1. A method for providing efficient aggregation of link metrics for a subnetwork in a communication network with an original subnetwork topology, comprising the steps of: 1A) selecting, by a predetermined subnetwork leader, a subset of nodes in the subnetwork to be exposed nodes, 1B) mapping, by the predetermined subnetwork leader, the original subnetwork topology, stored in a topology database of the subnetwork leader, to a full-mesh virtual topology wherein each virtual link connecting a pair of exposed nodes on the full-mesh virtual topology is derived utilizing a predetermined oath selection optimization, 1C) for each link metric that characterizes a preselected plurality of information transfer of links in the subnetwork, generating, by the subnetwork leader, a spanning tree virtual topology connecting the exposed nodes, 1D) determining link metric values to the virtual links on the spanning tree and advertising the metric values in a topology broadcast to nodes outside the subnetwork, by the subnetwork leader, and 1E) estimating for each link metric, by nodes outside the subnetwork, link metric values for all virtual links on the full-mesh virtual topology connecting the exposed nodes based on the link metric values for the virtual links on a corresponding spanning tree, wherein a link metric value associated with each virtual link on the full-mesh virtual topology is an estimate of a link metric value associated with a corresponding virtual link in the original subnetwork topology.