IBM, Microsoft. and other vendors that have been pounding the Web services drum for more than two years claim that more and more of their customers are building Web services. And to a degree, they're right.
But the spotty levels of adoption by corporate users was plainly evident in a random poll of 15 IT professionals at Gartner Inc.'s recent Application Integration and Web Services Summit in Baltimore.
Some had taken a service-oriented development approach that yielded a growing collection of Web services. But more said that although they think it's the right direction, they're just getting started, with few or even just one Web service in production. Others expressed skepticism about the prospects of Web services to address their complex integration woes.
"I don't think the infrastructure is in place to enable the throughput," said Piet Potgieter, an application architect at Old Mutual PLC, a financial services and insurance firm in Cape Town.
Potgieter, who works with mainframes, said Web services may have their place where response time doesn't matter. But in his opinion, latency problems will need to be resolved before Web services can handle high throughput across a network.
Jonathan Pettus, a manager in the integration project office at NASA's Marshall Space Flight Center in Huntsville, Ala., said he can foresee Web services being useful for information exchange with the public. For instance, NASA next spring plans to advertise job openings through Monster.com and use a SOAP adapter from SeeBeyond Technology Corp. to enable rÈsumÈs to get into its back-end systems through a Web service, Pettus said.
But he said NASA has no plans for a full conversion to Web services to get internal applications to interoperate. "How long is it going to take us to get the thousands of applications that we have in NASA Web-serviceable?" Pettus said. "That's not going to happen."
Gartner analyst Roy Schulte estimated that 95 percent of the Web services being done today are internal between single-vendor systems on the client and server sides. "You don't mix vendor SOAP stacks in 95 percent of the cases because they don't work together if you're trying to do anything fancy," he said.
Schulte added that there won't be "pluggable interoperability with no customization, except for the simplest of applications," for at least five years, since vendor implementations will continue to vary.
He also predicted that Web services between heterogeneous systems over HTTP in high-throughput, low-latency scenarios won't be possible in the foreseeable future. But simple SOAP-based request-and-reply messages over HTTP work today, and reliable messaging and security will improve, he added.
The Web Services Interoperability Organization, led by IBM and Microsoft, has been working to resolve the thornier issues. In the meantime, companies committed to Web services are working around the limitations.
Gary Lien, a system architect at Life Time Fitness Inc. in Eden Prairie, Minn., said his company's external Web services are of a single-partner nature, so it is able to deal with security. Life Time gets around the issue of reliable messaging by doing only synchronous communication, he added.