A communication method performed by a first electronic control unit, ECU, , the communication method comprising: determining (S101), an authentication key based on a first value and a shared key; splitting (S102) the authentication key to obtain a first key and a second key; assembling (S 103) a controller area network, CAN, frame by using the first key and the second key, wherein the first key is used to encrypt a valid data payload, and the second key is used to randomize a location of a cyclic redundancy check, CRC, bit in a data payload field; and sending (S 104) the CAN frame to a second ECU through a CAN bus, wherein the first value is a value broadcast by a manager based on a time segment, and the shared key is a key shared by all ECUs in a vehicle; characterized in that the assembling a CAN frame by using the first key and the second key comprises: generating a keystream based on the first key; performing an exclusive OR operation on the keystream and data corresponding to the valid data payload, to obtain encrypted data; determining the location of the CRC bit in the data payload field based on values of bits in the second key; placing each CRC bit into a corresponding payload bit based on the location of the CRC bit in the data payload field; and placing the encrypted data into the remaining payload bits in the data payload field, to obtain the assembled CAN frame. determining (S101), an authentication key based on a first value and a shared key; splitting (S102) the authentication key to obtain a first key and a second key; assembling (S 103) a controller area network, CAN, frame by using the first key and the second key, wherein the first key is used to encrypt a valid data payload, and the second key is used to randomize a location of a cyclic redundancy check, CRC, bit in a data payload field; and sending (S 104) the CAN frame to a second ECU through a CAN bus, wherein the first value is a value broadcast by a manager based on a time segment, and the shared key is a key shared by all ECUs in a vehicle; characterized in that the assembling a CAN frame by using the first key and the second key comprises: generating a keystream based on the first key; performing an exclusive OR operation on the keystream and data corresponding to the valid data payload, to obtain encrypted data; determining the location of the CRC bit in the data payload field based on values of bits in the second key; placing each CRC bit into a corresponding payload bit based on the location of the CRC bit in the data payload field; and placing the encrypted data into the remaining payload bits in the data payload field, to obtain the assembled CAN frame. generating a keystream based on the first key; performing an exclusive OR operation on the keystream and data corresponding to the valid data payload, to obtain encrypted data; determining the location of the CRC bit in the data payload field based on values of bits in the second key; placing each CRC bit into a corresponding payload bit based on the location of the CRC bit in the data payload field; and placing the encrypted data into the remaining payload bits in the data payload field, to obtain the assembled CAN frame. <EOS>