Home   Cover Cover Cover Cover
 

Web Services

Question: Describe several scenarios in which web services could be useful.

Answer: In general, web services are useful when an application on one computer wants to get information from an application that runs on some other computer or when one application wants to give instructions to other applications. Here are a few scenarios:

  • A web service that returns the current exchange rate for currencies. It can be used by a bank application to compute the value of a money transaction that is given in a foreign currency.


  • Web services that return the price of a certain article and the number of items in stock. An application could find out the cheapest price of a certain article by asking several suppliers and by placing an electronic order.


  • A web service that tells whether a certain student has registered for a course. The access software for a computer laboratory could use this web service to verify that the student is authorized to use the lab.


  • A web service that is given an ISB number of a book and returns detailed information about this book. This could be used by book stores and libraries to obtain detailed information from publishers.


  • Web services that allow the remote control of house equipment. This could be used by an application that controls the heating of a house, the refrigerator or the air conditioning.


  • Web services that query a POP server for emails that are stored for a certain user. This could be used by an email client or by an application that searches the emails for certain words.

A rich collection of web services can be found on http://www.xmethods.com