Seeing the passive optical network

Five reasons to actively consider the fiber-based passive optical network
By: | Issue: April, 2016
March 28, 2016

Unlike wine or cheese, networks don’t tend to improve with age.

That’s why some higher ed institutions are looking toward a newer network technology called passive optical LAN. Unlike copper cabling that’s been in place for decades, a fiber-based passive optical network (PON) offers faster, cheaper and more secure networks compared to legacy systems.

Following are five reasons this technology is being seen on campuses.

1. Lower installation and maintenance costs than other systems

Because passive optical networks have fewer moving parts, they are more cost-effective to implement and maintain than both traditional equipment and “active” optical systems, says John Hoover, vice chair of the marketing committee for the Association for Passive Optical LAN.

An active system uses routers to manage signal distribution, but a passive optical network uses optical splitters instead of numerous routers and switch aggregators.

Fiber optics take up less space than copper-based cabling, Hoover says. So colleges and universities can reduce materials costs with a PON. That was a driver for Stony Brook University in New York, which installed passive optical in its Center of Excellence in Wireless and Information Technology in 2010.

“Because this hasn’t been done on campus before, we had to prove that it could be beneficial, without a high cost,” says Bin Zhang, associate director of computing services. “We saw this as an opportunity for a faster return on investment.” He adds that the system would provide more speed without adding to maintenance expenses.

2. Equipment and power reduction

In a traditional network, a building would have stacks of Ethernet switches in several campus buildings or in a data center. Passive optical technology uses small converters that are close to end-user devices, reducing the need for telecom cabinets and large networking equipment. This reduces power and cooling needs. When extended campuswide, the savings can be considerable.

In a solution brief on passive optical networks, Motorola noted that lower power and cooling requirements make the technology inherently greener than a copper-based Ethernet LAN. In a building with 3,200 networking endpoints, for example, passive optical results in a power savings of about 50 percent.

3. Higher security and uptime

The converged simplification of passive optical networks make them faster and easier to secure, and results in significantly less downtime, Zhang says. “Often, when you want high bandwidth, you may be facing the kind of security issues that come with downtime. But we found that’s not the case with passive optical.”

Early adopters were the Department of Defense and other federal agencies. “Fiber is inherently more secure, because you’d have to break into the fiber, and that’s a tough step to take,” Hoover says. “With copper wire, it’s much easier to just capture interference.”

Digital storage of student financial data, medical and health care information, and other sensitive records makes network security particularly crucial, he adds.

4. Wider, broader coverage

Traditional cabling can reach only a certain distance from a campus data center or from a telecom station. That can create a decentralized data structure or require the installation of more stations as a campus expands.

Passive optical has a broader reach that’s capable of connecting an entire campus on one fiber-based network, through the use of multiple terminals. There’s also a wider array of uses for the technology.

For example, Texas A&M University chose passive optical for its newly renovated Kyle Field stadium, opened in 2015. The network supports 100,000 concurrent connections, and the university’s IT network architect, Matthew Almand, says the decision came down to “future-proofing” the stadium. “There were some leaps of faith and there was a decision to be leading-edge with technology.”

It took some time to bring the stadium’s networking group up to speed with fiber as opposed to copper, but once the group embraced the learning curve, they felt more confident with the implementation, he says. “Sometimes it’s good to break out of your comfort zone.”

5. Pilot project capability

It’s possible to install passive optical without disrupting other telecommunications and internet infrastructure on campus. At Stony Brook, there are no interoperability problems in areas where passive optical and legacy systems intersect, says Zhang.

For example, there are some parts of the university’s Center of Excellence where students and faculty need an independent network to experiment with technology, such as computer viruses. Passive optical allows them to section off a piece of the network without affecting other operations, and they can use the main campus network at the same time, Zhang says.

Campus administrators may want to start with a small pilot project to test the benefits of the passive optical.

Hoover admits it can be difficult to justify the costs of replacing IT architecture, such as networking equipment, if everything is working properly and isn’t due for a revamp. But looking deeper at passive optical may help institutions prepare for the future.

“Colleges and universities are going to keep growing in their bandwidth requirements, and copper cabling isn’t going to meet those needs,” he says. “We think PON is really a step forward that will remove some of the network pain points for higher education.”


Elizabeth Millard is a Minneapolis-based writer.