Abstract: A sender configured to participate in an in-vehicle network is configured to receive a request for transmitting a payload and generate, in response, a first header in a transport layer and/or a network layer. The sender is further configured to access a key of k bytes length and to generate an authentication tag using the key and at least the first header as additional authentication data. The authentication tag serves to indicate an authenticity of a first frame on the transport and/or network layer as an original frame sent from the sender to a receiver. The sender is configured to generate the first frame comprising the first header, a transport layer payload, and the authentication tag and forward the first frame to the data link layer. The data link layer generates a second frame on the data link layer and transmits the second frame to the in-vehicle network.

Abstract: A transceiver is disclosed including a transmitter designed to output a first signal according to a physical communication protocol, and to output a second signal comprising at least one cryptographic datum. The first and the second signal may be overlaid onto one another as an overlay signal at the output of the transceiver, and may comply with the physical communication protocol. The overlay signal may be received and processed by a receiver.

Abstract: A transceiver is disclosed including a transmitter designed to output a first signal according to a physical communication protocol, and to output a second signal comprising at least one cryptographic datum. The first and the second signal may be overlaid onto one another as an overlay signal at the output of the transceiver, and may comply with the physical communication protocol. The overlay signal may be received and processed by a receiver.