Tropos: Supplier of Metro Wi-Fi

Tropos: Supplier of Metro Wi-Fi

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Written By Eric Sandler

By Eric Griffith

May 21, 2003

As of today, the company now known as Tropos Networks is unveiling what it calls its ‘Cellular Wi-Fi System,’ which the company says will reduce cost by using a city-wide mesh network to replace backhaul. The system already powers hot zones like that found in Half Moon Bay, Calif.

The troposphere is the lowest level of the earth’s atmosphere. It’s where all the weather takes place and where we surface dwellers live. Bert Williams, vice president of marketing at Tropos Networks of San Mateo, Calif. says his company took its new name from troposphere because it “is ubiquitous and ground level, just like us.” And he concedes anything was better than the place holder name they’d been using (FHP Wireless) since being founded in 2000.

Just how ubiquitous and at what level Tropos and its products might be are arguable, but the company hopes to make a splash with what it calls a “cellular Wi-Fi system.” Even if it’s just one city at a time.

Today the company — trivia buff’s will want to note that CEO David Hanna, is the son of William Hanna of Hanna-Barbera cartoon fame — took official wraps off the system, a mesh network specifically for metropolitan areas that would eliminate extra backhaul needs. Each access point connect to another until signals get back to a unit hardwired to the Internet connection. Williams says the costs incurred by just adding more and more access points, each of which must connect to the Internet whether by a DSL line or T1 line, are just too high.

Tropos’s customers, he says, are probably the same as those Mesh Networks and Vivato are after, but says Tropos has a slightly different approach from Mesh’s self-healing networks or Vivato’s single long-range beamed signal from a switch.

The key ingredient of its products is the Tropos Sphere network operating system (NOS), a Layer 3 implementation running on what Williams calls “Wi-Fi cells,” the access point hardware connecting users and the other access points. The cells use what’s called “predictive path optimization” — Williams calls that technology Tropos’s “key intellectual property” — to optimize the traffic traveling to and from a wireless client, through each cell, and back to the gateway cell with the wired connection to the Internet. Each cell can automatically discover what cells are closest to it and what path is the shortest for traffic to take. Add or remove a cell, and the path is instantly reconfigured, like any good self-healing mesh network should. Capacity on the network can be upgraded as needed by adding backhaul to select gateway cells. Administrators can control the system using Tropos Control network management system.

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The Wi-Fi cells are made with off the shelf components, including the 802.11 chips and using an embedded version of Linux. The hardware, in both indoor and outdoor models, is easily upgradeable by the company because of this — though not by end users. The cell boxes are usually mounted in such as way that they’re difficult, if not impossible, to access. Power hookups for the cells can be done direct to the photocells that power many traffic lights (assuming that’s where the outdoor model is mounted) or direct wiring.

Upgrades to software are part of the 24×7 support Tropos offers to customers.

Tropos is not in the business of running the network. The cellular Wi-Fi system is for sale to WISPs looking to provide metro-area-wide “hot zones” with a cloud of 802.11 coverage for all users inside that area. One company, , already has setup service throughout the tourist town of Half Moon Bay, Calif. Eight Tropos Wi-Fi cells are hooked up there, with only two of them connected to T1s for backhaul.

“If you go into downtown with a laptop,” says Williams, “you fire up a browser, you’ll see the splash screen inviting you to purchase time on the CoastWave service from” Introductory roaming fees go from 15 minutes for $2.95 to three hours for $14.95 when using the downtown hotzone, but offers unlimited downtown access to its regular customers for $10.00 per month on top of the regular charges for wireless access in a home or business.

Tropos equipment is also live in Boulder City, Nev., and the company’s home town of San Mateo, specifically to serve public safety departments.

Williams sees that opportunities as being perhaps the biggest Tropos has — in the short term, at least. Police running laptops in their cars these days are limited to CDPD , Motorola Datatac or other limited services that only are good for text messaging or dispatch. “But with high bandwidth they could download and upload images of suspects, finger prints, and get stuff from the Amber Alert system. A cop on the beat might be the last person to see a picture of a missing child… not anymore,” says Williams. He says a Tropos-based hotzone could work not just for police but also everything from public works to the parks and recreation, and back to the consumer end-users who could get it as a public utility. Each department can use the same network, but run their own servers to serve users.

The price of a Tropos hotzone setup would depend on the layout of the area and what is needed for coverage. Williams estimates between $20,000 and $50,000 per city. Tropos can serve as project managers for an installation, even doing site surveys, but they’ll subcontract out installation to system integrators and recommend partners for management/monitoring. Tropos does provide 24×7 tech support for customers.

Ready to get your own Wireless ISP service off the ground? Join us at the 802.11 Planet Conference & Expo, June 25 – 27, 2003 at the World Trade Center Boston in Boston, MA. Get started with our two part panel entitled Practicum: Building a Successful Wireless ISP.

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