COMMUNICATION NETWORK SYSTEM, VEHICLE, COUNTER VALUE NOTIFICATION NODE, COUNTER VALUE SHARING METHOD, AND COMPUTER PROGRAM

摘要

PROBLEM TO BE SOLVED: To improve efficiency of a communication network system that connects a transmission node for transmitting a message and a reception node for receiving the message.SOLUTION: In a communication network system that connects a transmission node for transmitting a message and a reception node for receiving the message, a counter value notification message is regularly transmitted that notifies the transmission node and the reception node of a counter value used for generating and inspecting a message authentication code of the message.SELECTED DRAWING: Figure 6