: We consider the routing and the wavelength assignment (RWA) of scheduled and random lightpath demands in a wavelength switching mesh network without wavelength conversion functionality. Scheduled lightpath demands (SLDs) are connection demands for which the set-up and tear-down times are known in advance as opposed to random lightpath demands (RLDs) which are dynamically established and released according to a random pattern of requests. Two routing strategies are proposed which process the SLDs and the RLDs separately. The first routing strategy allows to bifurcate the traffic on several routes connecting the source to the destination of a demand whereas the second strategy forces atomic routing. The routing strategies are compared through rejection ratio.