Wireless
LANs:
Small Business & Enterprise Solutions:
Wireless LANs, based on the 802.11b standard
and 2.4GHz transmission, have evolved into a reliable
and convenient technology that can be deployed today in
your office today.
Interoperability is resulting in uses
for wireless LAN equipment that could not have been contemplated
before. For example, if you purchase an 802.11b radio
for your portable computer, you can take it with you when
you travel and make a broadband connection to the Internet
at any AP-equipped (Access Point equipped) hotel, airport,
library, or cybercafé.
Another application is providing clouds
of wireless connectivity within an office. For example,
conference rooms can be equipped so that those attending
meetings can bring their laptops and consult Internet
resources or check e-mail when they need to. Wireless
LANs are also touted for "hot desking," where
roving employees claim desk space on an as-needed basis.
Wireless LANs are also great-either as
a point solution or throughout a campus-when it just isn't
practical to run cable. (Examples of the latter might
be when you're dealing with solid masonry, asbestos, or
a historically important structure.)
A basic wireless network is made up of
two things. First, there's the client radio, usually supplied
in the form of a PC Card with an integrated antenna. Portable
computers are the main target market for these, but they
can also be installed into desktop computers via PCI or
ISA host adapters.
The second component in a network is the
AP (Access Point), which features an Ethernet port plus
a transceiver. The AP acts as the bridge between the wired
and wireless networks. Usually, it performs Network Address
Translation (NAT), DHCP, and other routing functions,
often supporting multiple clients with a single static
IP address.
The range required directly impacts how
many APs you'll need. Figuring out how far a radio signal
will propagate can be as much an art as a science, as
you know if you've ever struggled to receive a station
that your neighbors get with ease.
One thing is certain: 802.11b devices
have a shorter range at 11Mbits/sec than they do at 5.5Mbits/sec,
2Mbits/sec, or 1Mbit/sec. That's why the standard supports
ramping speed down automatically to maintain a connection.
With directional antennae designed for
point-to-point transmission, 802.11b can work for more
than 10 miles at its highest speed. But with the omnidirectional
antenna on a typical AP, range may drop to as little as
100 feet.
In most cases, therefore, you'll need
multiple APs. These are usually deployed in a network
of overlapping cells, in which each adjacent AP may be
assigned a different channel to avoid interfering with
one another. As a user roams from cell to cell, his or
her client driver will seek the strongest possible signal
and maintain connectivity.
Com21net offers Wireless LAN solutions
for your business. We can design, install and train your
personnel on the latest Wireless LAN technologies. We
can provide you with fast and easy access to your wired
LAN and its services from any place in the world with
standard APs (Access Points).
Wireless LANs extends the reach of your
office network to places like hotels, airports, and convention
centers via highly secure VPN connections through the
local ISP network. Mobile business professionals benefit
from fast and wireless access to their company's information.
