Bonding geometries are disclosed between permanent magnets and steel portions of magnetic assemblies. The invention is characterised in that said moulding tools have pairs respective conical support surfaces, through which the tools are centred and aligned with one another, each support surface being formed by a portion of tools deprived of transverse mobility. In this manner, a second network address allocated to the second subscriber of services of either the first or second service providers is assigned to the network access device to enable the network access device to communicate data packets to the service network providing the selected service. When the change system determines that the change is consistent, it updates the data accordingly.