Reach Wi-Fi

Reach
Due to reach requirements for wireless LAN applications, power consumption is fairly high compared to some other low-bandwidth standards. Especially Zigbee and Bluetooth supporting wireless PAN applications refer to much lesser propagation range of
Mobility
Speed vs. Mobility of wireless systems: Wi-Fi, HSPA, UMTS,GSM
Because of the very limited practical range of Wi-Fi, mobile use is essentially confined to such applications as inventory taking machines in warehouses or retail spaces, barcode reading devices at check-out stands or receiving / shipping stations. Mobile use of Wi-Fi over wider ranges is limited to move, use, move, as for instance in an automobile moving from one hotspot to another. Other wireless technologies are more suitable as illustrated in the graphic.
Threats to security


The most common wireless encryption standard, Wired Equivalent Privacy or WEP, has been shown to be easily breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2), which began shipping in 2003, aims to solve this problem and is now available on most products. Wi-Fi Access Points typically default to an "open" (encryption-free) mode. Novice users benefit from a zero-configuration device that works out of the box, but this default is without any wireless security enabled, providing open wireless access to their LAN. To turn security on requires the user to configure the device, usually via a software graphical user interface (GUI). Wi-Fi networks that are open (unencrypted) can be monitored and used to read and copy data (including personal information) transmitted over the network, unless another security method is used to secure the data, such as a VPN or a secure web page. (See HTTPS/Secure Socket Layer.)
Population
Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel on initial startup, contributing to congestion on certain channels. To change the channel of operation for an access point requires the user to configure the device. Yet, this default use of channels 1, 6 and 11 gives better performance than "advanced" users choosing channels 2, 5, 7 and 9 as "unused, free".