—Lightpath reconfiguration performance has been evaluated experimentally for regional IP-over-WDM network applications, making the network scalable and stable when traffic changes occur. The reconfiguration performance was examined in an experimental network with reconfigurable optical add/drop multiplexers (R-OADMs) to connect 4 nodes with bi-directional dual-fibers. The experiment was conducted by controlling the ROADMs. The control signals were sent by a developed system over WWW (World-Wide-Web). The lightpaths were added or deleted by the control system in the experimental network, and IP packets were monitored. The results clarified that lightpaths could be reconfigured by controlling the R-OADMs, and IP packets could be routed dynamically by OSPF (Open Shortest Path First) so as to adapt the lightpath changes. The reconfiguration functions of the system together with the ROADMs provide network administrators with easy management for the network in a skill-less, centralized and...