The Seattle Police Department will transform its small legacy outdoor wireless mesh network into an 802.11n-based...
operation that will cover a wide geographic swatch of the city for IP video surveillance without the need for the complex routing necessary in legacy mesh networks.
The department's current outdoor wireless mesh network consists of a handful of older-model Azalea Networks 802.11a/b/g access points, which are usually deployed around the city in a pair of high-tech Homeland Security command RVs. Each RV is equipped with an Azalea MSR1000 dual-radio indoor wireless router. The department also has a pair of MSR2000 two-radio wireless mesh routers and five MST200 single-radio edge devices embedded in IP video surveillance tripods.
“The equipment allows the two vehicles to talk to each other and be networked together, and we can deploy battery-powered cameras within range of either vehicle so that we can bring video in from the scene," said detective Monty Moss.
Typically one of the command vehicles is set up at the site of a major event, supporting cameras within 300 feet. The second command vehicle is then parked a block or so away, giving the team reach around a corner or through the buildings that are in the way, so it can add another camera, Moss explained. The command vehicles also collect wireless IP video surveillance feeds from third parties, such as nearby restaurants, to expand coverage of blind spots, he added.
Building a new outdoor wireless mesh network with 802.11n
That legacy network is limited by range and performance, but with two grants in the pipeline, Moss is eyeing a new batch of 802.11n-based outdoor wireless mesh network products that won't require a high-density deployment of routers to cover a large urban space.
The network technology will come from Aruba Networks, which acquired Azalea last year, rebranding the mesh product line as Aruba AirMesh. The line now includes a recently released quad-radio MSR4000 802.11n router—a high-powered device that can serve as the core of an outdoor wireless mesh network. Aruba also launched a new version of the outdoor MST200, a single-radio 802.11n edge router, as well as an updated MSR2000 dual-radio 802.11n outdoor router and an indoor MSR1200 dual-radio 802.11n mesh router.
The AirMesh line has true Layer 3 routing capabilities, known as Adaptive Wireless Routing, one of the key features Aruba sought in its Azalea purchase. The products also include Active Video Technology, a deep-packet inspection feature that identifies, prioritizes and buffers video traffic.
With the first grant, Seattle Police will deploy six cameras along with MSR4000 routers around the Columbia Center, the city's tallest building.
"Those cameras will be looking in rather than out," Moss said. "The main focus will be surveillance detection, but it will also give [other agencies and organizations] around the tower access to those cameras so we can help each other look for suspicious activity and respond to incidents.”
If the second grant is approved, the department will build a much more ambitious upgrade to its outdoor wireless mesh network with 180 MSR4000 routers deployed along Seattle's waterfront and throughout the city's downtown area.
"Instead of having an [MSR2000] on every block, we'll be able to spread that out [with the MSR4000 on every few blocks] and cover a larger part of the downtown. We were estimating an access point per block with the legacy equipment. That would give us a coverage area of about one-third of downtown. [The MSR4000] will at least double our footprint of coverage, if not more."
In that scenario, the Seattle PD would use the group of APs downtown to create a mesh network, so first responders from multiple agencies could access the cameras. The first mission of this expanded network will be to deliver IP video surveillance along the waterfront, but Moss said the network will eventually deliver a variety of wireless services for multiple government agencies.
"We'll be deploying cameras along the waterfront, and those will have to be accessed with the MSR4000 units because we will have harbor units or fire department or Port of Seattle police accessing those feeds from the water. So we need something with a strong signal on the waterfront,” he said.
"Because of Aruba's security features and the 16 SSIDs that can run per radio, now we can start bringing in other city agencies, and they can have their own SSID and their own network," Moss said.
In fact, that model can continue to be expanded. "I'm looking at building partnerships with other city and county agencies to develop a sustainment model. If the infrastructure already exists, it's as simple as adding fiber to some of the access points so the different agencies can have their own network,” Moss said.
Let us know what you think about the story; email Shamus McGillicuddy, News Editor.
Dig Deeper on Wireless LAN Implementation