A method may include obtaining a topology of an optical network. The topology may indicate multiple optical links within the optical network. The method may also include obtaining a routing metric for each of the optical links. The routing metric may be used in selecting routes through the optical network along the multiple optical links. The method may further include obtaining a signal noise tolerance of an optical signal to be routed through the optical network and adjusting routing metrics of one or more of the multiple optical links based on the signal noise tolerance of the optical signal. The method may also include after the routing metrics of the one or more of the multiple optical links are adjusted, determining a route for the optical signal through the optical network along two or more of the multiple optical links based on the routing metrics of the multiple optical links.