On the minimum cost multiple-source unsplittable flow problem

The minimum cost multiple-source unsplittable flow problem is studied in this paper. A simple necessary condition to get a solution is proposed. It deals with capacities and demands and can be seen as a generalization of the well-known semi-metric condition for continuous multicommdity flows. A cutting plane algorithm is derived using a superadditive approach. The inequalities considered here are valid for single knapsack constraints. They are based on nondecreasing superadditive functions and can be used to strengthen the relaxation of any integer program with knapsack constraints. Some numerical experiments confirm the efficiency of the inequalities introduced in the paper.