- From: Heather Kreger <kreger@us.ibm.com>
- Date: Mon, 4 Mar 2002 10:14:23 -0500 (EST)
- To: www-ws-arch-request@w3.org
Boy, you guys don't even take weekends off! Actually, I think that by phrasing it as an 'application programming interface', it implys the lack of requirement for human involvement and the ability to interact with other software components. If we agree this is so, we could simplify the definition to: "A web service is a software application or component identified by a URI that is accessible via internet protocols and supports an application programming interface and binding that is capable of being described by standard formats." I'm not really sure we need "by standard formats" (it begs questions like What's a standard format? Who's standard format?), but I'm willing to live with it. I always try to apply the one breath test to definitions. If you can't recite a definition in one breath then it may be too long and complicated and risks being to hard for anyone to remember accurately. We can recite this one in one breath (if you take a big breath first :-D ). Heather "Krishna Sankar" <ksankar@cisco.com>@w3.org on 03/04/2002 12:35:33 AM Sent by: www-ws-arch-request@w3.org To: <www-ws-arch@w3.org> cc: Subject: RE: Web Service Definition [Was "Some Thoughts ..."] Stephen, That is fine. You are talking about the "services" part (more precisely the distributed services/computing) which was there all along before the "browser" paradigm. I am sure you agree that there is not that much new in the "web services" world except possibly the self describing (still questionable, yet) data "encoding" i.e. XML and the resultant derivatives like SOAP,... OTOH, I do agree that at we need to do is also to say what web services do not require. I liked the way Dan Gunter described it "what seems most notable about web services is what they are not, i.e. unlike CORBA they don't mandate an object model, unlike Java they don't require a programming language or VM, etc. Maybe mentioning what a web service is _not_ required to be, as part of the definition, would help clarify somewhat, and it may also help solidify its relation to the rest of distributed computing." So if we want to rattle out what web services are not, it would be OK - it might be a long list. cheers | -----Original Message----- | From: Vinoski, Stephen [mailto:steve.vinoski@iona.com] | Sent: Sunday, March 03, 2002 7:11 PM | To: Krishna Sankar | Cc: www-ws-arch@w3.org | Subject: RE: Web Service Definition [Was "Some Thoughts ..."] | | | Human interaction is mentioned because traditionally that's what the web | is about. Web Services represents an evolution from a browser-to-web | server model to an application-to-application interaction model -- | that's really what makes them so important. | | --steve | | > -----Original Message----- | > From: Krishna Sankar [mailto:ksankar@cisco.com] | > Sent: Sunday, March 03, 2002 12:49 PM | > To: www-ws-arch@w3.org | > Subject: RE: Web Service Definition [Was "Some Thoughts ..."] | > | > | > 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 Monday, 4 March 2002 16:27:58 UTC