A method and system are provided for operating a transmission system having connected nodes. Channels are assigned for carrying traffic along the connections according to a multiple protection classes. Traffic may then be propagated over the connections in accordance with the assigned protection classes.
System and method for dynamically assigning wavelengths wavelength division multiplex ("WDM") ring networks is described. In one embodiment, the invention comprises a method for dynamic wavelength assignment on a ring in a WDM network comprising, for each new requested traffic flow from a source node to a destination node on the ring, for each segment on a path around the ring between the source and destination nodes, classifying the new requested traffic flow into one of a set of spatial relationship types for each existing wavelength; determining a corresponding number of optical-to-electrical and electrical-to-optical ("OEO") interfaces needed for each spatial relationship type selected for each segment; determining the total number of OEO interfaces needed for the entire path between the source and destination nodes along the ring; and selecting the existing wavelengths that minimize the OEO interfaces.