IBM is batty over OGSA

From what I can tell, three major themes are coming out of the IBM software group:
1. Model Driven Architecture (a byproduct of purchasing Rational)
2. Web Services (a byproduct of being in bed with Microsoft)
3. OGSA (a byproduct of wanting to beat Microsoft)

The OGSA is an interesting beast and at the heart of it you will find web services:



For more information on OGSA, check out:
http://www-106.ibm.com/developerworks/webservices/library/gr-visual/

One thing I didn't really get was why they have OGSI services laying on top of web services, and their explanation didn't help:

Let's look more closely at the two main logical components of OGSA -- the Web services-plus-OGSI layer, and the OGSA architected services layer. See Figure 2. Why are they separated like this? The GGF OGSA working group believed it was necessary to augment core Web services functionality to address grid services requirements. OGSI extends Web services by introducing interfaces and conventions in two main areas.

First, there's the dynamic and potentially transient nature of services in a grid. In a grid, particular service instances may come and go as work is dispatched, as resources are configured and provisioned, and as system state changes. Therefore, grid services need interfaces to manage their creation, destruction, and life cycle management.

Second, there's state. Grid services can have attributes and data associated with them. This is similar in concept to the traditional structure of objects in object-oriented programming. Objects have behavior and data. Likewise, Web services needed to be extended to support state data associated with grid services.

IMHO, the ws layer should front end all of the service - both of the aforementioned issues seem resolvable. Perhaps the IBM boys will set them straight...