A record-breaking number of students attending Iowa State can be a positive aspect of campus life but can also lead to problems. Due to the large number of students, many had difficulty connecting to the Internet at the beginning of the semester.

“What may have appeared to have been a wireless problem wasn’t actually a problem with the wireless itself, but the way IP addresses were handed out to users,” said Jennifer Lohrbach, systems analyst for Information Technology Services.

The campus wireless network is an intricate system that cannot become overloaded or else students will experience difficulty with signing on.

“To use the campus wireless network, your device must connect to a wireless access point and then be assigned an IP address,” said Angela Bradley, director of systems, operations, network and communications for IT Services. “On the first day of classes, devices were connecting to the wireless access points, but the system that assigns addresses, the DHCP server, was overloaded. The DHCP system was designed to handle about 75 requests per second. It was receiving 300 to 400 requests a second.

“After some configuration changes late Monday, Aug. 23, the DHCP problem was resolved.”

The Network Infrastructure, Authorization and Directory Services team is the IT Services group that analyzed the problem and came up with the solutions for DHCP. The Network and Communications team is performing site surveys, installing jacks and placing access points for better wireless coverage.

“There was a huge increase in the number of wireless subscribers on campus this fall,” Bradley said. “We are seeing about 60,000 devices on the network, and between 55 to 60 percent are wireless. Our DHCP system was not prepared for 300 to 400 requests per second, but with the changes mentioned, we are ready for future demands.”

Anticipating future problems is an integral part of Bradley and the IT Services teams’ jobs.

“To better plan for future increases in load on the DHCP system, we have reconfigured a couple of things: Devices are given IP address leases for variable lengths of time to best meet mobility demands, and the IP address assignment is being done using a faster access method on the server. There was no cost at this time, but future upgrades will probably require faster disks and more memory,” Bradley said.

To plan for future increases in load on the wireless access points, there will be an upgrade to a protocol, the access points will be managed through a central controller, and there will be more overall access points on campus. The CAC recently awarded $1 million toward campus wireless expansion, and IT Services will fund this upgrade of existing access points.

“Because people on campus carry mobile devices as they move between buildings, the mobile devices automatically try to connect to the wireless access points, and our DHCP system tries to assign an IP address for each building they pass or enter. We have changed the time frame each device would keep the same address and also sped up the processing on the server,” Bradley said.

Students used to carry fewer Internet devices but now carry multiple devices such as a cellphone, laptop and an iPad, just to name a few.

“Students’ devices, as well as others’ devices on campus, are able to connect to the wireless network quickly and more efficiently now. This increase in service level also helps support the cases where people carry multiple wireless devices and want them all connected simultaneously,” Bradley said. “The wireless expansion will increase the connectivity speed and cover more public areas on campus.”

With this problem now fixed and Internet service intact, students no longer need to worry about their wireless connection.

“I did experience problems earlier in the year with Internet access. I think it is really important to have Internet access on a college campus, so I’m glad this problem was addressed,” said Thomas Thatcher, freshman in design.

Of course, improvement will eventually need to be made and the IT Services team is ready when this time comes.

“At some point, we will replace the DHCP server with higher-performing equipment. We are also investigating how the IP address ranges are allocated in buildings. Wireless equipment continues to improve in both speed and user support,” Bradley said.

“We anticipate that the demand for wireless will continue to grow, and we’re making investments to meet the campus needs. IT Services will continue to monitor wireless performance and provide network support and resources,” Bradley said. “We understand the importance of mobility to campus life.”