Open Communication
by Louis E. Frenzel
The Latest in Networking and Wireless Technologies
Open Communication
ETHERNET — PART 2: Wireless LANs
In the last Open Communications
column, I covered wired
Ethernet. This is the universe's
most popular local area network
(LAN) whose physical layer (PHY) or
transmission medium is usually category 5 or 6 (CAT5/6) twisted pair or
fiber optic cable. Now, a wireless version of Ethernet is quickly expanding
Ethernet LANs and creating a whole
new way to access the Internet from
almost anywhere.
Known by its IEEE (Institute of
Electrical and Electronic Engineers)
standard number 802.11, wireless
Ethernet is extending the LAN outside
of the enterprise and small businesses
into homes, airports, restaurants,
hotels, and many other public areas.
Like the cell phone, wireless Ethernet
lets you stay in touch with your Email
while you are on-the-go via your laptop
or PDA. Wireless Ethernet is certainly
revolutionary rather than evolutionary
in the development of Ethernet.
Background
Radio-based LANs first showed
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up in the mid-1980s but they were
large, expensive, and had low data
rates. While a few companies adopted them, it has not been until the late
1990s that wireless local area networks (WLANs) really took off in the
marketplace. What made the difference was all of the work put in by
companies to form a universal standard that could be used world wide.
After years of work, the IEEE
WLAN standard 802.11 was ratified
in 1997. This gave us 1 and 2 Mbps
(millions of bits per second) connectivity. Then in 1999, a revised standard 802.11b was formalized. That
standard — which offers an 11 Mbps
data rate — made wireless Ethernet
instantly acceptable. Today, WLANs
are the fastest growing segment of
the electronics industry.
Furthermore, even newer, faster versions have been developed,
approved, and converted into rapidly
selling products.
Another reason for the growth
and success of 802.11 WLANs was
the establishment of the Wi-Fi
Alliance. Wi-Fi, meaning wireless
fidelity, is the trade name for
the organization of equipment, chip, and software
companies making WLAN
products. While the existence of a standard helps
ensure that equipment made
by one company works with
that of another, it is no guarantee. As it turned out early
on, there were enough interoperability glitches and
issues to make companies
get together and solve these
problems.
The Alliance was set up to provide testing and certification of
WLAN products to ensure interoperability. Companies submit their products to Wi-Fi for testing and, if they
meet the rigid specifications, they are
blessed with the Wi-Fi label. The Wi-Fi effort removed the last doubt
about the interoperability of WLAN
products from one vendor to another.
The market blossomed as a result.
The acceptance of 802.11 products has increased sales exponentially over the past several years thereby
decreasing prices and encouraging
even greater adoption. This is truly
one of the most successful wireless
products ever, other than the cell
phone. If you don't know about or
use this technology, it’s time to get
on board, as surely it will affect you
or provide you with a communications option that can benefit your life.
Benefits
FIGURE 1. Typical WLAN plug-in adapter for
laptops. Courtesy SMC Networks.
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What makes WLANs so popular?
It's simple. People love their freedom
and mobility. Just as most of us have
become addicted to our cell phones,
so have many become addicted to
Email and Internet access. It is a
great benefit to be able to access
your Email and the Internet from anywhere with your laptop. It lets those
in companies move from office to
office with their PC and it allows you
to take your laptop to meetings in
conference rooms and other offices
without losing touch.
In addition, you can now use
your laptop from an airport, restau-
FEBRUARY 2004
