Enabling Encryption Security

The problem with most wireless LANs is that security is often considered
optional and is turned off by default on every system. The entire
premise of a wireless network is a wonderful convenience; however it
has no security out of the box. It becomes your responsibility to determine
how best to enable security so that people don’t attempt to access
your network without your knowledge.
Why don’t most people enable security by choice? This is an important
question that has a good answer. An 802.11b network, for example,
with the best possible range and signal, has a maximum throughput of
11 Mpbs. While that speed may have been considered “as good as it
gets” five to ten years ago, today people are finding wired 100 Mpbs
LANs too congested for transferring files and other large objects over
the network.
When you enable security on a wireless device, there is a certain
degree of overhead that reduces the overall speed of your connection
because it is effectively encrypting your network traffic on one end and
decrypting it on another end. While the computer processes this information
quite quickly, it cuts into your overall speed.
If you decide to enable a much stronger level of encryption in the 128-
bit range, then you will have to deal with an even greater consumption
of bandwidth involved when encrypting and decrypting your traffic. A
greater portion of the radio frequency spectrum transmission is consumed
with encrypted packets and this reduces your speed accordingly.
The 802.11b standard enables security through both authentication
and encryption. Authentication is either a shared key or an open system.
When the network router receives information, it may permit a
request to be authenticated on that one station or on all the stations on
Wireless LAN Security Factors 35
its list. With a shared key, only those stations that have that same
encrypted key can permit authenticated users to access that portion of
the wireless network.