FAULT-TOLERANT VEHICLE COMMUNICATIONS

A method in a vehicle equipped with a long-range and a short-range interface comprises maintaining a connection to an access network using the long-range interface; recording a time and location at which the connection to the access network is operable; in case of failure of the connection to the access network, attempting to form a vehicle ad-hoc network (VANET) using the short-range interface; and sharing, with other vehicles in the VANET, the recorded time and location. Further, the vehicle may receive, from the other members of the VANET, a time and location at which the other members' connection to the access network was operable. From the time and location recorded by the vehicle and the time and location it receives, the vehicle derives coverage information indicative of a geographical boundary of an operable portion of the access network.