There is provided a method in a wavelength convertible flexible optical wavelength-division multiplexing (WC-FWDM) network. The network has a plurality of optical nodes interconnected by a plurality of optical fibers. The network is for providing an overall spectrum divisible into a set of consecutive wavelength slots. At least one optical node has at least one wavelength converter for wavelength conversion. The method includes determining a channel route through the network commencing at a source node and ceasing at a destination node. The determined channel route is selectively tunable responsive to selected ones of a plurality of routing methods. The routing methods are so selected responsive to a routing policy having one or more objectives of minimization of channel blocking, minimization of a number of wavelength converters used in the network, and minimization of physical distance traversed by a channel, and minimization of operating wavelengths of a channel.