title: Will the wrong wireless succeed?
by: Scott Bradner
At one time it
looked like there was a roadmap, a confusing one perhaps, but a roadmap
nonetheless. Wireless Internet was going to be everywhere, but you were going
to use different wireless technologies depending on just where you were. This roadmap seems to be being
overtaken by events and a far simpler one may be emerging.
The wireless
roadmap looked something like this:
local communications, say between your cell phone and palmtop, would use
Bluetooth, connections to your office LAN would use 802.11, at home you would
use HomeRF, and when out wandering the world you would use 3G or maybe someday
4G. Come to think of it, I never
did figure out how you or your mobile computing devices would know where you
were so as to know what technology to use. Each technology has been optimized for its particular
role. Bluetooth is low power and
short range - 10 meters or so - but slow - less than a Mbps. 802.11 offers a range of speeds from a
few Mbps to about 50 Mbps at a few hundred meters. HomeRF only needs to cover a house and runs at a few
Mbps. The next generation cell
phone services 3G and 4G will offer a few Mbps at distances of up to a few
kilometers. But maybe optimization is not needed.
Supporters of
most of the technologies in this fuzzy picture might want to consider that
"good enough" rather than optimization may just be taking over.
802.11 is not just for office LANs anymore.
Sure, 802.11 is
showing up in classrooms, hotels, airports and Starbucks. You would expect this
since these environments have basically the same requirements as office LANs.
In addition it should be obvious that for simple Internet access type services
802.11 would also work just fine at home.
But now 802.11 is starting to show up in places that it would not seem
all that well suited for.
802.11 is
starting to show up as competition to cellular-based Internet connectivity.
(e.g., 3G) - as an example see http://www.toaster.net/wireless/aplist.php
for a list of San Francisco area providers. And with the improvements in the power efficiency of future
generations of 802.11 chips Blutooth does not seem so important.
802.11 is far from perfect,
the current versions, 802.11b and 802.11a, have significant security and QoS
issues and having two versions could be a problem. But dual-mode chips that support both versions are now
shipping and the IEEE, the developers of 802.11, are busily working on security
and QoS improvements. (IEEE
documents are now available for free at http://grouper.ieee.org/groups/802/11/)
802.11 is yet another example
of generalization winding up being more important than optimization. In this case there may be rough times
ahead for providers of more ideal solutions such as Bluetooth, HomeRF and, most
dramatically, 3G where the $150 billion spent for frequency licenses may have
been mostly wasted.
disclaimer: Wasting $150
billion is beyond even Harvard's ability and the above is my opinion.