The waveforms show the transmission of messages from both input ports to Out1 and ack reception.  

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... passive optical elements are packaged together and the SOAs, the photodetectors, and the control electronics were mounted on a custom designed printed circuit board. The prototype design was used to verify the correct routing of messages with optically encoded addresses and the data integrity of the multi-wavelength messages after the routing. Fig. 4 demonstrates transmission of messages from both input ports to output port #1 and the reception of the ack pulse. In the third slot, messages are sent from both ports, but an ack is received only in port #0, as expected. A power penalty smaller than 0.15 dB was measured for the switching node and 16 wavelengths of 10 Gb/s were routed ...