Implications (cont.)
It is likely that the physical layer parameters do not change value rapidly and could be stored in some database; however these are physical layer parameters that today are frequently not known at the granularity required. If the ingress node of a lightpath does path selection these parameters would need to be available at this node.
In situations where only PMD and/or ASE impairments are potentially binding the optimal routing problem with the two constraints, OSPF algorithm enhancements will be needed. However, it is likely that relatively simple heuristics could be used in practice.