Method and apparatus for globally optimizing a weighted flow network, including the procedures of collecting a plurality of metrics in the weighted flow network, receiving a plurality of route requests from a first node to a second node in the weighted flow network, determining K best routes out of N possible routes from the first node to the second node according to the plurality of metrics, balancing a load in the weighted flow network by distributing the plurality of route requests over the K best routes from the first node to the second node, and updating the plurality of metrics.