1. DEBA component can establish peer-to-peer, one-to-many, or many-to-many relationships with one another.

2. In this article, we've explained the DEBA framework and how you can use it to implement a variety of flexible distributed application architectures using web services.

3. DEBA is characterized by distributed active components waiting for events.

4. The DEBA architecture ties in very nicely with Grid architectures (see Resources) in that each component can join and leave the grid at will.

5. Thus, DEBA provides a truly dynamic workflow model that is highly decoupled and does not need to be described in advance.

6. The capabilities of the DEBA event model are quite different from those that the limited WSDL Notification operation can provide.

7. The DEBA framework is an implementation of this unique capability.

8. DEBA is able to support variations in the web services implementations and various types of precall checking by externalizing validation.

9. DEBA is unique because it allows the inherently synchronous web services model to provide the foundation for such an entirely asynchronous architecture.

10. Systems built on DEBA can be thought of as always moving towards equilibrium, with participants joining and leaving at will[/deba.html], based on application logic.

11. Table 1 shows the correspondence between the Observer pattern, the standard web services model, and the Observer pattern's implementation in the DEBA framework classes.

12. From Listing 5, you can see that, in order to write an observable that uses the DEBA framework, you have barely anything to do about the underlying SOAP infrastructure.

13. Follow the links in Resources below to download the DEBA framework code and the sample code that accompanies this article.

14. Just as distributed systems are moving towards self-management, components in DEBA are as well.

15. A workflow model central node controls the nodes participating in a distributed state machine and two router models; the entire system is implemented with DEBA.

16. The interaction between the target objects and the visitor can be implemented using DEBA.

17. We've provided a default validation callout mechanism in the DEBA framework to limit exceptions caused by the lack of availability of the observable or observer.

18. There is a great deal of flexibility in the DEBA framework to handle exceptions.