The invention comprises an overlay network that can be under full control of a service provider. Routing of packets between nodes in said overlay network is performed by means of an underlying large communication network. The nodes in the overlay network comprises specific nodes in the large communication network. Therefore, routing of packets according to the invention is transparent for nodes not belonging to the overlay network. One or more federative nodes manages the routing information. The federative nodes are connected to the network and comprise a computer and software, designed for providing said management of the routing information. The management of routes in the overlay network may of course be distributed over several hosts, for scalability of large overlay networks and reliability reasons. A purpose of the invention is to enable a user organization to control the routing of packets for their overlay network via different external networks.