Two Sides of the SOAP Coin: Is something missing?

Jon Udell writes about the front-end and Phillip Windley writes about the back-end of web services.

Adam Bosworth also writes about the front end.

There is a client/server feel to this new web services architecture. I don't believe that is anyone's intention, just my perception, because of what's not being described.

Is something missing? I have not quite put my finger on what that is. What is the "middle tier" of a web services architecture?

Here are some thoughts on a component architecture, where components are pieced together in many-many-many relationships for some solution...

• Front - not a browser but browsing/transacting purpose-based component(s), e.g. outline, calendar, form.
• Middle - application-specific aggregating component(s), e.g. work flows (state machines), sorting, searching, tallying.
• Back - OLTP and OLAP data service(s), e.g. the transaction engines for and historical sources of domain knowledge.

The other pieces that are still missing for me are even more central... the priority use-cases and funded evolutionary paths that would drive these visions.