RE: Methods in the NIM requirements

["Andrea Westerinen" <andreawest@mindspring.com>]

That is a very valid question - "What does the DMTF's MappingStrings
qualifier mean?" This qualifier indicates where data could be mapped to/from
the CIM property.  It does not specify the algorithm for the mapping - only
that logically similar data is defined.

Andrea

> -----Original Message-----
> From: owner-nim@ops.ietf.org [mailto:owner-nim@ops.ietf.org]On Behalf Of
> Juergen Schoenwaelder
> Sent: Monday, May 15, 2000 1:02 AM
> To: andreawest@mindspring.com
> Cc: nim@ops.ietf.org
> Subject: Re: Methods in the NIM requirements
>
>
>
> >>>>> Andrea Westerinen writes:
>
> Andrea> I know that Juergen said that he didn't want to discuss this -
> Andrea> but why bring up an example and then say "don't discuss this"?
> Andrea> The DMTF teams (both Device and Networks) really did give some
> Andrea> thought to the Speed property in CIM_NetworkAdapter.  Here is
> Andrea> the background:
>
> Andrea> 1.  "Speed" was modeled as a uint64 since it was discussed
> Andrea> that maximum growth range should be allowed and that units
> Andrea> should stay "bps" for consistency with the IETF MIB.  2.  If
> Andrea> the Speed value actually fits in a uint32, then the mapping is
> Andrea> clear.  If the Speed is greater than a uint32 with units of
> Andrea> bps, then reality can't be reflected in RFC1213's attribute.
> Andrea> 3.  The goal was to map both the MIB and DMI, where DMI
> Andrea> defined the property with units of Mbps.
>
> So the question which may be important in this context is what an
> expression like
>
> >          MappingStrings {"MIB.IETF|RFC1213-MIB.ifSpeed",
> >                "MIF.DMTF|Network Adapter 802 Port|001.5"}
>
> really means if both referenced definitions are not really the same as
> the CIM definition of Speed. (BTW, IF-MIB (right now RFC 2233) defines
> ifHighSpeed which is again different from CIM's definition of Speed
> (mostly due to SMIv2 shortcomings).
>
> Once again, it was not my goal to discuss whether the CIM definition
> of Speed makes sense or not. What I was trying to point out is that
> mappings even in this simple case turn out to be not that simple.
> (And they may actually mislead implementors who do not carefully study
> the subtle differences to do the wrong thing.)
>
> /js
>