Efficient update scheme in photonic router

A photonic router that uses variable-length optical gates has been developed and experimentally demonstrated at a data transmission speed of 10 Gbit/s, but it is difficult to update the routing table. We present a fast update scheme in the photonic router. Our scheme is driven by the hierarchy of prefixes in the routing table. On applying the scheme to a set of real route update traces obtained from the Internet core, we find that they can produce no more than 100 movements for 10,000 inserting operations. Further, when compared to an existing algorithm, in the average case, our algorithm shows a 90% reduction of movement overheads.