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RE: Web Service Definition [Was "Some Thoughts ..."]

From: Krishna Sankar <ksankar@cisco.com>
Date: Sun, 3 Mar 2002 09:48:55 -0800
To: <www-ws-arch@w3.org>
Message-ID: <NABBJDOPDKGCDCNBNEDOGEKOHCAA.ksankar@cisco.com>
steve,

	Good point - I did miss that. I did read it as denying human interactions,
my mistake.

	My amendment still stands - why mention human interaction at all.

	One, as a service, would implement a capability (either by proxing or
aggregating or by directly performing stuff), define and describe it and
wait ... It really doesn't care who on the other end sends a message (of
course, the message would be based on IP), but when it receives a message,
do some processing and would send back a result or do appropriate stuff in
case of other interaction patterns.

	As a side note, the implicit assumption is that, by defining and describing
the interfaces (and bindings) in a standard way, we are achieving discovery.

cheers

 | -----Original Message-----
 | From: Vinoski, Stephen [mailto:steve.vinoski@iona.com]
 | Sent: Sunday, March 03, 2002 4:14 AM
 | To: Krishna Sankar
 | Cc: www-ws-arch@w3.org
 | Subject: RE: Web Service Definition [Was "Some Thoughts ..."]
 |
 |
 | Note that the definition does not deny direct human involvement. It
 | states only that direct human involvement is not required, which is not
 | the same as saying that it's not allowed.
 |
 | --steve
 |
 | > -----Original Message-----
 | > From: Krishna Sankar [mailto:ksankar@cisco.com]
 | > Sent: Sunday, March 03, 2002 12:08 AM
 | > To: www-ws-arch@w3.org
 | > Subject: RE: Web Service Definition [Was "Some Thoughts ..."]
 | >
 | >
 | > Hi,
 | >
 | > 	Two amendments :
 | >
 | > 	1.	What does the "through an application
 | > programming interface capable of
 | > being described," buy us ? Why not just "capable of being described by
 | > standard formats" ?
 | >
 | > 	2.	Why specifically deny direct human involvement
 | > ? Do we care who (or
 | > what) interacts so long as the interactions are
 | > internet-based protocols ?
 | >
 | > 	IMHO,
 | > 	 "A web service is a software application or component
 | > identified by a URI,
 | > whose interfaces and binding are capable of being described
 | > by standard
 | > formats and supports direct interactions with other software
 | > applications or
 | > components via internet-based protocols".
 | >
 | > 	As Heather says, OK, everyone can open fire now. :-)
 | >
 | > cheers & have a nice weekend
 | >
 | >  | -----Original Message-----
 | >  | From: www-ws-arch-request@w3.org
 | > [mailto:www-ws-arch-request@w3.org]On
 | >  | Behalf Of Vinoski, Stephen
 | >  | Sent: Friday, March 01, 2002 5:08 PM
 | >  | To: James M Snell
 | >  | Cc: www-ws-arch@w3.org
 | >  | Subject: RE: Web Service Definition [Was "Some Thoughts ..."]
 | >  |
 | >  |
 | >  | OK, James, if we take your inputs along with those of
 | > Heather, Mark, and
 | >  | others, and apply them to my original strawman definition including
 | >  | Mark's amendment, we get:
 | >  |
 | >  | "A web service is a software application or component
 | > identified by a
 | >  | URI that, through an application programming interface
 | > capable of being
 | >  | described, supports direct interactions with other
 | > software applications
 | >  | or components via internet-based protocols, where said
 | > interactions do
 | >  | not require direct human involvement."
 | >  |
 | >  | Are we there? :-)
 | >  |
 | >  | --steve
 | >  |
 | >  |
 | >  | > -----Original Message-----
 | >  | > From: James M Snell [mailto:jasnell@us.ibm.com]
 | >  | > Sent: Friday, March 01, 2002 6:21 PM
 | >  | > To: Vinoski, Stephen
 | >  | > Cc: www-ws-arch@w3.org
 | >  | > Subject: RE: Web Service Definition [Was "Some Thoughts ..."]
 | >  | >
 | >  | >
 | >  | > Stephen,
 | >  | >
 | >  | > We actually are on the same page here.  We both seem to agree
 | >  | > that yes,
 | >  | > Web services can be described and discovered, but we disagree
 | >  | > whether or
 | >  | > not those properties need to be called out explicitly in the
 | >  | > definition.
 | >  | > You seem to be saying no, I'm saying yes they do.  The reason
 | >  | > is the same
 | >  | > as why we explicitly define Web resources as having unique URI
 | >  | > identifiers.  Of course Web resources have identifiers,
 | >  | > they're objects
 | >  | > and all objects have identifiers -- of what use is it to
 | >  | > explicitly call
 | >  | > out that point?  The answer is that by stating the fact,
 | > we lay the
 | >  | > groundwork for standardizing how those identifiers are created,
 | >  | > represented, communicated, etc.  We're basically stating that Web
 | >  | > resources need to have a standardized method of
 | >  | > identification.  For Web
 | >  | > Services, explicitly calling out description and discovery as
 | >  | > properties
 | >  | > of a Web service indicate that there needs to be standardized
 | >  | > mechanisms
 | >  | > for description and discovery -- regardless of whether or not
 | >  | > every Web
 | >  | > service actually implements those standards.  Because a Web
 | >  | > Service can be
 | >  | > described and discovered, the overall Web Services
 | >  | > Architecture needs to
 | >  | > take into account standardized mechanisms for description and
 | >  | > discovery.
 | >  | > I'm not saying we have to create such standards here, just
 | >  | > acknowledge
 | >  | > their existence and role.  Make sense?
 | >  | >
 | >  | > - James M Snell/Fresno/IBM
 | >  | >     Web services architecture and strategy
 | >  | >     Internet Emerging Technologies, IBM
 | >  | >     544.9035 TIE line
 | >  | >     559.587.1233 Office
 | >  | >     919.486.0077 Voice Mail
 | >  | >     jasnell@us.ibm.com
 | >  | >  Programming Web Services With SOAP, O'reilly & Associates, ISBN
 | >  | > 0596000952
 | >  | >
 | >  | > ==
 | >  | > Have I not commanded you?  Be strong and courageous.  Do not
 | >  | > be terrified,
 | >  | >
 | >  | > do not be discouraged, for the Lord your God will be with you
 | >  | > wherever you
 | >  | > go.
 | >  | > - Joshua 1:9
 | >  | >
 | >  | > To:     James M Snell/Fresno/IBM@IBMUS
 | >  | > cc:
 | >  | > Subject:        RE: Web Service Definition [Was "Some
 | > Thoughts ..."]
 | >  | >
 | >  | >
 | >  | >
 | >  | > Given that you won't be able to prove it, let's look at it in a
 | >  | > practical manner. Everything in the universe is both
 | > describable and
 | >  | > discoverable. Therefore, speaking about D&D generally
 | > does not add any
 | >  | > clarity to the definition. On the other hand, if you're speaking
 | >  | > specifically about discovery services like UDDI and
 | >  | > description services
 | >  | > like WSDL, then that too is wrong, as I know of several
 | > web services
 | >  | > already in production that use neither WSDL nor anything
 | > like UDDI.
 | >  | >
 | >  | > --steve
 | >  | >
 | >  | > > -----Original Message-----
 | >  | > > From: James M Snell [mailto:jasnell@us.ibm.com]
 | >  | > > Sent: Friday, March 01, 2002 3:57 PM
 | >  | > > To: Vinoski, Stephen
 | >  | > > Subject: RE: Web Service Definition [Was "Some Thoughts ..."]
 | >  | > >
 | >  | > >
 | >  | > > 100% of all Web resources, including Web Services CAN be
 | >  | > > described and
 | >  | > > discovered.  The differentiating factor is HOW.  Every Web
 | >  | > > service CAN be
 | >  | > > discovered regardless of whether or not the Web
 | > service explicitly
 | >  | > > supports a specific discovery mechanism.  Every Web
 | > service CAN be
 | >  | > > decribed regardless of whether or not the Web service
 | >  | > > explicity supports a
 | >  | > > specific description mechanism.  You are right in that
 | >  | > decription and
 | >  | > > discovery alone do not distinguish Web services from other
 | >  | > > types of web
 | >  | > > resources, but that does not mean that the properties of
 | >  | > > discoverability
 | >  | > > and description are not part of the formal definition of a
 | >  | > > Web service.
 | >  | > >
 | >  | > > - James M Snell/Fresno/IBM
 | >  | > >     Web services architecture and strategy
 | >  | > >     Internet Emerging Technologies, IBM
 | >  | > >     544.9035 TIE line
 | >  | > >     559.587.1233 Office
 | >  | > >     919.486.0077 Voice Mail
 | >  | > >     jasnell@us.ibm.com
 | >  | > >  Programming Web Services With SOAP, O'reilly &
 | > Associates, ISBN
 | >  | > > 0596000952
 | >  | > >
 | >  | > > ==
 | >  | > > Have I not commanded you?  Be strong and courageous.  Do not
 | >  | > > be terrified,
 | >  | > >
 | >  | > > do not be discouraged, for the Lord your God will be with you
 | >  | > > wherever you
 | >  | > > go.
 | >  | > > - Joshua 1:9
 | >  | > >
 | >  | > > To:     James M Snell/Fresno/IBM@IBMUS, "Joseph Hui"
 | >  | > > <jhui@digisle.net>
 | >  | > > cc:     <www-ws-arch@w3.org>
 | >  | > > Subject:        RE: Web Service Definition [Was "Some
 | > Thoughts ..."]
 | >  | > >
 | >  | > >
 | >  | > >
 | >  | > > > -----Original Message-----
 | >  | > > > From: James M Snell [mailto:jasnell@us.ibm.com]
 | >  | > > > Sent: Friday, March 01, 2002 1:21 PM
 | >  | > > > To: Joseph Hui
 | >  | > > > Cc: www-ws-arch@w3.org
 | >  | > > > Subject: RE: Web Service Definition [Was "Some Thoughts ..."]
 | >  | > > >
 | >  | > > >
 | >  | > > > A Web Service must be defined as having the properties that
 | >  | > > it can be
 | >  | > > > decribed and discovered.  Both the Web service and it's
 | >  | > > > description must
 | >  | > > > be discoverable.
 | >  | > >
 | >  | > > No, and no. This thread of email already contain multiple
 | >  | > explanations
 | >  | > > of why.
 | >  | > >
 | >  | > > > Definition ==> A Web service can be described and discovered.
 | >  | > >
 | >  | > > As I've already explained using real-world examples, neither
 | >  | > > of these is
 | >  | > > necessarily true (other than the discovery via URI that Mark
 | >  | > > mentioned).
 | >  | > >
 | >  | > > Neither discovery (as in UDDI-like services) nor description
 | >  | > > distinguish
 | >  | > > Web Services from prior art, nor are they found in 100% of
 | >  | > > existing Web
 | >  | > > Services systems. They are therefore not needed to define Web
 | >  | > > Services.
 | >  | > >
 | >  | > > --steve
 | >  | > >
 | >  | > > >
 | >  | > > > - James M Snell/Fresno/IBM
 | >  | > > >     Web services architecture and strategy
 | >  | > > >     Internet Emerging Technologies, IBM
 | >  | > > >     544.9035 TIE line
 | >  | > > >     559.587.1233 Office
 | >  | > > >     919.486.0077 Voice Mail
 | >  | > > >     jasnell@us.ibm.com
 | >  | > > >  Programming Web Services With SOAP, O'reilly &
 | > Associates, ISBN
 | >  | > > > 0596000952
 | >  | > > >
 | >  | > > > ==
 | >  | > > > Have I not commanded you?  Be strong and courageous.  Do not
 | >  | > > > be terrified,
 | >  | > > >
 | >  | > > > do not be discouraged, for the Lord your God will be with you
 | >  | > > > wherever you
 | >  | > > > go.
 | >  | > > > - Joshua 1:9
 | >  | > > >
 | >  | > > > Sent by:        www-ws-arch-request@w3.org
 | >  | > > > To:     <www-ws-arch@w3.org>
 | >  | > > > cc:
 | >  | > > > Subject:        RE: Web Service Definition [Was "Some
 | >  | > Thoughts ..."]
 | >  | > > >
 | >  | > > >
 | >  | > > >
 | >  | > > > By now IMHO we the WG have made the progress that
 | > D&D ought to be
 | >  | > > > in the def.  (Have we not?  I don't want to be
 | > presumptuous here.)
 | >  | > > > So the issue to be settled is whether D&D is already
 | > accounted for
 | >  | > > > in URI.
 | >  | > > >
 | >  | > > > In my view URI is for addressability.  A globally
 | > unique ID offers
 | >  | > > > no intrinsic value to a resource's discovery.  E.g.
 | > there's no way
 | >  | > > > johny, seeking to buy books, can discover a book seller by
 | >  | > > > inferring from a URI like http://www.amazon.com.
 | >  | > > > Mark's made some good points; yet I find the
 | >  | > > > "D&D-accounted-for-in-URI"
 | >  | > > > argument too tenuous.  Withi the web context, D&D is
 | > an integral
 | >  | > > > (as Sandeep put it) part of WS.  It's not a property
 | > that can be
 | >  | > > > assumed by default, thus calling it out is warranted.
 | >  | > > >
 | >  | > > > Cheers,
 | >  | > > >
 | >  | > > > Joe Hui
 | >  | > > > Exodus, a Cable & Wireless service
 | >  | > > > =========================================
 | >  | > > >
 | >  | > > > > -----Original Message-----
 | >  | > > > > From: Mark Baker [mailto:distobj@acm.org]
 | >  | > > > > Sent: Friday, March 01, 2002 6:53 AM
 | >  | > > > > To: Sandeep Kumar
 | >  | > > > > Cc: Vinoski Stephen; Joseph Hui; www-ws-arch@w3.org
 | >  | > > > > Subject: Re: Web Service Definition [Was "Some
 | > Thoughts ..."]
 | >  | > > > >
 | >  | > > > >
 | >  | > > > > Sandeep,
 | >  | > > > >
 | >  | > > > > > If D&D are not an integral part of a Web Service
 | > defintion,
 | >  | > > > >
 | >  | > > > > I was claiming that discoverability *is* an
 | > integral part of the
 | >  | > > > > definition.  It's just already accounted for by defining
 | >  | > > that a Web
 | >  | > > > > service be URI identifiable.
 | >  | > > > >
 | >  | > > > > I know this is a bit different than some Web service work
 | >  | > > > people have
 | >  | > > > > already done, but this is (IMO) one of those times
 | > where our
 | >  | > > > > mandate to
 | >  | > > > > be integrated with Web architecture effects our work.
 | >  | > > > >
 | >  | > > > > > pl help me define
 | >  | > > > > > how would you define a Web (or a Network) of Web
 | > Services,
 | >  | > > > > the participants.
 | >  | > > > > >
 | >  | > > > > > At a high-level, they must at least have the same
 | >  | > > > > characteristics. If not,
 | >  | > > > > > it would be much harder to reason about them
 | >  | > > > semantically, deal with
 | >  | > > > > > managing & monitoring them.
 | >  | > > > >
 | >  | > > > > Sorry, I'm unclear what you're asking.
 | >  | > > > >
 | >  | > > > > MB
 | >  | > > > > --
 | >  | > > > > Mark Baker, Chief Science Officer, Planetfred, Inc.
 | >  | > > > > Ottawa, Ontario, CANADA.      mbaker@planetfred.com
 | >  | > > > > http://www.markbaker.ca   http://www.planetfred.com
 | >  | > > > >
 | >  | > > >
 | >  | > > >
 | >  | > > >
 | >  | > > >
 | >  | > >
 | >  | > >
 | >  | > >
 | >  | >
 | >  | >
 | >  | >
 | >  |
 | >  |
 | >
 | >
 |
Received on Sunday, 3 March 2002 12:49:33 GMT

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