Abstract: The deep penetration of optical transmission from the very edges of the network with optical access networks to the very core with routing data within data centers before transmission has resulted in competing demands for increased functionality, reduced cost, enhanced manufacturability, and reduced footprint. At the same time monitoring and fault detection with prior art optical time domain reflectometry systems have not kept up to the demands of these networks and systems as they are expensive test equipment based solutions. It would be beneficial to provide embedded OTDR functionality within each transmitter, receiver or transceiver deployed within the network allowing every link to be monitored continuously. It would be further beneficial for such embedded OTDRs to meet the demands for lower cost, high volumes, and smaller footprints with enhanced manufacturability.

Abstract: Today's communications require an effective yet scalable way interconnection of data centers and warehouse scale computers (WSCs) whilst operators must provide a significant portion of data center and WSC applications free of charge to users and consumers. At present, data center operators face the requirement to meet exponentially increasing demand for bandwidth without dramatically increasing the cost and power of the infrastructure employed to satisfy this demand. Simultaneously, consumer expectations of download/upload speeds and latency in accessing content provide additional pressure. Accordingly, the inventors provide a number of optical switching fabrics which reduce the latency and microprocessor loading arising from the prior art Internet Protocol multicasting techniques.