Chapter Summary
Wireless networks include components that make mobile and portable application possible. Users are end points of the wireless network and utilize computer devices designed for a particular application. Wireless NICs and base stations are key components that communicate over the air medium. To provide roaming throughout a facility or city, a distribution system such as Ethernet interconnects base stations and interfaces users to servers and applications located on the wired network.
The seven-layer OSI reference model depicts functions necessary for a network, but wireless networks implement only functions defined by the bottom two layers—the physical and data link layer. These functions include medium access, error control, and formation of radio and light signals for propagation through the medium. When deploying wireless networks, however, it's important to ensure that protocols operating at higher layers have features that counter impairments found in wireless networks.