Research On Survivability In Elastic Optical Network

With the extensive deployment of the optical network,there is a high chance for a backbone network to incur a failure.Thus,it is necessary to provide network protection in order to avoid the interruption of network application services.This thesis focuses on the network protection techniques for the elastic optical network to recover the single failure and dual failures.First,for an EON with single failure protection,we considered the shared backup path protection(SBPP)technique and explored the strategies on placement and usage of signal regenerators.Also,we developed a heuristic algorithm to serve dynamic lightpath traffic demands.Based on the simulation studies that evaluated the bandwidth blocking probability(BBP),we find that efficiently placing and using the signal regenerators can effectively reduce BBP.In addition,the conversion capabilities of modulation format and spectrum of a signal regenerator can also significantly reduce BBP for the EON.Moreover,we also observe that with an increasing number of regenerators,the performance improvement would became saturated,i.e.,a further increase of signal regenerators can only marginally improve the network BBP performance when the number of regenerators has reached a certain threshold level.In addition,for the dual-failure protection,we developed three network protection techniques,including 1:1:1,1+1:1,and 1+1+1.These techniques demonstrate different network protection resource sharing capabilities.Furthermore,we divided the 1:1:1 technique into two sub-cases,i.e.,dedicated 1:1:1 and mixed 1:1:1 depending on whether the two protection paths can inter-share their protection capacity.For each of the protection techniques,we developed integer linear programming(ILP)model as well as spectrum window plane(SWP)-based heuristic algorithm.The simulation studies indicate that with respect of protection resource sharing,1:1:1 can achieve the best performance,1+1+1 shows the lowest sharing efficiency,while 1+1:1 falls between the previous two.Moreover,mixed 1:1:1 can achieve better performance than dedicated 1:1:1.