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RE: WSA constraints

From: Anne Thomas Manes <anne@manes.net>
Date: Mon, 23 Sep 2002 10:41:09 -0400
To: "Mark Baker" <distobj@acm.org>, <www-ws-arch@w3.org>
Cc: <mark.baker@sympatico.ca>
Message-ID: <ECEDLFLFGIEENIPIEJJPAEGLCHAA.anne@manes.net>

I disagree. I don't think the *architecture* is constrained by the
capabilities of SOAP 1.1 and WSDL 1.1.

I also don't agree with your list of "constraints".

In particular, I doubt think that the architecture is not constrained to
client/server. Most people use Web services within the constraints of the
client/server pattern, but does the architecture constrain it that way?
Doesn't the architecture also support peer-based messaging? The SOAP 1.1
spec talks about senders and receivers. The WSDL 1.1 spec talks about four
different message exchange patterns. I gather that the original authors
never intended to constrain the architecture to client/server.

Certainly the name "service" implies client/server. Almost all SOAP
implementations are based on the client/server model (most use an app server
container model). But there's no reason why you couldn't build a
peer-to-peer communication system based on Web services technology. Do we
want to impose a client/server constraint on the architecture?

(Which raises an issue -- Heather's diagram implies client/server.)

I agree that the Web services architecture relies on / exploits "layering".
Does that constitute a "constraint"? (Constraint implies limitation. The way
Web services uses layering removes limitations.)

I agree with Dave that XML messaging is a constraint. Web services
participants communicate by passing XML messages. If two applications
communicate using anything other than XML messages, then they are not using
the Web services architecture.

Anne

> -----Original Message-----
> From: www-ws-arch-request@w3.org [mailto:www-ws-arch-request@w3.org]On
> Behalf Of Mark Baker
> Sent: Sunday, September 22, 2002 2:00 PM
> To: www-ws-arch@w3.org
> Cc: mark.baker@sympatico.ca
> Subject: WSA constraints
>
>
>
> (acm.org seems to be having mail forwarding troubles, so please CC
> mark.baker@sympatico.ca)
>
> > I get nervous when people say things that imply they want
> > the TAG to be the Court of Appeals for that process.  IMHO that's
> > antithetical
> > to the "consensus on means if not ends" idea that is at the heart of
> > any effective industry consortium.  I see this WG as a place for the Web
> > industry to get together, sort architectural issue out into what we can
> > agree on and
> > what we must agree to disagree on, all with the input from the public at
> > large and the considered advice of the TAG.  There ain't no
> Final Authority
> > here other than what works in the real world.
>
> I'm trying to get past that.  I'd hope that the suggestions I present
> would be judged on their own merits.
>
> With that in mind, I think documenting the constraints implicit in the
> software developed to SOAP 1.1 + WSDL 1.1 is the best way to describe
> the architecture of the system.  So far I've suggested that the existing
> WSA includes these constraints on the relationships between components;
>
> - layered
> - client/server
>
> and DaveO suggested;
>
> - XML messages
>
> I'm suggesting we continue this process, and include the results in the
> architecture document.
>
> Thanks.
>
> MB
> --
> Mark Baker, CTO, Idokorro Mobile (formerly Planetfred)
> Ottawa, Ontario, CANADA.               distobj@acm.org
> http://www.markbaker.ca        http://www.idokorro.com
>
Received on Monday, 23 September 2002 10:40:33 GMT

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