The Kit contains an Active Fail-Open Optical Bypass Switch (Optical Bypass Switch) and all the connecting components to connect the switch to the monitoring ports of the Sensor. Additional cables may be required to connect the Optical Bypass Switch to your other network devices such as, routers or switches. With the Optical Bypass Switch in place, the switch receives power from the dual power adapters (for power redundancy, use two independent power sources). When the Sensor is operating, the switch is "On" and routes all traffic directly through the Sensor. When the Sensor fails, the switch automatically shifts to a bypass state: in-line traffic continues to flow through the network link, but is no longer routed through the Sensor. Once the Sensor resumes normal operation, the switch returns to the "On" state, again enabling in-line monitoring. During normal Sensor in-line fail-open operation, the Optical Bypass Switch sends a heartbeat signal (1 every second) to the monitoring port pair. If the Optical Bypass Switch does not receive 3 heart beat signals within its programmed interval, the Optical Bypass Switch removes the Sensor's monitoring port pair from the data path, and moves the Sensor into the bypass mode, providing continuous data flow.