Subject: [sacm] Method for expressing the SACM Information Model

From: "Waltermire, David A." <[email-masked]>
Date: Fri, 18 Sep 2015 20:07:45 +0000

On today's Endpoint ID call we discussed the need to settle on a method to describe the SACM information model. While researching information model approaches used by other IETF efforts, I found two existing approaches (provided with an example):

1)      Class-Sub-Class-Attribute (RFC7326)

This approach defines a set of classes, sub classes and attributes for each class.

2)      Object Model (draft-ietf-lmap-information-model)

This approach identifies key objects that are composed of other objects.

We are hoping to come to consensus on what approach to use. In doing so it would be helpful to get answers to the following questions:

1)      What are useful approaches for expressing an information model as described by RFC3444? Are there others beyond the two above?

2)      What approach does the SACM WG prefer?

3)      How do we strike the right balance around specificity without being overly restrictive on data models?

Any opinions on this?

Thanks,
Dave

---

From: "Wolfkiel, Joseph L CIV DISA ID (US)" <[email-masked]>
Date: Fri, 18 Sep 2015 20:14:20 +0000

I'm fond of both UML class diagrams and database E-R diagrams.

Joseph L. Wolfkiel
SCM Engineering Lead
DISA ID52
Work: (301) 225-8820
Gov Cell: (571) 814-8231
[email-masked]

-----Original Message-----
From: sacm [mailto:[email-masked]] On Behalf Of Waltermire, David A.
Sent: Friday, September 18, 2015 4:08 PM
To: [email-masked]
Subject: [sacm] Method for expressing the SACM Information Model

Any opinions on this?

Thanks,
Dave

---

From: "Jim Schaad" <[email-masked]>
Date: Sat, 19 Sep 2015 16:42:28 -0700

I think that this is a difference without a distinction.  I doubt that I
have a preference between the two approaches.

I do have a preference to have some type of formal language that I can do
mechanical transformations and checks on.  From that point of view I am not
really in favor of pictures unless the pictures are generated from a
different input format.

As long as one does not try and specify what the data format is, I am not
sure how one can say that one has overly restricted the data model.  One
should be able to have a fairly direct mapping of information model to data
model so that some information (such as guidance) can be specified using the
IM and then mapped to multiple data models.

Jim

From: sacm [mailto:[email-masked]] On Behalf Of Waltermire, David A.
Sent: Friday, September 18, 2015 1:08 PM
To: [email-masked]
Subject: [sacm] Method for expressing the SACM Information Model

On today's Endpoint ID call we discussed the need to settle on a method to
describe the SACM information model. While researching information model
approaches used by other IETF efforts, I found two existing approaches
(provided with an example):

This approach defines a set of classes, sub classes and attributes for each
class.

We are hoping to come to consensus on what approach to use. In doing so it
would be helpful to get answers to the following questions:

1)      What are useful approaches for expressing an information model as
described by RFC3444? Are there others beyond the two above?

3)      How do we strike the right balance around specificity without being
overly restrictive on data models?

Any opinions on this?

Thanks,

Dave