December 19, 2000, 10:29 AM — In the short history of the Web, the key decision has often been which Web server to pick.
Today, for large corporations, the big decision has become which Java application server to choose. Selecting an application server is much more complicated than picking a Web server, but the experiences of early adopters provide some practical guidelines.
You can think of application servers as bridges, connecting the Web with existing back-end databases, transaction systems and business applications.
More technically, an application server gives you three things: tools to build applications as a set of software components; server-based programs to host, run and manage these components; and interfaces so the components work with an array of existing systems.
Java products are hosts, or "containers," for Enterprise JavaBeans, which are software components written to one of the APIs in the Java2 Enterprise Edition (J2EE) specification. J2EE, which will be released formally later this month, is being viewed by many corporate IT managers as the key to deploying larger-scale Java applications on the Web because of the additional services it describes, as well as its Enterprise JavaBeans programming model. This specification already is being implemented in application servers from an array of vendors.
A new report from Ovum, a London technology research company, predicts dramatic growth in the application server market during the next five years. Ovum analyst Gary Barnett predicts the high-end products will become "integration hubs" that will let corporations selectively grant access to internal business processes to certain outsiders, including suppliers, customers and partners.
Most corporate IT groups assess application servers as they do any other key part of the enterprise net: They perform a needs analysis; create a comparative features checklist; factor in prices; evaluate the vendor; and conduct testing.
But those who've deployed application servers say their experience shows some other key areas to take into account during evaluation and production.
Because the Java application server is being chosen for online transaction-oriented Web applications, it has to behave like the Energizer bunny: It must keep going and going and going.
"We decided on PowerTier [from Persistence Software] for a simple reason," says Larry O'Brien, a project manager at i-mind Education Systems in Mill Valley, Calif., which markets its Internet portals to public school systems. "They have battle-proven code in their applications server. Their PowerTier product grew out of an existing C++ product that we knew worked.
"When creating a server-side Java system, you rely on the Enterprise JavaBeans container [that is, the application server] to provide scalable reliability under load and during failover," O'Brien continues. "It's not a place for rookie code."