Sub-reconfiguration of backup paths based on shared path protection for WDM networks with dynamic traffic pattern

The survivability of optical networks based on WDM technology is a critical concern. Shared path protection provides fast recovery from network failure. To ensure high resource usage efficiency, optimal configuration of lightpaths is needed. This is possible in static traffic but not so in dynamic traffic. How to reconfigure the WDM networks to accommodate changes in traffic demand poses a new challenge. Carrying out a full reconfiguration of all backup paths is a way to achieve a good performance. However, it is time-consuming and not for practical use. In this paper, we propose a new technique called sub-reconfiguration to rearrange the backup paths for WDM networks. This technique captures the property of backup path sharing to achieve fast reconfiguration of backup resources. So, the resource usage efficiency can be improved effectively. We carry out simulation experiments with dynamic traffic input. The results show that our sub-reconfiguration technique can save up to 10% wavelength usage and can significantly lower the protection overbuild. It can support fast reconfiguration and improve the resource usage efficiency effectively