Ensuring Privacy through Distributed Computation in Multiple-Depot Vehicle Routing Problems

The Vehicle Routing Problem (VRP) has been extensively studied over the last twenty years, because it is an abstraction of many real-life logistics problems. In its multiple-depot variant (MDVRP), the routes of vehicles located at various depots must be optimized to serve a number of customers. In this paper, we investigate how to protect the privacy of delivery companies, when each depot is owned by a different company with a limited view of the overall problem. Companies then need to exchange messages with each other to coordinate the assignment of customers to depots. We show how Distributed Constraint Optimization (DCOP) can be used to solve the assignment problem using distributed computation, and we study the guarantees that can be provided with respect to the protection of each company’s knowledge about the problem.