Keep business-process-specific data separate?

["Costello, Roger L." <costello@mitre.org>]

Hi Folks,

Suppose I create an XML vocabulary for a "Transportation Task Request." Here's an example: 

In the following instance document I am expressing the desire to be picked up from my home on January 29 at 7 am and dropped off at Logan airport. On my return trip I desire to be picked up at Logan airport on February 4 at 6 pm and dropped off at home:

<Transportation-Request>
    <Departure>
        <Starting-Point>home</Starting-Point>
        <Finishing-Point>Logan airport</Finishing-Point>
        <Datetime>2009-01-29T07:00:00</Datetime>
    </Departure>
    <Return>
        <Starting-Point>Logan airport</Starting-Point>
        <Finishing-Point>home</Finishing-Point>
        <Datetime>2009-02-04T18:00:00</Datetime>
    </Return>
</Transportation-Request>

I create this document then walk it over to my company's transportation office and give it to them. The first thing they do with it is stamp on it the date and time of submission. 


QUESTION

When I create my Transportation Task Request XML vocabulary, should it include a <Submission-Datetime> element? Thus, when I create my instance document, I include an empty <Submission-Datetime> element:

<Transportation-Request>
    <Submission-Datetime></Submission-DateTime>
    <Departure>
        <Starting-Point>home</Starting-Point>
        <Finishing-Point>Logan airport</Finishing-Point>
        <Datetime>2009-01-29T07:00:00</Datetime>
    </Departure>
    <Return>
        <Starting-Point>Logan airport</Starting-Point>
        <Finishing-Point>home</Finishing-Point>
        <Datetime>2009-02-04T18:00:00</Datetime>
    </Return>
</Transportation-Request>

When the transportation office receives the instance document, they fill in the element.

Is this a smart thing to do - include a <Submission-Datetime> element in my Transportation Task Request XML vocabulary?


BUSINESS-PROCESS-SPECIFIC DATA

Recall my objective: create "an XML vocabulary for expressing a transportation task that I want accomplished." 

The <Submission-Datetime> element is not really relevant to my objective. The <Submission-Datetime> element only comes into play when I hand my travel request document to the person at the travel office. That is, the <Submission-Datetime> element is only relevant in this particular business process.

The <Submission-Datetime> element is business process-specific data.


AVOID BUSINESS-PROCESS-SPECIFIC DATA

I think that it's bad to put business-process-specific data with my XML vocabulary.

Do you agree?

My rationale is that in another business process the <Submission-Datetime> element may not be relevant. 

For example, in addition to dropping my document off at the travel office, I also drop a copy off at human resources. The first thing the human resources office does is stamp my name on it. Thus, in this business process, the <Submission-Datetime> element is not needed; rather, a <name> element is needed.

By keeping business-process-specific data decoupled from my XML vocabulary it gives me flexibility to use my XML vocabulary in a variety of business processes.

Do you agree?


WHERE TO PUT THE BUSINESS-PROCESS-SPECIFIC DATA

If I don't put the business-process-specific data with my Transportation Task Request data, where do I put it?


/Roger