RE: [ws-rx] Proposal for i012

["Lei Jin" <ljin@bea.com>]

A request-response MEP used reliably is asynchronous and is basically
composed of two separate one-way MEPs.  Thus, there are really no
differences to the oneway case. (there is nothing normally flowing back
on the http response)  

If there is an AcksTo address on the source side that is reachable from
the destination, then use that address.   Otherwise, use the not-allowed
EPR for AcksTo which means you can retrieve the Acks through AcksRequest
messages.

Lei

> -----Original Message-----
> From: Anish Karmarkar [mailto:Anish.Karmarkar@oracle.com] 
> Sent: Thursday, August 25, 2005 10:24 AM
> To: Lei Jin
> Cc: Marc Goodner; ws-rx@lists.oasis-open.org; Christopher B Ferris
> Subject: Re: [ws-rx] Proposal for i012
> 
> 
> Hi Lei,
> 
> How does your proposal address the scenario where:
> HTTP is being used, there aren't any intermediaries, it is a 
> request-response WSDL MEP, and the acks are to be sent using the HTTP 
> response (backchannel).
> 
> In such a case, what should the value of the [address] property of 
> AcksTo EPR be?
> 
> -Anish
> --
> 
> Lei Jin wrote:
> > I disagree.  Here is a use case that shows a problem with 
> an anonymous
> > AcksTo.
> >  
> > Node A  --->  Intermediary ---> Node B
> >  
> > Node A tries to send messages reliably to Node B.  For simplicity, 
> > let's
> > assume these are all oneway messages.  Node A establishes a 
> reliable 
> > sequence with an anonymous AcksTo and starts to send messages.  The 
> > messages first go through the Intermediary which has B's WSDL and 
> > figures out these are oneway messages.  So it decides to 
> send back a 
> > http 202 to A and close the connection before forwarding 
> the message on 
> > to Node B.  Now Node B gets the message and wants to send 
> back an Ack 
> > synchronously (due to the anonymous Ack).  But it can't 
> send the Ack 
> > since the connection between Node A and the Intermediary is 
> already closed.
> >  
> > Basically the problem is that the introduction of anonymous AcksTo
> > converts a oneway MEP into a two-way MEP.  In order for it 
> to work, all 
> > intermediaries will need to be WSRM aware and keep 
> connections open in 
> > case synchronous acks need to be sent back.
> >  
> > Proposal:
> >  
> > * Specifically call out that the anonymous IRI is not to be used in 
> > AcksTo.
> > * AcksTo may take on the value of the "not allowed" IRI, 
> >  "_http://www.w3.org/@@@@/@@/addressing/none_";.  When 
> AcksTo takes on 
> > this value, acknowledgement will only be sent back in response to 
> > AckRequest messages.
> >  
> > Lei
> >  
> > 
> >     -----Original Message-----
> >     *From:* Marc Goodner [mailto:mgoodner@microsoft.com]
> >     *Sent:* Tuesday, August 23, 2005 3:16 PM
> >     *To:* ws-rx@lists.oasis-open.org; Lei Jin; Christopher B Ferris
> >     *Subject:* [ws-rx] Proposal for i012
> > 
> >     I believe Chris Ferris had made a similar proposal 
> earlier but in
> >     the interest of a +1 and trying to move this along I'll 
> make a more
> >     formal proposal.
> > 
> >      
> > 
> >     Proposal:
> > 
> >     WS-RM was designed to be used with WS-Addressing in which the
> >     behavior of the anonymous URI is defined as an address 
> in an EPR.
> >     There is no requirement that the anonymous URI must be used and
> >     there are valid applications of it, therefore this 
> issue should be
> >     closed with no action
> > 
>