Given a maritime liner network, the cargo routing problem consists of determining which maritime routes containers will take to be transported from their loading port to their destination port. This constrained optimization problem is an essential task in the context of maritime commodity transportation, both in terms of network design and operational implementation. Several variants of this problem have been considered depending on their usage (e.g. for designing the network or for carrying containers in practice), the constraints taken into account or the criterion to be optimized. In this article, we address several variants of this problem, relying on the flexibility of Constraint Programming. First, we propose two general COP models. Then, we describe a local search method that can be easily adapted to the desired context. Finally, we experimentally compare our two models and the proposed method.

The liner shipping network design problem consists, for a shipowner, in determining, on the one hand, which maritime lines (in the form of rotations serving a set of ports) to open, and, on the other hand, the assignment of ships (container ships) with the adapted sizes for the different lines to carry all the container flows. In this paper, we propose a modeling of this problem using constraint programming. Then, we present a preliminary study of its solving using a state-of-the-art solver, namely the OR-Tools CP-SAT solver.