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RE: eCommerce Choreography Use Case

From: Heather Kreger <kreger@us.ibm.com>
Date: Fri, 25 Oct 2002 09:43:49 -0400
To: "David Orchard" <dorchard@bea.com>
Cc: www-ws-arch@w3.org
Message-ID: <OFC51FC451.2E26A590-ON87256C5D.004A3AAE@us.ibm.com>





So if we wanted to have a people-less travel scenario then perhaps we could
use this idea:

FutureLeisure in New York has asked me to write a program that books new
popular itineraries six months in advance as
flights and cruise schedules are released.

The popular itineraries are well known:
1. Alaskan Cruise special
2. Paris in Spring special
3. Carribian Cruise special
4. Ski package special
5. Antiquities Tour (Visits cool historical places: Rome, Athens, Cairo)

All itineraries depart from NY LaGuardia on a Friday and return the
following Sunday (10 days).

This program must run once a week in order to get best advance purchase
prices, low cost fares for air travel and cruises.
This program books 10 of the 5 itineraries every week
This program seaches for the best air fare, hotel rate, and cruise rates
from a set of brand name vendors (American Airlines, Delta, United,
Marriott, Sheraton, Holiday Inn, Princess Cruise lines, Carnival Cruise
lines, etc.)

The travel agency sells these itineraries to customers much closer to the
date of travel at a lower price than can be booked at that time, but still
much more than the booked price.



Heather Kreger
Web Services Lead Architect
STSM, SWG Emerging Technology
kreger@us.ibm.com
919-543-3211 (t/l 441)  cell:919-496-9572


"David Orchard" <dorchard@bea.com>@w3.org on 10/24/2002 07:07:24 PM

Sent by:    www-ws-arch-request@w3.org


To:    "'Burdett, David'" <david.burdett@commerceone.com>, "'WS
       Architecture \(E-mail\)'" <www-ws-arch@w3.org>
cc:
Subject:    RE: eCommerce Choreography Use Case




David,

Excellent observations, muchos thanks.

What  if we made it such that a machine was interacting with the travel
reservation  service instead of a human?  This is a great example of
converting a web  site into a web service and expanding markets
</marketing>

And  what if the interaction between the travel service and an airline was
discovered  earlier?

How  about making the airline booking and/or hotel confirmation arrive from
the  airline asynchronously?  Then they could arrive in various  orders.

Would  these changes/additions then make it sufficient to talk about
choreography?

Cheers,
Dave
-----Original Message-----
From: Burdett, David  [mailto:david.burdett@commerceone.com]
Sent: Thursday, October 24,  2002 2:33 PM
To: 'David Orchard'; 'WS Architecture  (E-mail)'
Subject: RE: eCommerce Choreography Use  Case



David

Firstly, I'm suggesting the eCommerce is an additional use  case and not a
replacement for the travel reservation use case as it  illustrates a number
of additional ways in which web services could be used.  These are
described below:

PEER-TO-PEER MULTI-PARTY COMMUNICATION
In the travel reservation service, the user always interacts via the
travel service from a form. This very much like a web client-server
relationship and means that the user does not need to know anything about
how  the travel service interacts with the airlines and the payment
service. In the  eCommerce example, each participant (buyer, seller,
shipper) is an equal peer  of each other and has to know the complete
process so that they can correctly  interact.

EXTERNALLY DEFINED CHOREOGRAPHY
In the  travel reservation service, there is a requirement for the travel
service to  discover how to interact with the airlines and with the payment
service. It  then handles each interaction dynamically depending on
ontology definitions  that allow it to do the mapping of the content of the
messages. In the  eCommerce example, the choreography (i.e. sequence of
exchanging messages) has  been defined by a separate third party that all
the three participants  recognize they must conform to and which they HAVE
to build into their  implementations.

CHOREOGRAPHY REUSE
The eCommerce  example is simplified as it does not include the generation
of errors nor the  compensating message flows and processes which must be
excecuted to handle  them. Therefore a complete choreography would actually
contain many more  steps. Because of this complexity there is a lot of
benefit in reusing the  same standardized choreography with many buyers,
sellers and shippers in order  to reduce implementation costs. EDI has done
this in the past by publishing  implementation guides that describe the
inter-party choreographies as text.  Implementations that use languages
such as BPEL or WSCI will need to be  constrained so that they can both
recognize which choreography they are  following and adapt their behavior
accordingly.

THE CHOREOGRAPHY IS INDEPENDENT OF THE MESSAGE CONTENT
The content of each message varies depending on the context  in which it is
used, for example if the choreography is being used nationally,  then no
customs documents are required. At a lower level the content of  individual
documents can change for example an order placed in the chemical  industry
could have additional chemical hazard information on it. This means  that
the individual schemas will be different. However, the actual sequence of
messages and their basic meaning does not change. So the eCommerce example
describes a need for defining a choreography that is independent of the
detail  of the content of each message. This could also have an impact on
service  definition, as if, for example, there is a slightly different
definition for  each order docment depending on industry, it could mean
that each participant  (buyer, seller, shipper) would have to define
separate WSDL definitions.  Thoughts?

PARALLEL PROCESSING
The travel  reservation service follows a linear process. The main
parallelism is (I  think) in searching for flights and hotels, for example.
In the eCommerce  example, activities can occur in different time orders
(e.g. sending the  booking confirmation and sending the order response) as
they are generated by  different organizations.

EDI RELATED
This process flow is  modelled closely on actual EDI process flows which
will be one of the main  uses for Web Services. Therefore including a
fairly complex realistic EDI  example is a good idea.

I'd appreciate your thoughts David.

Regards

David

-----Original Message-----
From: David  Orchard [mailto:dorchard@bea.com]
Sent: Thursday, October 24, 2002 10:46 AM
To: 'Burdett, David'; 'WS Architecture (E-mail)'
Subject: RE: eCommerce Choreography Use Case

David,

This looks like an interesting use case.  But I don't  understand the
motivation for it.  How does the  travel reservation service not provide
for
requirements determination?

Cheers,
Dave

> -----Original Message-----
>  From: www-ws-arch-request@w3.org [mailto:www-ws-arch-request@w3.org]On
> Behalf Of Burdett, David
>  Sent: Wednesday, October 23, 2002 6:28 PM
> To: WS  Architecture (E-mail)
> Subject: eCommerce  Choreography Use Case
>
>
> Folks
>
> I promised to draft a set of  requirements for choreography
> definitions.  The
> first step is to prepare a use case and, as  the requirements
> are taking me
> longer than I would have hoped, I thought you might like to
> see just the use
> case  first.
>
> The use case  describes an international eCommerce transaction
>  involving a
> Korean electronics supplier, a US  manufacturer and an
> air-freight company.
> It basically covers the ordering and delivery of goods  using
> a SOAP based
>  exchange of XML documents.
>
> Details are in the attached PDF file.
>
> Comments are welcome.
>
> Regards
>
> David
>  <<eCommerce Use Case.pdf>>
>
> Director, Product Management, Web  Services
> Commerce One
> 4440 Rosewood Drive, Pleasanton, CA 94588, USA
> Tel/VMail: +1 (925) 520 4422; Cell: +1 (925) 216 7704
> mailto:david.burdett@commerceone.com;  Web: http://www.commerceone.com
>
>
Received on Friday, 25 October 2002 09:45:50 GMT

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