Congestion removing performance of stackable ROADM in WDM networks under dynamic traffic

Congestion removing performance has been investigated in IP-over-CWDM networks with reconfigurable optical add/drop multiplexers (ROADMs) for the best-effort transmissions specified by the service level agreement (SLA). Mathematical models and experimental results for two approaches: automated addition of new lightpath and creation of a static bypass route in other existing lightpaths, were presented in this paper. The experimental results clarified that the congestions were removed successfully in both the approaches. Addition of new lightpath approach can provide effective adjustment of larger traffic whereas the creation of a static bypass route approach can provide fine granularity adjustment of small traffic to be switched without lightpath reconfiguration. The degraded throughput was recovered within the recovery time specified by the SLA.