Best of both worlds

A few years ago, enterprise application integration (EAI) tools were considered state of the art in linking disparate computer systems.

EAI products promised to end the expensive nightmare of custom-coding links among isolated applications. In the 1990s, products by vendors such as Tibco Software Inc., Vitria Technology Inc. and webMethods Inc. became staples of many integration projects.

Then Web services arrived on the integration scene. Offering an integration approach based on open standards, Web services were touted as a cheaper and more flexible path to interoperability. Some observers mused that Web services might overrun traditional EAI products with their proprietary underpinnings.

But don't count EAI products out yet. They continue to serve a purpose and will endure as a building block of application integration, according to the technology's practitioners. They predict that EAI and Web services will coexist for some time.

Indeed, the two approaches can complement each other. In the government market, some industry executives believe EAI/Web services combinations will become the norm for integration projects.

That's not to say that EAI will remain unchanged. Many products already have adopted Web services standards for some integration tasks. The future for EAI appears to be in higher value-added areas such as workflow, business analytics and development.

Some technologists contend that those expanded capabilities may serve as the foundation for deploying and managing Web services. EAI "still has a strong relevance in the market," said Jonathan Hill, associate partner for enterprise integration and market intelligence at Accenture, an integrator with experience in EAI and Web services technology.

A continuing role

One traditional EAI role has been to link various enterprise systems through adapters or connectors. Adapters mask the differences among the native application program interfaces (APIs) of the systems an organization wishes to integrate. This EAI infrastructure provides a simplified alternative to custom-coding every link among systems.

Web services, meanwhile, provide a

standards-based version of application integration. Although EAI may use propriety methods to link applications, the Web services approach wraps APIs in Extensible Markup Language.

In this form of integration, XML serves as the message format, Simple Object Access Protocol (SOAP) provides the envelope for transport and Web Services Description Language (WSDL) describes the interface, said Jeff Mitchell, managing director in charge of enterprise integration services for BearingPoint Inc.'s public services practice.

XML, SOAP and WSDL "have allowed us to overcome a proprietary mechanism that EAI tools imposed," he said.

Web services are considered less expensive to deploy than an EAI suite, which can cost nearly $100,000, and have begun to attract a following of interoperability seekers. But EAI has been around longer than 3-year-old Web services technology and has solved many of the problems that continue to hinder the nascent technology.

The reliable transfer of messages among applications is one such problem. With EAI, the messaging layer guarantees data gets delivered. Such message brokers have found a home in government integration.

For example, the Agriculture Department's National Information Technology Center uses IBM Corp.'s brand of messaging middleware, WebSphere MQ. Douglas Hughes, an IT specialist at NITC, said IBM's technology manages "a lot of the integration between different applications on different platforms." The product helps integrate the USDA's state and local offices and NITC.

Security is another consideration in the EAI vs. Web services dialogue. "When you open up services for people to be able to access, you also open up some potential security issues," said Donald Bell, president and co-founder of Architech Corp., a software and services company. Industry analysts contend that EAI offers greater security than Web services.

In addition, EAI's tightly coupled integration makes the technology a better choice for linking complex, transaction-oriented applications, according to EAI advocates. Web services "start to struggle when they get into more complex usage patterns," said Steve Craggs, a vice chairman of the EAI Industry Consortium.

Suresh Chandrasekaran, senior director of product management at Vitria, noted that a heavy-duty integration framework is still required in highly transactional, high-security environments. Old-school EAI, he said, "is not necessarily going away."

Getting along together

Different as they may be, EAI and Web services don't have to be exclusive choices. In fact, the technologies may be viewed as complementary. Web services protocols for managing, monitoring and coordinating the activities of Web services components have yet to mature. But EAI technology can provide the missing infrastructure.

Web services deployments "with the most success will have an integration backbone — like an EAI tool — that does the lower-level things," said David Plesko, a partner and global leader for the enterprise integration practice at Accenture. He said EAI could address the guaranteed delivery and security issues, while providing a "framework for the orchestration and movement of data."

Web services, meanwhile, can boost EAI. Web services' push into the adapter space may prove to be more of a blessing than a curse. In some respects, EAI vendors are "happy to see Web services take over the adapter market," Hill said. EAI vendors have invested millions of dollars in adapters, some of which are used by only a handful of customers, he said.

Vendors who don't have to churn out adapters can afford to cultivate higher-level capabilities. The rise of Web services "provides an opportunity for integration software vendors to add additional capabilities that will help our customers deal with real management challenges at more of an operational level," said Kristin Weller, executive vice president of webMethods.

Customers can also reap the benefits of the integrated relationship, tapping Web services for connectivity and EAI for management, industry executives said. The use of Web services in combination with EAI will become the standard deployment during the next 12 to 18 months, Hill believes.

NITC will be among the government agencies dealing with traditional EAI components and Web services. Hughes said he expected the center's customers to begin deploying Web services next year.

In Florida, the state's Department of Children and Families (DCF) is deploying an EAI product that supports Web services, while providing transactional integrity, message reliability and monitoring features. The department beta tested InterSystems Corp.'s Ensemble software in 2002 and purchased the product in 2003. Integration is an important objective for the department, which has 300 systems and 60 databases. "One of the things that almost all businesses are trying to do is integrate data from different systems through a single view," said Glenn Palmiere, DCF's information technology director.

Such projects may cement the case that EAI and Web services are interlocking pieces of the same puzzle. "EAI is not a piece of software.... It's a collection of tools and techniques that enables applications to interoperate," said Michael Kuhbock, co-chairman of the EAI Industry Consortium. "Web services is a toolset within the EAI platform."

Agencies would surely benefit from one happy integration family.

Moore is a freelance writer based in Syracuse, N.Y.

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Integration checklist

Three key roles for traditional integration tools:

Serve as the integration glue for systems that organizations don't wish to expose as a Web service for security or other reasons.

Act as the method of choice for linking complex, transaction-oriented applications.

Serve as the integration framework for managing Web services.