A software bug shut down University of Wisconsin wireless networks in many campus locations for about six hours Tuesday.

Around 11:45 a.m., a problem was first reported to the Division of Information Technology, according to DoIT spokesperson Brian Rust.

A bug was eventually discovered in the Red Hat Linux program that works in conjunction with routers around campus. The problem was resolved around 5:45 p.m., Rust said.

"What they did was reboot it, and that's when there was this brief outage that bounced everybody out of wireless," Rust said. "When it came back up, it was working; then it went back down again."

Rust said the second outage affected at least six wireless-accessible locations around campus since the grid uses similar routers.

"Apparently what happened for several of these sites, the routers weren't handling the traffic well," Rust said. "So they needed to do some fine tuning to that particular router and then bring up the system."

Rust said once the Help Desk fielded a "critical mass" of calls, the system was analyzed and classified as an "Impact 1" level problem, and technicians were sent to investigate the case.

The lengthy delay came not from actually fixing the problem, but rather pinpointing the location of the issue, Rust said.

"There are half a dozen or more links in the chain in delivering network service to your desktop," Rust said. "It could be your computer, it could be the wireless, it could be the network connection, or it could be the authentication system — so any one of those things could have a problem, and you would just see that it's not working."

Rust said DoIT used a "triage" behind the scenes Tuesday and put the wireless networks back in service as soon as they could.

"We would have liked to have it up sooner, but they worked on it as quickly as they could," Rust added. "Fortunately, it occurred while technicians were on duty."

Wireless networks that blanket 70 percent of campus buildings are 99 percent reliable, according to Rust, who added DoIT has not had a report of this magnitude in "a long time."

"What are you going to do when there's a utility outage? Yeah, it's an inconvenience, and we're sorry," Rust said. "We just ask people to be patient and trust us that we'll diagnose the problems and make sure it won't happen again."

Bruce Broker, a library services assistant at College Library, said the building experienced the outage all afternoon and provided students with library computers while the problem was being located.

"It takes far more time to figure out the problem than to resolve it, then a fairly short time once they figure out what it is," Broker said. "There were certain situations where people were trying to print things from their wireless, so in the computer lab we had the means of connecting their laptops up to our network to print things, so it wasn't as though there weren't other options."