Part 2: A Tenured Expert—continued

In the first part of our series we took a brief look at Jack Unger's fixed wireless broadband tutorial, which began to lay the groundwork for starting a fixed wireless Internet access service. This time out, we get down to the nitty-gritty and ask some tough questions.

by Gerry Blackwell [March 13, 2001]

Last month, we introduced you to the fixed wireless ISP's friend, Jack Unger, CEO of Santa Cruz CA-based Wireless InfoNet Inc., the author of a full-day tutorial on "Deploying License-Free Wireless IP in the Real World."

After learning everything you can about fixed wireless systems, developing a preliminary business plan and deciding which license-free spectrum to use, the next step is to get your hands dirty by actually buying some test equipment and experimenting with it.

This should not be viewed as a critical buying decision that will commit you to anything in the future, Unger stresses. ISPs may have to experiment with various vendors' equipment to find the best products for their specific needs.

"In fact, it's probably prudent to learn a little bit about all of the vendors," he says.

Variable costs of fixed wireless access
Unger flatly refuses to make any vendor recommendations and only reluctantly admits that he has worked most with Lucent WaveLAN equipment. "But I'm not wedded to it," he hastens to add.

The investment in test equipment shouldn't break the bank, but don't plan on skimping, either. Unger estimates that it costs between $5,000 and $10,000 to set up a single fixed wireless Point-of-Presence, otherwise known as a WiPOP.

"That may sound high if you're scanning equipment catalogs," Unger says. "But believe me, when you factor in the costs of transmission lines and uninterrupted power supplies, as well as other peripherals—it adds up."

"Then there are costs for backbone connectivity. Do you bring a T1 to the [tower site] or have a wireless link back to network operations center? There are tower rental costs to consider. But the hardest cost to predict is labor," Unger says. "There is a substantial cost for labor to install, test, and monitor a WiPOP."

Testing, testing ... testing
This is all part of discovering what's involved in becoming a fixed wireless ISP. And as Unger notes, you may decide after completing the trials and tribulations of your WiPOP test experience, that fixed wireless broadband services are not for you or your ISP business.

The test phase is also the time to acquire a practical, hands-on understanding of the basic principles of fixed wireless network design.

Unger says that the first and most important lesson you will learn concerns the placement of your WiPOP, which needs to cover your service area completely and reliably, avoiding interference with other existing and future wireless users.

The mistake a lot of beginners make, Unger says, is to think of yourself as a broadcaster. Finding the highest point in your service area and putting up a few antennas and radios on the tallest tower, hoping to cover it all with one WiPOP, may not be in your best interest.

"You're going to run into interference issues and network expansion issues that could easily be avoided by building several WiPOPs at lower-level locations rather than having the one big 'broadcasting' WiPOP," he says. "This is not always obvious to ISPs just starting out."

However, the one exception to this rule is if you intend to operate a fixed wireless Internet service in a small town or a rural area. There, one WiPOP may suffice.

"But in any kind of urban area," Unger stresses, "I definitely recommend many small WiPOPs be implemented. It's important that you put that in [the article]. It will keep a lot of these companies out of trouble."

Certain predictions
Learning how to install reliable fixed wireless POPs is a major hurdle. How big should the antennas be? How high should they be? How big should the cabling be? How reliable is this link going to be? Your answers will depend on the specifics of local terrain and equipment properties.

"You have to be able to predict link reliability at the time you install," Unger says. "You need to practice doing that—measuring the fade margin [the built-in allowance for fluctuations in signal level] and so on."

Another crucial lesson a new fixed wireless operator will need to learn is how to solve interference issues in the field when they arise.

"You've got to become familiar enough with the technology so that when a reliable link becomes unreliable, you know how to troubleshoot it and return it to reliability," Unger says.

Possible sources of interference include other nearby local or wide area 2.4 GHz network nodes. One common and often unsuspected source is your ISP's own network, either the presence of other WiPOPs too close, or your multipoint links interfering with a point-to-point link back to you network operations center.

Once you're through the initial get-your-feet-wet testing phase, it's time to start thinking in more detail about how fixed wireless network design and buildout issues will impact your existing fixed wireless broadband services.

Humble beginnings
Defining the area of coverage is an important step. Unger suggests ISPs start modestly. Rather than planning to cover all of southern California, for example, plan on hitting the east side of downtown Modesto at first.

Unger believes that virtually every fixed wireless ISP should implement bandwidth conservation and management tools—the ability to throttle the amount of bandwidth an individual customer gets.

"Many times this is not done," Unger notes. "The service provider just runs wide open and gives everyone two megabits or 11 megabits or whatever. They don't realize that they cannot give everybody the full bandwidth without limiting themselves to only a few clients on their wireless POP."

Not all network equipment has bandwidth management capabilities built in. Clearly that should be one criteria in final equipment selection, Unger says.

One big mistake many wireless ISPs make is underestimating how long it will take to get a WiPOP up and running reliably.

"There's a misconception that I can just go out and buy some wireless equipment, find the tallest tower, and put my equipment on it and next week I'll be selling service to satisfied customers. It almost never happens that way," Unger says. "The time needed to build a wireless network and test it—and provide reliable service over it—is typically measured in months, not days or weeks."

Anticipating value
That means your fixed wireless ISP will have to think about managing customer expectations. Chances are, if you're considering implementing a fixed wireless strategy in the first place, there is already pent-up demand for broadband access.

"If you don't manage expectations," Unger warns, "[test customers] will become disenchanted and you'll lose them."

One final piece of advice—always anticipate the unforeseen. Unger's favorite example of the little things that can trip you up is the easy-to-overlook possibility of getting a drop or two of water inside the connector on a transmission line for an antenna. Nothing kills fixed wireless network performance like a drop of water.

"Until you've installed a couple of antennas and water-proofed them successfully," Unger says, "you're not ready to provide reliable service. If the first big rain or snow takes your WiPOP off the air, your customers are not going to be happy."

"And the time needed to deal with these kinds of things simply can't be predicted," Unger says. "You have to allow more time than you think you're going to need because Murphy's law is always in force when it comes to WiPOP setups."

Hmmm. Are you absolutely sure you want to operate a fixed wireless Internet service?

—End

Read Part 1: A Tenured Expert >