--- Steve Jones <[EMAIL PROTECTED]> wrote:

> I love the implication that business aligned is a
> bad thing.

It's not, normally ;-)   And you certainly could
create business-aligned WSDL operations that are
shared within a supply network or an industry, if you
had the will and influence and political savvy.  But
broadly speaking, human organizations disagree on
terms, definitions, and the relative "importance" of
one operation over a nother.  And disagreement hurts
interoperability.    

Here's another take on it...

If you want to interoperate the classic "RPC" way, you
build your operations, and then describe your
interface, and someone bends their worldview into your
worldview when they invoke you.   EAI made this more
economical, and the latest web services tools (WSDL)
make this even more economical, but it's still a
matter of percentage points of productivity

In the "SOA" way, your producers and consumers get
together, bang out a shared contract, and govern /
evolve that contract over time.  That includes data
formats and shared operations.  Costs start to drop
much more significantly, as you reduce the number of
potential transformations.

In the "REST" way, it's like SOA, but more constrained
-- we align the contract on the most general
operations possible -- In HTTP's case,
GET/POST/PUT/DELETE.  If "everyone" can just agree on
one small thing, such side effects, or idempotence,
we've generated a universally interoperable operation,
one with tremendous value.  

Or, as Roy Fielding put it a few years ago, "The Web
creates more business value, every day, than has been
generated by every single example of an RPC-like
interface in the entire history of computers."

> But to the point, there is no business value in PUT,
> its the actual EXECUTION that gives the value.

Actually, and this may come across as bizarre, but
most of the value is not in the execution.  It's in
how these things are arranged in a system
configuration that provides the greatest value.

The whole idea of large scale organization, going back
to Adam Smith in economics,  Peter Drucker in
management, etc. is that the "system" is what's
productive, not the execution of any individual task. 
 

This is the argument for a market-based organization
of an economy vs. a planned economy.  This was also
the insight of the Ford system, and is also the
insight of the Toyota production system, or "lean"
approaches.  While you may be able to derive value out
of the execution of a task at a certain granularity,
the real value to be gleaned from how it is arranged
into an integrated system.

And the whole REST argument is that there are some
styles of systems organization that have more powerful
& desirable properties for large-scale decentralized
computing than others do.

> We become obsessed with technology and
> completely lose track of
> the business value and objectives.

I completely agree with this.  But I also think that
REST v. WSDL is just a symptom of a broader issue, one
that has major business implications, and won't be
solved soon... ;-)

Cheers
Stu

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