Chapter 4. Orchestrating BPEL Services

Interoperability between discrete systems and disparate systems is one of the major challenges for the IT industry and is mission critical for most organizations. Disparate systems provide distinct complementary business functions. Disparate systems are usually designed and deployed using distinct technology stacks. The IT industry has created web services to facilitate the interoperability among discrete and disparate systems.

The underlying foundations of modern web services are XML and HTTP(S). One may find some legacy implementations using simple text messages, or special characters such as comma- or pipe-delimited text messages. In general, web services are XML-based programs that interact over HTTP(S) with interfaces that adhere to the industry standards set forth in the Web Services Description Language (WSDL) from the World Wide Web Consortium (W3C).

The W3C's WSDL standard provides the guidelines to define message types, port types, ports, and...