In this use pattern WebSphere Application Server is used solely as a notification broker to enable producing and consuming WS-Notification applications to communicate with each other. The applications are unaware that the NotificationBroker service is implemented by WebSphere Application Server.
The following diagram illustrates the variety of clients that are able to connect to the notification broker provided by WebSphere Application Server. Any Web service client that implements or invokes the WS-Notification message exchanges can connect. This includes the various types of Web service clients that are supported directly by WebSphere Application Server (such as JAX-RPC, JSR172, JSR101) and other Web service clients that are capable of using JAX-RPC patterns (for example .NET).
In this use pattern it is possible that none of the clients of the notification broker are written or hosted in a WebSphere Application Server environment, as shown in the following diagram. Note that the notification broker itself cannot determine the environment from which the clients connect because the only interaction is through the standard Web service exchanges defined by WS-Notification.
Similarly, WS-Notification applications written or hosted in a WebSphere Application Server environment (such as JAX-RPC from AppClient, JSR172, JSR101) can connect to non-IBM NotificationBrokers (or NotificationProducers) without any changes to the application code.