rfc2982.txt

著名的RFC文档,其中有一些文档是已经翻译成中文的的.

     if more than one object in the same expression is wildcarded
     in this way, they all must be objects where that portion of
     the instance is the same.  In other words, all objects may be
     in the same SEQUENCE or in different SEQUENCEs but with the
     same semantic index value (e.g., a value of ifIndex)
     for the wildcarded portion."
    ::= { expDefine 3 }

expObjectEntry OBJECT-TYPE
    SYNTAX      ExpObjectEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
     "Information about an object.  An application uses
     expObjectEntryStatus to create entries in this table while
     in the process of defining an expression.

     Values of read-create objects in this table may be
     changed at any time."
    INDEX       { expExpressionOwner, expExpressionName, expObjectIndex }
    ::= { expObjectTable 1 }

ExpObjectEntry ::= SEQUENCE {
    expObjectIndex                     Unsigned32,
    expObjectID                        OBJECT IDENTIFIER,
    expObjectIDWildcard                TruthValue,



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    expObjectSampleType                INTEGER,
    expObjectDeltaDiscontinuityID      OBJECT IDENTIFIER,
    expObjectDiscontinuityIDWildcard   TruthValue,
    expObjectDiscontinuityIDType       INTEGER,
    expObjectConditional               OBJECT IDENTIFIER,
    expObjectConditionalWildcard       TruthValue,
    expObjectEntryStatus               RowStatus
}

expObjectIndex OBJECT-TYPE
    SYNTAX      Unsigned32 (1..4294967295)
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
     "Within an expression, a unique, numeric identification for an
     object.  Prefixed with a dollar sign ('$') this is used to
     reference the object in the corresponding expExpression."
    ::= { expObjectEntry 1 }

expObjectID OBJECT-TYPE
    SYNTAX      OBJECT IDENTIFIER
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
     "The OBJECT IDENTIFIER (OID) of this object.  The OID may be
     fully qualified, meaning it includes a complete instance
     identifier part (e.g., ifInOctets.1 or sysUpTime.0), or it
     may not be fully qualified, meaning it may lack all or part
     of the instance identifier.  If the expObjectID is not fully
     qualified, then expObjectWildcard must be set to true(1).
     The value of the expression will be multiple
     values, as if done for a GetNext sweep of the object.

     An object here may itself be the result of an expression but
     recursion is not allowed.

     NOTE:  The simplest implementations of this MIB may not allow
     wildcards."
    ::= { expObjectEntry 2 }

expObjectIDWildcard  OBJECT-TYPE
    SYNTAX      TruthValue
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
        "A true value indicates the expObjecID of this row is a wildcard
        object. False indicates that expObjectID is fully instanced.
        If all expObjectWildcard values for a given expression are FALSE,



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        expExpressionPrefix will reflect a scalar object (i.e. will
        be 0.0).

        NOTE:  The simplest implementations of this MIB may not allow
        wildcards."
    DEFVAL      { false }
    ::= { expObjectEntry 3 }

expObjectSampleType OBJECT-TYPE
    SYNTAX      INTEGER { absoluteValue(1), deltaValue(2),
                          changedValue(3) }
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
     "The method of sampling the selected variable.

     An 'absoluteValue' is simply the present value of the object.

     A 'deltaValue' is the present value minus the previous value,
     which was sampled expExpressionDeltaInterval seconds ago.
     This is intended primarily for use with SNMP counters, which are
     meaningless as an 'absoluteValue', but may be used with any
     integer-based value.

     A 'changedValue' is a boolean for whether the present value is
     different from the previous value.  It is applicable to any data
     type and results in an Unsigned32 with value 1 if the object's
     value is changed and 0 if not.  In all other respects it is as a
     'deltaValue' and all statements and operation regarding delta
     values apply to changed values.

     When an expression contains both delta and absolute values
     the absolute values are obtained at the end of the delta
     period."
    DEFVAL      { absoluteValue }
    ::= { expObjectEntry 4 }

sysUpTimeInstance OBJECT IDENTIFIER ::= { sysUpTime 0 }

expObjectDeltaDiscontinuityID OBJECT-TYPE
    SYNTAX      OBJECT IDENTIFIER
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
     "The OBJECT IDENTIFIER (OID) of a TimeTicks, TimeStamp, or
     DateAndTime object that indicates a discontinuity in the value
     at expObjectID.




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     This object is instantiated only if expObjectSampleType is
     'deltaValue' or 'changedValue'.

     The OID may be for a leaf object (e.g. sysUpTime.0) or may
     be wildcarded to match expObjectID.

     This object supports normal checking for a discontinuity in a
     counter.  Note that if this object does not point to sysUpTime
     discontinuity checking must still check sysUpTime for an overall
     discontinuity.

     If the object identified is not accessible no discontinuity
     check will be made."
    DEFVAL      { sysUpTimeInstance }
    ::= { expObjectEntry 5 }

expObjectDiscontinuityIDWildcard OBJECT-TYPE
     SYNTAX      TruthValue
     MAX-ACCESS  read-create
     STATUS      current
     DESCRIPTION
     "A true value indicates the expObjectDeltaDiscontinuityID of
     this row is a wildcard object.  False indicates that
     expObjectDeltaDiscontinuityID is fully instanced.

     This object is instantiated only if expObjectSampleType is
     'deltaValue' or 'changedValue'.

     NOTE:  The simplest implementations of this MIB may not allow
     wildcards."
    DEFVAL      { false }
     ::= { expObjectEntry 6 }

expObjectDiscontinuityIDType OBJECT-TYPE
     SYNTAX      INTEGER { timeTicks(1), timeStamp(2), dateAndTime(3) }
     MAX-ACCESS  read-create
     STATUS      current
     DESCRIPTION
     "The value 'timeTicks' indicates the expObjectDeltaDiscontinuityID
     of this row is of syntax TimeTicks.  The value 'timeStamp' indicates
     syntax TimeStamp.  The value 'dateAndTime indicates syntax
     DateAndTime.

     This object is instantiated only if expObjectSampleType is
     'deltaValue' or 'changedValue'."
    DEFVAL      { timeTicks }
     ::= { expObjectEntry 7 }




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expObjectConditional OBJECT-TYPE
    SYNTAX      OBJECT IDENTIFIER
    MAX-ACCESS  read-create
    STATUS      current
    DESCRIPTION
     "The OBJECT IDENTIFIER (OID) of an object that overrides
     whether the instance of expObjectID is to be considered
     usable.  If the value of the object at expObjectConditional
     is 0 or not instantiated, the object at expObjectID is
     treated as if it is not instantiated.  In other words,
     expObjectConditional is a filter that controls whether or
     not to use the value at expObjectID.

     The OID may be for a leaf object (e.g. sysObjectID.0) or may be
     wildcarded to match expObjectID.  If expObject is wildcarded and
     expObjectID in the same row is not, the wild portion of
     expObjectConditional must match the wildcarding of the rest of
     the expression.  If no object in the expression is wildcarded
     but expObjectConditional is, use the lexically first instance
     (if any) of expObjectConditional.

     If the value of expObjectConditional is 0.0 operation is
     as if the value pointed to by expObjectConditional is a
     non-zero (true) value.

     Note that expObjectConditional can not trivially use an object
     of syntax TruthValue, since the underlying value is not 0 or 1."
    DEFVAL      { zeroDotZero }
    ::= { expObjectEntry 8 }

 expObjectConditionalWildcard  OBJECT-TYPE
     SYNTAX      TruthValue
     MAX-ACCESS  read-create
     STATUS      current
     DESCRIPTION

     "A true value indicates the expObjectConditional of this row is
     a wildcard object. False indicates that expObjectConditional is
     fully instanced.

     NOTE: The simplest implementations of this MIB may not allow
     wildcards."
    DEFVAL      { false }
     ::= { expObjectEntry 9 }

expObjectEntryStatus OBJECT-TYPE
    SYNTAX      RowStatus
    MAX-ACCESS  read-create



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    STATUS      current
    DESCRIPTION
     "The control that allows creation/deletion of entries.

     Objects in this table may be changed while
     expObjectEntryStatus is in any state."
    ::= { expObjectEntry 10 }

--
-- Expression Value Table
--

expValueTable OBJECT-TYPE
    SYNTAX      SEQUENCE OF ExpValueEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
     "A table of values from evaluated expressions."
    ::= { expValue 1 }

expValueEntry OBJECT-TYPE
    SYNTAX      ExpValueEntry
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
     "A single value from an evaluated expression.  For a given
     instance, only one 'Val' object in the conceptual row will be
     instantiated, that is, the one with the appropriate type for
     the value.  For values that contain no objects of
     expObjectSampleType 'deltaValue' or 'changedValue', reading a
     value from the table causes the evaluation of the expression
     for that value.  For those that contain a 'deltaValue' or
     'changedValue' the value read is as of the last sampling
     interval.

     If in the attempt to evaluate the expression one or more
     of the necessary objects is not available, the corresponding
     entry in this table is effectively not instantiated.

     To maintain security of MIB information, when creating a new
     row in this table, the managed system must record the security
     credentials of the requester.  These security credentials are
     the parameters necessary as inputs to isAccessAllowed from
     [RFC2571]. When obtaining the objects that make up the
     expression, the system must (conceptually) use isAccessAllowed to
     ensure that it does not violate security.

     The evaluation of that expression takes place under the



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     security credentials of the creator of its expExpressionEntry.

     To maintain security of MIB information, expression evaluation must
     take place using security credentials for the implied Gets of the
     objects in the expression as inputs (conceptually) to
     isAccessAllowed from the Architecture for Describing SNMP
     Management Frameworks.  These are the security credentials of the
     creator of the corresponding expExpressionEntry."
    INDEX       { expExpressionOwner, expExpressionName,
                  IMPLIED expValueInstance }
    ::= { expValueTable 1 }

ExpValueEntry ::= SEQUENCE {
    expValueInstance          OBJECT IDENTIFIER,
    expValueCounter32Val      Counter32,
    expValueUnsigned32Val     Unsigned32,
    expValueTimeTicksVal      TimeTicks,
    expValueInteger32Val      Integer32,
    expValueIpAddressVal      IpAddress,
    expValueOctetStringVal    OCTET STRING,
    expValueOidVal            OBJECT IDENTIFIER,
    expValueCounter64Val      Counter64
}

expValueInstance OBJECT-TYPE
    SYNTAX      OBJECT IDENTIFIER
    MAX-ACCESS  not-accessible
    STATUS      current
    DESCRIPTION
     "The final instance portion of a value's OID according to
     the wildcarding in instances of expObjectID for the
     expression.  The prefix of this OID fragment is 0.0,
     leading to the following behavior.

     If there is no wildcarding, the value is 0.0.0.  In other
     words, there is one value which standing alone would have
     been a scalar with a 0 at the end of its OID.

     If there is wildcarding, the value is 0.0 followed by
     a value that the wildcard can take, thus defining one value
     instance for each real, possible value of the wildcard.
     S