Mesh technology earned its chops as the backbone of metro-area wireless networks for municipalities -- transmitting...
data from traffic signals and parking meters -- but it has found footing in the enterprise space as well, taking its place as a Wi-Fi backhaul option when Ethernet jacks are sparse.
"Most enterprises are using wireless mesh as a wireless extension cord," said Paul DeBeasi, senior analyst at Burton Group Inc. "The mesh is simply an extension of their wireless networks into areas where it's inconvenient or too costly to do a wired backhaul [because] the throughput diminishes fairly quickly as you add more hops."
The strength of mesh technology also embodies its limitations. Wireless mesh technology allows nodes to reroute a blocked signal path by leapfrogging across other nodes. But each time a signal hops between mesh nodes, it cuts throughput to "one over the number of hops," DeBeasi said. Two hops, for example, would cut throughput in half. For three hops, it is cut by a third.
But wireless mesh networking can make sense for campus environments -- universities, hospitals, sports arenas, hospitality, airports -- where it's expensive, impractical or impossible to rip open ceilings, floors and walls to install data cables.
Meanwhile, not everyone is certain of wireless mesh networking's inherent limitations.
"There's no conflict between throughput and mesh. That's the first argument people use against it … [but] there are some mesh nodes out there that lose absolutely minimal bandwidth," said Craig Mathias, principal analyst of Farpoint Group. "There's no hard and fast rule about this. If you've got cable or fiber or wire installed, then I would use that to solve the problem, but if you don't you could use mesh."
Wireless mesh networking extends enterprises' reach
Tourists can tan on the beach, indulge in piña coladas at the bar or lounge in their hotel rooms and get 802.11n Wi-Fi access anywhere around the 21 properties that Sandals Resorts operates across the islands of Jamaica, St. Lucia, Antigua and the Bahamas.
Using Ethernet for wireless LAN backhaul was out of the question for Sandals Resorts because most buildings in the Caribbean are built with concrete and steel -- versus drywall -- making the installation of cables nearly impossible, said Bobby Stewart, Sandals' director of treasury for technology. The framework would also block most wireless signals anyway, he added.
Conversely, power outlets are everywhere around the properties -- even outdoors.
"We wanted to make sure that if we were going to charge [guests for Wi-Fi] that we had to have proper coverage in all the rooms," Stewart said. "With the lack of cabling, we knew we needed a mesh solution."
Stewart chose Ruckus Wireless, whose wireless mesh nodes are enabled with beam-forming and beam-steering technology, which maximizes signal strength by minimizing the number of hops. Since last year, Sandals Resorts has deployed more than 400 wireless access points (APs) -- between 10% and 25% of them mesh nodes, depending on the location.
"You don't want to roll out a network where everything is mesh and one of them is [wired] … because every time you link another jump, you cut the bandwidth in half and it just becomes impractical," he said. "On most of the networks at the hotels, we only have one or two mesh jumps."
Lou Schmaus, MIS director of ADI Logistics, a 160,000-square foot, third-party logistics warehouse in Edison, N.J., is also a Ruckus customer. He had been using a few consumer-grade wireless routers to get some basic Wi-Fi access for a handful of portable work stations near the main office.
But then a customer wanted to set up 20 computers that could scan and track the items it housed at the warehouse. The spot the customer chose was about 400 feet away from the main office, and out of wireless range.
"We didn't want to have to run cabling from one end of the building to the other," said Shmaus, who set up three wired APs as far as he could and three mesh nodes at the end of the building where the computers were. The move saved the company more than $10,000, he said.
"We get an excellent signal. It's no different than sitting next to the wireless signal in the main office, and we saved a ton of money," Shmaus said. "All of our mesh units only have a single hop. We've had a couple instances where somebody's kicked out a power plug on one of the units, and the mesh automatically connected to another mesh unit."
Other players in the mesh market include Motorola, whose Enterprise Mobility Solutions division has attempted to answer mesh's limitations by increasing the capacity of the nodes. Its most recent outdoor node aggregates data speeds from radios in its three-by-three multiple input, multiple output antennae, in addition to broadcasting transmission vertically and horizontally for a greater range.
"Motorola looks at this very specifically as the capacity in the network is … the capacity of a node-to-node connection," said Chip Yager, director of operations for mesh networks at Motorola. "The more capacity we can make [between nodes], the more applications and the more users and the more bandwidth there is to do the next thing."
Let us know what you think about the story; email: Jessica Scarpati, News Writer
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