In optical transport networks algorithms dealing with the lightpath selection process select routes and assign wavelengths based on the routing information obtained from the network state databases. Unfortunately, due to some factors, in large dynamic networks this routing information may be nonaccurate enough to provide successful routing decisions. In this paper we suggest a new prediction-based routing mechanism where lightpaths are selected based on prediction decisions. Consequently, the routing information is not required at all, so updating this information is neither required. In short, the signaling overhead produced by the updating process is practically removed Keywords. Optical routing, routing inaccuracy, prediction-based routing.