A method and system for determining the depth to a water level, particularly depth to a ground water table below Earth’s surface. The laser beam introduced through the transparent substrate 1 repeats a total reflection on the surfaces of the transparent substrate 1 and enters a state in which the laser beam is almost confined in the substrate 1. Filters, based on the analysis of HTTP traffic over a training period, help detect anomalies in outbound HTTP traffic using metrics such as request regularity, bandwidth usage, inter-request delay time, and transaction size. The invention further provides a non-explosive energetic material useful for such reactive armor elements .