When Bill Marion talks about wireless connectivity, he's not talking about an office suite in a small industrial park. He's not talking about the Starbucks near the green. He's talking an entire city.
Marion, information-services director for the Silicon Valley enclave of Milpitas, Calif., is the man in charge of an intriguing municipal project. The plan: to bring seamless 802.11 access to the city's mobile public workers — wherever they happen to be in the town. "Anybody that's out and about and has a need for data" is how he puts it.
Milpitas's new wireless infrastructure, known as a mesh network, is designed to give police officers, firefighters, and building inspectors, among others, access to crucial information at data speeds ranging up to five megabytes per second. The city, which will be wrapping up its rollout early this year, is just one of a number of municipalities — ranging from Philadelphia to Grand Haven, Michigan — that are turning to mesh networks to get wired.
The fascination with mesh networks is not limited to those that tax, either. In November, Motorola Inc. announced its intention to acquire MeshNetworks Inc. And business users, particularly at companies with offices spread across a corporate park or in several buildings within a neighborhood, are also looking into them.
The eyeballing is understandable. While both traditional wireless local area networks (WLANs) and mesh nets have limited range, mesh technology can be easily and cost-effectively expanded to cover a lot of ground. Experts say the networks can provide coverage over a few thousand square feet — or dozens of square miles. Unlike conventional radio and mobile phone-based data-communications systems, mesh nets generally don't have dead zones. They also process large chunks of data handily, making it a pleasure to get onto the Internet. The same cannot be said of cell-phone access to the Web.
Given the advantages, experts believe mesh networks may dramatically alter inventory management and logistics. Of some interest to finance types: mesh nets are a real money saver. Backers of the technology note that meshes simplify network deployment by eliminating the need to install access points with direct cable connections to the Internet. (With a mesh, all access-point backhaul traffic is sent over the air to a central station.) By getting rid of cables, companies can cheaply place Internet access points in hard-to-reach places. Says Craig J. Mathias, a principal at Farpoint Group, a technology-research firm in Ashland, Mass.: "It's possible to establish a clear financial advantage for meshes in many cases."
Danger! Car Wash Ahead
Mathias estimates that a typical indoor mesh can cost up to 25 percent less than an equivalent conventional WLAN. With an outdoor mesh, savings can reach almost 90 percent.
For the city of Milpitas, such savings are a windfall. The real value of mesh networking, says Marion, is that it's the only technology currently out there that provides high-speed data traffic across a whole municipality. While the Milpitas project does violate the golden rule of technology purchasing (never buy really new gizmos), Marion says he couldn't wait for an ideal wide area networking solution to come to market. The city's existing Cellular Digital Packet Data system, running at a top speed of 19.2K bits per second, was simply too pokey to support the transmission of photos, maps, floor plans, and other large graphics files. "We wanted our police to have access to driver's license photos," notes Marion.
The mesh in Milpitas, supplied by Tropos Networks, covers about five square miles and is supported by 32 access points (mounted to lampposts). The network, which went live last summer, connects the city's 30 police cars to the Internet, allowing cops to access data and standard PC applications on fixed touch-screen computers mounted on dashboards and in glove compartments.
Soon Milpitas's 18 fire trucks will be hooked up to the mesh net. The city also plans to connect its traffic cameras to the network, allowing firefighters and other first responders to view and evaluate an accident scene as they race toward the location. "The battalion chief would be able to see if they had a single-car accident or a six-car pileup," says Marion.
The rollout has run into its own share of bumps, Mesh-enabled computers drained car batteries. Several times, an automatic car wash stripped vehicles of their mesh antennas. At one point, Marion says, he couldn't understand why the devices in the city's police cruisers were having trouble linking to nearby access points. "We took a closer look and discovered that the antennas were placed in the shadow of the lightbar," he recalls. "That blocked the signal."
Local officials in some municipalities, including Philadelphia, plan to build mesh nets that will eventually supply Internet service to local businesses. Ken Dulaney, a mobile-computing analyst for technology-research company Gartner, believes the networks are well suited for businesses with extensive outdoor operations. Ports and railroad yards top the list. "They are places where you have to cover a lot of area and you can't run wire," explains Dulaney.
The technology also allows enterprises to blanket large indoor areas, such as office buildings, convention centers, sports arenas, warehouses, and factory floors. At the Computer History Museum in Mountain View, California, a mesh supplied by Firetide Inc. provides Internet coverage throughout much of the institution's 120,000-square-foot building. Mike Walton, the museum's IT director, says the mesh, which serves both guests and staff members, is capable of covering the museum's eight-plus acres of outdoor space. "If an outside group were to hold an event inside a tent in the parking lot," notes Walton, "guests would still have Internet connectivity on their handhelds."
Buses — a Testimonial
Despite the obvious benefits of mesh nets, the technology is far from perfect. A lot of that has to do with the mesh manufacturers themselves. Industry watchers say makers of mesh nets, including Tropos, MeshNetworks, Firetide, and BelAir Networks, continue to roll out different — and usually incompatible — products. This insistence on proprietary products makes it difficult for potential purchasers of those products. So, too, does the notoriously high mortality rate of wireless start-ups. Experts warn that early adopters of meshes could wind up stuck with networks that can't be expanded or upgraded — or even serviced.
Latency, too, could prove to be a problem. As more users log onto a mesh — and more data is relayed between access points — response times can slow. Since a mesh must carry both service and backhaul, bandwidth can vanish rapidly. To date, most meshes have been developed for use by a controlled number of users; no one really knows what will happen as the networks become more complex and are thrown open to the general public. Says Stan Schatt, an analyst who covers mesh networks: "All of these issues are giving people the feeling that the technology is not quite ready for prime time."
Still, the vast potential of these new wireless networks outstrips the drawbacks. The uses are endless. In Ports-mouth, England, for example, city bus stops are linked to a $6 million mesh network supplied by MeshNetworks. With the network in place, anyone at any bus stop in Portsmouth can walk up to a kiosk-mounted display and find the exact location of the next bus. "In England, most people consider buses to be old, dirty, smelly, and not to be used unless you have to," gushes John Domblides, team leader of Intelligent Transport Systems for the Portsmouth City Council. "The [mesh] system gives people the confidence that the buses are actually worth using."
John Edwards is a freelance writer based in Gilbert, Arizona.