An Effective Method for Guaranteed Shared Protection in WDM Optical Networks

0　IntroductionToday’sWDMopticalnetworkscanprovidehugebandwidthtotheirclientsandarebecomingauniquecan didateforthefutureInternettransportinfrastructure .However ,networkfailurewillinducelargetrafficlossbe causeallthelightpathsinopticalnetworkcarryalargevolumeofinformation .Soitisverynecessarytoprovideprotectionforworkinglightpaths .Theprotectionapproachescanbeclassifiedintopathprotectionandlinkprotectiondependingonwhethertheend to endorthelocalprotectionisused .Theycanalsobesortedintodedica…

An Effective Method for Guaranteed Shared Protection in WDM Optical Networks

Previous dynamic resource allocation methods (Separate Path Select, SPS) for survivable networks are always separated into two steps, that is, to determine an optimal primary path first and then select a backup path for the primary path. But SPS cannot achieve a good network performance. In this paper we analyze the drawback of the traditional SPS technique and propose an efficient shared protection method called MSPS. Instead of rejecting an arrival call immediately when a backup lightpath for the optimal primary lightpath cannot be found, MSPS continue to try the sub-optimal one until a legal primary-backup pair can be selected. We apply MSPS to CERNETLike and NSFNET networks. The results show that MSPS improves the network performance remarkably.