1. A method for evaluation of optical paths in optical networks, the method comprising: based on a matrix M including all-optical reachability information for nodes in an optical network, generating sets of all-optical paths between a source node and a destination node, and wherein the all-optical paths include a minimum number of regenerators between the source node and the destination node; generating path cost information for the sets of all-optical paths, wherein the path cost information includes cost metric information for the sets of all-optical paths; based on the path cost information, calculating node cost information for each node associated with the all-optical paths to the destination node; generating a hierarchical guided search graph including the nodes associated with the sets of all-optical paths, optical path groups comprising optical paths between common nodes, the path cost information, and the node cost information; and based on the hierarchical guided search graph, determining a lowest cost optical path between the source node and the destination node.