While New York City's mobile broadband network garners much attention concerning its ability to serve both public safety and multiple government agencies, Oklahoma City's Wi-Fi mesh network recently passed its third anniversary and is now the world's largest mesh network, handling more than 4 terabytes of data traffic a month and serving up more than 200 applications concurrently for multiple government agencies.

Launched in 2006 using Tropos equipment, Oklahoma City's mesh network—which operates in the unlicensed band — now covers 95% of the city's 620 square miles. The vision was to supply public safety with high-speed broadband service but now city departments including transit, public works and IT access the network using a slew of devices ranging from handheld devices, laptops, traffic controllers and video cameras.

The city estimates it has derived about $10 million in savings to date as a result of the network and its efficiency gains from new applications such as in-field reporting systems, GPS tracking and video monitoring. The city also has garnered significant savings from avoiding the use of commercial mobile data services, said Steve Eaton, information security architect for Oklahoma City.

"It's significantly cheaper than trying to purchase service using wireless data cards," Eaton said "No one offered the level of service that we needed."

The network is engineered to give public-safety users priority access and the best data speeds, Eaton said. After constructing the network, Eaton said the city received hundreds of requests to automate other city functions.

"We started looking at what could benefit from using Wi-Fi," Eaton said. "This was specifically designed for public safety, so we needed to test one application at a time to see what would benefit." The city had to make sure public-safety services wouldn't be impacted by other uses, since advanced QoS methods weren't available three years ago. Today, QoS for public safety is engineered into the network.

Oklahoma City is continuing to expand the network, taking remote locations that have been using older point-to-point wireless technology into the mesh network to offer better connectivity with less communications overhead, Eaton said.
The University of Oklahoma uses the mesh network to monitor atmospheric conditions across the metro area. Its Oklahoma City Micronet (OKCNET) leverages 36 monitoring sites mounted on traffic signals to capture weather conditions. The goal is to provide critical weather information for the daily operations of the city, generate new scientific research focused on weather conditions in urban areas and inform the public.

Down the road, the city may offer free Wi-Fi to city residents but continues to study what type of impact free users would have on the network, Eaton said. For many cities, free Wi-Fi was the original vision of muni-WiFi networks, but the economics and capabilities of these networks did not match the expectations two to three years ago.

"We're still learning and growing with the system," he said.