Web Services

Computerworld - As more and more companies seek to conduct significant business over the Internet, they face the problem of making their applications work with those of their customers and suppliers.

The difficulty with this type of integration isn't that it's hard to get applications to send data and instructions to one another—you just decide on a common standard, write any needed converters, and that's it. But as the number of applications goes up, the number of possible communications paths increases much faster.

Standards for Web Services SOAP Simple Object Access Protocol Allows applications to pass data and instructions to one another. For more information, visit the World Wide Web Consortium's site. WSDL Web Services Description Language Allows a Web service to be described so it can be used by other applications. UDDI Universal Description, Discovery and Integration Allows a Web service to be listed in a directory of Web services so it can be easily found.

Until recently, the only solution to this problem was to go with a middleware product. For example, the Windows operating system, which you can think of as a very successful middleware application, provides a common messaging environment for much of today's desktop software.

But suddenly, all of those middleware vendors (including Microsoft Corp.) are scrambling furiously to position themselves to survive what's about to be a big shock to the current system: Web services.

Web services are applications that use a universal language to send data and instructions to one another, with no translation required. And they use the Internet, so most of the connection problems are eliminated.

So far, the Internet has been used primarily in a people-centric way. Applications send out data for humans to read through Web browsers. If another application is on the receiving end, it has to "scrape" the information off the screen (a task bound to fail as Web and application designers change page layouts and move elements around), or it has to use a dedicated back channel.

An example of a company using both strategies is Yodlee.com Inc., a Redwood Shores, Calif.-based provider of financial account aggregation services to banks and portals. Yodlee either scrapes your checking and credit card balances off Web pages by logging in and pretending to be you, or it asks each financial institution individually to send it the data.

It's a slow process. And just the kind of thing Web services could handle better.