Networking & Wireless

WiFi: Seeing Through Walls

A new 802.11n WiFi installation is helping an Illinois high school tackle the challenge of thick wall construction in its older buildings.

• By Bridget McCrea
• 05/27/10

Getting a strong WiFi signal can be challenging enough without having to worry about 5-foot-thick walls standing between your laptop and the signal source. But that's exactly what teachers and administrators at Lyons Township High School in La Grange, IL, were grappling with when trying to access the institution's existing 802.11g WiFi infrastructure.

The school's north campus was built in the 1880s, with major upgrades in the 1920s through the 1940s, according to Ed Tennant, technology director. Its south campus was built in 1950s. "When you look at the architecture and building methods used, there was a lot of steel, concrete, and brick," said Tennant. "The walls are 5 feet thick in some places. Signal propagation is a huge issue for us."

Up until last year, just getting enough signal presence and strength "was a nightmare," according to Tennant. "We were almost relegated to placing one access point per classroom to deal with the challenge." With classrooms averaging 30' x 30' in size--and with more than 230 rooms to cover--the idea of dedicated access points didn't make sense, Tennant said.

Add Lyons Township High School's libraries, study halls, labs, field houses, cafeteria, and gym to the list of areas where WiFi was being used, said Tennant, "and we just couldn't get the footprint to cover it all with our existing setup." The hardware-agnostic wireless management solution controlled the school's access points and covered them under a single interface but still required "entirely too many individual access points," according to Tennant.

To find a solution, Tennant and his team looked first at WiFi options from large companies like Cisco, Hewlett-Packard and Motorola. Tennant said the school also considered options from a few "smaller providers," none of which could provide enough signal coverage to penetrate the high school's thick walls and heavy-duty construction techniques.

It would be months before Lyons Township High School would find a viable solution. "At one point we thought we were going to have to keep on our path of adding wireless access points as we needed them," said Tennant. Not willing to give up on finding a better option, Tennant said he "kept his eyes open for better solutions." The diligence paid off when, after talking to the IT staff from a nearby school district about its WiFi solution, he discovered the Ruckus ZoneFlex 802.11n.

The system was particularly attractive, Tennant said, for its ability to extend WiFi signal coverage with fewer access points, ease of installation and management, and lower overall cost of ownership. "We [tried] the product in our environment and were pleased with the results," he added. "The trials, plus the 'live' customer testimonials from the other district, sold us on the solution."

Mike Vasich, the school's systems administrator, said initial implementation (which comprised three WiFi access points) took about 35 minutes, including security deployment. "We had everything configured and working within an hour," said Vasich. The challenges didn't crop up until the buildings' ages started to show--particularly when it came to powering up the various access points.

"Not everything is installed in the most ideal [fashion] yet," said Vasich. "We're located on one of the worst-performing power grids in the state. To solve the problem, we've been hanging the new access points off of a UPS." Since purchasing the system in October 2009, Lyons Township High School's IT team has set up 105 access points--it previously had 100 in place--including those that cover classrooms, the cafeteria, the pool, and the field house.

"We're using the same number of access points, but now we have the coverage that allows people to roam about the buildings on campus and have wireless capability," said Vasich. "In fact, on one of our campuses you can walk from building to building without losing connectivity."

To school districts in search of expanded WiFi capabilities, Tennant said, "Try out the solution first" before you buy and install it. "Use the trial to figure out which equipment will and won't work with your infrastructure and buildings," said Tennant. "Get in there and kick the tires and put the system through its paces. The salesman will tell you everything will work and cover your campus, but until you get in there and try it out, you don't really know."

With a successful WiFi deployment behind it, Lyons Township High School is now adding more access points in order to provide additional bandwidth for users in specific areas of the campus. The school is also looking for ways to add more devices and users. (The school currently allows only district-owned devices on its network and doesn't offer WiFi options for guests, students, or parents.

"We're getting a lot of requests from people who would like other accessibility options," said Tennant. "We can't give them unfettered access, but we do plan to go back in and add access for non-district-owned devices in the near future."