1. A system comprising: a controller to be disposed at a site and including a communication device capable of initiating an 802.11 based network to communicate with a mobile device; said controller including a proximity detection module configured to receive a location information from the mobile device; and said controller configured to: detect the mobile device establishing or losing an 802.11 based connection to said 802.11 based network; alter an operating condition at the site in response to detecting the mobile device establishing said 802.11 based connection; enable the proximity detection module in response to detecting the mobile device losing said 802.11 based connection; alter the operating condition at the site in response to the received location information; and disable said proximity detection module in response to detecting the mobile device re-establishing said 802.11 based connection.