Stabilized Column Generation for the Rooted Delay-Constrained Steiner Tree Problem

We consider the rooted delay-constrained Steiner tree problem which arises for example in the design of centralized multicasting networks where quality of service constraints are of concern. We present a path based integer linear programming formulation which has already been considered in the literature for the spanning tree variant. Solving its linear relaxation by column generation has so far been regarded as not competitive due to long computational times needed. In this work, we show how to significantly accelerate the column generation process using two different stabilization techniques. Computational results indicate that due to the achieved speed-up our approach outperforms so-far proposed methods.