Wireless LANs introduce several deployment and usability factors that should be considered. An Ethernet system generally has its electrical current traveling neatly bounded inside a wire. As the elements that make up a WLAN depend heavily on communication via RF through the air, the fact that a WLAN is an unbounded medium introduces many factors. The performance and reliability of a wireless LAN is dependent on atmospheric conditions, physical obstructions, other WLANs, RF interference, RF propagation characteristics and the basic laws of physics. The use of a WLAN is therefore generally not as reliable or as fast as a wired system, however recent developments in the communications standards that actually use some of these atmospheric anomalies to their advantage have alleviated the problems to a degree. The reliability and performance of a WLAN depends on correct deployment which has all of these conditions taken into account.

Security concerns are also a factor. A WLAN spreads to coverage areas outside that of a controlled wired system, and is much less predictable. For instance, many wireless networks used in the home can be detected from the street outside. A business may inadvertently make their network available to a competitor in an adjacent building. Hence, several security mechanisms exist for IEEE 802.11 technologies. These are covered later.