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

RE: A question for our leaders (was RE: AR023.7.1 (was Re: Dead trou tSide
note: I'm glad you've quoted the dictionary for this one.

An architecture for building a computer will be different from an
architecture for building a software component. If you're coming from the
software world (like me) you may find it hard to talk to someone coming from
the hardware world because sometimes we associate terms like 'architecture'
with connotations that are specific to the context in which we use them.

To have an informed discussion it's helpful if we let go of these
connotations and try to look at the commonality, so resorting to a neutral
dictionary definition of the term is always helpful ;-)

arkin

PS And I would admit to all too often using a term wrongly by applying too
much context to it.

  -----Original Message-----
  From: www-ws-arch-request@w3.org [mailto:www-ws-arch-request@w3.org]On
Behalf Of Burdett, David
  Sent: Monday, February 24, 2003 4:21 PM
  To: Assaf Arkin; Burdett, David; Cutler, Roger (RogerCutler); Champion,
Mike; www-ws-arch@w3.org
  Subject: RE: A question for our leaders (was RE: AR023.7.1 (was Re: Dead t
rou t


  Arkin

  Merriam Webster defines architecture as follows ...

  1 : the art or science of building; specifically : the art or practice of
designing and building structures and especially habitable ones
  2 a : formation or construction as or as if as the result of conscious act
<the architecture of the garden> b : a unifying or coherent form or
structure <the novel lacks architecture>
  3 : architectural product or work
  4 : a method or style of building
  5 : the manner in which the components of a computer or computer system
are organized and integrated

  I think you are assuming definition "1" which is the art/science of how to
do architecture. I don't think we are doing this. I think we are doing
something closer to a "4" or a "5".

  Additionally, if the WSA doesn't do the "architecture for eCommerce" or
the architecture for treating the web as an information resource then who
will, and when do you think it will be complete?

  David
    -----Original Message-----
    From: Assaf Arkin [mailto:arkin@intalio.com]
    Sent: Monday, February 24, 2003 11:09 AM
    To: Burdett, David; Cutler, Roger (RogerCutler); 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 actually think there is one 'architecture' for solving all design
problems, and variety of 'architectures' for solving specific design
problems.

    If you go to architecture school you learn about that one architecture.
It is generic enough to let you build bridges, hospitals and parking lots,
because it is very generic. I think the WSA should devise an architecture
like that.

    On the other hand, if you build a loft for residence as opposed to a
dual-home dwelling there are different constraints you would use. All lofts
are built based on three common paradigm, and loft architects have specific
experience in that domain and are probably not hte people you would contact
to build a bridge or a hospital.

    I don't think we need to overload the WSA with 'an architecture for
e-commerce', but we definitely need some place to design such an
architecture that could use those artifacts that are only interesting for
e-commerce (e.g. SOAP, WS-RM, WS-Security) and also expand on those concepts
that are specific to e-commerce but of no interest to WS in general (e.g.
UBL, DBNs, etc).

    arkin

      -----Original Message-----
      From: Burdett, David [mailto:david.burdett@commerceone.com]
      Sent: Monday, February 24, 2003 10:44 AM
      To: Cutler, Roger (RogerCutler); 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


      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.