Chapter 12. Accessing Maps Through Web Services
While publishing maps to the traditional Web for human consumption is definitely one of MapServer's most attractive features, you may also want to share your data so that other programs can use it. To do this, you'll likely want to take advantage of web services. Ethan Cerami gives a good definition of a web service in the introduction to his book Web Services Essentials (O'Reilly):
A web service is any service that is available over the Internet, uses a standardized XML messaging system, and isn't tied to any one operating system or programming language.
Similarly, Venu Vasudevan in his A Web Services Primer, defines a web service as "XML plus HTTP." See http://webservices.xml.com/pub/a/ws/2001/04/04/webservices/index.html.
The term web service typically refers to an Internet communication protocol between applications. Web services are built on the standard web HTTP protocol used for web browsing. HTTP is the transfer protocol coupled with XML as a communication language. These communication specifications allow the Internet to act as a communication network between applications—not just as a service for sharing web pages.
Web services are important because they play the integral part of interoperability between applications which were developed independently of each other and yet are able to communicate. The web services standards are independent of programming languages, operating systems, and platforms. They provide a standardized ...