Cisco® Network Professional's: Advanced Internetworking Guide

19.1. Wireless Fundamentals

Signal transmission using the typical 802.11 specifications works a lot like transmitting does with a basic Ethernet hub: They're both two-way forms of communication and they both use the same frequency to both transmit and receive. The technique is often referred to as half-duplex, as I mentioned in the chapter introduction. Wireless LANs (WLANs) use radio frequencies (RFs) that are radiated into the air from an antenna that creates radio waves. These waves can be absorbed, refracted, or reflected by walls, water, and metal surfaces, resulting in low signal strength. So because of this innate vulnerability to surrounding environmental factors, it's pretty apparent that wireless will never offer us the same robustness ...