Services at your service

Most companies looking seriously at SOA do so in hopes of making a  mishmash of existing hardware and software play together more smoothly. As Eric Pulier, executive chairman of SOA Software, puts it: “They have the AS/400, the mainframe, the J2EE server, and the hamster on a treadmill that can’t be replaced because everyone who wrote it is either dead or cranky.”

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Such companies have much to gain from SOA. But they face a key challenge in that heterogeneous environments bring together a plethora of brands, platforms, protocols, security systems, and more, making SOA standardization more difficult to achieve.

Even if the company’s chief architect solves the problem by dictating, for example, that all the company’s Web services will adhere to a specific security protocol, what happens when the company must change that protocol 12 months down the road? The Web services “policy” -- the set of requirements for using any given service -- must be abstracted from the services themselves in order for the SOA to scale.

This is exactly the type of practical concern for which we created the InfoWorld SOA Executive Forum, to be held in San Jose, Calif., on May 5 and in New York on May 17. (You can register here.)

“If you have exposed your applications as Web services but the security procedures and other policies are hard-coded into the apps, then every change requires you to re-code the apps,” Pulier says. “That’s equivalent to an old-style tightly coupled application-to-application interface.”

The smart solution is to handle such complexities in a service layer, integral to the SOA. Some companies write this layer themselves; others seek a prepackaged solution such as the one offered by SOA Software. In either case, the service layer knows where each service resides, what it knows, and what it needs. It then acts as a nexus for communication, security, and so forth. Upgrading a protocol, then, requires you to change the service layer rather than several apps.

“This becomes especially important when your SOA links together systems from multiple locations, partners, and even countries,” says Pulier, whose company is one of the sponsors of the events. “The rule of thumb is that your SOA is only as agile as your services are dumb. The service layer makes that possible.”

Finally, a word about this week’s cover. Both AMD and Intel released dual-core chips last week. Our cover shows the AMD entry midway through manufacturing, when transistors have been laid down, but without the connecting metal “wiring” on top. It also shows how good technology can be beautiful as well.