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RE: Layers in the WSA (was RE: [Fwd: UN/CEFACT TMG Releases e-Bus ines s Architecture Technical Specification for Public Review])

From: Assaf Arkin <arkin@intalio.com>
Date: Wed, 12 Feb 2003 22:01:33 -0800
To: "Burdett, David" <david.burdett@commerceone.com>, "'Duane Nickull'" <duane@xmlglobal.com>, <www-ws-arch@w3.org>
Cc: <www-ws-arch@w3.org>
Message-ID: <IGEJLEPAJBPHKACOOKHNEEAMDDAA.arkin@intalio.com>
RE: Layers in the WSA (was RE: [Fwd: UN/CEFACT TMG Releases e-Busines s
Architecture Technical Specification for Public Review])On the other hand,
there will be use cases where there are long-standing business relationships
with repeat business where negotiating and making agreements in advance (as
ebXML does) makes complete sense.

Can we say that in this case the message has to contain a reference to some
agreement and the message gets processed subject to that agreement?

For example, you can have a service level agreement that need to be
pre-negotiated and all messages have to carry the SLA number to be processed
and the SLA can be started and managed by some WSDL operation. There is no
need to negotiate messaging-level agreement, and the negotiation of another
agreement could be in itself a service.

Just like a bank account, where I need to reference the account number when
I deposit or withdraw money (essentially my SLA), and I can also have
operations for creating and closing an account, but I don't need to
negotiate any messaging agreement with my bank. I can access my bank account
online from any computer that has support for the requested protocol (in my
case HTTPS).

arkin

  So my take would be:
  1. The messaging layer should allow support for the set of additional
features required (e.g. security, reliability, conversations, etc)

  2. Use of the features in a message either separately or together should
be identified by extensions in the SOAP headers so that the recipient of the
message can determine what the sender expects them to do with the message.

  3. The specification, ngotiation, and enforcement of agreements as in
ebXML should be possible, but as a layer on top.

  Hope this helps.

  David

  -----Original Message-----
  From: Duane Nickull [mailto:duane@xmlglobal.com]
  Sent: Wednesday, February 12, 2003 1:40 PM
  To: www-ws-arch@w3.org
  Cc: www-ws-arch@w3.org
  Subject: Re: Layers in the WSA (was RE: [Fwd: UN/CEFACT TMG Releases
  e-Busines s Architecture Technical Specification for Public Review])






  Champion, Mike wrote:
  =
  > Roger raises a very important point, IMHO. Does anyone who is involved
in
  > ebXML(or any other company/ organization who has this view of the world)
  > want to make a case for the WSA conception of a messaging layer  having
to
  > understand and enforce business-level rules?
   >>>>>>
  I will tackle this one.  The text is probably not clear enough in our
  (UN/CEFACT) spec and we will address this during our face to face in
  early March.

  What the messaging layer must do it provide enforcement via a
  gatekeeping functionality (an explicit tie-in to the Business Agreement
  between the sender and the receiver).  Any ebXML that arrives asserts
  that it exists as "part" of a business relationship.  It does this by
  asserting a unique identifier to an XML representation of that Business
  Agreement called a CPA.  The messaging layer can access an API to verify
  if that CPA ID is valid.

  Furthermore,  since any single business relationship may involve several
  concurrent threads of a business process (ie - procurement), the
  incoming message must specify a Conversation ID, an assertation that it
  is one message belonging to a specific choreography of messages (thread?).

  WSDL + SOAP do not have this functionality explicitly required, however
  that would not stop someone from implementing it by requiring that tie
  in as one of the required parameters. Therefore, WSDL + SOAP can provide
  this.  It is conceivable that someone could implement a WSDL/SOAP WS
  that had a tie in to an ebXML CPA instance.

  This is what was meant by the statement in the architecture document.
  We obviously may need to re-visit this sentence to see if we need to
  clarify it.   Please also keep in mind that the UN/CEFACT architecture
  is not ebXML specifc.  It is not dependant on ebXML components being
  used and actually presumes that WSDL + SOAP may be an underlying
  implementation strategy.  Therefore, we (UN/CEFACT eBusiness
  Architecture Working Group) need to make sure we get this right.

  > It seems a bit like asking IP
  > to understand HTTP.  On the other hand, maybe our textbook notions of
  > protocol layering are not holding up in the Real World, e.g. firewalls
  > arguably *should* understand IP, TCP, HTTP, SOAP, SAML, WS-Security,
etc.
  > and their interrelationships.
  >>>>>>>>>>>
  This was driven out of a set of business requirements collected by over
  2000 contributors around the globe.  The messaging layer does not need
  to understand what the layers up the stack are doing, just be capable of
  enforcing those rules of engagement.  Therefore,  a transport level
  acknowledgement should not to be construed as a business acceptance of
  the message etc etc.

  Duane Nickull
  -
  VP Strategic Relations,
  Technologies Evangelist
  XML Global Technologies
  ****************************
  ebXML software downloads - http://www.xmlglobal.com/prod/
Received on Thursday, 13 February 2003 01:02:45 GMT

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