1. A computer-implemented method for managing structures in stochastic networks comprising: creating a general analytical model for a stochastic network; decomposing the general analytic model into a set of one or more decomposed analytic models; generating an optimization problem based on one or more of: capacities and structures in each of the one or more decomposed analytic models; obtaining an approximate solution to the optimization problem including identifying a value for the one or more of capacities and structures for the set of analytic models as an intermediate solution for the one or more of: capacities and structures of the stochastic network; and, determining the one or more of: capacities and structures for the stochastic network based on the intermediate solution, wherein a programmed processor device is configured to perform one or more of the creating, decomposing, generating, obtaining and determining