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With the introduction of Services, XML, Java and the introduction of WSDL, WSIF there came other new supporting software products. Java had always depending on the Java Virtual Machine because it is essentially an interpreted language (but it can be compiled to machine language..).

The new supporting software products included the Enterprise Service Bus (ESB), the Business Processing Execution Language (BPEL) and the Business Process Engine.

BPEL was an XML language for grouping the execution of individual Services together. BPEL is sort of like a batch language. It provides If-Then-Else capabilities and can start a Service, send it a message, and handle the result. BPEL needs a Business Process Engine (written in Java) to execute. The nice thing about BPEL is that it is a configuration language that doesn’t require complex programming. It relies on the Services to do the low-level work. If a Services is an employee, then a BPEL document is the Manager telling who to do what and when.

The ESB was a solution for the problem of automating connections between different environments and doing any necessary translation. Many systems have different formats for their information and it made sense to create something in-between to translate the format and pass it automatically on to the destination. ESB is a Java program that does this using XML instructions. It is called a Service Bus because like a Data Bus in that it manages the transmission of information between two parties.

ESB, BPEL and the Business Process Manager/Engine along with several other components are typically bundled into a SOA Suite. The other components could be a Service Repository which is a directory of the registered Services or a Web Services Manager (WSM) which enforces certain security restrictions. What security you ask? Well suppose you have a Service that returns compensation from the Payroll system. You would want to restrict who could call that Service, right? The WSM allows restrictions to be defined so that doesn’t happen.

So now we have a Service Oriented Architecture Suite. That seems nice and tidy. Why would we need anything more? And that’s where AIA Foundation Pack comes in…