A method of routing packets in network system where the network system comprises a plurality of edge nodes and a plurality of core nodes. Selected core nodes are coupled to communicate with selected edge nodes. The network system also comprises a plurality of external nodes, with selected external nodes coupled to communicate with selected edge nodes, and where different external nodes are associated with a plurality of different entities sharing resources on the network system. The method comprises proposing a set of entities from the plurality of different entities. The proposed set comprises entities associated with external nodes that share respective connections to a number of edge nodes in the edge nodes such that the shared number is less than a total number of all edge nodes to which each different entity in the set is connected, with other aspects then taken with respect to the proposed set.