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Hacker defense should work from the inside out

Local companies working overtime to shield their computer networks from outside hackers shouldn't overlook another common threat: company insiders.

That was one of the warnings conveyed Wednesday by special agent A.J. Gilman of the Federal Bureau of Investigation in Tampa. Gilman, a computer-crimes specialist, held a breakfast seminar at the offices of data-center service provider Peak 10 Inc. to brief local businesspeople on the dangers facing their information systems.

While outside hackers remain a critical threat to corporate computer systems, crimes committed by company insiders account for about half of the computer-intrusion cases the FBI handles in the Tampa Bay area, Gilman said.

Such cases involve employees, customers or contractors who have, or had, some authorized access to a company's computer systems, Gilman said. One local case involved a disgruntled 32-year-old employee at GTE Corp., now Verizon Communications, who four years ago entered commands into three GTE network computers that caused the computers to delete information stored on their hard drives and prevented anyone from stopping the process. The resulting damage cost the company more than $200,000.

"You need to know who you're giving access to," he said. "It's not an easy job, but it's important."

Gilman also emphasized the importance of remaining vigilant for outside threats, such as worms and viruses, and "distributed denial of service" attacks. These try to block proper communication within a network or send a fusillade of digital data to slow or shut down a targeted network or Web site. The attacks can be hard to trace because they use multiple "zombie" computers whose owners don't realize their machines are being enlisted for illegal purposes, Gilman said.

The FBI remains vigilant for the risk of foreign or domestic terrorists attempting to combine a physical attack with an Internet-based one that tries to disable vital emergency services, Gilman said. He urged companies to stay current on the latest operating-system security updates and to isolate potentially sensitive information from widely accessible parts of their network.

Seminar attendee Darrin Guilbeau, president of Tampa Internet services company Silicon Advantage, said he was surprised at how easy it is to alert the FBI about a computer crime.

"I didn't know we didn't have to go through the bureaucracy," he said. "We can just call and get a local person."

_ Louis Hau can be reached at or (813) 226-3404.

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