Re: One issue pertaining to Arvola response to Marty to Hima onv1question4

[christopher ferris <chris.ferris@east.sun.com>]

Arvola,

Please see below.

Cheers,

Chris

Dale Moberg wrote:
> 
> >4) What are the endpoints used for Ping, Pong, StatusRequest,
> >StatusRepsonse, DeliveryReceipt, Acknowledgment, MessageError
> >Ping -> "request"?
> >Pong -> "response"?
> >StatusRequest -> "request"?
> >StatusResponse -> "response"?
> >Acknowledgement -> "response"?
> >DeliveryReceipt -> "response"?
> >MessageError (ErrorList)-> "error"?
> >
> >MWS: Any of the above which are application-defined may be associated
> >with whatever endpoints the business wants to use.  The ones you
> suggest
> >are one possibility.  Signals and MSH to MSH messages are outside the
> >scope of the CPA.  Addressing of those messages should be defined in
> >the Message Service specification.
> >
> 
> <ac>
> I believe Signals, as they are defined in BPSS, are considered
> application
> level messages. The CPP/A attribute syncReplyMode can take on values
> like signalsOnly, signalsAndResponse, etc. Therefore, I don't think they
> are outside of the scope of the CPA. Intermediate acknowledgements
> and end-to-end delivery receipts, used to implement the exactly once

"exactly once"? The TR&P team specifically excluded this level of
service from consideration as it was felt that it was too complicated. 
OnceAndOnlyOnce is not the same as ExactlyOnce.
ExactlyOnce is for the likes of IBM's MQSeries that can offer
this level of service, at a cost.

> delivery semantics of reliable messaging are purely MSH to MSH, but
> they can also be piggybacked on top of application level messages.
> I particularly would like to see some clarifications on the
> circumstances
> under which piggybacking can be done in conjunction with synchronous
> and asynchronous reply modes.
> </ac>
> 
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