At the help desk, having client configuration data on hand makes helping users faster and less frustrating. "Without it, we would either need a large manual effort to collect that information in advance, or the help desk technician would have to ask a lot of questions each time a user calls," says Moriarty.

The mapping data also helps ING pinpoint problems with its servers. For example, the company recently identified the cause of the failure of a scheduling agent on a server at its Hartford, Conn., data center. It had been inadvertently configured to act as a forwarding agent for data flowing between the Atlanta and Denver offices and was overwhelmed with traffic. Without autodiscovery and mapping, much greater effort would have been needed to solve the problem, says Moriarty.

"Before, we would have to put network monitoring equipment on the data lines in and out of our data centers and track the transmissions at a very fine level of detail to identify where they're coming from, the nature of the transmissions and the volumes," he says. "This is just more efficient."

Application-mapping tools have similar purposes, but they differ in how they detect applications. Another differentiator is how many common commercial applications, such as Oracle Financials or Microsoft Exchange, they can map quickly via templates or blueprints of the applications' main components.

"The real differentiator is how well they pick up application stuff, and that's a factor of how many blueprints they have," says Gartner analyst Ronni Colville.