Method for protected communication by a vehicle, characterized by the steps of: - generating a key pair consisting of a private key and a public key and/or one or more symmetric keys for the vehicle or for a control unit (28, 30, 32) of the vehicle in the area of influence of the vehicle manufacturer, wherein a generating of the key pair and/or of the one or more symmetric keys for the vehicle or for a control unit (28, 30, 32) of the vehicle results in a serial number of the vehicle and/or of the control unit (28, 30, 32) being stored in the area of influence of the vehicle manufacturer; - generating a first certificate using the key pair, - introducing the key pair and the first certificate and/or the symmetric key or the multiple symmetric keys into the vehicle or the control unit (28, 30, 32), in the form of an encrypted and signed key data record; - authenticating the vehicle or the control unit (28, 30, 32) to a new communication partner (38, 40) by generating a new key pair for this communication path and sending a signed message together with the first certificate, wherein a master key is generated in the area of influence of the vehicle manufacturer and all of the keys used in the vehicle are generated by deterministic derivation from the master key, wherein a fresh request for a key pair and/or a key, if a serial number of the vehicle or of the control unit (28, 30, 32) is not concordant with the stored serial number, results in the calculation of a new key pair and/or key to be transmitted to the vehicle or to the control unit (28, 30, 32) being preceded by a key identity counter of the key pair and/or key being incremented and a new key being generated thereby, wherein the vehicle or the control unit (28, 30, 32) accepts the new key pair and/or the key or the multiple keys only if the included key identity counter is greater than or equal to the currently stored key identity counter, and - authenticating the new communication partner (38, 40) to the vehicle or the control unit (28, 30, 32) using a signed message and a public key of the new communication partner (38, 40), which are produced by the new communication partner (38, 40) on the basis of a certification by the vehicle manufacturer. - generating a key pair consisting of a private key and a public key and/or one or more symmetric keys for the vehicle or for a control unit (28, 30, 32) of the vehicle in the area of influence of the vehicle manufacturer, wherein a generating of the key pair and/or of the one or more symmetric keys for the vehicle or for a control unit (28, 30, 32) of the vehicle results in a serial number of the vehicle and/or of the control unit (28, 30, 32) being stored in the area of influence of the vehicle manufacturer; - generating a first certificate using the key pair, - introducing the key pair and the first certificate and/or the symmetric key or the multiple symmetric keys into the vehicle or the control unit (28, 30, 32), in the form of an encrypted and signed key data record; - authenticating the vehicle or the control unit (28, 30, 32) to a new communication partner (38, 40) by generating a new key pair for this communication path and sending a signed message together with the first certificate, wherein a master key is generated in the area of influence of the vehicle manufacturer and all of the keys used in the vehicle are generated by deterministic derivation from the master key, wherein a fresh request for a key pair and/or a key, if a serial number of the vehicle or of the control unit (28, 30, 32) is not concordant with the stored serial number, results in the calculation of a new key pair and/or key to be transmitted to the vehicle or to the control unit (28, 30, 32) being preceded by a key identity counter of the key pair and/or key being incremented and a new key being generated thereby, wherein the vehicle or the control unit (28, 30, 32) accepts the new key pair and/or the key or the multiple keys only if the included key identity counter is greater than or equal to the currently stored key identity counter, and - authenticating the new communication partner (38, 40) to the vehicle or the control unit (28, 30, 32) using a signed message and a public key of the new communication partner (38, 40), which are produced by the new communication partner (38, 40) on the basis of a certification by the vehicle manufacturer.