WebSphere Service Integration Bus
The WebSphere Service Integration Bus (SIBus) is the default built-in messaging provider for WebSphere. The messaging provider serves as the back-end message-oriented middleware (MOM) for applications that require messaging services. This separation of application logic and messaging functionality allows for interchangeability between the application layer and the messaging layer. Therefore, an application that uses the WebSphere SIBus can easily switch to MQ, another message provider in WebSphere. Figure below illustrates how the SIBus interacts with other components in the application server.
The SIBus handles many important tasks, including sending and receiving messages, persisting messages, and setting up mediations between sender and receivers. For our single-server environment, we must configure our application server as a member in the SIBus. After a server becomes a member of the SIBus, the SIBus establishes a message engine for the server. Within the messaging engine, you can configure messaging destinations for the server member.
In order for applications within the web container to access the messaging services of the SIBus, you must configure resources within the application server both on the client side and on the server side. On the client side, you must configure a connection factory resource and destination resource to allow for access to the messaging engine within the SIBus member and the destinations hosted within it. This access allows the client to send messages to the SIBus. On the server side, you must configure a set of activation specifications for client MDBs to receive messages from the messaging engine, which allows the server to retrieve the messages from the SIBus.