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« on: May 08, 2010, 08:03:38 PM »
On 12 June, the IEEE Standards Association’s Standards Board formally ratified IEEE 802.11g, an amendment to the wildly popular local-area networking standard known as Wi-Fi. But details of the standard were largely settled last year, enough so that by last January, manufacturers like Linksys Group Inc. and D-Link Systems Inc., both in Irvine, Calif., jumped the gun and shipped to retail stores their home and small-office routers incorporating the standard [see photo, above]. Consumers, in turn, have for some months faced the choice of which 802.11 flavor is best. Anyone walking the aisles of a computer store finds shelves stocked with a bewildering assortment of local networking products, labeled with an alphanumeric soup worthy of a government bureaucracy. IEEE 802.11g is an extension of 802.11b and competes with 802.11a, with which it shares many features. So one obvious question some consumers are asking themselves is whether, given that a has yet to take off in a big way, it will now be superseded by g. Does a still have a real mission? In fact, at an 802.11 conference held in Boston in June, industry analysts and executives were unanimous that within a year or so, virtually all access points will be dual-mode, accommodating both 802.11a and 802.11g. And since the 802.11g standard is backward compatible with b, the so-called access â€hotspots†will bill themselves as â€trimode.†That being the case, consumer devices will be able to use either a or g with impunity, or even remain with b, the version originally dubbed Wi-Fi. The a and g variants specify a bandwidth of 54 MHz, while the b specifies 11 MHz.
Picking through the soup
The general IEEE designation for networking standards is â€802†(IEEE 802.3, for example, is the standard for Ethernet). The â€11†family of standards governs wireless local-area networking, a category that exploded two years ago as companies and tech-savvy homeowners discovered that for a few hundred dollars they could set up Internet access points without wires in conference and living rooms.
The first in the â€11†family to market were a and b. But the first to take off was IEEE 802.11b, which uses an unlicensed portion of the radio spectrum, 2.4 GHz, that is inexpensive to implement. It specifies a networking protocol and an air interface—that is, a way for routers and servers to send out a signal and for devices like laptops and PDAs to find that
signal.
The IEEE 802.11a standard also uses an unlicensed, though different, portion of the spectrum, 5 GHz, but a products are more expensive to manufacture. â€802.11b was a relatively simple hardware upgrade from existing 2.4-GHz [wireless] products, which had been on the market for a couple of years,†says Jim Geier, whose company, Wireless-Nets Ltd. (Yellow Springs, Ohio), provides consulting services to chipset and wireless manufacturers. â€It was taking manufacturers much longer to finalize circuits that would operate in the bands that 802.11a uses.â€
IEEE 802.11a now stands at a crossroads: it offers high data rates, as high as 802.11g does, and more channels—and therefore many more opportunities to avoid interference with other users. Nonetheless, it is incompatible with 11b, presenting the wireless industry with something of a dilemma.
In the final analysis, however, cost—not power usage, range, or data rates—probably will be the determining factor. â€Wireless consumers are primarily price-driven,†says Jupiter Research’s Ask. That might give a decisive edge to Wireless-G, at least at the retail level.
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