While some are concerned about bombs on airplanes or bioterrorist attacks on our crops, information technology experts warn Iowa businesses need to beef up security “firewalls” of their computers. Larry Brennan is critical infrastructure assurance coordinator for Iowa’s Homeland Security office. He says computer systems need to be patched and updated, that they have good authentification systems are in place, users are using good passwords — the security basics. Brennan says virtually -any- business in Iowa could fall victim to so-called cyber-terrorism. There are many vulnerabilities and many hackers lurking out there. Brennan says any business that depends on I-T systems to perform their services and stay in business, “absolutely, they’re at risk.” Nate Fagen is an I-T professor at Des Moines Area Community College. Fagen says the sniper situation in suburban Washington D-C is a good example of why computer users need to be prepared for a problem before it happens. Brennan and Fagen are giving a presentation at the Iowa ITEC conference, a two-day technical trade show which opens today in Des Moines.