Marty:
My assumption has been that all of the attributes under the proposed
MessagingCharacteristics element in the CPA have essentially "per message"
semantics. The corresponding attribute/element must be set in the SOAP
message in order to elicit the expected behavior. The receiver is required
to verify that the behavior(s) requested in the incoming message is/are
consistent with agreements documented in the CPA.
When intermediaries that are not aware of the CPA are involved, the only way
to get them to participate in the reliable messaging behavior is to have an
AckRequested element in the SOAP envelope to request that behavior.
Specifically, I am referring to the use of intermediate Acks, and the
retransmission on intermediate Ack timeout from the next intermediary.
This treatment is also consistent with the use of the SyncReply element,
which exists only for the benefit of intermediaries.
Regards,
-Arvola