Subject: RE: [ws-caf] [WSRF][Fwd: [OASIS members] Press Release to Announce OASIS
All, > > After spending a great deal of time yesterday with the Globus and IBM > folks behind this spec, my feelings are generally unchanged though I do > sympathise with what they tried to achieve. In the application domains > they're thinking about, resources are really important and so they > figure in their specs. I think I am just concerned about the notion of > resources permeating down the stack where it would class with the simple > services-plus-messages view. Like Jim and after loooong discussions with the WSRF authors, I think I have a better understanding of what WSRF is trying to achieve. The use of WS-Addressing to contextualise interactions with (logical or physical) resources behind a service boundary is not the main issue. However, I believe that the conceptual model that is suggested and is used by some of specifications that are built on top of WSRF may lead to fragile applications. I believe that the model encourages the design of distributed applications around the concept of resources and sharing of those resources. Instead of documents being exchanged, endpoint references (EPRs) are exchanged. I have just seen how the WS-Agreement has been designed. Instead of exchanging agreement documents the entire protocol is based on the exchange of EPRs. Agreements are not agreed for conversations (distributed units of work or activities) but, instead, agreements are used for the creation of resources. Needless to say agreements themselves are resources. It's only the interactions with the newly created resources that fall under the terms of an agreement. This model does not scale and, in fact, they have chosen to model only bilateral agreements. They suggested to me that multi-party agreements are not used in real life!!! (yes, I know!). I told them about how easy it would be to use coordination or transactions to model the negotiation process for an agreement and then use the agreement to as part of a contextualised interactions but that doesn't really fit well with their resource-based model. So, to answer one of Joe's questions... I don't see a problem with identifying a file through a WS-Address + some local-to-the-service information but I see a problem with building scalable applications that extensively utilise network-wide pointers to resource beyond organisation boundaries. WSRF encourages just that. Of course you can choose to not use WSRF in that way but that's its intended use from what I see here in GGF. Best regards, .savas.