A set of critical nodes or links is identified on the network through which most of the shortest paths on the network occur. Each node compares their distance to end points on the network with a distance between the end points and each of the distinct critical nodes. Where the distance between the end points and the critical nodes is shorter than the distance between the end points and the node, the node is not on the shortest path and does not install forwarding state. Where the distance between the end points and the critical node is larger than or equal to the distance between the end points and the node, the node may be on the shortest path between the pair of end nodes and installs forwarding state. Installation of forwarding state may cause packet duplication, but determining forwarding state is dramatically simplified.; The level of duplication may be reduced by selecting a larger number of critical nodes on the network.