In this chapter, I demonstrated how to implement web services using the Perl SOAP::Lite module.You also saw how XML is implemented in actual middleware technologies, using its data description capabilities to describe the messages and their data types. Using XML, we can easily transfer data types between two different machine architectures, as well as two different programming languages. This is one of the biggest advantages of XML as opposed to other data formats, and it is one of the reasons for the well-deserved popularity.
XML web services, although heavily advertised and discussed, are not even close to reaching their potential. Applications are only now beginning to take advantage of the web services facilities that are currently available. As we all know (especially with web-related technologies), the biggest changes happen for the better as the number of implementations increase and people gain experience working with the technology. We can only imagine how web services will transform information sharing between applications.