- 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
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 UTC