This paper presented and described solution methods for a variant of the multicommodity Network Design problem(MCNDP) where congestion at nodes is explicitly taken into account. The so-called congested MCNDP (cMCNDP) aims at finding flows for each type of commodity by activating suitable arcs and performing capacity upgrades at nodes, so as to
minimize a function including operational and congestion costs, and by meeting capacity constraints on both arcs and nodes