<Krishna Sankar>
Yep. Sequencing is a little strict and does not bring out the concept very
well. I am using the term "ordering" (which means temporal ordering) as the
term for this when talking with the business. Also there is the explicit
ordering (means there is some information in the XML document to reflect
ordering) and implicit (there is no ordering specific information in the XML
document) ordering. Sequence Numbers and timeStamp are two methods to
achieve explicit ordering.
</Krishna Sankar>
The ordering or choreography relationships that are most interesting
to me are those that have clear business logic behind them,
often in the form of pre and post conditions.
For example, a prepayment business collaboration contract
would mean the payment must arrive before the delivery.
Economic events that fulfill commitments would be expected
to occur after their respective commitments.
Or another way, the states of a negotiation could be
choreographed by a state machine.
One question on terminology: "choreography" implies (to me)
the deliberate ordering of events. "Ordering" might also mean
a corrected sequence when the received messages arrive
out of their causal order. (Or would you use the same
term in either case, Tony Weida?)
Thanks for the conversation,
Bob Haugen
