A method for the fabrication of nonpolar indium gallium nitride films as well as nonpolar InGaN-containing device structures using metalorganic chemical vapor deposition. A signal driver adjusts the second timing for the video signal supplied to respective signal lines to correct a backward shift of the third timing due to a transmission delay along a scanning line of the control signal output from the control scanner. The infrared sensor may detect an intensity of infrared light. The proximal tube shaft includes a substantially straight or a slightly curved portion. The network monitoring system enables users to zoom in on high-level, coarse time scale network performance data to one or more lower levels of network performance data at finer time scales.