At a renovated textile warehouse near Boston's Fort Point Channel, where 50 employees of Ember Corp. are moving this month from cramped quarters next door, young engineers are busy lining the walls with 600 wireless sensor nodes -- each containing a low-powered radio frequency microchip mounted on a printed circuit board.
Technologists at Ember and a batch of other start-ups on both coasts believe such ''mesh networks" with their ''radios" -- tiny chips just seven millimeters long and seven millimeters wide -- will be the next big thing in the high-tech world, wirelessly ferrying data between hundreds of sensors throughout homes, factories, and office buildings.
''The technology is taking off right now," said Venkat Bahl, vice president of marketing at Ember. Recent developments at the company appear to prove his point: Ember just closed a $25 million venture financing round, has doubled its workforce in the past six months, is nearly tripling its space, and is installing its network of nodes as a testbed for its own technology and its customers' applications. ''We're seeing people starting to put real money into the technology," Bahl added.
Similar signs of growth can be seen at other area companies targeting wireless sensor markets. Software maker Millennial Net Inc. pulled in $15 million in financing in May, and in July moved from Cambridge into larger space in Burlington. Sensicast Systems Inc. of Needham struck an alliance with GE Global Research and Rensselaer Polytechnic Institute in August to develop wireless sensor technology under a grant from the Department of Energy. ''Device-to-device networking is going to be a huge opportunity, and the Boston area has the chance to dominate," said Paul Sereiko, president of Sensicast, citing research being done at Massachusetts Institute of Technology and Boston University.
In an effort to gauge the business impact of the emerging technology niche, a study released last week by the San Diego research firm ON World Inc. estimated the wireless sensor industry would generate revenue of $140 million this year and $7 billion by the end of the decade.
Mereca Hatler, the firm's research director, said the key is the low power of the radio frequency chips and the short range of their signals, between 300 and 700 feet. Those features will enable companies to install hundreds of sensors at relatively low price for a myriad of applications, she said. Some will replace existing wired networks that control mechanical systems, while others will be used for entirely new applications, ranging from remote monitoring of home appliances to electronic sniffing for chemical and biological agents.
The ultimate vision, hatched in university laboratories at MIT and Berkeley in the 1990s, is an ''Internet of things" linking tens of thousands of sensor mesh networks. They'll monitor the cargo in shipping containers, the air ducts in hotels, the fish in refrigerated trucks, and the lighting and heating in homes and industrial plants.
But the nascent sensor industry faces a number of obstacles, including the need for a networking standard that can encompass its diverse applications, competition from other wireless standards, security jitters over the transmitting of corporate data, and some of the same privacy concerns that have dogged other emerging technologies.
''We're seeing a convergence of technologies that will let corporations and governments keep track of every physical item on earth at every moment," warned Katherine Albrecht, a New Hampshire privacy advocate who has led a national consumer campaign against radio frequency identification of retail items and is turning her attention to mesh networking. ''We're trying to put a finger in the dike."
Advocates of the new technology are working to address the privacy and security concerns through a proposed wireless networking standard, called ZigBee, or 802.15.4 in engineering parlance. Ember's new chairman, Bob Metcalfe, creator of the ethernet networking standard, is among the industry leaders evangelizing the new standard through the ZigBee Alliance. But even before the new standard is ratified, some companies have begun selling prestandard products. And a separate ecosystem of companies, including giants like Intel Corp. and Cisco Systems Inc., is promoting a longer-range wireless standard, called WiMax, which is geared toward cellphones, laptop computers, and handheld devices but could potentially impinge on ZigBee.
''The technologies are now on parallel competitive tracks," said Navi Radjou, vice president for enterprise applications at Forrester Research, the Cambridge research firm. ''The two standards will coexist for a while. But at some point, by the end of the decade, the applications might merge. Then application developers will have to choose."
Even some wireless sensor companies that are ostensibly backing ZigBee harbor doubts about how widely it will be embraced. ''It's early, it's unproven, and it's not ready to be used by customers yet," said Andy May, president and chief executive of Millennial Net, which is marketing mesh networking software before the proposed standard is completed. ''It's unknown whether ZigBee will be widely adopted. While we're waiting, we have our own product, and it works terrific. And it's being embedded into customers' systems."
In the meantime, executives at Ember, whose financial backers include Metcalfe and Microsoft Corp. cofounder Paul Allen, say they already have signed up 80 customers for their ''ZigBee-ready" technology and have set up an ''Ember University" at their new headquarters to train customers in wireless sensor applications.
The goal of the wireless sensor industry is to reduce the cost of a node, including microchip and software, from between $150 and $200 today to $10 or less by 2010. Because the industry is still in its infancy, it's not yet clear whether the players will evolve as competitors, suppliers, partners, or customers of one another, or some combination of each. ''The pioneers of embryonic markets have to do everything for their customers until an ecosystem develops where they can each focus on their core competency," said Sereiko of Sensicast.
Nor is it clear whether the cluster of start-ups in the Boston area could take root as a significant industry here. Another cluster in Silicon Valley, including Crossbow Technology Inc. and Dust Networks, uses technology from the ''Smart Dust" program at the University of California at Berkeley. And some analysts predict whichever start-ups emerge as winners will be snapped up by networking or technology conglomerates.
But for now, the mesh network entrepreneurs are focused on their own growth -- and the growth of their market. ''Our goal is to create a company that is the Intel or Microsoft of its space," maintained Jeff Grammer, the Ember president and chief executive.
Robert Weisman can be reached at email@example.com.