Terrorists, gangs and criminals are a constant threat to everyone’s peace and safety. In the fight against crime, private-sector security companies and domestic law enforcement personnel use video surveillance at strategic locations on city streets.
The U.S. government uses high-tech, Internet protocol (IP) video to detect illegal penetration of border areas and coastal regions. These video systems allow easy, cost-effective detection with minimal manpower.
In the past, the most common method of providing citywide connectivity for video cameras was to install fiber or coaxial cable from pole to pole. Today, wireless connectivity is preferred. The result is lower startup costs and faster deployment than is possible with traditional metallic and fiber.
Several radio technologies provide citywide connectivity for almost any kind of mobile application, including stationary video cameras. This connectivity collectively is referred to as a wireless local area network (WLAN). Two types in particular make it possible to send relatively high-resolution video from multiple locations to a central point where law enforcement can monitor the terrain for criminal activity: Wi-Fi (802.11) and WiMAX (802.16).
The 802.11 protocol communicates in single-node mode for a few hundred to 500 feet. When operated in a mesh topology, signals can be extended reliably 1,500 to 4,000 feet, depending on the application and the environment. Wi-Fi is readily available and provides multiple local access points at a relatively low cost. Best of all, using 802.11, video surveillance systems and other mobile devices connect and navigate a citywide network with little fuss, muss or loss of time.
The 802.16 format offers a fairly stable and robust solution for midrange use when establishing a metropolitan area network (MAN). The technology can be used to create a backhaul for a citywide WLAN. Individual Wi-Fi nodes connect to WiMAX, sending data back to a central server using WiMAX for backhaul. Here, the data is distributed so it can be accessed by one or more workstations. The backhaul is a channel of communication that offers sizable and reliable bandwidth over which a large part of network traffic is able to safely travel to a central server or point of use.
Without WiMAX or another comparable midhaul signal-transport technology, the mesh-operated Wi-Fi nodes would be forced to act as the backhaul, resulting in lesser bandwidth. This could result in signal delays, jitter, degraded transmission quality or other problems.
Another long-range transmission alternative is 802.22, also called WRAN, or wireless regional area network. This solution involves proprietary 3G (gigabit) and 4G radio solutions.
There are plenty of problems when building out a new citywide radio system. According to Byron Henderson, vice president of marketing with MeshDynamics of Santa Clara, Calif., some of the problems that network providers often experience involve network performance, right-of-way, network expandability, and deployment time.
Right-of-way is a problem for many cities, mainly because these entities often do not own enough cable infrastructures to make citywide radio cost effective on a wide enough scale.
Despite these issues, there is no denying that traditional Wi-Fi brings an accepted standard to the table and is designed into more mobile equipment than any other wireless technology, including video surveillance systems. This helps in deployment and increases the likelihood that the burden of cost will be shared willingly by a number of stakeholders in the common area.
A community’s need for wireless connectivity can be successfully combined with the needs of of government. Consider the town of Obregon, Sonora, Mexico. A citywide Wi-Fi system was installed there that covers 23 square miles. Stakeholders include the state- and federally owned Sonora Institute of Technology (ITSON) and the town’s population.
“Our goal is to enable the economy to be competitive nationally and internationally with the use of information technology,” said Jesus Gaxiola, IT director of ITSON. “Because we are fostering digital inclusion among the 270,992 inhabitants, a citizen-centered model was employed in designing the project with the individual as the core user of IT-based services from the government, education, health and private sector.”
In Obregon, the expense of ownership has been distributed effectively between the university and the community, making it more financially feasible and practical in the long-term to install.
When street-level video surveillance is installed in Obregon, the wireless connectivity likely already will be in place.
COLOMBO is a 35-year veteran in the security and life safety markets. He is director with FireNetOnline.com and a nationally recognized trade journalist in East Canton, Ohio. Reach him at firstname.lastname@example.org.