RE: A question for our leaders (was RE: AR023.7.1 (was Re: Dead t rou t

Let's think about architectures for creating buildings. Can a reasonable
person actually maintain that there is only *one* architecture that is
correct for solving any design problem. I don't think so. If that was the
case then all buildings would look exactly the same.

I also think it is fairly obvious, that if you have "architectural design
briefs" with different needs and requirements then you need different
architectures. This is why a hospital looks different from a factory and
from a home. They all have different needs.

Now to the WSA. I think that we have two sets of "design briefs" we need to
satsify:
1. For the web as a huge information resource, and
2. As a low cost transport of documents for eCommerce

Now a lot of the stuff can be common between the two. A door or a window in
an hospital, factory or home, can be the same. Similarly there are many
similarities between a message sent to request a representation of a
resource and a message sent to a business partner containing a business
document. But they are not the SAME!

So let's make this separation explicit and move forward. Anyone disagree?

David

-----Original Message-----
From: Cutler, Roger (RogerCutler) [mailto:RogerCutler@chevrontexaco.com]
Sent: Monday, February 24, 2003 9:38 AM
To: Burdett, David; Assaf Arkin; Champion, Mike; www-ws-arch@w3.org
Subject: RE: A question for our leaders (was RE: AR023.7.1 (was Re: Dead
trou t


I agree.

However, as illustrated by the "visibility" permathread, I think that we
are going to have a heck of a time reaching consensus on the guidelines
-- unless we are willing to accept a "consensus" that includes a
strongly dissenting opinion.  Personally I would like to work toward
this objective and stop running over the same material that has no
resolution over and over and over and ...

-----Original Message-----
From: Burdett, David [mailto:david.burdett@commerceone.com] 
Sent: Monday, February 24, 2003 10:58 AM
To: Assaf Arkin; Burdett, David; Champion, Mike; www-ws-arch@w3.org
Subject: RE: A question for our leaders (was RE: AR023.7.1 (was Re: Dead
trou t



Assaf

I agree, but can we, as a group, also agree that there are two different
use cases that have different requirements and therefore require
differing solutions. Really, the analysis we need to do, is identify
what is common and what is different and explicitly propose an
"architecture" for solving both. Would that make sense.

I agree that we should have phrasing that allows both, but "leaving it
to the implementation to decide which works best" is two weak.
Alternatively, I suggest that: 1. We define two architectural
approaches: one which follows the REST style for encoding the operation;
and the other where the operation information is stored in the body 2.
Provide guidelines/criteria which helps an implementation decide which
to use

David

-----Original Message-----
From: Assaf Arkin [mailto:arkin@intalio.com]
Sent: Sunday, February 23, 2003 4:21 PM
To: Burdett, David; Champion, Mike; www-ws-arch@w3.org
Subject: RE: A question for our leaders (was RE: AR023.7.1 (was Re: Dead
trou t




> -----Original Message-----
> From: www-ws-arch-request@w3.org [mailto:www-ws-arch-request@w3.org]On
> Behalf Of Burdett, David
> Sent: Sunday, February 23, 2003 3:56 PM
> To: Champion, Mike; www-ws-arch@w3.org
> Subject: RE: A question for our leaders (was RE: AR023.7.1 (was Re: 
> Dead trou t
>
>
>
> Mike
>
> Thanks for the feedback. I suppose that the motivation for my asking 
> this question, is that there are various requirements for using web 
> services for business that, although they may seem minor, have some 
> major architectural implications. Here are three examples:
>
> 1. Semantic free URIs
> In an earlier email, I suggested that if you want to keep the content 
> of a message sent to a web service confidential, then you should not 
> put ANY sensitive information such as the operation to be carried out 
> on the message in the URI

I think there are valid use cases where it is easier to include that
information in the URI, e.g. a catalog service. If there's no
requirement for security, auditing, etc then why complicate it. An HTTP
GET would be simpler to implement/use in this case.

However, enforcing that model goes against business requirements, and
the points you make are very valid. I would suggest a phrasing that
allows both uses but leaves it to the implementation to decide which
works best, and ideally making that decision in the protocol bindings.

Maybe something like:

There is no requirement that all information pretaining to the operation
be captured in the URL, for example, to allow such information to be
contained in the message body and encrypted.

arkin

>
> 2. Use of non-HTTP Protocols
> I really think that SMEs (Small to Medium Enterprises) will want to 
> provide a Web Service capability using email protocols rather than 
> HTTP. The EDI use
> case at in the WSA Usage Scenarios document is a good example of this.
> Also, within an enterprise, other non-HTTP protocols could be used
such as
> MQ Series. This is suggested in the Transport section of the Web
Services
> Architecture Document.
>
> 3. Preservation of Message Integrity
> Many messages sent to web services providing a business function will 
> be digitally signed, probably with XML Dsig, as they provide a 
> *persistent* record of the origin and authenticity of the message that

> lasts after the transport of the message is complete. For example, you

> could store the message in a database or file system without losing 
> any integrity information.
>
> The conclusion I draw from these example requirements is that you have

> to put all the semantic information required to process a message 
> actually
> *inside* the message. If information is contained at the
> transport level as
> Mark and others have suggested, then it MUST be a copy.
>
> Thoughts?
>
> David
>
>
>
> -----Original Message-----
> From: Champion, Mike [mailto:Mike.Champion@softwareag-usa.com]
> Sent: Thursday, February 20, 2003 5:56 PM
> To: www-ws-arch@w3.org
> Subject: RE: A question for our leaders (was RE: AR023.7.1 (was Re: 
> Dead trou t
>
>
>
> >
> >
> > -----Original Message-----
> > From: Burdett, David [mailto:david.burdett@commerceone.com]
> > Sent: Thursday, February 20, 2003 2:02 PM
> > To: Dave Hollander (E-mail); Mike Champion (E-mail)
> > Cc: www-ws-arch@w3.org; 'Cutler, Roger (RogerCutler)'; Mark Baker
> >
> > A question for our leaders ...
> >
> > To what extent is the requirement to develop a Web Services 
> > Architecture that supports the needs of business/ecommerce a formal 
> > objective of this activity?
>
> The answer is "yes, of course."  Oddly enough, the Requirements don't 
> say this as explicitly as I remembered, maybe because we "just knew" 
> that the objective is to support the needs of business.
>
> What the Requirements doc does say is: "Of course, it is also 
> important to recognize that an important motivation for the product of

> this Working Group is to support the needs of enterprises that use Web

> services for the purpose
> of engaging in e-business."
>
> This is clearly not just an academic exercise; an intellectually pure 
> architecture that doesn't actually have real-world implementations or 
> reflect practical business knowledge would not meet the requirements 
> of this activity.
>
> Of course, one would be forgiven for not getting that impression from 
> this mailing list :-)  But that's the price we pay (and benefit we 
> get) from doing the technical work in public.