Fixed Wireless Business

The ATM WISP

You may think it's impossible to meld ATM reliability with Wi-Fi deployability, but one such network has been running for ten years.

by Alex Goldman ISP-Planet Managing Editor [August 9, 2005]

Allegany County, Maryland is the site of AllCoNet, a wireless network covering 525 square miles using packet radio and microwave technology.

AllCoNet learned about the potential of packet radio technology from Professor Robin Kranz (now Emeritus) of Frostburg State University. Kranz's student, Jeffrey Blank, recalls, "we started out in fixed wireless in 1994, building a system for the schools. Nobody else was doing anything, but my college professor told me to look at packet radio, so I did some gopher searches. Robin Kranz, my professor, had done packet radio for NASA in the sixties. We got early equipment and it worked great. We built a purely Ethernet tree architecture."

The county decided that the network should be run by a private company, and local money created CONXX (pronounced like "connects"), which now owns the technology. Its CTO is Jeffrey Blank. We found out about the company from its latest hire, Ken DiPietro, known to members of the ISP-Wireless discussion list and attendees of the Wi-Fi Planet Conference & Expo as a prolific writer an speaker, and also as co-founder, with his wife Dawn, of a WISP in northeastern Vermont, New-ISP.

The company claims to be one of the oldest customers of Tel Aviv, Israel-based Alvarion, once called BreezeCOM, and is also a longtime customer of LANair.

Building for business
Having proven that the network was possible, CONXX was asked by the county to build a business-capable network to help economic development. Blank explains that this required a different network, AllCoNet2, built on a ring architecture, not a branch architecture.

"They basically asked us to build a replacement LEC, and we settled on a licensed microwave ring architecture," Blank says.

The backbone is served by an OC-12 backbone connecting to a fiber POP built by Broomfield, Colo.-based Level3. David Kartchner, president of CONXX, explains that the company aggregated demand and then approached Level 3 about breaking open a fiber line in their area. Level 3 saw AllCoNet's list of customers and agreed.

(Some of the most interesting stories are those we cannot publish. At an ISP conference five years ago, a young employee of a major fiber network approached us, saying he was trying to pitch a business plan that involved putting POPs at regular intervals throughout the network and urging wireless providers to fill the pipe by connecting to the POPs. As this story shows, that plan could have worked.)

The backbone runs on licensed wireless spectrum in the 11 GHz, 18 GHz, and 23 GHz microwave bands, using equipment such as Stratex Altium products. The edge of AllCoNet is unlicensed spectrum, generally 900 MHz, 2.4 GHz and 5 GHz, using equipment from all the usual suspects, including Alvarion and Tropos.

The middle matters
Kartchner says Blank's team has also built key middleware. "We have a platform that can support QoS to the customer premise, end to end. That allows us to service first responders and other important customers, and also allows us to prioritize traffic types."

"Each customer connected to CONXX's backbone is segregated on their own dedicated VLAN, ensuring the complete security that valuable customers like banks and government entities demand. We can deliver VoIP along with traditional telecom services like T-1s and DS-3s. Our plaform also allows for the integration of Wi-Fi, WiMAX, and mesh, thereby alleviating inherent wireless scalability issues."

Blank is enthusiastic about the middleware. "We can monitor everything from ATM switches to the edge equipment, even the PCs hanging off the edge equipment. We can even monitor the door switches in the generators for our towers."

True wireless. . .
The folks at CONXX are dismissive of deployments that rely too much on legacy copper. "Many wireless network builders are using the telco network for backhaul," says Blank

"However," continues Kartchner, "using T-1s limits bandwidth." They point out that a true mesh network should not require a copper connection for every two or four nodes. With the AllCoNet backbone, a sturdy mesh could, in theory, rely on one or two backhaul connections.

With a better network, applications seems to suggest themselves. Local utilities are using the network for Supervisory Control And Data Acquisition (SCADA) systems.

"We can create very secure networks for banking and government customers," adds Kartchner.

. . . telco architecture
CONXX claims to be able to deliver the security and reliability of an RBOC architecture married to the rapid provisioning and affordable pricing of fixed wireless.

The company has an ATM switch at every tower. In addition, the company added propane-powered generators and battery backups for each tower. That's not cheap. The initial buildout for AllCoNet2 cost $4.7 million, of which $2 million came from the state, $2 million from the federal government, and $700,000 was raised through a local bond issue.

Kartchner says the network provided immediate savings to the school system, and did not need the additional customers to justify its price. "It saves schools and libraries $70,000 per month in telco fees, and we've been running the network for ten years."

Blank explains that the ATM core is never oversubscribed. There's a 1:1 ratio of input to bandwidth, so no packets get lost. However, the Ethernet edge may be oversubscribed. So, in theory, if you had 60 Access Points on a single tower, each trying to pump 10 Mbps into a system capable of 311 Mbps, there would be packet loss or buffering on the Ethernet side.

However, Kartchner points out, the company could just add one—or ten—OC-12-capable point to point backbone radios.

DiPietro says it's a completely different wireless network. "This is disruptive technology that saves a lot of money. It delivers the payback in a short time. It has five nines reliability. This isn't a network built on a shoestring budget held together with duct tape. It functions every day whether it's covered in ice or it's 100 degrees outside. Allegany county is mountainous. It has trees, rivers, and valleys. If it will work here, it will work anywhere. There were good reasons for building here, but it's almost as if they chose the worst environment possible to prove this concept."

Allegany home
In terms of environment, yes, WISPs have complained for years about the challenge for forested hills (see, for example, Up Hill and Down Dale). However, CONXX offered to serve a county suffering from telco neglect, where inferior services were delivered at inflated prices. This, obviously, maximized the savings generated by taking local government off the legacy network.

The company has bid on various other projects around the country, including the Minneapolis RFP (see Glenn Fleishman's take on the Minneapolis RFP here).

In a press release with Marconi [.pdf], Blank says that the support of state and local leaders has been very helpful:

"One of the most interesting things about this project is that it has unanimous support. We have state and federal senators on our side. We have the entire local delegation—the county commissioners, the mayor and city council, and all of the business groups—on our side. It has absolutely been unanimous support."

Unfortunately, CONXX may not receive complete political support in deployments elsewhere.

Nevertheless, the company's unusual, powerful architecture demonstrates just what a true wireless deployment can do, and the people of CONXX are right to be proud of what they've built.

—End