Networking & Wireless
Staying Ahead of Wireless Demand with 802.11ac
Faced with the ever-growing wireless needs of students and faculty, savvy colleges and universities are future-proofing their networks with the new 802.11ac standard.
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When it comes to wireless networks in higher education, most campuses have weak points: places where the capacity of the initial network design does not match up to the rapidly increasing number of devices seeking access. While more access points (APs) can help, many institutions are looking to the future with cutting-edge hardware and network revamps.
Their first step: taking advantage of the first wave of access points using the relatively new 802.11ac specification from IEEE, which promises greater throughput compared to devices based on its predecessor, 802.11n.
The differences can get pretty technical, but among other benefits, 802.11ac includes wider channels (80 or 160 MHz versus 40 MHz for 802.11n) on the less-crowded 5-GHz band; more spatial streams (up to eight versus four); and higher-order modulation. The 802.11ac spec also introduces a technology to support multiple concurrent downlink transmissions, referred to as "multi-user multiple-input, multiple-output" (MU-MIMO), particularly useful for devices with a limited number of antennas, such as smartphones and tablets, according to IEEE.
Campus Technology spoke with four networking pros about their strategies for the 802.11ac migration and their efforts to "future-proof" their networks against even greater growth in the next five years.
Taking Time to Redesign
At Illinois State University in Normal, IL, residence halls are a top concern because students keep bringing more smartphones, laptops, tablets, Xboxes, PlayStations, smart TVs, etc., to campus. "What that means for us is that the 2.4-GHz spectrum — 802.11g and 802.11n — was really saturated," said Ryan Johnston, interim director of infrastructure, operations and networking. "To have a reliable system in the residence halls, we had to look to the 5-GHz spectrum, and 802.11ac has a lot more bandwidth, more channels, and doesn't see the interference we are seeing in the 2.4-GHz space."
As it adds 802.11ac APs, ISU initially plans to target priority spaces such as dorms, the library and the student union, Johnston said, "but what we are really looking at is a design change. When we installed campuswide wireless years ago, it was with that 2.4-GHz mindset, so APs were spaced for that level of radio signal. It was before there was an iPad or an iPhone, so it would have been difficult for anyone, even if we had seen these devices coming, to truly believe and plan for this device explosion."
Although its wired network is predominately Cisco-based and its previous wireless network was from Meru Networks, ISU chose to work with Aruba Networks on its wireless refresh. "Between Aruba and Cisco, it came down to simplicity versus complexity," he said. In terms of provisioning guest network access, firewalls and security roles, ISU saw the Aruba solution as a little simpler and more manageable. "And with money being tight and staffing constrained, having it easier to manage is certainly a consideration," Johnston said.
Because of funding and procurement issues, he said, refreshing the ISU wireless network will take years, not months. "But that gives us the opportunity to reach out to all the areas on campus to discuss what their needs are. When we put in wireless the first time it was new," Johnston explained. Everybody knew they wanted it, and the networking team guessed where to put it in, but in reality the usage of those spaces has changed over the years. Some departments may have increased their use of technology in the classroom or the design of the space may have changed. "We have professors in 400-seat auditoriums who at the start of class ask students to open their laptops and take a quiz," Johnston said. "We have to address those scenarios."
ISU did a proof-of-concept test with the Aruba 802.11ac equipment in the library, and saw significant improvements in throughput. Now besides rethinking the network design in high-traffic areas, ISU also is identifying buildings that are less crowded and won't need a design change. "To speed up the process, we are putting the new APs in those small offices we know we won't need to rewire," Johnston said. "We can just swap in the equipment, get them the newer technology and prepare them for changes down the road." Meanwhile, he added, the student union will have the 802.11ac equipment installed in just a few weeks.
Getting Up to Speed
Ohio's Cedarville University has started adding Meru Networks' 802.11ac APs to support high densities of student devices in its campus chapel and cafeteria. The Christian institution requires daily chapel services for all students, and the room seats more than 3,000 people. "We had nine access points in there. It was woefully underserved," said David Rotman, associate vice president for technology and CIO. "Part of it was the number of access points, but also their capacity," he said.
Last fall, Cedarville swapped out those nine APs and added 11 more to bring the number to 20, all supporting 802.11ac. Since installing the new APs, the difference has been noticeable, Rotman said. "Previously I had trouble even getting connected," he recalled. "This morning I did a bandwidth test and was able to draw about 30 megabits per second of bandwidth. I have hit as high as 50 in that room. That is quite a change from having a connection that would be flaky and drop out on me."
The 802.11ac access points extend range and speed, even for 802.11n client devices. But the real noticeable difference will come as more students and faculty members have 802.11ac-compatible laptops, tablets and smartphones. "We are seeing about 5 percent of traffic coming from newer 802.11ac devices," Rotman said. "The laptops we bought for faculty and staff this summer are 802.11ac-compatible. We are starting to see it as more of a common technology."
"Future-Proofing" the Network
For Harry Zahlis, network coordinator at Fresno City College (CA), upgrading to 802.11ac boils down to not getting too far behind the curve in terms of technology adoption.
"As a network guy, you can get blindsided when somebody wants to implement a new technology, such as video surveillance on the wireless network," he said. He gave another example: Fresno City College is creating a learning lab with 60 laptops. "You could accomplish that by putting in a ton of access points, but you better hope you are not on [802.11b/g] in 2.4-GHz. You have three channels. One reason for looking at 802.11ac is that not only can I service more clients with one AP, I also am not dealing with just three channels," Zahlis explained. "So it is really trying to future-proof as best you can with the technologies as they are coming out. I don't want to be too far behind, and I want to plan forward."
Fresno City College has just completed a major network switch upgrade, he added. "From a physical infrastructure standpoint, we are in a good place. Our back-end infrastructure is in good shape to take advantage of 802.11ac as we ramp it up," Zahlis said. Fresno City College is two years into the deployment of an Aerohive wireless network, with approximately another 100 rooms to cover. "Our goal is ubiquitous wireless," he said. "As we buy new access points, they will all be 802.11ac, and as we see needs, we will deploy the ac where it is needed most. We will let the need determine where ac goes."
It's a similar story at the University of North Georgia, where users' ever-growing dependence on wireless connectivity has prompted IT staff to change how they plan for wireless networking, including 802.11ac. "Most institutions implemented wireless as a novelty or a convenience," said Chris Adams, director of network and telecom services, "but now it has become an everyday tool for classroom instruction."
UNG has rolled out 802.11ac APs in six major academic buildings across two campuses in its Aerohive-based network. The first deployments were in critical areas identified through problem tickets and anecdotal feedback. But the university is installing the 802.11ac APs even in areas where it doesn't need the higher throughput quite yet, Adams said. "Interestingly enough, the models we have been deploying have cost less per access point than the 802.11n access points we had been deploying," he noted. Internet access for students doesn't usually require the higher throughput, but in areas where faculty and staff need access to locally hosted services, application caching and e-books, UNG is exploring 802.11ac throughputs. In addition to the cost-effectiveness, the radios and the hardware on the 802.11ac devices are much stronger, according to Adams.
Having the new equipment in place means the university can add capacity as needed. "We can make the jump to ac speed with a simple configuration change," Adams said. "If we need to, we can increase those throughputs to the users."
