Network monitoring devices and network monitoring techniques are disclosed and use inferential statistical approaches to determine one or more Key Performance Indicators, particularly for Circuit Switched FallBack scenarios. An inlet valve and an outlet valve are provided, and a diaphragm arrangement is driven by the same motor as the impeller to provide priming. Alternatively, the cable management channel may be rotated on the mounting bracket to move the cable management channel away from the area of the equipment enclosure normally covered by the cable management channel. Since the number of the impact of the hammer due to trouble in fastening operation is smaller than that due to the screw or the bolt is fastened completely, it is possible to distinguish the increase of the torque in the former case from the increase of the torque in the latter case. A module within the server intercepts the connection request and redirects it to the second network intermediary.