Because each connection among systems had to be coded manually, first-generation middleware was also very inflexible. If a mortgage company wanted to change the maximum age for a borrower from 60 to 70, for example, there was no way to make the change in one place and have it cascade through all affected data. As a result, maintenance of systems connected by middleware was expensive.

And the companies’ investments of money and time made it easy for their vendors to sell them multiple products and services. "They used middleware to entice you in," recalls Sanderson, who has used various middleware products for many years. Once you committed to one vendor’s platform, it was tough to change and there was every reason to keep buying more from that one company.

But during the 1990s, the drumbeat of standards began to grow louder. Customers started to push software vendors to offer application programming interfaces (APIs) as backdoors into their closed environments, thus making integration easier.

Then the Internet took hold, with its plethora of data transmission and access standards, including HTTP, FTP, simple object access protocol (SOAP) and XML. The last of these set the stage for Web services, a relatively simple, standardized way of integrating applications. The goal, ultimately, is to go beyond simply linking applications loosely together, but instead to integrate pieces as needed, quickly and easily, thereby creating "composite applications."

For their part, middleware vendors voice support for standards in the same breath they defend their proprietary value-add. "Standards reduce our development cost," says Ram Menon, senior vice president of worldwide marketing at Tibco. "XML is a normalized format. It will get the data moving, but the applications still can’t talk to each other."

It’s hardly surprising that vendors are trying carve out their own special place in this volatile, near $1 billion market. But they make some moves grudgingly. "If you’re BEA, you still don’t want your stuff to be used in an IBM project. If you want to connect BEA to IBM, you can do that thanks to standards, but you can’t expect BEA to be happy about it," says Gerry Cohen, president and CEO of Information Builders.

"The large vendors are seeing the benefits of being open. They’re not 100 percent there, but they are much more open than they were," adds Barney Sene, vice president and CTO for WellPoint, a $20 billion health insurance company. The nation’s second-largest health insurer, WellPoint uses IBM’s MQSeries Integrator middleware to form a bridge between the legacy systems that process member claims and the Web-based, IVR and EDI customer-facing systems so that its employees can better serve customer needs.