Unfortunately, implementing a wireless LAN does not relieve you from any of these usual security tasks. But the good news is that because administrators can either allow or deny access to one or more wireless end points at any given time, WLANs can support an additional layer of authentication management, which occurs before the user even sees a log-on screen.
Furthermore, administrators can configure settings on a WLAN that require end-users to input parameters such as radio domain, sub-channel ID, or frequency-related information. These extra parameters make an enormous difference when securing WLANs.
Of course, most companies are also concerned that hackers may gain network access and sniff the traffic on their systems. Sniffing and other attacks can easily be prevented with encryption, but many network managers do not expend the necessary resources to put this precaution in place. We understand that time, money, and expertise are short, but we urge administrators not to cut corners when it comes to this vital security measure, be your network of the wired or wireless variety.
Most typical WLAN solutions come with support for 64-bit encryption. You can also usually obtain 128-bit encryption as an optional purchase with your WLAN. It should be noted that WLAN encryption only protects data; it is still possible for sniffers to pick up headers in the traffic, although the severity of resulting security breaches are significantly limited by data encryption.
Scrambling airborne data
Perhaps the biggest fear that network administrators have when it comes to implementing a WLAN is that security breaches will occur while network traffic is airborne.
Great news for the fearful: The design of a WLAN's physical layer protects network traffic by using spread-spectrum technology, a security measure introduced by the military some 50 years ago. WLAN solutions that implement spread-spectrum technology resist noise and interference while reducing the threat of unauthorized detection.
When data is transmitted using spread-spectrum technologies, the signal is sent out across a broad range of frequencies at very low power. Of the several ways to implement spread-spectrum technologies, the two most popular and supported methods are direct sequence and frequency hopping.
Direct-sequence spread spectrum combines the sent data signal with a higher bit sequence known as a chipping code or a processing gain. In this scenario, each time a data bit is transmitted, it is interspersed with a specific string of bits.
Frequency-hopping spread spectrum works much the way its name implies. Data is transmitted via a signal that hops from frequency to frequency over time. A hopping code determines which frequencies will be used and in what order.