802.11 Security

Inherent Insecurity

Data in conventional networks travels across wired mediums. Coaxial cable, twisted pairs of copper wire, and strands of fiber optics have been the foundation for networks for many years. In order to view, interrupt, or manipulate the data being transmitted, the wires or switching equipment have to be physically accessed or compromised.

Tip

An attacker does not need to physically tap into wired communication in order to eavesdrop on it. Wired communication that uses electrons to transmit data (such as phone calls and 10BaseT Ethernet) radiates small amounts of electromagnetic energy. With highly sophisticated equipment, an attacker can reconstruct the original data stream from the radiated energy. The skill required to pull off this attack as well as the relative proximity the attack requires, however, makes it highly unlikely.

Restrictions on physical access to network cables have been a cornerstone of information security. While physical protection of cables obviously does not solve all the network security problems, it helps mitigate the risk of certain man-in-the-middle (MITM) attacks. Wires are relatively easy to keep physically secure. Placing wires inside of a controlled space such as a data center keeps the physical layer secure from the majority of attackers.

When using radio frequency (RF) communication channels such as a WLAN, users lose the fundamental physical security given to them by wires. WLANs use high frequency radio waves to transmit ...