The inventory control is crucial for companies who wish to satisfy their customer demands on time as well as controlling costs. For this, it is necessary to be in possession of the necessary and sufficient components to produce the requested products n time. Indeed, a poor inventory control policy leads to overstocking or stockout situations. In the former, the generated inventories are expensive and in the later, there are shortages and penalties due to unsatisfied customer demands. In this thesis, we study the supply planning for the multilevel supply chains. The decision variables are the parameters of MRP (planned lead times). The aim is to provide ideas and methods on the MRP parameterization under lead time uncertainties. We proved interesting theoretical properties and we proposed the models methods for the optimization problems.
