A service assembly is a single ZIP archive containing a standard JBI descriptor (jbi.xml) and zero or more service units. You can think of a service assembly as an archive of archives that package together the individual service units and configurations into a single deployable entity.
Service Assemblies are typically created in a development tools environment, such as that provided by NetBeans 5.5 Enterprise Pack. Once an assembly is ready for use, it is deployed to the JBI environment. The JBI environment automatically distributes the artifacts to the appropriate JBI components that use them. You can deploy Service Assemblies using the Administration Console, the Command Line Interface, the tools available with NetBeans 5.5 Enterprise Pack, or the Ant tasks provided with Open ESB and executed using the Application Server 9.1 Beta asant utility.