Chapter 19. Web services introduction
Introductory Discussion -
Communication protocols -
Service discovery -
REST -
XML Signature If you are involved with information technology – and haven't spent the last five years installing Wi-Fi access points on Mars – you've heard of Web services. In fact, you may have heard of it in breathless terms as a "revolution". The last time there was so much revolutionary talk in the air, there was also tea in Boston harbor. You can understand the hype if you look back at recent history. Before the Web, it was very difficult to distribute information so that anybody could access it using any computer system. The Web standards made computer-to-human communication easy and automatic. XML has begun to make computer-to-computer communication easier as well. Web services is trying to go further in this direction. It is a term for services supported by a new set of XML-based protocols intended to make computer-to-computer communications not just easy, but standardized and automatic.[1] [1] These services are sometimes referred to by Microsoft as XML Web Services, no doubt to distinguish them from the general class of Web-based services – such as online psychic readings! However, the rest of the IT industry, with its usual aversion to the precise use of English, seems happy with Web services alone. So despite the ambiguity, we too use the shorter term. | 
