Pls check some review pieces of: draft-ietf-ipsp-spd-mib-04.txt

["Wijnen, Bert (Bert)" <bwijnen@lucent.com>]

OK, now, during my review, I am running into this object:

   spdGroupContFilter OBJECT-TYPE
       SYNTAX      VariablePointer
       MAX-ACCESS  read-create
       STATUS      current
       DESCRIPTION
           "spdGroupContFilter points to a filter which is evaluated
            to determine whether the spdGroupContComponentName within
            this row should be exercised.  Managers can use this object
            to classify groups of rules or subgroups together in order
            to achieve a greater degree of control and optimization
            over the execution order of the items within the group.  If
            the filter evaluates to false, the rule or subgroup will be
            skipped and the next rule or subgroup will be evaluated
            instead.

            An example usage of this object would be to limit a
            group of rules to executing only when the IP packet
            being process is designated to be processed by IKE.
            This effectively creates a group of IKE specific rules.

            This MIB defines the following tables and scalars which
            may be pointed to by this column.  Implementations may
            choose to provide support for other filter tables or
            scalars as well:

                   diffServMultiFieldClfrTable
                   spdIpOffsetFilterTable
                   spdTimeFilterTable
                   spdCompoundFilterTable
                   spdTrueFilter
                   spdIpsoHeaderFilterTable

            If this column is set to a VariablePointer value which
            references a non-existent row in an otherwise supported
            table, the inconsistentName exception should be
            returned.  If the table or scalar pointed to by the
            VariablePointer is not supported at all, then an
            inconsistentValue exception should be returned."
       DEFVAL { spdTrueFilter }
       ::= { spdGroupContentsEntry 3 }

They use the SYNTAX of VariablePointer, so they can point to a scalar
as well as to a row in a table (or so I suspect because of "tables
and scalars may be pointed to by this column"). 
So here are my questions:
- do we think this is OK? (I think it is).
- do we want them to be more specific about pointing to a table?
  (I think I'd like them to be clear that the Variable Pointer 
   MUST point to the first accessible column in a specific row.
   So in the case of diffServMultiFieldClfrTable the VariablePointer
   must point to an instance of diffServMultiFieldClfrAddrType.)
- Their suggestion to return a inconsistentName is in conflict with
  the for example diffServClfrElementNext in the DIFFSERV-MIB  
  which suggests to return an inconsistentValue (and that one
  is correct according to rfc3415 I think). Is this acceptable?
  (I think not.
   I think I'd rather have them be consistent with the DIFFSERV-MIB.
   So that would mean to switch the use of their inconsistentValue 
   and inconsistentName. In fact, I think that inconsistentName is
   totally impossible given the list of error codes in RFC3416
   sect 4.2.5. If they want to pass back a value for the case 
   described in the last sentence, then maybe resourceUnavailable
   could be used, but I can't say that I like that either.
   I think I don't see how they can differentiate the two cases
   with an errorCode.)
   
  
Comments please.

Bert