ebBP 5/2/2005: Multiple Joins on a Fork (Followup to 19 April 2005)

["Monica J. Martin" <Monica.Martin@Sun.COM>]

As we discussed at our last meeting 19 April (in detail), here is the 
original question from Kenji Nagahashi regarding multiple joins and forks:

    Can single fork apply to multiple joins?  I think this is possible
    but we have not discussed this case. Do we address this in the
    section on Fork and Join as an edge-case? Corresponding text doesn't
    address it either way so are we silent on this?

        "It MUST only be used in the case where all outgoing transitions
    from the Fork have incoming transitions to the Join."

Discussion:

    * Multiple Joins are allowed for a Fork, without making its behavior
      implementation dependent. In general, semantics of Fork are clear
      enough: multiple dependencies to enable next activity. BSI must
      wait until all (or any) of incoming transitions are executed.
    * Combining XOR Forks and multiple Joins, author can easily create
      unsatisfiable Fork. This is addressed in the table 7 in the
      Committee Specification.
    * ebBP can be configured eBusiness gateway to automatically
      establish interpretable collaboration between trading partners. It
      could specify this interface. The technical specification is much
      more refined.

Resolution: Address any open questions on fork-join in a subsequent 
version as Table 7 is clear to the level of definition. Reference 
meeting notes: 
http://www.oasis-open.org/apps/org/workgroup/ebxml-bp/document.php?document_id=12396

If anyone has subsequent questions, please bring them up in our call 
tomorrow. Thanks.