A system for communicating cross-connection information within an optical network by use of wavelength information is provided. Cross-connection information in Wavelength Division Multiplexing (WDM) devices is abstracted, to produce wavelength reachability information and wavelength occupation status information for each node within the optical network. Cross-connection information is distributed from one node to all other nodes or a Path Calculation Equipment (PCE), through extended routing protocols, providing a base for calculating service paths.