Abstract
WDM in optical networks are high capacity networks based on optical technologies in which RWA (Routing Wavelength Assignment) is a main issue. In this paper we have given overview on different rerouting schemes and also the survivability concept in case of failure occurs in network. That means most of the attention devoted in this paper on used of routing and wavelength assignment (coloring) scheme in first phase and rerouting in later phase. Therefore, after analysis it is clear that as compared to other schemes our propose rerouting at connection level (RRCL) scheme which is a cost effective approach with respect to different metrics terms. Finally we can say rerouting at connection level scheme works well in WDM optical networks and we demonstrate the performance of RRCL scheme through simulation results.