quot;Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)&quot;">RFC1905</a>].

            An object of this type contains a single tag value
            which is used to select a set of entries in a table.

            A tag value is an arbitrary string of octets, but
            may not contain a delimiter character.  Delimiter
            characters are defined to be one of the following:

                -  An ASCII space character (0x20).

                -  An ASCII TAB character (0x09).

                -  An ASCII carriage return (CR) character (0x0D).

                -  An ASCII line feed (LF) character (0x0B).

            Delimiter characters are used to separate tag values
            in a tag list.  An object of this type may only
            contain a single tag value, and so delimiter
            characters are not allowed in a value of this type.

            Some examples of valid tag values are:



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                - 'acme'

                - 'router'

                - 'host'

            The use of a tag value to select table entries is
            application and MIB specific."
       SYNTAX       OCTET STRING (SIZE (0..255))

   SnmpTagList ::= TEXTUAL-CONVENTION
       DISPLAY-HINT "255a"
       STATUS       current
       DESCRIPTION
           "An octet string containing a list of tag values.
            Tag values are preferably in human-readable form.

            To facilitate internationalization, this information
            is represented using the ISO/IEC IS 10646-1 character
            set, encoded as an octet string using the UTF-8
            character encoding scheme described in <a href="./rfc2279">RFC 2279</a>.

            Since additional code points are added by amendments
            to the 10646 standard from time to time,
            implementations must be prepared to encounter any code
            point from 0x00000000 to 0x7fffffff.

            The use of control codes should be avoided, except as
            described below.

            For code points not directly supported by user
            interface hardware or software, an alternative means
            of entry and display, such as hexadecimal, may be
            provided.

            For information encoded in 7-bit US-ASCII, the UTF-8
            representation is identical to the US-ASCII encoding.

            An object of this type contains a list of tag values
            which are used to select a set of entries in a table.

            A tag value is an arbitrary string of octets, but
            may not contain a delimiter character.  Delimiter
            characters are defined to be one of the following:

                -  An ASCII space character (0x20).

                -  An ASCII TAB character (0x09).



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                -  An ASCII carriage return (CR) character (0x0D).

                -  An ASCII line feed (LF) character (0x0B).

            Delimiter characters are used to separate tag values
            in a tag list.  Only a single delimiter character may
            occur between two tag values.  A tag value may not
            have a zero length.  These constraints imply certain
            restrictions on the contents of this object:

                - There cannot be a leading or trailing delimiter
                  character.

                - There cannot be multiple adjacent delimiter
                  characters.

            Some examples of valid tag lists are:

                - An empty string

                - 'acme router'

                - 'host managerStation'

            Note that although a tag value may not have a length of
            zero, an empty string is still valid.  This indicates
            an empty list (i.e. there are no tag values in the list).

            The use of the tag list to select table entries is
            application and MIB specific.  Typically, an application
            will provide one or more tag values, and any entry
            which contains some combination of these tag values
            will be selected."
       SYNTAX       OCTET STRING (SIZE (0..255))

   --
   --
   -- The snmpTargetObjects group
   --
   --

   snmpTargetSpinLock OBJECT-TYPE
       SYNTAX      TestAndIncr
       MAX-ACCESS  read-write
       STATUS      current
       DESCRIPTION
           "This object is used to facilitate modification of table
            entries in the SNMP-TARGET-MIB module by multiple



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            managers.  In particular, it is useful when modifying
            the value of the snmpTargetAddrTagList object.

            The procedure for modifying the snmpTargetAddrTagList
            object is as follows:

                1.  Retrieve the value of snmpTargetSpinLock and
                    of snmpTargetAddrTagList.

                2.  Generate a new value for snmpTargetAddrTagList.

                3.  Set the value of snmpTargetSpinLock to the
                    retrieved value, and the value of
                    snmpTargetAddrTagList to the new value.  If
                    the set fails for the snmpTargetSpinLock
                    object, go back to step 1."
       ::= { snmpTargetObjects 1 }

   snmpTargetAddrTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpTargetAddrEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A table of transport addresses to be used in the generation
            of SNMP messages."
       ::= { snmpTargetObjects 2 }

   snmpTargetAddrEntry OBJECT-TYPE
       SYNTAX      SnmpTargetAddrEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A transport address to be used in the generation
            of SNMP operations.

            Entries in the snmpTargetAddrTable are created and
            deleted using the snmpTargetAddrRowStatus object."
       INDEX { IMPLIED snmpTargetAddrName }
       ::= { snmpTargetAddrTable 1 }

   SnmpTargetAddrEntry ::= SEQUENCE {
       snmpTargetAddrName         SnmpAdminString,
       snmpTargetAddrTDomain      TDomain,
       snmpTargetAddrTAddress     TAddress,
       snmpTargetAddrTimeout      TimeInterval,
       snmpTargetAddrRetryCount   Integer32,
       snmpTargetAddrTagList      SnmpTagList,
       snmpTargetAddrParams       SnmpAdminString,



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       snmpTargetAddrStorageType  StorageType,
       snmpTargetAddrRowStatus    RowStatus
   }

   snmpTargetAddrName OBJECT-TYPE
       SYNTAX      SnmpAdminString (SIZE(1..32))
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "The locally arbitrary, but unique identifier associated
            with this snmpTargetAddrEntry."
       ::= { snmpTargetAddrEntry 1 }

   snmpTargetAddrTDomain OBJECT-TYPE
       SYNTAX      TDomain
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object indicates the transport type of the address
            contained in the snmpTargetAddrTAddress object."
       ::= { snmpTargetAddrEntry 2 }

   snmpTargetAddrTAddress OBJECT-TYPE
       SYNTAX      TAddress
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object contains a transport address.  The format of
            this address depends on the value of the
            snmpTargetAddrTDomain object."
       ::= { snmpTargetAddrEntry 3 }

   snmpTargetAddrTimeout OBJECT-TYPE
       SYNTAX      TimeInterval
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object should reflect the expected maximum round
            trip time for communicating with the transport address
            defined by this row.  When a message is sent to this
            address, and a response (if one is expected) is not
            received within this time period, an implementation
            may assume that the response will not be delivered.

            Note that the time interval that an application waits
            for a response may actually be derived from the value
            of this object.  The method for deriving the actual time
            interval is implementation dependent.  One such method



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            is to derive the expected round trip time based on a
            particular retransmission algorithm and on the number
            of timeouts which have occurred.  The type of message may
            also be considered when deriving expected round trip
            times for retransmissions.  For example, if a message is
            being sent with a securityLevel that indicates both
            authentication and privacy, the derived value may be
            increased to compensate for extra processing time spent
            during authentication and encryption processing."
       DEFVAL { 1500 }
       ::= { snmpTargetAddrEntry 4 }

   snmpTargetAddrRetryCount OBJECT-TYPE
       SYNTAX      Integer32 (0..255)
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object specifies a default number of retries to be
            attempted when a response is not received for a generated
            message.  An application may provide its own retry count,
            in which case the value of this object is ignored."
       DEFVAL { 3 }
       ::= { snmpTargetAddrEntry 5 }

   snmpTargetAddrTagList OBJECT-TYPE
       SYNTAX      SnmpTagList
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object contains a list of tag values which are
            used to select target addresses for a particular
            operation."
       DEFVAL { "" }
       ::= { snmpTargetAddrEntry 6 }

   snmpTargetAddrParams OBJECT-TYPE
       SYNTAX      SnmpAdminString (SIZE(1..32))
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The value of this object identifies an entry in the
            snmpTargetParamsTable.  The identified entry
            contains SNMP parameters to be used when generating
            messages to be sent to this transport address."
       ::= { snmpTargetAddrEntry 7 }

   snmpTargetAddrStorageType OBJECT-TYPE
       SYNTAX      StorageType



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       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The storage type for this conceptual row."
       DEFVAL { nonVolatile }
       ::= { snmpTargetAddrEntry 8 }

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

            To create a row in this table, a manager must
            set this object to either createAndGo(4) or
            createAndWait(5).

            Until instances of all corresponding columns are
            appropriately configured, the value of the
            corresponding instance of the snmpTargetAddrRowStatus
            column is 'notReady'.

            In particular, a newly created row cannot be made
            active until the corresponding instances of
            snmpTargetAddrTDomain, snmpTargetAddrTAddress, and
            snmpTargetAddrParams have all been set.

            The following objects may not be modified while the
            value of this object is active(1):
                - snmpTargetAddrTDomain
                - snmpTargetAddrTAddress
            An attempt to set these objects while the value of
            snmpTargetAddrRowStatus is active(1) will result in
            an inconsistentValue error."
       ::= { snmpTargetAddrEntry 9 }

   snmpTargetParamsTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpTargetParamsEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A table of SNMP target information to be used
            in the generation of SNMP messages."
       ::= { snmpTargetObjects 3 }

   snmpTargetParamsEntry OBJECT-TYPE
       SYNTAX      SnmpTargetParamsEntry



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       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A set of SNMP target information.

            Entries in the snmpTargetParamsTable are created and
            deleted using the snmpTargetParamsRowStatus object."
       INDEX { IMPLIED snmpTargetParamsName }
       ::= { snmpTargetParamsTable 1 }

   SnmpTargetParamsEntry ::= SEQUENCE {
       snmpTargetParamsName           SnmpAdminString,
       snmpTargetParamsMPModel        SnmpMessageProcessingModel,
       snmpTargetParamsSecurityModel  SnmpSecurityModel,
       snmpTargetParamsSecurityName   SnmpAdminString,
       snmpTargetParamsSecurityLevel  SnmpSecurityLevel,
       snmpTargetParamsStorageType    StorageType,
       snmpTargetParamsRowStatus      RowStatus
   }

   snmpTargetParamsName OBJECT-TYPE
       SYNTAX      SnmpAdminString (SIZE(1..32))
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "The locally arbitrary, but unique identifier associated
            with this snmpTargetParamsEntry."
       ::= { snmpTargetParamsEntry 1 }

   snmpTargetParamsMPModel OBJECT-TYPE
       SYNTAX      SnmpMessageProcessingModel
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The Message Processing Model to be used when generating
            SNMP messages using this entry."
       ::= { snmpTargetParamsEntry 2 }

   snmpTargetParamsSecurityModel OBJECT-TYPE
       SYNTAX      SnmpSecurityModel (1..2147483647)
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The Security Model to be used when generating SNMP
             messages using this entry.  An implementation may
             choose to return an inconsistentValue error if an
             attempt is made to set this variable to a value
             for a security model which the implementation does



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             not support."
       ::= { snmpTargetParamsEntry 3 }

   snmpTargetParamsSecurityName OBJECT-TYPE
       SYNTAX      SnmpAdminString
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The securityName which identifies the Principal on
            whose behalf SNMP messages will be generated using
            this entry."
       ::= { snmpTargetParamsEntry 4 }

   snmpTargetParamsSecurityLevel OBJECT-TYPE
       SYNTAX      SnmpSecurityLevel
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The Level of Security to be used when generating
            SNMP messages using this entry."
       ::= { snmpTargetParamsEntry 5 }

   snmpTargetParamsStorageType OBJECT-TYPE
       SYNTAX      StorageType
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The storage type for this conceptual row."
       DEFVAL { nonVolatile }
       ::= { snmpTargetParamsEntry 6 }

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

            To create a row in this table, a manager must
            set this object to either createAndGo(4) or
            createAndWait(5).

            Until instances of all corresponding columns are
            appropriately configured, the value of the
            corresponding instance of the snmpTargetParamsRowStatus
            column is 'notReady'.

            In particular, a newly created row cannot be made



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            active until the corresponding
            snmpTargetParamsMPModel,
            snmpTargetParamsSecurityModel,
            snmpTargetParamsSecurityName,
            and snmpTargetParamsSecurityLevel have all been set.
            The following objects may not be modified while the
            value of this object is active(1):
                - snmpTargetParamsMPModel
                - snmpTargetParamsSecurityModel
                - snmpTargetParamsSecurityName
                - snmpTargetParamsSecurityLevel
            An attempt to set these objects while the value of
            snmpTargetParamsRowStatus is active(1) will result in
            an inconsistentValue error."
       ::= { snmpTargetParamsEntry 7 }

   snmpUnavailableContexts OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The total number of packets received by the SNMP
            engine which were dropped because the context
            contained in the message was unavailable."
       ::= { snmpTargetObjects 4 }

   snmpUnknownContexts OBJECT-TYPE
       SYNTAX       Counter32
       MAX-ACCESS   read-only
       STATUS       current
       DESCRIPTION
           "The total number of packets received by the SNMP
            engine which were dropped because the context
            contained in the message was unknown."
       ::= { snmpTargetObjects 5 }

   --
   --
   -- Conformance information
   --
   --

   snmpTargetCompliances OBJECT IDENTIFIER ::=
                                           { snmpTargetConformance 1 }
   snmpTargetGroups      OBJECT IDENTIFIER ::=
                                           { snmpTargetConformance 2 }

   --



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   --
   -- Compliance statements
   --
   --
   snmpTargetCommandResponderCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
           "The compliance statement for SNMP entities which include
            a command responder application."
       MODULE -- This Module
           MANDATORY-GROUPS { snmpTargetCommandResponderGroup }
       ::= { snmpTargetCompliances 1 }

   snmpTargetBasicGroup OBJECT-GROUP
       OBJECTS {
           snmpTargetSpinLock,
           snmpTargetAddrTDomain,
           snmpTargetAddrTAddress,
           snmpTargetAddrTagList,
           snmpTargetAddrParams,
           snmpTargetAddrStorageType,
           snmpTargetAddrRowStatus,
           snmpTargetParamsMPModel,
           snmpTargetParamsSecurityModel,
           snmpTargetParamsSecurityName,
           snmpTargetParamsSecurityLevel,
           snmpTargetParamsStorageType,
           snmpTargetParamsRowStatus
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects providing basic remote
            configuration of management targets."
       ::= { snmpTargetGroups 1 }

   snmpTargetResponseGroup OBJECT-GROUP
       OBJECTS {
           snmpTargetAddrTimeout,
           snmpTargetAddrRetryCount
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects providing remote configuration
            of management targets for applications which generate
            SNMP messages for which a response message would be
            expected."
       ::= { snmpTargetGroups 2 }




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   snmpTargetCommandResponderGroup OBJECT-GROUP
       OBJECTS {
           snmpUnavailableContexts,
           snmpUnknownContexts
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects required for command responder
            applications, used for counting error conditions."
       ::= { snmpTargetGroups 3 }

   END

<span class="h3"><a class="selflink" id="section-4.2" href="#section-4.2">4.2</a>.  The Notification MIB Module</span>

   The SNMP-NOTIFICATION-MIB module contains objects for the remote
   configuration of the parameters used by an SNMP entity for the
   generation of notifications.  It consists of three tables and
   conformance/compliance statements.  The first table, the
   snmpNotifyTable, contains entries which select which entries in the
   snmpTargetAddrTable should be used for generating notifications, and
   the type of notifications to be generated.

   The second table sparsely augments the snmpTargetAddrTable with an
   object which is used to associate a set of filters with a particular
   management target.

   The third table defines filters which are used to limit the number of
   notifications which are generated using particular management
   targets.

<span class="h4"><a class="selflink" id="section-4.2.1" href="#section-4.2.1">4.2.1</a>.  Definitions</span>

   SNMP-NOTIFICATION-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       MODULE-IDENTITY,
       OBJECT-TYPE,
       snmpModules
           FROM SNMPv2-SMI

       RowStatus,
       StorageType
           FROM SNMPv2-TC

       SnmpAdminString
           FROM SNMP-FRAMEWORK-MIB




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       SnmpTagValue,
       snmpTargetParamsName
           FROM SNMP-TARGET-MIB

       MODULE-COMPLIANCE,
       OBJECT-GROUP
           FROM SNMPv2-CONF;

   snmpNotificationMIB MODULE-IDENTITY
       LAST-UPDATED "9808040000Z"
       ORGANIZATION "IETF SNMPv3 Working Group"
       CONTACT-INFO
           "WG-email:   snmpv3@lists.tislabs.com
            Subscribe:  majordomo@lists.tislabs.com
                        In message body:  subscribe snmpv3

            Chair:      Russ Mundy
                        Trusted Information Systems
            Postal:     3060 Washington Rd
                        Glenwood MD 21738
                        USA
            EMail:      mundy@tislabs.com
            Phone:      +1-301-854-6889

            Co-editor:  David B. Levi
                        SNMP Research, Inc.
            Postal:     3001 Kimberlin Heights Road
                        Knoxville, TN 37920-9716
            EMail:      levi@snmp.com
            Phone:      +1 423 573 1434

            Co-editor:  Paul Meyer
                        Secure Computing Corporation
            Postal:     2675 Long Lake Road
                        Roseville, MN 55113
            EMail:      paul_meyer@securecomputing.com
            Phone:      +1 651 628 1592

            Co-editor:  Bob Stewart
                        Cisco Systems, Inc.
            Postal:     170 West Tasman Drive
                        San Jose, CA 95134-1706
            EMail:      bstewart@cisco.com
            Phone:      +1 603 654 2686"
       DESCRIPTION
           "This MIB module defines MIB objects which provide
            mechanisms to remotely configure the parameters
            used by an SNMP entity for the generation of



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            notifications."
       REVISION    "9808040000Z"
       DESCRIPTION "Clarifications, published as
                    <a href="./rfc2573">RFC2573</a>"
       REVISION    "9707140000Z"
       DESCRIPTION "The initial revision, published as <a href="./rfc2273">RFC2273</a>."
       ::= { snmpModules 13 }

   snmpNotifyObjects       OBJECT IDENTIFIER ::=
                                             { snmpNotificationMIB 1 }
   snmpNotifyConformance   OBJECT IDENTIFIER ::=
                                             { snmpNotificationMIB 3 }

   --
   --
   -- The snmpNotifyObjects group
   --
   --

   snmpNotifyTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpNotifyEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "This table is used to select management targets which should
            receive notifications, as well as the type of notification
            which should be sent to each selected management target."
       ::= { snmpNotifyObjects 1 }

   snmpNotifyEntry OBJECT-TYPE
       SYNTAX      SnmpNotifyEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "An entry in this table selects a set of management targets
            which should receive notifications, as well as the type of
            notification which should be sent to each selected
            management target.

            Entries in the snmpNotifyTable are created and
            deleted using the snmpNotifyRowStatus object."
       INDEX { IMPLIED snmpNotifyName }
       ::= { snmpNotifyTable 1 }

   SnmpNotifyEntry ::= SEQUENCE {
       snmpNotifyName         SnmpAdminString,
       snmpNotifyTag          SnmpTagValue,
       snmpNotifyType         INTEGER,



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       snmpNotifyStorageType  StorageType,
       snmpNotifyRowStatus    RowStatus
   }

   snmpNotifyName OBJECT-TYPE
       SYNTAX      SnmpAdminString (SIZE(1..32))
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "The locally arbitrary, but unique identifier associated
            with this snmpNotifyEntry."
       ::= { snmpNotifyEntry 1 }

   snmpNotifyTag OBJECT-TYPE
       SYNTAX      SnmpTagValue
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object contains a single tag value which is used
            to select entries in the snmpTargetAddrTable.  Any entry
            in the snmpTargetAddrTable which contains a tag value
            which is equal to the value of an instance of this
            object is selected.  If this object contains a value
            of zero length, no entries are selected."
       DEFVAL { "" }
       ::= { snmpNotifyEntry 2 }

   snmpNotifyType OBJECT-TYPE
       SYNTAX      INTEGER {
                       trap(1),
                       inform(2)
                   }
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object determines the type of notification to
            be generated for entries in the snmpTargetAddrTable
            selected by the corresponding instance of
            snmpNotifyTag.  This value is only used when
            generating notifications, and is ignored when
            using the snmpTargetAddrTable for other purposes.

            If the value of this object is trap(1), then any
            messages generated for selected rows will contain
            Unconfirmed-Class PDUs.

            If the value of this object is inform(2), then any
            messages generated for selected rows will contain



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            Confirmed-Class PDUs.

            Note that if an SNMP entity only supports
            generation of Unconfirmed-Class PDUs (and not
            Confirmed-Class PDUs), then this object may be
            read-only."
       DEFVAL { trap }
       ::= { snmpNotifyEntry 3 }
   snmpNotifyStorageType OBJECT-TYPE
       SYNTAX      StorageType
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The storage type for this conceptual row."
       DEFVAL { nonVolatile }
       ::= { snmpNotifyEntry 4 }

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

            To create a row in this table, a manager must
            set this object to either createAndGo(4) or
            createAndWait(5)."
       ::= { snmpNotifyEntry 5 }

   snmpNotifyFilterProfileTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpNotifyFilterProfileEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "This table is used to associate a notification filter
            profile with a particular set of target parameters."
       ::= { snmpNotifyObjects 2 }

   snmpNotifyFilterProfileEntry OBJECT-TYPE
       SYNTAX      SnmpNotifyFilterProfileEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "An entry in this table indicates the name of the filter
            profile to be used when generating notifications using
            the corresponding entry in the snmpTargetParamsTable.

            Entries in the snmpNotifyFilterProfileTable are created



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            and deleted using the snmpNotifyFilterProfileRowStatus
            object."
       INDEX { IMPLIED snmpTargetParamsName }
       ::= { snmpNotifyFilterProfileTable 1 }

   SnmpNotifyFilterProfileEntry ::= SEQUENCE {
       snmpNotifyFilterProfileName         SnmpAdminString,
       snmpNotifyFilterProfileStorType     StorageType,
       snmpNotifyFilterProfileRowStatus    RowStatus
   }

   snmpNotifyFilterProfileName OBJECT-TYPE
       SYNTAX      SnmpAdminString (SIZE(1..32))
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The name of the filter profile to be used when generating
            notifications using the corresponding entry in the
            snmpTargetAddrTable."
       ::= { snmpNotifyFilterProfileEntry 1 }

   snmpNotifyFilterProfileStorType OBJECT-TYPE
       SYNTAX      StorageType
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The storage type of this conceptual row."
       DEFVAL { nonVolatile }
       ::= { snmpNotifyFilterProfileEntry 2 }

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

            To create a row in this table, a manager must
            set this object to either createAndGo(4) or
            createAndWait(5).

            Until instances of all corresponding columns are
            appropriately configured, the value of the
            corresponding instance of the
            snmpNotifyFilterProfileRowStatus column is 'notReady'.

            In particular, a newly created row cannot be made
            active until the corresponding instance of



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            snmpNotifyFilterProfileName has been set."
       ::= { snmpNotifyFilterProfileEntry 3 }

   snmpNotifyFilterTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpNotifyFilterEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "The table of filter profiles.  Filter profiles are used
            to determine whether particular management targets should
            receive particular notifications.

            When a notification is generated, it must be compared
            with the filters associated with each management target
            which is configured to receive notifications, in order to
            determine whether it may be sent to each such management
            target.

            A more complete discussion of notification filtering
            can be found in <a href="./rfc2573#section-6">section&nbsp;6. of [RFC2573]</a>."
       ::= { snmpNotifyObjects 3 }

   snmpNotifyFilterEntry OBJECT-TYPE
       SYNTAX      SnmpNotifyFilterEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "An element of a filter profile.

            Entries in the snmpNotifyFilterTable are created and
            deleted using the snmpNotifyFilterRowStatus object."
       INDEX {         snmpNotifyFilterProfileName,
               IMPLIED snmpNotifyFilterSubtree }
       ::= { snmpNotifyFilterTable 1 }

   SnmpNotifyFilterEntry ::= SEQUENCE {
       snmpNotifyFilterSubtree           OBJECT IDENTIFIER,
       snmpNotifyFilterMask              OCTET STRING,
       snmpNotifyFilterType              INTEGER,
       snmpNotifyFilterStorageType       StorageType,
       snmpNotifyFilterRowStatus         RowStatus
   }

   snmpNotifyFilterSubtree OBJECT-TYPE
       SYNTAX      OBJECT IDENTIFIER
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION



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           "The MIB subtree which, when combined with the corresponding
            instance of snmpNotifyFilterMask, defines a family of
            subtrees which are included in or excluded from the
            filter profile."
       ::= { snmpNotifyFilterEntry 1 }
   snmpNotifyFilterMask OBJECT-TYPE
       SYNTAX      OCTET STRING (SIZE(0..16))
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The bit mask which, in combination with the corresponding
            instance of snmpNotifyFilterSubtree, defines a family of
            subtrees which are included in or excluded from the
            filter profile.

            Each bit of this bit mask corresponds to a
            sub-identifier of snmpNotifyFilterSubtree, with the
            most significant bit of the i-th octet of this octet
            string value (extended if necessary, see below)
            corresponding to the (8*i - 7)-th sub-identifier, and
            the least significant bit of the i-th octet of this
            octet string corresponding to the (8*i)-th
            sub-identifier, where i is in the range 1 through 16.

            Each bit of this bit mask specifies whether or not
            the corresponding sub-identifiers must match when
            determining if an OBJECT IDENTIFIER matches this
            family of filter subtrees; a '1' indicates that an
            exact match must occur; a '0' indicates 'wild card',
            i.e., any sub-identifier value matches.

            Thus, the OBJECT IDENTIFIER X of an object instance
            is contained in a family of filter subtrees if, for
            each sub-identifier of the value of
            snmpNotifyFilterSubtree, either:

              the i-th bit of snmpNotifyFilterMask is 0, or

              the i-th sub-identifier of X is equal to the i-th
              sub-identifier of the value of
              snmpNotifyFilterSubtree.

            If the value of this bit mask is M bits long and
            there are more than M sub-identifiers in the
            corresponding instance of snmpNotifyFilterSubtree,
            then the bit mask is extended with 1's to be the
            required length.




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            Note that when the value of this object is the
            zero-length string, this extension rule results in
            a mask of all-1's being used (i.e., no 'wild card'),
            and the family of filter subtrees is the one
            subtree uniquely identified by the corresponding
            instance of snmpNotifyFilterSubtree."
       DEFVAL { ''H }
       ::= { snmpNotifyFilterEntry 2 }

   snmpNotifyFilterType OBJECT-TYPE
       SYNTAX      INTEGER {
                       included(1),
                       excluded(2)
                   }
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object indicates whether the family of filter subtrees
            defined by this entry are included in or excluded from a
            filter.  A more detailed discussion of the use of this
            object can be found in <a href="./rfc2573#section-6">section&nbsp;6. of [RFC2573]</a>."
       DEFVAL { included }
       ::= { snmpNotifyFilterEntry 3 }

   snmpNotifyFilterStorageType OBJECT-TYPE
       SYNTAX      StorageType
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The storage type of this conceptual row."
       DEFVAL { nonVolatile }
       ::= { snmpNotifyFilterEntry 4 }

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

            To create a row in this table, a manager must
            set this object to either createAndGo(4) or
            createAndWait(5)."
       ::= { snmpNotifyFilterEntry 5 }

   --
   --
   -- Conformance information



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   --
   --
   snmpNotifyCompliances OBJECT IDENTIFIER ::=
                                           { snmpNotifyConformance 1 }
   snmpNotifyGroups      OBJECT IDENTIFIER ::=
                                           { snmpNotifyConformance 2 }

   --
   --
   -- Compliance statements
   --
   --

   snmpNotifyBasicCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
           "The compliance statement for minimal SNMP entities which
            implement only SNMP Unconfirmed-Class notifications and
            read-create operations on only the snmpTargetAddrTable."
       MODULE SNMP-TARGET-MIB
           MANDATORY-GROUPS { snmpTargetBasicGroup }

           OBJECT snmpTargetParamsMPModel
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required."

           OBJECT snmpTargetParamsSecurityModel
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required."

           OBJECT snmpTargetParamsSecurityName
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required."

           OBJECT snmpTargetParamsSecurityLevel
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required."

           OBJECT snmpTargetParamsStorageType
           SYNTAX INTEGER {
               readOnly(5)
           }
           MIN-ACCESS    read-only
           DESCRIPTION



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               "Create/delete/modify access is not required.
                Support of the values other(1), volatile(2),
                nonVolatile(3), and permanent(4) is not required."

           OBJECT snmpTargetParamsRowStatus
           SYNTAX INTEGER {
               active(1)
           }
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access to the
                snmpTargetParamsTable is not required.
                Support of the values notInService(2), notReady(3),
                createAndGo(4), createAndWait(5), and destroy(6) is
                not required."

       MODULE -- This Module
           MANDATORY-GROUPS { snmpNotifyGroup }

           OBJECT snmpNotifyTag
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required."

           OBJECT snmpNotifyType
           SYNTAX INTEGER {
               trap(1)
           }
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required.
                Support of the value notify(2) is not required."

           OBJECT snmpNotifyStorageType
           SYNTAX INTEGER {
               readOnly(5)
           }
           MIN-ACCESS    read-only
           DESCRIPTION
               "Create/delete/modify access is not required.
                Support of the values other(1), volatile(2),
                nonVolatile(3), and permanent(4) is not required."

           OBJECT snmpNotifyRowStatus
           SYNTAX INTEGER {
               active(1)
           }
           MIN-ACCESS    read-only



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           DESCRIPTION
               "Create/delete/modify access to the
                snmpNotifyTable is not required.
                Support of the values notInService(2), notReady(3),
                createAndGo(4), createAndWait(5), and destroy(6) is
                not required."

       ::= { snmpNotifyCompliances 1 }

   snmpNotifyBasicFiltersCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
           "The compliance statement for SNMP entities which implement
            SNMP Unconfirmed-Class notifications with filtering, and
            read-create operations on all related tables."
       MODULE SNMP-TARGET-MIB
           MANDATORY-GROUPS { snmpTargetBasicGroup }
       MODULE -- This Module
           MANDATORY-GROUPS { snmpNotifyGroup,
                              snmpNotifyFilterGroup }
       ::= { snmpNotifyCompliances 2 }

   snmpNotifyFullCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
           "The compliance statement for SNMP entities which either
            implement only SNMP Confirmed-Class notifications, or both
            SNMP Unconfirmed-Class and Confirmed-Class notifications,
            plus filtering and read-create operations on all related
            tables."
       MODULE SNMP-TARGET-MIB
           MANDATORY-GROUPS { snmpTargetBasicGroup,
                              snmpTargetResponseGroup }
       MODULE -- This Module
           MANDATORY-GROUPS { snmpNotifyGroup,
                              snmpNotifyFilterGroup }
       ::= { snmpNotifyCompliances 3 }

   snmpNotifyGroup OBJECT-GROUP
       OBJECTS {
           snmpNotifyTag,
           snmpNotifyType,
           snmpNotifyStorageType,
           snmpNotifyRowStatus
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects for selecting which management



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            targets are used for generating notifications, and the
            type of notification to be generated for each selected
            management target."
       ::= { snmpNotifyGroups 1 }

   snmpNotifyFilterGroup OBJECT-GROUP
       OBJECTS {
           snmpNotifyFilterProfileName,
           snmpNotifyFilterProfileStorType,
           snmpNotifyFilterProfileRowStatus,
           snmpNotifyFilterMask,
           snmpNotifyFilterType,
           snmpNotifyFilterStorageType,
           snmpNotifyFilterRowStatus
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects providing remote configuration
            of notification filters."
       ::= { snmpNotifyGroups 2 }

   END

<span class="h3"><a class="selflink" id="section-4.3" href="#section-4.3">4.3</a>.  The Proxy MIB Module</span>

   The SNMP-PROXY-MIB module, which defines MIB objects that provide
   mechanisms to remotely configure the parameters used by an SNMP
   entity for proxy forwarding operations, contains a single table.
   This table, snmpProxyTable, is used to define translations between
   management targets for use when forwarding messages.

<span class="h4"><a class="selflink" id="section-4.3.1" href="#section-4.3.1">4.3.1</a>.  Definitions</span>

   SNMP-PROXY-MIB DEFINITIONS ::= BEGIN

   IMPORTS
       MODULE-IDENTITY,
       OBJECT-TYPE,
       snmpModules
           FROM SNMPv2-SMI

       RowStatus,
       StorageType
           FROM SNMPv2-TC

       SnmpEngineID,
       SnmpAdminString
           FROM SNMP-FRAMEWORK-MIB



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       SnmpTagValue
           FROM SNMP-TARGET-MIB

       MODULE-COMPLIANCE,
       OBJECT-GROUP
           FROM SNMPv2-CONF;

   snmpProxyMIB MODULE-IDENTITY
       LAST-UPDATED "9808040000Z"
       ORGANIZATION "IETF SNMPv3 Working Group"
       CONTACT-INFO
           "WG-email:   snmpv3@lists.tislabs.com
            Subscribe:  majordomo@lists.tislabs.com
                        In message body:  subscribe snmpv3

            Chair:      Russ Mundy
                        Trusted Information Systems
            Postal:     3060 Washington Rd
                        Glenwood MD 21738
                        USA
            EMail:      mundy@tislabs.com
            Phone:      +1-301-854-6889

            Co-editor:  David B. Levi
                        SNMP Research, Inc.
            Postal:     3001 Kimberlin Heights Road
                        Knoxville, TN 37920-9716
            EMail:      levi@snmp.com
            Phone:      +1 423 573 1434

            Co-editor:  Paul Meyer
                        Secure Computing Corporation
            Postal:     2675 Long Lake Road
                        Roseville, MN 55113
            EMail:      paul_meyer@securecomputing.com
            Phone:      +1 651 628 1592

            Co-editor:  Bob Stewart
                        Cisco Systems, Inc.
            Postal:     170 West Tasman Drive
                        San Jose, CA 95134-1706
            EMail:      bstewart@cisco.com
            Phone:      +1 603 654 2686"
       DESCRIPTION
           "This MIB module defines MIB objects which provide
            mechanisms to remotely configure the parameters
            used by a proxy forwarding application."
       REVISION    "9808040000Z"



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       DESCRIPTION "Clarifications, published as
                    <a href="./rfc2573">RFC2573</a>."
       REVISION    "9707140000Z"
       DESCRIPTION "The initial revision, published as <a href="./rfc2273">RFC2273</a>."
       ::= { snmpModules 14 }

   snmpProxyObjects        OBJECT IDENTIFIER ::= { snmpProxyMIB 1 }
   snmpProxyConformance    OBJECT IDENTIFIER ::= { snmpProxyMIB 3 }

   --
   --
   -- The snmpProxyObjects group
   --
   --

   snmpProxyTable OBJECT-TYPE
       SYNTAX      SEQUENCE OF SnmpProxyEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "The table of translation parameters used by proxy forwarder
            applications for forwarding SNMP messages."
       ::= { snmpProxyObjects 2 }

   snmpProxyEntry OBJECT-TYPE
       SYNTAX      SnmpProxyEntry
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "A set of translation parameters used by a proxy forwarder
            application for forwarding SNMP messages.

            Entries in the snmpProxyTable are created and deleted
            using the snmpProxyRowStatus object."
       INDEX { IMPLIED snmpProxyName }
       ::= { snmpProxyTable 1 }

   SnmpProxyEntry ::= SEQUENCE {
       snmpProxyName               SnmpAdminString,
       snmpProxyType               INTEGER,
       snmpProxyContextEngineID    SnmpEngineID,
       snmpProxyContextName        SnmpAdminString,
       snmpProxyTargetParamsIn     SnmpAdminString,
       snmpProxySingleTargetOut    SnmpAdminString,
       snmpProxyMultipleTargetOut  SnmpTagValue,
       snmpProxyStorageType        StorageType,
       snmpProxyRowStatus          RowStatus
   }



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   snmpProxyName OBJECT-TYPE
       SYNTAX      SnmpAdminString (SIZE(1..32))
       MAX-ACCESS  not-accessible
       STATUS      current
       DESCRIPTION
           "The locally arbitrary, but unique identifier associated
            with this snmpProxyEntry."
       ::= { snmpProxyEntry 1 }

   snmpProxyType OBJECT-TYPE
       SYNTAX      INTEGER {
                       read(1),
                       write(2),
                       trap(3),
                       inform(4)
                   }
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The type of message that may be forwarded using
            the translation parameters defined by this entry."
       ::= { snmpProxyEntry 2 }

   snmpProxyContextEngineID OBJECT-TYPE
       SYNTAX      SnmpEngineID
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The contextEngineID contained in messages that
            may be forwarded using the translation parameters
            defined by this entry."
       ::= { snmpProxyEntry 3 }

   snmpProxyContextName OBJECT-TYPE
       SYNTAX      SnmpAdminString
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The contextName contained in messages that may be
            forwarded using the translation parameters defined
            by this entry.

            This object is optional, and if not supported, the
            contextName contained in a message is ignored when
            selecting an entry in the snmpProxyTable."
       ::= { snmpProxyEntry 4 }

   snmpProxyTargetParamsIn OBJECT-TYPE



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       SYNTAX      SnmpAdminString
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object selects an entry in the snmpTargetParamsTable.
            The selected entry is used to determine which row of the
            snmpProxyTable to use for forwarding received messages."
       ::= { snmpProxyEntry 5 }

   snmpProxySingleTargetOut OBJECT-TYPE
       SYNTAX      SnmpAdminString
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object selects a management target defined in the
            snmpTargetAddrTable (in the SNMP-TARGET-MIB).  The
            selected target is defined by an entry in the
            snmpTargetAddrTable whose index value (snmpTargetAddrName)
            is equal to this object.

            This object is only used when selection of a single
            target is required (i.e. when forwarding an incoming
            read or write request)."
       ::= { snmpProxyEntry 6 }

   snmpProxyMultipleTargetOut OBJECT-TYPE
       SYNTAX      SnmpTagValue
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "This object selects a set of management targets defined
            in the snmpTargetAddrTable (in the SNMP-TARGET-MIB).

            This object is only used when selection of multiple
            targets is required (i.e. when forwarding an incoming
            notification)."
       ::= { snmpProxyEntry 7 }

   snmpProxyStorageType OBJECT-TYPE
       SYNTAX      StorageType
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "The storage type of this conceptual row."
       DEFVAL { nonVolatile }
       ::= { snmpProxyEntry 8 }

   snmpProxyRowStatus OBJECT-TYPE



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

            To create a row in this table, a manager must
            set this object to either createAndGo(4) or
            createAndWait(5).

            The following objects may not be modified while the
            value of this object is active(1):
                - snmpProxyType
                - snmpProxyContextEngineID
                - snmpProxyContextName
                - snmpProxyTargetParamsIn
                - snmpProxySingleTargetOut
                - snmpProxyMultipleTargetOut"
       ::= { snmpProxyEntry 9 }

   --
   --
   -- Conformance information
   --
   --

   snmpProxyCompliances OBJECT IDENTIFIER ::=
                                            { snmpProxyConformance 1 }
   snmpProxyGroups      OBJECT IDENTIFIER ::=
                                            { snmpProxyConformance 2 }

   --
   --
   -- Compliance statements
   --
   --

   snmpProxyCompliance MODULE-COMPLIANCE
       STATUS      current
       DESCRIPTION
           "The compliance statement for SNMP entities which include
            a proxy forwarding application."
       MODULE SNMP-TARGET-MIB
           MANDATORY-GROUPS { snmpTargetBasicGroup,
                              snmpTargetResponseGroup }
       MODULE -- This Module
           MANDATORY-GROUPS { snmpProxyGroup }
       ::= { snmpProxyCompliances 1 }



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   snmpProxyGroup OBJECT-GROUP
       OBJECTS {
           snmpProxyType,
           snmpProxyContextEngineID,
           snmpProxyContextName,
           snmpProxyTargetParamsIn,
           snmpProxySingleTargetOut,
           snmpProxyMultipleTargetOut,
           snmpProxyStorageType,
           snmpProxyRowStatus
       }
       STATUS      current
       DESCRIPTION
           "A collection of objects providing remote configuration of
            management target translation parameters for use by
            proxy forwarder applications."
       ::= { snmpProxyGroups 3 }

   END

<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>.  Identification of Management Targets in Notification Originators</span>

   This section describes the mechanisms used by a notification
   originator application when using the MIB module described in this
   document to determine the set of management targets to be used when
   generating a notification.

   A notification originator uses each entry in the snmpNotifyTable to
   find the management targets to be used for generating notifications.
   Each active entry in this table identifies zero or more entries in
   the snmpTargetAddrTable.  Any entry in the snmpTargetAddrTable whose
   snmpTargetAddrTagList object contains a tag value which is equal to a
   value of snmpNotifyTag is selected by the snmpNotifyEntry which
   contains that instance of snmpNotifyTag.  Note that a particular
   snmpTargetAddrEntry may be selected by multiple entries in the
   snmpNotifyTable, resulting in multiple notifications being generated
   using that snmpTargetAddrEntry.

   Each snmpTargetAddrEntry contains a pointer to the
   snmpTargetParamsTable (snmpTargetAddrParams).  This pointer selects a
   set of SNMP parameters to be used for generating notifications.  If
   the selected entry in the snmpTargetParamsTable does not exist, the
   management target is not used to generate notifications.

   The decision as to whether a notification should contain an
   Unconfirmed-Class or a Confirmed-Class PDU is determined by the value
   of the snmpNotifyType object.  If the value of this object is
   trap(1), the notification should contain an Unconfirmed-Class PDU.



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   If the value of this object is inform(2), then the notification
   should contain a Confirmed-Class PDU, and the timeout time and number
   of retries for the notification are the value of
   snmpTargetAddrTimeout and snmpTargetAddrRetryCount.  Note that the
   exception to these rules is when the snmpTargetParamsMPModel object
   indicates an SNMP version which supports a different PDU version.  In
   this case, the notification may be sent using a different PDU type
   ([<a href="#ref-COEX" title="&quot;Coexistence between Version 1, Version 2, and Version 3 of the Internet-standard Network Management Framework&quot;">COEX</a>] defines the PDU type in the case where the outgoing SNMP
   version is SNMPv1).

<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>.  Notification Filtering</span>

   This section describes the mechanisms used by a notification
   originator application when using the MIB module described in this
   document to filter generation of notifications.

   A notification originator uses the snmpNotifyFilterTable to filter
   notifications.  A notification filter profile may be associated with
   a particular entry in the snmpTargetParamsTable.  The associated
   filter profile is identified by an entry in the
   snmpNotifyFilterProfileTable whose index is equal to the index of the
   entry in the snmpTargetParamsTable.  If no such entry exists in the
   snmpNotifyFilterProfileTable, no filtering is performed for that
   management target.

   If such an entry does exist, the value of snmpNotifyFilterProfileName
   of the entry is compared with the corresponding portion of the index
   of all active entries in the snmpNotifyFilterTable.  All such entries
   for which this comparison results in an exact match are used for
   filtering a notification generated using the associated
   snmpTargetParamsEntry.  If no such entries exist, no filtering is
   performed, and a notification may be sent to the management target.

   Otherwise, if matching entries do exist, a notification may be sent
   if the NOTIFICATION-TYPE OBJECT IDENTIFIER of the notification (this
   is the value of the element of the variable bindings whose name is
   snmpTrapOID.0, i.e., the second variable binding) is specifically
   included, and none of the object instances to be included in the
   variable-bindings of the notification are specifically excluded by
   the matching entries.

   Each set of snmpNotifyFilterTable entries is divided into two
   collections of filter subtrees:  the included filter subtrees, and
   the excluded filter subtrees.  The snmpNotifyFilterType object
   defines the collection to which each matching entry belongs.






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   To determine whether a particular notification name or object
   instance is excluded by the set of matching entries, compare the
   notification name's or object instance's OBJECT IDENTIFIER with each
   of the matching entries.  For a notification name, if none match,
   then the notification name is considered excluded, and the
   notification should not be sent to this management target.  For an
   object instance, if none match, the object instance is considered
   included, and the notification may be sent to this management target.
   If one or more match, then the notification name or object instance
   is included or excluded, according to the value of
   snmpNotifyFilterType in the entry whose value of
   snmpNotifyFilterSubtree has the most sub-identifiers.  If multiple
   entries match and have the same number of sub-identifiers, then the
   lexicographically greatest instance of snmpNotifyFilterType among
   those which match determines the inclusion or exclusion.

   A notification name or object instance's OBJECT IDENTIFIER X matches
   an entry in the snmpNotifyFilterTable when the number of sub-
   identifiers in X is at least as many as in the value of
   snmpNotifyFilterSubtree for the entry, and each sub-identifier in the
   value of snmpNotifyFilterSubtree matches its corresponding sub-
   identifier in X.  Two sub-identifiers match either if the
   corresponding bit of snmpNotifyFilterMask is zero (the 'wild card'
   value), or if the two sub-identifiers are equal.

<span class="h2"><a class="selflink" id="section-7" href="#section-7">7</a>.  Management Target Translation in Proxy Forwarder Applications</span>

   This section describes the mechanisms used by a proxy forwarder
   application when using the MIB module described in this document to
   translate incoming management target information into outgoing
   management target information for the purpose of forwarding messages.
   There are actually two mechanisms a proxy forwarder may use, one for
   forwarding request messages, and one for forwarding notification
   messages.

<span class="h3"><a class="selflink" id="section-7.1" href="#section-7.1">7.1</a>.  Management Target Translation for Request Forwarding</span>

   When forwarding request messages, the proxy forwarder will select a
   single entry in the snmpProxyTable.  To select this entry, it will
   perform the following comparisons:

     -  The snmpProxyType must be read(1) if the request is a Read-
        Class PDU.  The snmpProxyType must be write(2) if the request is
        a Write-Class PDU.

     -  The contextEngineID must equal the snmpProxyContextEngineID
        object.




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     -  If the snmpProxyContextName object is supported, it must equal
        the contextName.

     -  The snmpProxyTargetParamsIn object identifies an entry in the
        snmpTargetParamsTable.  The messageProcessingModel,
        securityLevel, security model, and securityName must match the
        values of snmpTargetParamsMPModel,
        snmpTargetParamsSecurityModel, snmpTargetParamsSecurityName, and
        snmpTargetParamsSecurityLevel of the identified entry in the
        snmpTargetParamsTable.

   There may be multiple entries in the snmpProxyTable for which these
   comparisons succeed.  The entry whose snmpProxyName has the
   lexicographically smallest value and for which the comparisons
   succeed will be selected by the proxy forwarder.

   The outgoing management target information is identified by the value
   of the snmpProxySingleTargetOut object of the selected entry.  This
   object identifies an entry in the snmpTargetAddrTable.  The
   identified entry in the snmpTargetAddrTable also contains a reference
   to the snmpTargetParamsTable (snmpTargetAddrParams).  If either the
   identified entry in the snmpTargetAddrTable does not exist, or the
   identified entry in the snmpTargetParamsTable does not exist, then
   this snmpProxyEntry does not identify valid forwarding information,
   and the proxy forwarder should attempt to identify another row.

   If there is no entry in the snmpProxyTable for which all of the
   conditions above may be met, then there is no appropriate forwarding
   information, and the proxy forwarder should take appropriate actions.

   Otherwise, The snmpTargetAddrTDomain, snmpTargetAddrTAddress,
   snmpTargetAddrTimeout, and snmpTargetRetryCount of the identified
   snmpTargetAddrEntry, and the snmpTargetParamsMPModel,
   snmpTargetParamsSecurityModel, snmpTargetParamsSecurityName, and
   snmpTargetParamsSecurityLevel of the identified snmpTargetParamsEntry
   are used as the destination management target.

<span class="h3"><a class="selflink" id="section-7.2" href="#section-7.2">7.2</a>.  Management Target Translation for Notification Forwarding</span>

   When forwarding notification messages, the proxy forwarder will
   select multiple entries in the snmpProxyTable.  To select these
   entries, it will perform the following comparisons:

     -  The snmpProxyType must be trap(3) if the notification is an
        Unconfirmed-Class PDU.  The snmpProxyType must be inform(4) if
        the request is a Confirmed-Class PDU.





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     -  The contextEngineID must equal the snmpProxyContextEngineID
        object.

     -  If the snmpProxyContextName object is supported, it must equal
        the contextName.

     -  The snmpProxyTargetParamsIn object identifies an entry in the
        snmpTargetParamsTable.  The messageProcessingModel,
        securityLevel, security model, and securityName must match the
        values of snmpTargetParamsMPModel,
        snmpTargetParamsSecurityModel, snmpTargetParamsSecurityName, and
        snmpTargetParamsSecurityLevel of the identified entry in the
        snmpTargetParamsTable.

   All entries for which these conditions are met are selected.  The
   snmpProxyMultipleTargetOut object of each such entry is used to
   select a set of entries in the snmpTargetAddrTable.  Any
   snmpTargetAddrEntry whose snmpTargetAddrTagList object contains a tag
   value equal to the value of snmpProxyMultipleTargetOut, and whose
   snmpTargetAddrParams object references an existing entry in the
   snmpTargetParamsTable, is selected as a destination for the forwarded
   notification.

<span class="h2"><a class="selflink" id="section-8" href="#section-8">8</a>.  Intellectual Property</span>

   The IETF takes no position regarding the validity or scope of any
   intellectual property or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; neither does it represent that it
   has made any effort to identify any such rights.  Information on the
   IETF's procedures with respect to rights in standards-track and
   standards-related documentation can be found in <a href="https://www.rfc-editor.org/bcp/bcp11">BCP-11</a>.  Copies of
   claims of rights made available for publication and any assurances of
   licenses to be made available, or the result of an attempt made to
   obtain a general license or permission for the use of such
   proprietary rights by implementors or users of this specification can
   be obtained from the IETF Secretariat.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights which may cover technology that may be required to practice
   this standard.  Please address the information to the IETF Executive
   Director.







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<span class="h2"><a class="selflink" id="section-9" href="#section-9">9</a>.  Acknowledgments</span>

   This document is the result of the efforts of the SNMPv3 Working
   Group.  Some special thanks are in order to the following SNMPv3 WG
   members:

     Harald Tveit Alvestrand (Maxware)
     Dave Battle (SNMP Research, Inc.)
     Alan Beard (Disney Worldwide Services)
     Paul Berrevoets (SWI Systemware/Halcyon Inc.)
     Martin Bjorklund (Ericsson)
     Uri Blumenthal (IBM T.J. Watson Research Center)
     Jeff Case (SNMP Research, Inc.)
     John Curran (BBN)
     Mike Daniele (Compaq Computer Corporation)
     T. Max Devlin (Eltrax Systems)
     John Flick (Hewlett Packard)
     Rob Frye (MCI)
     Wes Hardaker (U.C.Davis, Information Technology - D.C.A.S.)
     David Harrington (Cabletron Systems Inc.)
     Lauren Heintz (BMC Software, Inc.)
     N.C. Hien (IBM T.J. Watson Research Center)
     Michael Kirkham (InterWorking Labs, Inc.)
     Dave Levi (SNMP Research, Inc.)
     Louis A Mamakos (UUNET Technologies Inc.)
     Joe Marzot (Nortel Networks)
     Paul Meyer (Secure Computing Corporation)
     Keith McCloghrie (Cisco Systems)
     Bob Moore (IBM)
     Russ Mundy (TIS Labs at Network Associates)
     Bob Natale (ACE*COMM Corporation)
     Mike O'Dell (UUNET Technologies Inc.)
     Dave Perkins (DeskTalk)
     Peter Polkinghorne (Brunel University)
     Randy Presuhn (BMC Software, Inc.)
     David Reeder (TIS Labs at Network Associates)
     David Reid (SNMP Research, Inc.)
     Aleksey Romanov (Quality Quorum)
     Shawn Routhier (Epilogue)
     Juergen Schoenwaelder (TU Braunschweig)
     Bob Stewart (Cisco Systems)
     Mike Thatcher (Independent Consultant)
     Bert Wijnen (IBM T.J. Watson Research Center)

   The document is based on recommendations of the IETF Security and
   Administrative Framework Evolution for SNMP Advisory Team. Members of
   that Advisory Team were:




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     David Harrington (Cabletron Systems Inc.)
     Jeff Johnson (Cisco Systems)
     David Levi (SNMP Research Inc.)
     John Linn (Openvision)
     Russ Mundy (Trusted Information Systems) chair
     Shawn Routhier (Epilogue)
     Glenn Waters (Nortel)
     Bert Wijnen (IBM T. J. Watson Research Center)

   As recommended by the Advisory Team and the SNMPv3 Working Group
   Charter, the design incorporates as much as practical from previous
   RFCs and drafts. As a result, special thanks are due to the authors
   of previous designs known as SNMPv2u and SNMPv2*:

     Jeff Case (SNMP Research, Inc.)
     David Harrington (Cabletron Systems Inc.)
     David Levi (SNMP Research, Inc.)
     Keith McCloghrie (Cisco Systems)
     Brian O'Keefe (Hewlett Packard)
     Marshall T. Rose (Dover Beach Consulting)
     Jon Saperia (BGS Systems Inc.)
     Steve Waldbusser (International Network Services)
     Glenn W. Waters (Bell-Northern Research Ltd.)

<span class="h2"><a class="selflink" id="section-10" href="#section-10">10</a>.  Security Considerations</span>

   The SNMP applications described in this document typically have
   direct access to MIB instrumentation.  Thus, it is very important
   that these applications be strict in their application of access
   control as described in this document.

   In addition, there may be some types of notification generator
   applications which, rather than accessing MIB instrumentation using
   access control, will obtain MIB information through other means (such
   as from a command line).  The implementors and users of such
   applications must be responsible for not divulging MIB information
   that normally would be inaccessible due to access control.

   Finally, the MIBs described in this document contain potentially
   sensitive information.  A security administrator may wish to limit
   access to these MIBs.

<span class="h2"><a class="selflink" id="section-11" href="#section-11">11</a>.  References</span>

   [<a id="ref-COEX">COEX</a>]      The SNMPv3 Working Group, Frye, R.,Levi, D., Wijnen, B.,
               "Coexistence between Version 1, Version 2, and Version 3
               of the Internet-standard Network Management Framework",
               Work in Progress.



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   [<a id="ref-RFC1157">RFC1157</a>]   Case, J., Fedor, M., Schoffstall, M. and J. Davin,
               "Simple Network Management Protocol", STD 15, <a href="./rfc1157">RFC 1157</a>,
               May 1990.

   [<a id="ref-RFC1213">RFC1213</a>]   McCloghrie, K. and M. Rose, Editors, "Management
               Information Base for Network Management of TCP/IP-based
               internets: MIB-II", STD 17, <a href="./rfc1213">RFC 1213</a>, March 1991.

   [<a id="ref-RFC2578">RFC2578</a>]   McCloghrie, K., Perkins, D. and J. Schoenwaelder,
               "Structure of Management Information Version 2 (SMIv2)",
               STD 58, <a href="./rfc2578">RFC 2578</a>, April 1999.

   [<a id="ref-RFC2579">RFC2579</a>]   McCloghrie, K., Perkins, D. and J.  Schoenwaelder,
               "Textual Conventions for SMIv2", STD 58, <a href="./rfc2579">RFC 2579</a>, April
               1999.

   [<a id="ref-RFC1905">RFC1905</a>]   SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.
               and S.  Waldbusser, "Protocol Operations for Version 2 of
               the Simple Network Management Protocol (SNMPv2)",
               <a href="./rfc1905">RFC1905</a>, January 1996.

   [<a id="ref-RFC1907">RFC1907</a>]   SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.
               and S.  Waldbusser, "Management Information Base for
               Version 2 of the Simple Network Management Protocol
               (SNMPv2)", <a href="./rfc1905">RFC1905</a>, January 1996.

   [<a id="ref-RFC1908">RFC1908</a>]   SNMPv2 Working Group, Case, J., McCloghrie, K., Rose, M.
               and S.  Waldbusser, "Coexistence between Version 1 and
               Version 2 of the Internet-standard Network Management
               Framework", <a href="./rfc1905">RFC1905</a>, January 1996.

   [<a id="ref-RFC2119">RFC2119</a>]   Bradner, S., "Key words for use in RFCs to Indicate
               Requirement Levels", <a href="https://www.rfc-editor.org/bcp/bcp14">BCP 14</a>, <a href="./rfc2119">RFC2119</a>, March 1997.

   [<a id="ref-RFC2571">RFC2571</a>] Harrington, D., Presuhn, R. and B. Wijnen, "An Architecture
               for Describing SNMP Management Frameworks", <a href="./rfc2571">RFC 2571</a>,
               April 1999.

   [<a id="ref-RFC2572">RFC2572</a>]   Case, J., Harrington, D., Presuhn, R. and B. Wijnen,
               "Message Processing and Dispatching for the Simple
               Network Management Protocol (SNMP)", <a href="./rfc2572">RFC 2572</a>, April
               1999.

   [<a id="ref-RFC2575">RFC2575</a>]  Wijnen, B., Presuhn, R. and K. McCloghrie, "View-based
               Access Control Model for the Simple Network Management
               Protocol (SNMP)", <a href="./rfc2575">RFC 2575</a>, April 1999.





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   [<a id="ref-RFC2573">RFC2573</a>] Levi, D. B., Meyer, P. and B. Stewart, "SNMP Applications",
               <a href="./rfc2573">RFC 2573</a>, April 1999.

<span class="h2"><a class="selflink" id="section-12" href="#section-12">12</a>.  Editors' Addresses</span>

   David B. Levi
   SNMP Research, Inc.
   3001 Kimberlin Heights Road
   Knoxville, TN 37920-9716
   U.S.A.

   Phone: +1 423 573 1434
   EMail: levi@snmp.com


   Paul Meyer
   Secure Computing Corporation
   2675 Long Lake Road
   Roseville, MN 55113
   U.S.A.

   Phone: +1 651 628 1592
   EMail: paul_meyer@securecomputing.com


   Bob Stewart
   Cisco Systems, Inc.
   170 West Tasman Drive
   San Jose, CA 95134-1706
   U.S.A.

   Phone: +1 603 654 2686
   EMail: bstewart@cisco.com


















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APPENDIX A - Trap Configuration Example

   This section describes an example configuration for a Notification
   Generator application which implements the snmpNotifyBasicCompliance
   level.  The example configuration specifies that the Notification
   Generator should send notifications to 3 separate managers, using
   authentication and no privacy for the first 2 managers, and using
   both authentication and privacy for the third manager.

   The configuration consists of three rows in the snmpTargetAddrTable,
   and two rows in the snmpTargetTable.

          snmpTargetAddrName         SnmpAdminString,
          snmpTargetAddrTDomain      TDomain,
          snmpTargetAddrTAddress     TAddress,
          snmpTargetAddrTimeout      TimeInterval,
          snmpTargetAddrRetryCount   Integer32,
          snmpTargetAddrTagList      SnmpAdminString,
          snmpTargetAddrParams       SnmpAdminString,
          snmpTargetAddrStorageType  StorageType,
          snmpTargetAddrRowStatus    RowStatus

        * snmpTargetAddrName        = "addr1"
          snmpTargetAddrTDomain     = snmpUDPDomain
          snmpTargetAddrTAddress    = 128.1.2.3/162
          snmpTargetAddrTagList     = "group1"
          snmpTargetAddrParams      = "AuthNoPriv-joe"
          snmpTargetAddrStorageType = readOnly(5)
          snmpTargetAddrRowStatus   = active(1)

        * snmpTargetAddrName        = "addr2"
          snmpTargetAddrTDomain     = snmpUDPDomain
          snmpTargetAddrTAddress    = 128.2.4.6/162
          snmpTargetAddrTagList     = "group1"
          snmpTargetAddrParams      = "AuthNoPriv-joe"
          snmpTargetAddrStorageType = readOnly(5)
          snmpTargetAddrRowStatus   = active(1)

        * snmpTargetAddrName        = "addr3"
          snmpTargetAddrTDomain     = snmpUDPDomain
          snmpTargetAddrTAddress    = 128.1.2.3/162
          snmpTargetAddrTagList     = "group2"
          snmpTargetAddrParams      = "AuthPriv-bob"
          snmpTargetAddrStorageType = readOnly(5)
          snmpTargetAddrRowStatus   = active(1)

        * snmpTargetParamsName                   = "AuthNoPriv-joe"
          snmpTargetParamsMPModel                = 3m



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          snmpTargetParamsSecurityModel          = 3 (USM)
          snmpTargetParamsSecurityName           = "joe"
          snmpTargetParamsSecurityLevel          = authNoPriv(2)
          snmpTargetParamsStorageType            = readOnly(5)
          snmpTargetParamsRowStatus              = active(1)

        * snmpTargetParamsName                   = "AuthPriv-bob"
          snmpTargetParamsMPModel                = 3
          snmpTargetParamsSecurityModel          = 3 (USM)
          snmpTargetParamsSecurityName           = "bob"
          snmpTargetParamsSecurityLevel          = authPriv(3)
          snmpTargetParamsStorageType            = readOnly(5)
          snmpTargetParamsRowStatus              = active(1)

        * snmpNotifyName         = "group1"
          snmpNotifyTag          = "group1"
          snmpNotifyType         = trap(1)
          snmpNotifyStorageType  = readOnly(5)
          snmpNotifyRowStatus    = active(1)

        * snmpNotifyName         = "group2"
          snmpNotifyTag          = "group2"
          snmpNotifyType         = trap(1)
          snmpNotifyStorageType  = readOnly(5)
          snmpNotifyRowStatus    = active(1)

   These entries define two groups of management targets.  The first
   group contains two management targets:

                                first target      second target
                                ------------      -------------
       messageProcessingModel   SNMPv3            SNMPv3
                securityModel   3 (USM)           3 (USM)
                 securityName   "joe"             "joe"
                securityLevel   authNoPriv(2)     authNoPriv(2)
              transportDomain   snmpUDPDomain     snmpUDPDomain
             transportAddress   128.1.2.3/162     128.2.4.6/162

   And the second group contains a single management target:

       messageProcessingModel   SNMPv3
                securityLevel   authPriv(3)
                securityModel   3 (USM)
                 securityName   "bob"
              transportDomain   snmpUDPDomain
             transportAddress   128.1.5.9/162





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<span class="h2"><a class="selflink" id="appendix-B" href="#appendix-B">Appendix B</a>.  Full Copyright Statement</span>

   Copyright (C) The Internet Society (1999).  All Rights Reserved.

   This document and translations of it may be copied and furnished to
   others, and derivative works that comment on or otherwise explain it
   or assist in its implementation may be prepared, copied, published
   and distributed, in whole or in part, without restriction of any
   kind, provided that the above copyright notice and this paragraph are
   included on all such copies and derivative works.  However, this
   document itself may not be modified in any way, such as by removing
   the copyright notice or references to the Internet Society or other
   Internet organizations, except as needed for the purpose of
   developing Internet standards in which case the procedures for
   copyrights defined in the Internet Standards process must be
   followed, or as required to translate it into languages other than
   English.

   The limited permissions granted above are perpetual and will not be
   revoked by the Internet Society or its successors or assigns.

   This document and the information contained herein is provided on an
   "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
   TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
   BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
   HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Acknowledgement

   Funding for the RFC Editor function is currently provided by
   the Internet Society.





















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