Passengers on board a vehicle make and receive calls via a satellite network. That network sees each passenger involved in a call as a temporary dummy subscriber of the satellite network. Thus the satellite network is used to manage the roaming of passengers on aircraft. An intermediate network and the terrestrial mobile telephone network therefore do not need to manage the roaming of the aircraft. The terrestrial mobile telephone network sees each node of the intermediate network as a dummy base station and each passenger involved in a call as a dummy mobile subscriber of the terrestrial mobile telephone network, in the service area of one of the dummy base stations. The terrestrial fixed telephone network sees each passenger involved in a call as a subscriber of another fixed network managed by another operator. The intermediate network sees the satellite network as a standard terrestrial mobile telephone network, able to manage the roaming of its subscribers itself.