A computer-implemented method for authenticating data frames in a vehicle network, comprising: storing, by a receiving electronic control unit, a cryptographic key, where the cryptographic key is shared with a sending electronic control unit; receiving, by the receiving electronic control unit, a current frame identifier in a data frame sent via a serial data link by the sending electronic control unit, wherein the data frame does not include an identifier for the receiving electronic control unit; generating, by the receiving electronic control unit, a next frame identifier in response to receiving the current frame identifier, where the next frame identifier is derived in part based on the received current frame identifier and the cryptographic key using an encoding function; storing, by the receiving electronic control unit, the next frame identifier in a data store for subsequent processing; receiving, by the receiving electronic control unit, another data frame subsequently to receiving the current frame identifier; extracting, by the receiving electronic control unit, a frame identifier from the another data frame without decoding any portion of the another data frame; comparing, by the receiving electronic control unit, the extracted frame identifier to the next frame identifier residing in the data store; processing, by the receiving electronic control unit, payload of the another data frame when the extracted frame identifier matches the next frame identifier; and discarding, by the receiving electronic control unit, the another data frame when the extracted frame identifier does not match the next frame identifier. storing, by a receiving electronic control unit, a cryptographic key, where the cryptographic key is shared with a sending electronic control unit; receiving, by the receiving electronic control unit, a current frame identifier in a data frame sent via a serial data link by the sending electronic control unit, wherein the data frame does not include an identifier for the receiving electronic control unit; generating, by the receiving electronic control unit, a next frame identifier in response to receiving the current frame identifier, where the next frame identifier is derived in part based on the received current frame identifier and the cryptographic key using an encoding function; storing, by the receiving electronic control unit, the next frame identifier in a data store for subsequent processing; receiving, by the receiving electronic control unit, another data frame subsequently to receiving the current frame identifier; extracting, by the receiving electronic control unit, a frame identifier from the another data frame without decoding any portion of the another data frame; comparing, by the receiving electronic control unit, the extracted frame identifier to the next frame identifier residing in the data store; processing, by the receiving electronic control unit, payload of the another data frame when the extracted frame identifier matches the next frame identifier; and discarding, by the receiving electronic control unit, the another data frame when the extracted frame identifier does not match the next frame identifier. <EOS>