In one embodiment, a method includes receiving topology data that indicates multiple communication links and multiple intermediate network nodes in communication based on the communication links. The intermediate network nodes include multiple leaf nodes that terminate communications and multiple transit nodes that facilitate the passage of information between leaf nodes. Aggregation point data is also received, which indicates all aggregation points on the intermediate network nodes. An aggregation point is an interface between a network node and a communication link, through which is output data that is a combination of data received through multiple different interfaces upstream of the interface. A set of paths is determined for which each path in the set connects a different pair of leaf nodes. A measure of aggregation is determined based on a number of aggregated paths of the set of paths. An aggregated path passes through an aggregation point.