"We have a switch technology that resets the footprint economics of wireless LANs for enterprise networks," said Ken Biba, chief executive officer and chairman of Vivato. "With a single switch we can cover an entire enterprise, campus or Wi-Fi hot spot with multiple Wi-Fi transmissions, with centrally managed security over the entire collapsed network." The clients are all standard, 802.11-compliant devices, Biba said.

At the core of Vivato's technology are phased-array antennas. These are a form of smart antenna that use complex algorithms and multiple antenna elements to perform real-time channel estimation and "beam steering" to increase the signal-to-noise ratio (SNR) on a user-by-user basis. The improved SNR is what allows the Vivato solution to increase the WLAN range beyond the typical Wi-Fi network's reach of 300 feet.

The current 802.11 deployment scenario has many additional drawbacks, Biba said, citing the requirement for many access points (APs) and their backhaul. "Also, the microcellular architecture gives overlapping areas of coverage, capacity must be deployed in areas of low activity, and co-channel interference reduces the usable bandwidth," he said. "The installation costs dominate, and the management is a nightmare."

Vivato's centralized switch concept echoes a recent Symbol Technologies announcement. For its Mobius architecture, Symbol also took a low-cost centrally managed 802.11-network route, but did so by stripping the intelligence from the access points and putting it all on the switch. While that reduced the cost of the APs and yielded the required manageability and security, it still required backhauling many APs to that central location.

Vivato's approach eliminates the need for APs altogether. Along with phased-array antennas for increased range, the switch uses space, time and channel multiplexing to maximize capacity. Security features such as 802.1x and Temporal Key Integrity Protocol (TKIP) are provided. The Wi-Fi Alliance last week mandated both of these as essential parts of a Wi-Fi-compliant solution going forward. Another layer of security is added by the tight control of the beam, which not only improves the network's range but also prevents unwanted users from gaining access. For backhaul, "we use the existing infrastructure and can scale to 1 Gbit/second," said Biba.

Threatened domains

The result is a low-capital-expenditure system that can be deployed on campuses, in the enterprise, in public Wi-Fi hot spots or in metropolitan areas. That threatens the domains of companies from Cisco, Proxim, Symbol and Alvarion on the 802.11 side to Arraycomm, Nortel and IPWireless in the 2.5/3G cellular-basestation space and Arraycomm, Navini, NextNet and Beamreach in the fixed-wireless arena.

But the technical and management expertise at Vivato may be up to the task. Biba started in security and networking R&D 30 years ago with Mitre Corp. and was a member of the Advanced Research Projects Agency Transmission Control Protocol (TCP) Working Group that developed the Internet. Phil Belanger, Vivato's vice president of marketing, was a founder of the Wireless Ethernet Compatibility Alliance (predecessor to the Wi-Fi Alliance) and is well-known for his contributions to the 802.11 media-access control layer.

And William "Skip" Crilly, chief technology officer and co-founder of Vivato, was a system architect and engineering team leader for Hewlett-Packard Co.'s wireless communications test instruments, which today are the mainstay of Agilent Technologies' cellular/PCS basestation and cell-phone manufacturing-test product line. Crilly is also a contributor to IEEE standards efforts.

When Vivato closed Series B funding at $20 million in March, it had 18 employees. The employee count has since grown to 80. According to Biba, the company expects to ship product in February 2003.