RE: A stratification picture

Frank,

I actually think this work is very interesting and pertinent.  It provides a good way of categorizing and separating the problem spaces. 

But I'd also suggest that for "V1" of the architecture that we try to limit the scope to levels 0 and 1, and plan to return to the semantic questions in a future version.

I had made an earlier proposal to confine the "V1" scope primarily to the relationships among the XML applications, which is somewhat related to my suggestion here -- meaning that we try to nail down more of the "known" or at least relatively known universe before expanding the scope.

I think we know, for example, that we need to establish the relationship among SOAP, WSDL, and UDDI as a kind of first principle (and we have definitely been working on this).  And I think we also know we need to estbablish the relationships among the "first principle" technologies and some of the "higher level" technologies.  But I do not think we are far enough along with this basic work to undertake (at least not at the same time or without serious distraction) the work to establish relationships among the technologies and the semantics of their application.

So my suggestion would be to find a good place for the diagram, and use the diagram (with the accompanying text) to help explain what's in scope for "V1 WS."

Eric

-----Original Message-----
From: Francis McCabe [mailto:fgm@fla.fujitsu.com]
Sent: Wednesday, May 14, 2003 1:52 PM
To: www-ws-arch@w3.org
Subject: A stratification picture


This picture is intended to help clarify some of what I meant about 
stratification.

The white concepts belong to what I was calling level 0 stratification: 
We have a message, and the message has a sender. (There is of course 
much more)

The yellowed box (description) is at level 1. By having an agreed way 
of describing messages we can gain increased interoperability, 
primarily at the syntactic level.

The green boxes are examples of concepts belonging to a level 2 
stratification. REST, application specific and ACTION SOA are all 
alternatives.

The relationship between these concepts is interesting, as it also 
points to automation tools.

1. Having a machine readable description of a message allows tools to 
verify that a message conforms to the description, and may also help 
tools to generate conforming messages.

2. When a description encodes a semantics, that means that valid 
messages (in this case) are also valid entities in the semantics. In 
the case of REST, that would mean that we could state that a particular 
message is a GET message for example.

3. Similarly, when we state that a message satisfies a semantics, we 
state that the message is a valid POST message, or a valid invoice 
request message (in the case of application specific semantics). If it 
is possible to describe the semantics in a machine readable form, then 
we could have tools that automatically verify that a message is a valid 
REST message -- potentially meaning more than syntactic; it could 
include a check for example that a referenced URI denoted a valid 
resource.

Received on Wednesday, 14 May 2003 15:19:15 UTC