Administrative interactions between distributed InterChange Server Express components are enabled by the Common Object Request Broker Architecture (CORBA).
Content data transfers--that is, the business data that is being exchanged--can utilize either CORBA, or messaging technology provided by the Java Messaging Service (JMS) using WebSphere MQ queues.
The Common Object Request Broker Architecture (CORBA) defines a set of standards and interfaces for distributed objects on a network. The Object Request Broker (ORB) is a set of libraries and other components that client applications and object servers use to communicate. InterChange Server Express uses the IBM Java ORB product.
The ORB makes InterChange Server Express accessible to its clients, the connector agent, and System Manager. An InterChange Server ExpressExpress instance registers with the ORB's name service, from which a client obtains the information it needs to find and start interacting with the server. The client and server perform object-to-object interactions by means of the ORB's Interface Definition Language ( IDL). At a transport level, they communicate by means of the Internet Inter-ORB Protocol (IIOP). ORB-based communication is typically used for the following purposes:
In the IIOP request/response protocol, communication either succeeds or fails immediately, so both programs must be running for the components to communicate. However, for request/response interactions in an InterChange Server Express implementation, you can use a connector property to set a store-and-forward mode, specifying how a connector controller will respond to a collaboration's request in a situation where the connector agent is unavailable:
Messaging embodies a communication style in which programs asynchronously exchange discrete units of data (messages). Programs that use a messaging transport need not establish connections or wait for messages; each program asynchronously sends and receives messages by interacting with the messaging service. The messaging service provides guaranteed delivery, storing the message if the destination program is unavailable and retrying until it is available.
Java Messaging Service (JMS) is supported as the messaging system.
When JMS is the delivery transport mechanism, data persistence can be provided through the long-lived business processes feature. When this feature is used, a process initiated by a request on a collaboration can be placed in a waiting state with a timeout value, so that the process will be resumed if and when a specified data response is received. Use of this feature requires that the feature be enabled during the creation of the collaboration template.