Two technology trends that have been taking place separately in K-12 and higher-education institutions across the country are now beginning to come together: (1) the proliferation of wireless networks, and (2) the convergence of voice, video, and data on a single network infrastructure.

When considered on its own, each trend makes sense in terms of cost and convenience; now, as new technologies continue to improve, some schools are combining the two efforts.

Driving the trend toward wireless is the desire for always-on access. As students make technology an integral part of their lives, they want access to a network wherever they are on a campus–whether they’re in class, in a cafeteria, in an auditorium, or outside on the green.

“There’s the whole notion of wireless on campus, with people saying, ‘Gee, I’ve got it at home, why not on the third floor at the library?'” says Casey Green, founding director of the Campus Computing Project. “Schools are hearing it from both teachers and students”

Economically, too, converging disparate infrastructures into a single wireless network makes sense for some schools. “A typical three-story campus building would cost between $80,000 and $150,000 just to string and terminate wires. We could deploy wireless for about 30 percent to 50 percent of that cost,” says Brad Noblet, former CIO of Dartmouth College. Under Noblet’s guidance, Dartmouth developed one of the industry’s first totally converged wireless IP networks.

Converged wireless at Dartmouth

Before Noblet came to Dartmouth, he had been involved in a number of start-up technology ventures. He had confidence that not only was convergence possible; it was essential. Interestingly, convincing decision-makers at Dartmouth that convergence was necessary was a walk in the park.

“It was simple to prove that [the cost of providing] voice over IP and video over IP was a fraction of what it would cost to build out separate infrastructures,” he says. “It was the wireless piece that was viewed as still new.”

At the same time Noblet was hoping to convince Dartmouth administrators that wireless would benefit the school, some interesting developments occurred. The college had over-extended its admissions and was scrambling to build temporary housing. Because the school was in a bind, there was no time to have contractors install and terminate wires. Instead, the college deployed wireless networks in those buildings.

“Not only did we save money, but we were able to do it in just a couple of weeks,” Noblet says. The wireless networks delivered data, IP telephony, and cable television. “We were able to show that if we were to deliver these converged services, plus normal applications, in a converged format, [the students’] quality of life would be enhanced greatly,” he says.

That’s when Noblet got the green light to deploy converged wireless ubiquitously across campus.

Dartmouth had a legacy Wi-Fi network in place, with more than 550 Cisco 350 802.11b access points. But each access point had to be configured individually with user names, passwords, firmware updates, and so on, and it just wasn’t an easy interface to use.

Noblet helped Dartmouth construct a wireless network densely populated with access points from Aruba Networks. These access points are controlled with Aruba 5000 wireless LAN (WLAN) switches–each of which supports hundreds of access points, thousands of users, and gigabits of encrypted throughput.

Two elements were of utmost importance to Noblet and Dartmouth. The first was security. Noblet wanted to ensure that everyone who needed network access while on campus–students, faculty, other staff, and even visitors to the school–would be able to have access, but there were various levels of security that needed to be considered. For example, staff members who needed access to student records or payroll information would need to have one level of security, while guests who just wanted to get online would need another. Noblet wanted Dartmouth’s network to allow the appropriate level of access based on the identity of the user.

Working with Aruba, he developed a system that allowed for individual, certificate-based tokens that carry a user’s credentials. Aruba employs the 802.1X security protocol, which allows for the support of these tokens. Dartmouth’s network now can virtualize the 802.1X protocol for the entire network and deliver universal authentication on any port, without having to touch each network switch or disrupt current network operations.

“People with a user name and password can get [access], and it [also] allows people who just want to get to the internet to get on,” says Noblet of the school’s network.

The other important element–and one of the biggest challenges of implementation–was mobility. Dartmouth needed more wireless bandwidth to support video, voice, and data, as well as access for students and staff in any area on campus they wanted to connect.

“But in order to have more bandwidth, the only way to do that is to put in more access points,” says Noblet. “The problem or challenge with putting more access points in a given area is keeping them from interfering with one another and then being able to effectively load-balance, or spread your users across the access points that you just deployed.”

Dartmouth’s solution: “switched” wireless connectivity.

The Aruba 5000 WLAN switches allow Dartmouth to maximize capacity by directing users to access points that have more free capacity than others. Previously, the network required each user or device connecting to the network to decide which access point it was going to connect to, while knowing nothing about the total capacity available.

“The wireless switch can now interject itself to say, ‘No, you don’t want to go there, you want to go here,'” Noblet says.

The switches also mean Dartmouth administrators don’t have to go to each access point to reprogram it individually when needs arise. “You can do that from the central controller, and it sends information to the access point. When you’re putting in many access points, you can’t really do it by hand anymore,” Noblet explains.

All told, Dartmouth deployed 12 Aruba 5000 WLAN switches and more than 1,000 single-band 802.11a/b/g access points and 70 dual-band access points. And the college is using its wireless network for voice and video applications as well as data.

For voice service, Dartmouth has deployed 75 Cisco 7920 VoIP phones for faculty and staff, 800 Cisco IP Communicator soft phones, and 125 Vocera badges. More than 4,000 telephone lines have been converted to VoIP service. Faculty and staff use the Vocera badges to locate colleagues on campus quickly, as well as to help others outside the school locate them. When someone calls a Vocera phone number, the system uses voice recognition to pinpoint the target badge in order to route the call wirelessly to the right IP address.

For video distribution, Dartmouth uses servers from Video Furnace to convert cable TV channels into MPEG video streams that can be multicast to laptops using client software agents. When a student signs up for access to a channel, he or she is added to an IGMP multicast group for that channel. Because each computer needs 400 kilobits per second to 2 megabits per second to screen video content, efficient use of bandwidth is essential. Any given Aruba access point reportedly supports four or more simultaneous MPEG data streams.

“Dense deployment of Aruba access points gives us the performance, coverage, and scale that make this project even possible,” says David Bourque, a network engineer at Dartmouth College.

North Carolina district chooses microwave wireless

Dartmouth College created a converged, campus-wide network using switched Wi-Fi (802.11) radio-frequency technology. North Carolina’s Iredell-Statesville Schools, a public K-12 school system serving some 18,500 students, took a different approach to designing a network that could deliver voice, video, and data wirelessly to its 35 schools and four central offices, deploying a microwave network from Conterra Ultra Broadband.

Microwaves, a subdivision of the radio spectrum, easily can supply the considerable bandwidth it takes to support voice, video, and data over a single network infrastructure. But they only work on a “visual” basis–that is, there needs to be a clear line of sight for the radio waves to traverse, because microwaves cannot penetrate barriers. For this reason, microwave technology is useful as a conduit for wide-area networks, providing connectivity from building to building, but not for ubiquitous connectivity inside and outside a school.

Microwave technology “could give us dedicated 100 megabits-per-second [connectivity] between sites, and the best we could get out of our wired provider was 75 to 100 burstable [megabits per second], and we didn’t want that. We wanted the full 100,” says Pam Schiffman, chief accountability and technology officer for the district. Schiffman knew the district eventually wanted to support video streaming, video conferencing, and VoIP service, among other things, so district officials chose to implement the wireless plan.

The installation began in March 2005 and progressed in phases. By July 2005, seven sites were connected wirelessly. The second phase was completed in November of that year, and by May 2006 all the sites were connected.

Until the district built out its wireless WAN, it had been relying on T-1 lines to connect most of its schools. With its microwave network in place, data-transfer rates between buildings are about 65 times faster than T-1 speeds.

Planning how to engineer and design an optimal wireless network that meets current and future needs and maintains a high quality of service was important. For the Iredell-Statesville Schools project, Conterra conducted a Line of Site (LOS) Path Analysis, using 20 different attributes to determine the best microwave paths between schools and office facilities. Then, antennas were erected with licensed microwave radios to transmit and receive signals at each location.

In the case of Iredell-Statesville Schools, Conterra designed a ring network topology that incorporated three rings into the network for redundancy. To connect the schools and central-office facilities together, the company erected concrete utility poles ranging in height from 100 to 140 feet. These poles resemble the light poles often found in school parking areas. The three-ring network then connects back to the main aggregation site at the district office.

To ensure a high quality of service, all Iredell-Statesville facilities have service-level agreements that guarantee speed and reliability levels equal to or, in some cases, better than fiber-optic connections.

The transition to the new network has occurred seamlessly, Schiffman says, with teachers, faculty, and staff being unaware of the switch. Though they realize a change has been made because of the ease and speed with which they can access the internet, as far as the technology behind it goes, “they don’t know the difference,” she says.

Although all sites have the capability now to deploy VoIP service, they have not made that switch yet. “That’s in the future,” Schiffman explains. “Our issue with that is the price of the phones. They’re very expensive.”

The district has taken sort of an “if you build it, they will come” approach to its network: Now that the capability is there, the teachers are using it, Schiffman says.

“What we’re finding is, [our teachers] are increasing their visits to internet sites for instructional purposes,” she says. “We have more video streaming going on. We have distance learning, with students who are [attending] virtual high school. It’s opened a whole new world for some of our students and some of our teachers.”

One district reaches for convergence

Deploying converged wireless networks in a single swoop across entire campuses or districts has proven useful and cost-effective for some institutions, but others–such as Maryland’s Montgomery County Public Schools–have chosen to move more slowly.

Some of Montgomery County’s schools have wireless 802.11a/b/g networks, and the district’s central office for technology innovation has been equipped with wireless technology as well. But Montgomery County has chosen not to implement a wireless system throughout the district, for now. “There are expenses that we have to look at–the issue of bandwidth, speed of access, security,” says John Q. Porter, deputy superintendent of information and organizational systems.

Porter has, however, put in place a strategic plan for moving forward with converged wireless service in the future. He says he’s researching a growth strategy to migrate to 802.11n technology and increase wireless bandwidth. The district’s wireless plan ultimately will include converged solutions such as voice over wireless, unified communications, and streaming video.

Porter also is being ultra-careful about security. “We’ve been conservative about this. Some are bolder than we are. Our administrative systems are not run through wireless. For that we’re using fiber. We’re using encryption for some of our wireless labs to see how it works,” he says.

All of the district’s new schools, renovated schools, and “test sites” (sites for training and testing of new technology) have wireless capability. Some schools, for example, have IP cameras whose images can be downloaded wirelessly to handheld computers, providing real-time video streams to school security personnel as well as local law-enforcement officials. Some schools also have VoIP service, and Porter has allocated close to $1 million to get VoIP service in the central office.

“It’s expensive,” he says of VoIP service. “You lose, in some cases, in terms of eRate money. There’s more efficiency, but it’s hard to determine how much money you’re saving.”

Part of the difficulty in getting funding approved for these projects is that the district’s current telephone system and wired network still work. “If we say, ‘We’re going to trade [to a new system] and it’s going to cost us to trade,’ it’s hard to get the budget people to agree,” Porter says. “Our phones already work, so why do I need another phone [system]? Unless you have an enlightened board…”

One way to convince school board members is to talk about the benefits of a new system. “I’m not doing it for the savings. I’m going into it because I’m going to have greater efficiency,” Porter explains. “It’s really about converging those technologies and having access to everything at your desk or at your laptop. That, to me, is the value of it. The phone becomes that much more powerful to you, as well as any other device that you’re using.”

One of Porter’s ultimate goals is to provide a means of receiving all communications wirelessly on a single, mobile device–particularly for administrators and other staff members on the go. “We’re talking about being able to get video on any device you might have, using a telephone to get eMails, have eMails read to you, send or receive images from IP cameras on phones or on a [personal digital assistant]–all delivered to you and converged on one device,” he says.

Porter cautions school leaders not to underestimate the cost of the infrastructure and the training necessary to guide the process internally. “As with any implementation, change management is key,” he says. “We start change management the same day we start designing the implementation. You can never over-communicate, never over-train. You have to overcome [users’] fears, tell them the benefits, how it’s going to be used, how you can be successful in the use of the technology.”

That, he says, is where many school systems fail: “They don’t spend as much time on change as they do on the implementations themselves.”

Porter’s cautious approach underscores the need for schools to have sound strategic plans for implementing wireless technology. And there’s evidence to suggest that more school leaders are realizing this: More than two-thirds (68.8 percent) of campuses participating in the Campus Computing Project’s annual Campus Computing Survey last year said they now have a strategic plan for wireless in place. That number is up from 64 percent in 2005 and just 53.3 percent in 2004.

Regardless of how quickly schools move toward wireless solutions, one thing seems clear: As next-generation applications and devices continue to emerge, such as cell phones and handheld devices that integrate audio, video, eMail, and more, converged wireless is likely to play an increasingly important role in schools’ strategic plans.

Jennifer Nastu is a freelance writer living in Fort Collins, Colorado. She writes frequently on technology in education.


Aruba Networks

Brandeis University

Campus Computing Project

Cisco Systems Inc.

Conterra Ultra Broadband

Dartmouth College

Iredell-Statesville Schools

Montgomery County Public Schools

Video Furnace

Vocera Communications

Jennifer Nastu is a freelance writer living in Fort Collins, Colorado. She writes frequently on technology in education.