RE: [ebxml-msg] some issues affecting header design

From
Jacques Durand <>
Date
2004-09-20T23:25:33+00:00
ID
Thread
RE: [ebxml-msg] some issues affecting header design
Title: RE: [ebxml-msg] some issues affecting header design

Doug:

Let me try to cut short on commenting on a previous unclear comment..:

I believe we'll need an ebMS message ID in addition to the RM ID,

even if an implementation could weasel its way out - which I am not even sure yet.

My turn to be puzzled by your fisrt paragraph below: 

Because RM-Replies are only visible to RMPs and are correlated by these to reqeust(s) based on RM IDs.

I guess by RM-Reply you mean [business] response that uses "response" reply pattern?

So the use of RefToMessageId seems rather orthogonal to this - it would allow for correlating in ebMS

where RM headers are no longer visible.

Jacques

-----Original Message-----

From: Doug Bunting [mailto:]

Sent: Monday, September 20, 2004 2:32 PM

To: Jacques Durand

Cc: 'Jeff Turpin'; 

Subject: Re: [ebxml-msg] some issues affecting header design

Jacques,

I am not sure I understand your last comments below.  In WS-R, correlation 

of the response using the "layer below" is unnecessary[1] in general. 

While that may be the most obvious way to do some correlations, RM-Reply 

information MUST be correlated with the original message using the 

RefToMessageId mechanism because multiple RM-Replies may always be grouped 

together.

It is true, the business payload might be correlated using the underlying 

protocol.  This results in a bizarre architectural layering: SOAP 

extensions supporting the "infrastructure and the underlying protocol 

supporting the "application".  It is also unspecified in the WS-Reliability 

specification.  Other mechanisms (such as identifying the relevant request 

in the first RM-Reply) are possible through out-of-band agreement.

In short, "supported by the layer below" does not immediately imply 

"necessary".  Could you please explain your thinking more completely?

thanx,

        doug

[1] ... as in REQUIRED in the RFC 2119 sense

On 20-Sep-04 11:58, Jacques Durand wrote:

>     5. Message identity:

>     do we need an identity in addition to RM identity. That is still

>     unclear.

>     Implementation aspects (which MSH+RMP architectures will/not handle

>     a single indentity?) need be considered.

> 

>     [JWT] Although multiple identities(MessageIds) in the Message would

>     seem redundant and confusing, it might be necessary to correlate

>     messages within an MEP at the MSH level. However, you are correct,

>     this is still unclear, and arguments can be made for and against

>     this. We definitely need to discuss this further.

>     [Jacques Durand] I see one case where the MSH needs to correlate

>     Response wirth Request . In case this is implemented with SOAP

>     request-response MEP, we can assume the correlation is supported by

>     the layer below. But depending on what kind of duplicate scenarios

>     we expect, and whether we still want this correlation even for

>     asynchronous ebMS Request-response MEPs, we may need a distinct ebMS

>     ID. It also depends on the role we expect from RefToMessageId.

> 

>      

> 

>     Jacques