See Them in September: WiMAX and ADSL 2+

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The middle of August can strike a vaguely melancholy chord: Two weeks left of summer. (Sigh.)

Sometimes, the only way to snap out of it is to freak yourself out with what’s looming, both ahead and off to the side.

Two looming competitive threads wove through the news this summer, and thus will serve as this week’s “translatables.”

One bears a resemblance to both friend and foe, depending on whose toolbox it’s in.

The other is unabashedly “foe.”

The friend/foe is a new-ish flavor of wireless called “WiMax.” The foe is ADSL 2+, a technology weapon that telcos are readying to aim at video providers.


WiMax first. In short, WiMax is Wi-Fi (wireless fidelity) on amphetamines: Way faster, way more reach. It blasts bits at speeds of up to 70 Megabits per second, shared amongst users. (Heavy on the “up to,” some caution.) As for reach, WiMax signals can move a theoretical 31 miles, although most say five to 10 miles is more likely.

In short, what Wi-Fi is for your home or office, WiMax is for your subdivision or office park.

Perhaps not surprisingly, WiMax is wreathed in boom-grade hype. Proponents frequently tag it as “disruptive,” as in, to cable and DSL broadband offerings. They use tantalizing phrases, like “nomadic portability,” to express why people will go for it.

In the Wi-Max engine room, the technology goes by a more stultified name: The “Air Interface for Fixed Broadband Access Wireless Systems.” (Hook me up.) It moves under an IEEE specification, known as 802.16. (Wi-Fi moves under “the 802.11s,” to include their suffixes – “a,” “b,” and “g.”)

In one version (802.16e), WiMax works without the need for “line of sight” between the subscriber device (i.e., laptop) and the antenna. It’s achievable because its creators placed spectral boundaries between 2 and 11 Gigahertz. That spectrum, by the way, is both licensed and unlicensed.


Like Wi-Fi, WiMax has its own industrial support group — — and a noteworthy list of big proponents, like Intel Corp., Motorola Inc., Qwest, Communications International Inc., EarthLink Inc. and Alcatel.

Intel is perhaps the most predictive about WiMax. At various wireless gatherings this year, executives talked specifics about the phase-in of the technology. By next March, they say, expect to see exterior-mount antennas in the $350 range. By this time next year, they foresee a sub-$200 indoor antenna that people can install themselves.

The early applicability of WiMax will likely be as a traffic backhauler for Wi-Fi “hot spots,” observers say. But, naturally, the chips Intel makes for PCs and laptops will do WiMax, too. By 2006, Intel says, expect to see slide-in WiMax cards for around $150.

Most people who watch WiMax say the service will likely come from “wireless ISPs,” which go by the spoken acronym “WISPs.” Some cities are already installing the equipment themselves, as a way to provide low-cost, city-wide broadband access. (Yikes.)

Others, including digital subscriber line provider Covad Communications Inc., are eyeing WiMax as a sort of “fill in technology,” to touch hard-to-reach areas.

WiMax as a fill-in technology is a workable cable angle, too: It’s entirely plausible to imagine WiMax as an answer for rural markets, or city pockets where dropping lines is tricky or prohibitively expensive.

Cable technologists are increasingly vocal about their interest in wireless and “mobility,” as an important element for competitive differentiation. Right now, their comments tend to fall into the “we better do something” category, rather than the “here’s the plan” category.


Then there’s ADSL 2+ — the unabashed foe. It’s different than today’s DSL in that it ascends slightly higher, spectrally — to the 2.2 MHz range, from 1.1 MHz. The extra bandwidth gives it headroom for faster speeds.

How much speed depends on distance. In DSL networks, there’s a direct correlation between “loop lengths” — the distance, measured in feet, between DSL customers and DSL equipment. The closer, the faster, and visa versa. In best case scenarios, meaning short loop lengths, the theoretical max for DSL 2+ is a healthy 24 Mbps, downstream (toward customers).

Roughly half of the U.S. installed base of telco wires to homes, however, can be categorized as loop lengths of around 12,000 feet, observers say. Under those conditions, DSL 2+ can move bits to homes at about 6 Mbps. That’s plenty enough for video, not including advanced video compression.


Equipment makers are already beginning to make set-tops for DSL+, which also go by “IP/DSL” set-tops. They’re estimated to run in the $185 range, per box, using existing MPEG-2 technology. Units with advanced compression are on the way. Both versions have innards that make telcos capable of offering HDTV, VOD and interactivity.

A look under the hood shows that chip makers are already well underway with single-chip DSL 2+ implementations, too. Broadcom Corp., the cable industry’s largest chip supplier for cable modems and set-tops, makes them. They’re priced at around $15, for a single chip, at 10,000-piece order levels.

And if you really want to freak yourself out of the summer doldrums, try envisioning the foe-view of WiMax, with DSL 2+ as a co-conspirator. That Broadcom DSL 2+ chip comes with built-in Wi-Fi capabilities. WiMax can’t be all that far off. That means data and video services, delivered citywide, with or without wires — by someone other than you.

Kind of gives “back to school” a whole new meaning, eh?

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