4.7 Wireless Local Area Network

Currently, the use of WLAN is rising. There are several reasons for this:

• Mobility—the user is not limited by the cable and socket.
• Fast and easy setup.
• Lower overall cost of building the network (no need to build expensive cable distribution infrastructure).
• Extendibility by choosing a suitable antenna and setting its polarization appropriately. In this way both the capacity and territory covered can be extended.
• Roaming is an important WLAN feature. If roaming is set, mobile stations can freely move within an area covered by the signal of access points if these access points are interconnected, for example, by the backbone network. Mobile stations log onto the access point providing the best signal-noise ratio (SNR). Should this ratio decrease below the limit set or should the signal disappear completely, the mobile station switches into the promiscuous mode or looks for another access point with the best signal-noise ratio. Roaming does not disturb...