The status of a video call is displayed in a simplified and intuitive graphical user interface that presents status information of individual video devices of the video call with graphical or color indications with a gauge metaphor, such as a vertically or horizontally aligned bar of icons. The set of preconditions establish dependencies between tasks in the storage area network. A first copy of the test signal is transmitted via a reference path of known characteristics and with minimal impairments. The measurement or estimation of the acoustical output of the loudspeaker may be used to realize a noise dosimeter or as a means to determine the maximum allowable output limit of the electronic audio device. The constituent signals are amplified equally or substantially equally, and then summed to construct an amplified version of the original time-varying envelope signal. The measured traffic volume may be reported to the upper layer when the volume is out of a given range or a timer set to a given period has expired.