Separated Unicast/Multicast Splitter-and-Delivery Switch and Its Use in Multicasting-Capable Optical Cross-Connect

We propose a novel separated unicast/multicast splitter-and-delivery (SUM-SaD) switch for mixed unicast and multicast traffic. Only multicast connections undergo extra splitting loss but are compensated by incorporated optical amplifiers. A typical multicasting-capable optical cross-connect is constructed by using the proposed SUM-SaDs. Theoretically, we prove that it is strictly nonblocking for both unicast and multicast connections if d=N/2, where N and d are the dimension of SUM-SaD and the number of SaD input ports, respectively. Therefore, d means the maximum accommodated trees in the SUM-SaD. To save cost, d can be less than N/2 , and the throughput performance is investigated by simulation. The results show that the throughput is improved when d increases. In the experiment, we construct a 4 times 4 SUM-SaD prototype and measure the bit-error rate (BER) of unicast connection, multicast connection with or without optical amplifier. There is no clear BER difference between them for the small dimensional SUM-SaD switch.