service and action

Looking at the Message Service Spec, version 1.0, I am having trouble
understanding how each Party knows what to put into the service and action
elements of the message header when it builds a message to send (service
and action refer to the software that processes the message at the
destination.  I realize that this is somewhat implementation and may
involve transformations at the message recipient dependent but the bottom
line is that each party has to know what to put into these elements.  Is it
assumed that this information comes from the Process Specification document
(BPSS instance document) that the CPA points to?  Did anyone check that the
assumption is correct?

Regards,
Marty

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Martin W. Sachs
IBM T. J. Watson Research Center
P. O. B. 704
Yorktown Hts, NY 10598
914-784-7287;  IBM tie line 863-7287
Notes address:  Martin W Sachs/Watson/IBM
Internet address:  mwsachs @ us.ibm.com
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