[Css-csts] Service Specification normative dependency on Guidelines

[John Pietras]

CSTSWG colleagues ---
The Monitored Data CSTS draft Red Book includes the Guidelines Magenta Book in the references, and makes one reference to that document - in section 3.2.1, where it is referenced as what to read in order to understand the Monitored Data Transfer Services Procedures table. As currently written, the MD-CSTS specification requires that the reader have access to the Guidelines in order to interpret the contents of the table. This implies that that the Guidelines will have to be available at the same time that the MD-CSTS specification is published. To my understanding, the Guidelines book might need considerable updating before it is ready for publication, and may require resources that the CSTSWG does not currently have available. Ideally, the MD-CSTS and other near-term CSTS specifications (such as TD-CSTS) would be published without reliance on the publication of the Guidelines book.

The Guidelines book contains (at least) two kinds of information:

1.       Guidelines for _writing_ a CSTS specification and

2.       How to interpret the terse specifications in order to implement them.

The first kind of information is important only to those writing CSTS specifications. As long as this information is available through "corporate memory" within the CSTSWG, and as long as it is only the CSTSWG that will be writing CSTS specifications,  it's not really necessary to document these kinds of guidelines in a formal document. The usefulness of such guidelines becomes evident over the longer term, when perhaps more (and new) people will be attempting to write CSTS specifications.

The second kind of guidelines are needed immediately, because they provide the necessary information to allow implementers to read the CSYS specifications. These implementers will not in general have had any presence in the CSTSWG and so the interpretive material must be formally documented

The "how to read" guidelines are essentially available today, but the "how to write" guidelines may require considerable work to account for the many new ideas (Functional Resources, etc.) that have been introduced into CSTS since the Guidelines were last worked upon.

So here are the options that I see for addressing the issue such that we can get the early CSTS specifications (such as MD-CSTS) published as soon as possible.

A.      Increase the priority on completing the Guidelines book as currently defined, so that it be published ASAP. As stated above, I think this will mostly involve fleshing out and updating the "how to write" aspects, which really aren't important to the readers of the CSTS specifications.

B.      Extract the "how to read" material from the current Guidelines, such that the Guidelines document itself can be the Recommended Practice for _writing_ CSTS specifications but no more than an informative reference for the specifications that are written in accordance with it. Completion of the Guidelines book itself can stay off the critical path. Publish the "how to read" material in one of the following ways:

1)      Incorporate it directly into the service specifications themselves. This will make those specifications each a bit bigger than they would otherwise be (and more repetitive, which is something that we have been trying to avoid with CSTS), but it would allow each service specification be a bit more self-standing;

2)      Create a separate "How to Read CSTS Specifications" Green or Yellow Book. Such a book could probably be assembled faster than it would take to update the "how to write" parts of the Guidelines book.

3)      Add the "how to read" material to the CSTS SFW itself. The only advantage that I see to this option (relative to a separate Green or Yellow book) is that it doesn't increase the total document count compared to what we have today. However, it would really stretch the scope of the Framework book, and for that reason I'm not much in favor of it.

C.      Adopt an evolutionary approach, where the initial CSTS specifications include the "how to read" material and thus have no normative dependency on the Guidelines. When the Guidelines book is eventually published, reference the Guidelines book for the "how to read" material in CSTS specification that are published thereafter.

I welcome any comments that you may have.

Best regards,
John

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