Feel the Power
Nevermind the promises printed on the package. Unless your office happens to be a small computer lab without walls, furniture or people, you won't get anywhere near the transfer speeds or range attributed to 802.11g networking devices.
But who said that's all there is? The latest from Belkin, Linksys, Netgear and others should be hitting store shelves right about now--super-duper adapters that transfer data several times faster and farther than plain old 802.11g devices. Some claim performance beyond that expected from the next-generation 802.11n protocol, though that standard is nowhere near being ratified.
Of course, this is one product category where mileage will vary. It will certainly vary from the ideal, even from one room to another, if your office and network traffic changes at all. In the world of wireless, cubicle partitions and competing electronics, even people affect speeds and feeds.
Still, having played around with six of these prequels under field conditions (the field behind my house), I was impressed. Unless you're transmitting from a lead-lined vault or leave kryptonite lying around, it's a safe bet they would deliver a boost in speed and coverage for your network, too. How noticeable? The only honest answer is: Your mileage will vary. More on that later; first, a word about how they operate.
While vendors might add a little secret sauce, all pre-n adapters use some variation of a common-sense idea that, unfortunately, has been tagged with the usual propellerhead acronym: MIMO (Multiple Input, Multiple Output). It simply means multiple radios send out multiple data beams that get picked up by multiple antennas.
That may similar to the more powerful antennas and repeaters long available to turn mere g adapters into super g adapters (see "Buyer's Guide"). But MIMO devices operate differently. Super g adapters still broadcast along a direct line of sight to one another, hoping to push through obstacles by dint of signal power.
Super-duper adapters send their signals in different directions. They ricochet off walls, furniture and even people to reach blocked access points. That's where parsing algorithms pick the strongest, most consistent signal, changing to another signal if the scene changes moments later. Netgear says its router uses seven different "smart" antennas to sort through more than 100 overlapping broadcast patterns.
It's anticipated that the same technique will be at the heart of the 802.11n protocol, but those specs are still up in the air. The Wi-Fi Alliance, which arbitrates Wi-Fi interoperability, isn't happy about vendors jumping the gun--or labels like "pre-n" and "MIMO." "Manufacturers that put 'pre-n' on the box are irresponsible," says Ken Dulaney, vice president of mobile computing at tech research and consulting firm Gartner Inc. in San Jose, California, voicing the view of both Gartner and the alliance.
Gartner fears market confusion, conflicts among neighbors and inter-brand incompatibility. Prequels of the 11g protocol needed firmware retrofits, "and that protocol was 80 percent there," says Dulaney. "We're only 20 percent of the way to 802.11n, which may not get firmed up until 2007."
Pre-n vendors say their solutions are independent of that spec and won't cause conflicts. If anything, says Vivek Pathela, Netgear's senior director of product marketing and management for residential products, pre-n technology will enhance the bandwidth of 802.11n adapters.
What Is "Fast"?
By how much? I'm not telling--at least, I won't quote absolute results because the very same hardware I played with would perform differently at your site.
These days, vendors also avoid touting ideal speeds. Marketing claims are framed as "eight times" or "800 percent better." And don't expect those multiples when broadcasting to nearby access points--only because 11g adapters do relatively well in close range. It's out on the edge of your network where pre-n adapters reduce dead spots and boost throughput the most. But isn't that where you need the extra oomph?
I got excellent coverage--even when standing in my field. Web
pages snapped in place, and 11g adapters sped up with a MIMO router
on the network (instead of the router falling back as in the
pre-g days). When every connector was MIMO, it was like transferring files between directories on the same PC.
Are they worth the extra dough? Not if you expect faster web browsing and, like so many, share a sub-1Mbps internet connection, says Dulaney. Of course, he adds, you still get extra internal bandwidth. So I say, Why not?
The $50 to $100 price premium on pre-n adapters is only temporary, and you'll quickly get it back in productivity gains anyway. Even if 802.11n is better, you'll have had about 18 months of zippy networking and can take your pre-n adapters home to network that super-duper entertainment center you'll have by then.
But pass on faster and better? Ignore the technological imperative? Nah, that's like pulling on Superman's cape.
Look, Up in the Sky!
These adapters sport multiple antennas--and red Gs on their leotards.
Wireless Pre-N Router: This three-antenna router uses Airgo
Networks' True MIMO to achieve "800 percent wider
coverage" and "600 percent faster speed."
Pre-N Router: $160
Pre-N Notebook Network Card: $100
Wireless-G with SRX: Although using the same Airgo MIMO and three
antennas, SRX devices supposedly deliver "three times"
the range and "eight times" the speed of 11g
Wireless-G Broadband Router: $199
Wireless-G Notebook Adapter: $129
RangeMax: This seven-antenna router uses Video54's BeamFlex to
deliver three to 10 times better speed/range.
RangeMax Router: $150
Mike Hogan is Entrepreneur's technology editor.