IBM WebSphere ESB Interview Questions

1.What is ESB?

A. An enterprise service bus (ESB) is software architecture for middleware that provides fundamental services for more complex architectures. For example, an ESB incorporates the features required to implement a service-oriented architecture (SOA). In a general sense, an ESB can be thought of as a mechanism that manages access to applications and services (especially legacy versions) to present a single, simple, and consistent interface to end-users via Web- or forms-based client-side front ends.

2. What is the functionality of Fan-in and Fan-out?

A. Fan-out:We can use the Fan Out primitive to fire the output terminal once (with the  input message) or to fire the output terminal multiple times. You    can use Fan Out in isolation or as part of a Fan Out and Fan In combination.

Fan-In: Fan In is always partnered with a Fan Out in the same flow and acts   as a decision point for when to continue flow execution. It receives a number   of messages until a decision point is reached, at which point the last message  to be received is propagated to the output terminal. The Fan In primitive may   only be used in combination with Fan Out. 

3. What are all the configurations required for JDBC Adapter implementation?

A. Data Source need to be created and need to configure with DB. If we have security, then need to created security authentication.

4. Different between SDO and SMO?

A. SDO: Service Data Object is the representation of the variable or Object.

SMO: The SMO model is a pattern for using SDO Data Objects to represent messages

5. Difference between Stop and fail?

A. Stop: Stops a particular path in the flow, without generating an exception.

Fail: Generates a failure in the flow.

6. How can you change the runtime changes using mediation primitive?

A. We have future called Promotable properties in ESB. We can configure this future while development. Then we can make it changed at runtime without restarting  the server it can be published.