Wireless mesh networking is not for everyone. But, when it makes business sense, it works the best.
Overall, a wireless mesh network is a communications network made up of radio nodes organized in a mesh topology. Wireless mesh networks often consist of mesh clients, mesh routers and gateways. The mesh clients are often laptops, cellphones and other wireless devices while the mesh routers forward traffic to and from the gateways which may, but need not, connect to the Internet.
The coverage area of the radio nodes working as a single network is sometimes called a mesh cloud. Access to this mesh cloud is dependent on the radio nodes working in harmony with each other to create a radio network. A mesh network offers redundancy. When one node can no longer operate, the rest of the nodes can still communicate with each other, directly or through one or more intermediate nodes – often it is called self-forming and self-healing.
Wireless mesh networks can be implemented with various wireless technologies. Often in the security world, the application is security video. But enterprises and government agencies are going beyond video.
One example is intelligent transportation systems (ITS). And that’s the successful deployment of a state-of-art wireless intelligent transportation system for the Scottsdale, Ariz., Traffic Management Center (Scottsdale TMC). The ITS communications platform connects wirelessly to video cameras, traffic signal controllers and dynamic message signs on arterials throughout the city, so experts at the Scottsdale TMC can continuously monitor traffic activity from a central command center. The ability to view live video feeds from heavy traffic areas enables city officials to make fast, well-informed decisions on how to prevent and reduce daily congestion, improve driver information and manage traffic affected by special events, weather and emergency
Smart City Application
Scottsdale TMC’s wireless ITS network consists of 90 wireless mesh nodes, network management software and 86 pan-tilt-zoom digital video cameras. To monitor traffic flows more effectively, the video cameras are strategically placed on traffic signal poles at intersections throughout the city and connect directly to the city's network via the wireless mesh nodes. Live video feeds of the most heavily trafficked intersections are continuously displayed on a large video wall and on desktop monitors in the command center, where operators can identify congestion and spot incidents as they happen – enabling them to take corrective action and remedy congestion.
Among the wireless mesh benefits:
- When collisions, spills or stalled vehicles occur, operators can adjust signal timing immediately to reduce the delay.
- The system enables immediate detection and reporting to police, emergency services, media agencies and the public.
- Costs are reduced by centralized traffic management and eliminating the need to deploy police officers at various locations.
- The ITS enables Scottsdale to keep travel time on city streets steady and even reduce travel time as traffic volume increases due to population growth.
Scottsdale is a forward-looking “smart city” that is focused on implementing technology to improve the city’s critical infrastructure while saving taxpayer money. Migrating from its existing leased-line communications network to the newly deployed wireless infrastructure mesh network will save the city approximately $250,000 a year in lease fees alone, enabling the city to achieve full ROI in only four years.
The wireless infrastructure network was selected because it proved to be the only solution that could deliver 100 Mbps of very low latency throughput while maintaining “low-sight” (less than 20 feet above the ground) wireless connectivity over long distances. Because the network supports up to 15 consecutive links, or “hops,” it can easily be routed around buildings and trees rather than requiring giant 300-foot towers to operate above these obstacles.
Integrator Ken VandeVeer of Sage Designs believes that wireless mesh is not everyone’s solution, but for his clients with water and waste-water districts and municipalities, it is a natural fit. “These utilities and their life safety needs run on the same mesh network.” With mandated security requirements, as well as inherent operational features, security is becoming more important in the utility sector, says VandeVeer.
Another real-world use of wireless mesh for security and operations spotlights transit applications. For instance, a project with the New York Waterway Ferry raises the bar in situational awareness and emergency preparedness. The NY Waterway has carried more than 65 million passengers and has been an essential source of redundant transit capacity in times of crisis, such as after the 1993 and 2001 attacks on the World Trade Center and the regional blackout of August 2003.
Because the safety and security of passengers has always been a top priority, the NY Waterway wanted a wide-area wireless network and security solution with a coverage area that encompassed almost the entirety of the waterways surrounding Manhattan. This particular geography presents significant challenges for many RF (radio frequency) technologies. Some of these challenges include water, ice, three major nearby airports, constantly changing sites lines, all in one of the most densely populated cities in the country.
Covers a Wide Area
Central to the solution is broadband connectivity in high-speed mobile environments. With it, the NY Waterway now has a high-speed wireless network with connectivity to all ports and ferries anywhere they operate. This wide-area wireless network and security solution has helped the NY Waterway improve communication, emergency response and preparedness throughout their fleet.
Another application centers on police and transportation dashboard and onboard cameras. In the past, it was cumbersome and expensive to handle recording. With wireless networking, the solution creates results from real-time viewing to ease of storage and retrieval.