Research On Non-cooperative Game Of Security And Communication Delay Of CAN Bus Network

CAN bus local area network is a broadcast-based network.Due to its high real-time performance and reliability,and short frame structure,it is widely used in the intelligent connected car industry.However,there are strict conditions in this industry for security performance and quality of service(referred to as real-time in this article).On the CAN bus,data is broadcasted in clear text to all EDUs(electronic control units)connected to the bus,so there are threats in security.In order to improve the security of the system,it is necessary to encryption or authentication algorithm technology.However,it will occupy the original limited bandwidth resources,and will also cause delay of the system,which is a great challenge to the real-time requirements.On the contrary,in order to improve the real-time performance of the system,it is necessary to reduce the unnecessary occupation of the bus resources(including the required resources to enhance the security),which will undoubtedly reduce the security.Therefore,this question worth a further research on how to make security and delay,two conflict issues in a balance status.In the paper,we treat the security side and time-delay side as two participants through the mathematical methods(game theory).By constructing a non-cooperative game model and conducting a quantitative analysis,the Nash equilibrium is reached and the system reaches an efficient stable state.First,we take steps to verify all electronic control units,and then give random sequences(seed keys)to legal EDUs and gateways.The gateway and the verified ECU generate the same message authentication code MAC table and synchronization counter.When sending a message,the corresponding MAC value is added behind the data frame.The gateway and the receiving ECU determine whether the MAC in the data frame is the same as the MAC in the MAC table corresponding to its own counter value;if yes,the data frame is safe;otherwise it is a Illegal frame;the counters of the sending ECU,gateway,and receiving ECU are increased by 1,to determine the counters of the sending ECU,gateway,and receiving ECU Whether the value exceeds a predetermined threshold;if yes,the MAC table is regenerated;otherwise,the next frame communication is performed,and the next data frame communication is performed.This paper proposes a broadcast authentication algorithm,and establishes a MAC table,and combines the theory of Nash equilibrium to analyze the length of MAC sequence of the “security side” and the number of data frames that satisfied to the MAC of the “communication delay side”,and how to maximize the benefits at the least cost.