## 2 Related Work
### Contribution and Organization  
According to the \"Civil Aviation Cyberspace Security Strategy\" formulated by ICAO and the \"Civil Aviation Net-work Information Security Management Regulations (Provisional)\" promulgated by the Civil Aviation Administration of the Ministry of Communications of China, the key tasks of this paper are \"to strengthen the information integration of civil aviation networks, analyze the security threats, comprehensively grasp the development situation of civil aviation network information security, and build a civil aviation network information security assurance system\". This paper formulates four research contents on the basis of the four key tasks, and their relationships are shown in Figure 3.  
The Civil Aviation Cyberspace Security Strategy released by ICAO points out that the main threat to networked ATM is the prevention of information spoofing, data injection, entity masquerading, and DDoS attack, which lead to inaccessibility or normal use of ATM services. On the basis of the ATM-CPS model and its game model, this paper uses blockchain technology to establish a trustworthy model of ATM from the key technical dimensions of security protection, security assessment, and situational awareness. The information security assurance architecture of networked ATM based on the trustworthy model is proposed, and a systematic research plan is proposed for the information security problems of networked ATM security.  
The thought behind the research in this paper is to perform cyber-physical fusion for space units (communication and navigation satellite networks), air units (air surveillance networks and airborne networks) and ground units (ATC operation centers, data centers, ATM departments, airlines, airports, and ground stations) to form ATM-CPS (Figure 4). Further, for the security threats of ATM-CPS, the information security properties of networked ATM are determined by special analysis based on the SSE theory, the security properties satisfied by ATM are mathematically proved, the potential attacks faced by ATM are mined using the formal verification method, and various optimization objectives and optimization functions are designed to establish the ATM-CPS threat model. Then, using Bayesian game theory, we simulate the attack characteristics of the attack mode in the real ATM-CPS and the defense characteristics of the networked ATM on the basis of the security baseline strategy to form a non-cooperative game with incomplete information and establish the ATM-CPS game model on the basis of Bayesian Nash equilibrium. Finally, blockchain technology is used to establish a trustworthy mechanism for ATM-CPS, and  
Figure 2: Deficiencies in related work.  
cryptographic algorithms are used to implement access authentication among data chains and networks, and then an integrated ATM-CPS space-air-ground security assurance architecture is constructed on the basis of the blockchain trustworthy model.  
Figure 4: The overall research proposal.  
Figure 3: Research contents and the relationships among them.  
This paper is organized as follows. Section 3 outlines the current issues and trends in ATM security according to the actual needs. Section 4 presents the networked ATM-CPS model and its threat model. Section 5 introduces the networked ATM-CPS game model. Section 6 describes the networked ATM-CPS security assurance architecture. Section 7 provides the scientific problem solved by networked ATM-CPS and the implementation deployment route. Finally, Section 8 draws conclusions.