As with any hot market, point-to-point wireless is bait for the pathologically opportunistic. Scrambling for market share, they plunge headlong into uncharted waters dragging customers to the murky depths. Those standing on the shores are left to ford a sea of marketing hype that obscures the pitfalls and dumbs down the knowledge base.

You can't even rely on industry pillars to be careful with their facts. Examples are everywhere. For instance, the Web based "Learning Center" of a Fortune 500 telco lists microwave as sometimes achieving data rates from fractional T1 to 10 megabits. Antenna sizes are said to range from 30 cm to a meter. Actually, microwave can push a gigabit of bandwidth and dish size can be anywhere from one to twelve feet. Am I splitting hairs?

In this atmosphere - so often termed "anarchy", trust can't be a matter of faith. To get in on the wireless opportunity without getting shafted, you need to know a few basic and incontrovertible facts concerning the difference between licensed and license-free wireless. A successful outcome depends on making the right choice between them.

FACT #1
There is a difference between licensed microwave and unlicensed wireless.  It's reckless for anyone to say otherwise. For starters, an unlicensed link can be put in for a few thousand dollars, but a typical licensed set-up starts at $30,000.

If license-free wireless is "practically the same," then what accounts for the huge cost difference and why do educated buyers go for it to the tune of billions of dollars a year? I would submit that they know something.

FACT #2
Licensed microwave is "carrier-class" and unlicensed is not. Forget that vendors are slapping "carrier-class" stickers on everything. Using the term in such a fast and loose way blurs key distinctions that tell whether a product is suitable for mission critical applications. Simply put, a product is "carrier-class" if it meets the exacting standards of a carrier (e.g., Verizon, AT&T, etc.) for its own network infrastructure.

Licensed microwave is the unanimous choice of leading telcos worldwide and that's because nothing else matches the bandwidth and interference protection.

Central office and co-location rooftops are jam packed with heavy, drum-shaped licensed microwave dishes, yet the last time I stood on the roof of 60 Hudson (NYC), I didn't spot a single license-free antenna.

FACT #3
Licensed microwave is inherently interference-free; unlicensed is not. Licensed radios have to meet exacting FCC rules for transmit power, channel spacing, bandwidth utilization, receiver sensitivity, antenna size and even the width of the radio beam. But that's not all. The actual microwave path must be licensed before the radios can be turned on. All this promotes efficiency of the licensed radio spectrum so that a multitude of users can enjoy their own slice of radio heaven.

By contrast, license-free radios can go from box to rooftop in a matter of hours.  Many of these radios operate in the same frequency bands shared by a geometrically expanding number of wireless consumer devices.  For some there will be no effect. For others it's a ticking time bomb.