The VDL4000 is designed for surveillance IP cameras that require long distance transmission. Current IP cameras work with Ethernet UTP Cat6 cable and transfer duplex signals for up to only 100 meters. Our VDL4000 transmits IP duplex signals up to 800 meters away and sends power to the cameras through a coaxial cable. Safety features include powering the cameras only after the local unit and the remote unit are connected correctly, auto shutdown for a short circuit or open circuit, auto shutdown for an overload or signal loss. Also, auto test and reconnection until the problem is solved. It applies to all low and high resolution IP cameras, including PTZ cameras and Infrared cameras with high power consumption.