In recent years, mobile devices have become a large percentage of the end user devices used by workers to perform day-to-day tasks. These devices include Personal Digital Assistants (PDA's) and laptops. When a traveling user visits a satellite facility, or even the corporate office, it isn't very convenient to pull out a network cable, find a network connection under or behind someone's desk, and perform the gymnastics necessary to physically connect to the network. Users taking their laptops to conference rooms or into plant or warehouse environments often find there is insufficient network access. The cost of running network cable to every location where access is required can be rather high. Add to these issues the proliferation of technologies such as wireless voice over IP, radio frequency identification devices, wireless manufacturing devices, etc. and the significant improvements in productivity usually more than make up for the cost of a wireless LAN rollout.
The image to the left shows an Ethernet network with wireless access points. An access point (AP) contains a radio receiver/transmitter to communicate with wireless end user devices. It's typically attached to a network via a network cable. In this example, the AP's are connected to a standard Ethernet switch with TP cable. An end user device must have a wireless NIC installed to connect to an AP. The NIC and the AP must support the same wireless protocols. (See IEEE Wireless Protocol Standards at the end of this article.)
The average real-world range on a business class AP is between 150 and 200 feet. Quality of connectivity and maximum range are affected by environmental conditions. These conditions can include large metallic objects, electromagnetic interference (EMI) produced by machinery, or building materials.
The downside to this is wireless connections create difficult security challenges.