# A Multi-Layer Secure Sharing Framework for Aviation Big Data Based on Blockchain
## 3 Analysis of ATM Big Data Sharing
### ATM System Concepts
#### 3.1.3 Key Element  
ATM is a highly integrated complex system whose efficient operation relies on the coordinated collaboration of hardware infrastructure, software systems, multiple participating entities, and data resources. These key elements collectively constitute the core architecture of ATM, ensuring the safety, orderliness, and efficiency of air transportation.  
As the physical foundation of ATM, hardware includes critical equipment such as surveillance, navigation, communication, and meteorological detection systems. Surveillance systems (e.g., radar, ADS-B, MLAT) track aircraft positions in real time; navigation systems (ground-based VOR/DME and space-based GNSS) provide precise route guidance; communication systems (VHF, CPDLC, SATCOM) enable air-ground information exchange; and meteorological equipment supports weather warnings and route optimization. These hardware components serve as the \"sensors\" of ATM, providing physical-layer perception and interaction capabilities.  
Software systems act as the \"nerve center\" of ATM, responsible for data processing, decision support, and operational optimization. ATM automation systems (e.g., FDP, RDP) manage flight plans and trajectory tracking; decision support tools (STCA, MSAW) assist controllers in risk identification; and simulation systems are used for personnel training and contingency plan validation. These software components transform raw data collected by hardware devices into actionable control decisions, significantly enhancing system response speed and management precision.  
ATM participants include air traffic service providers, airline operators, regulatory agencies, and technical support units. ATC units (area control, approach control, tower) are responsible for real-time command; airlines execute control instructions and provide operational feedback; international organizations (ICAO) and national agencies (FAA,EASA) establish standards and regulations; and equipment manufacturers and technical service providers offer system support. This multi-party collaboration mechanism ensures the reliability and safety of ATM operations through clear division of responsibilities while also imposing higher requirements on the system's overall collaborative decision-making capability.  
Data resources serve as the \"lifeblood\" connecting all elements, running through the entire ATM operation process. The sharing and exchange of data such as aircraft dynamic data (position, altitude, speed), airspace structure data (routes, sectors), meteorological information (real-time weather, forecasts), and operational management data (flight plans, delay statistics) provide a quantifiable decision-making basis for ATM operations. These data not only support daily operational management but also serve as important references for system performance evaluation and continuous optimization. These four elements do not exist in isolation but form an organic whole through continuous interaction: hardware collects data, software processes information, participants make decisions, and data flows both transmit information and feed back into system optimization.