Runtime Behavior of a SOA Composite Application

Figure 1-2 shows the operability of a SOA composite application using SCA technology. In this example, an external application (a .NET payment calculator) initiates contact with the SOA composite application.

For more information about descriptions of the tasks that services, references, service components, and wires perform in an application, see Service Component Architecture within SOA Composite Applications.

Figure 1-2 Runtime Behavior of SOA Composite Application

Description of "Figure 1-2 Runtime Behavior of SOA Composite Application"

The .NET payment calculator is an external application that sends a SOAP message to the SOA application to initiate contact. The Service Infrastructure picks up the SOAP message from the binding component and determines the intended component target. The BPEL process service engine receives the message from the Service Infrastructure for processing by the BPEL Loan Process application and posts the message back to the Service Infrastructure after completing the processing.

Table 1-2 describes the operability of the SOA composite application shown in Figure 1-2.

Table 1-2 Introduction to a SOA Composite Application Using SCA Technologies

Part	Description	Example of Use in	See Section
Binding components	Establishes the connectivity between a SOA composite and the external world. There are two types: Service binding components provide an entry point to the SOA composite application. Reference binding components enable messages to be sent from the SOA composite application to external services.	The SOAP binding component service: Advertises its capabilities in the WSDL file. Receives the SOAP message from the .NET application. Sends the message through the policy infrastructure for security checking. Translates the message to a normalized message (an internal representation of the service's WSDL contract in XML format). Posts the message to the Service Infrastructure. An example of a reference binding component in Figure 1-2 is the Loan Process application.	Service Components
Service Infrastructure	Provides internal message transport	The Service Infrastructure: Receives the message from the SOAP service binding component. Posts the message for processing to the BPEL process service engine first and the human task service engine second.	Service Infrastructure
Service engines (containers hosting service components)	Host the business logic or processing rules of the service components. Each service component has its own service engine.	The BPEL process service engine: Receives the message from the Service Infrastructure for processing by the BPEL Loan Process application. Posts the message to the Service Infrastructure after completing the processing.	Service Engines
Universal Description, Discovery, and Integration (UDDI) and MDS	The MDS Repository stores descriptions of available services. The UDDI advertises these services, and enables discovery and dynamic binding at runtime.	The SOAP service used in this composite application is stored in the MDS repository and can also be published to UDDI.	Managing Shared Data with the Design-Time
SOA archive composite (deployment unit)	The deployment unit that describes the composite application.	The SOA archive (SAR) of the composite application is deployed to the Service Infrastructure.	Deployed Service Archives