Characterization of Burst-Mode Links for Optical Circuit Switching

The performance of an optically circuit-switched network depends on the transient locking characteristics of the transceiver as a function of the received power before and after a switching event. These characteristics are not specified in current transceiver standards. Here, we present a novel characterization method to assess the transient locking characteristics of transceivers when used in an optical circuit-switched network. The method uses custom hardware code implemented on a high-performance FPGA. This code samples the bit error rate in a manner similar to a sampling oscilloscope. The output is a time-resolved bit error rate measurement on a microsecond time scale. We then use this technique to quantify the transient locking characteristics of commercial datacom transceivers as a function of the nominal received power, the power offset between the channels being switched, and the transition time of the optical switch. These results enable research into optical circuit-switched networks based on commercial datacom transceivers.