According to the Messaging Service spec, the
Acknowledgement element is an optional element that is used by one MHS to
indicate to another MHS that it has received a message (to support the
implementation of reliable messaging). The DeliveryReceipt element is
defined as an optional element that is used by the To Party who received a
message to let the From Party who sent the original message know that the
message was received.
The BPSS spec, on the other hand, defines
Business Signals as application level documents that 'signal' the current
state of the business transaction. "These business signals have specific
business purpose and are separate from lower protocol and transport
signals." Business signals include receipt acknowledgements, acceptance
acknowledgements and exceptions. The structure of signal messages is not
application specific and is defined in Section 9 of the BPSS
spec.
In Section 7.5.11.1 of the CPPA spec, it is
pointed out that the syncReplyMode attribute can take on the possible
values: signalsOnly, responseOnly, signalsAndResponse, and none. Some how,
the CPPA spec is not aware of the Acknowledgment element or the
DeliveryReceipt element defined by the Messaging Service. If syncReplyMode
is set to signalsOnly, responseOnly, or signalsAndResponse, isn't an
Acknowledgement at the MHS level also required to be returned synchronously?
In fact, the meaning of responseOnly is is not clearly defined. If only the
response is to be returned synchronously, how should the MHS level
Acknowledgement and the business level receipt acknowledgement be returned?
Should the MHS level Acknowledgement be returned synchronously and the
business level receipt acknowledgement be simply omitted?
Both the DeliveryReceipt element and the
Receipt Acknowledgement signal message supports non repudiation of receipt.
Without the clear definition of a Message Service Interface, it is very
unclear under what circumstances a To Party will make use of the
DeliveryReceipt element to signal receipt of a message. Why isn't this
subsumed by the Receipt Acknowledgement signal message?
-Arvola
Arvola Chan (arvola@tibco.com)
TIBCO
Software (on loan to RosettaNet)
+1-650-846-5046
(US-Pacific)