Methods and devices for improving the reliability of communication between an aircraft and a remote system. The aircraft transmits a request for verification of security to a remote system. Upon reception of the response to this request, which includes at least one indication pertaining to the security of the remote system, the aircraft analyzes this indication and decides to establish or not to establish data communication between the aircraft and the remote system. When a verification request is received, the remote system is verified and a response to the request is transmitted to the aircraft.