RE: [ws-rx] AS need for ordered delivery?

Chris:

“RM enables InOrder "delivery" (whatever that means).”

That is my point too: We need to think about what “in order delivery” *really* means or implies and whether it belongs in our spec.

I do not think it actually means a guarantee that all messages will be “delivered in order” as it implies. I think that it really implies the messages delivered are ordered via a sequence marker which allows any destination to understand the order in which the sender intended them to be processed. Delivery is really irrelevant. Think about this for a bit:

RMS sends RMD 1,2,3 and 5.

RMD sends ack for 1,2,3 and 5

RMS re-transmits 4

RMD acks 4

Note that message 4 was not delivered in order to RMD. So what does this imply the RMD must do with the messages WRT the AD?

Can the RMD send along 1,2,3 and 5 to the AD with some flag stating “please note that there is a message 4 and it is missing”?

Does it explicitly have to wait until 4 arrives then send 4 and follow that with 5?

What we really are wanting to do is to ensure that when messages arrives at the RMD, they contain all the information so that the ordering intentions of the RMS can be re-created. What the RMD does then to assure the ultimate destination(s) have access to this information is moot for this spec. The mechanism for such is explicitly stated as out of scope in our charter.

So what does “in order delivery” really mean and does it even belong in the WS-RX TC.

Duane

ws-rx message