Radio waves, being unbounded by cable or wiring, can reach many users who otherwise would be tied to a given desk or location. However, the fact that radio waves transmit information invisibly also allows them to leak information without detection. Anyone who can put a wireless device on the air can passively monitor, or actively invade, a wireless network. Further, wireless systems are prone to interference which can deny users intended services.
Proper antenna selection will do much to keep radio signals confined to the appropriate area. Careful attention to network cablingall wireless networks end up connecting to a wired network at some pointwill also help assure security for your wireless environment. Strictly discouraged are unauthorized or rogue access points. Installing such equipment without the knowledge, and approval of, network administrators can create a tremendous security hazard, even if the installer has only the best of intentions.