The object of disclosing the novel art consists in providing a highly reliable mesa-structured avalanche photo-diode using a novel structure capable of keeping the dark current low, and a fabrication method thereof. The evaporative cooling system is in thermal contact with the fuel cell and with the thermal deicing device in order to conduct heat from the fuel cell to the thermal deicing device. The first receptacle is capable of receiving an add lens for providing an add power. The jam signal indicates a second station is to transmit data. This protection switching data is inserted within the path overhead for the data traffic so that it can be communicated to all of the network elements that require their switch fabrics reconfigured to establish the protection path of communications.