Assignment Criteria Proposal for Function Allocation to Security Domains of Aviation Systems

Aircraft cabin management is characterized by operational and business processes. Both are defined as a logical sequence of activities that occur during the flight. While the operational process includes activities to ensure flight safety, such as take-off, cruise and landing, the business process activities are related to adding value to the customer, i.e. the passenger. They are to be certified by the authority as a part of the aircraft type certification. These processes are defined by the airline and are described as part of the airline’s business model. While the scope of operational processes for passenger safety within the aircraft cabin should remain as unchanged as possible, the increasing competitive pressure on airlines is leading to a constantly rising number of services in the cabin. To prevent compromising cabin safety from increased cabin crew workload during the cruise phase, there is a growing trend toward digitizing operational and business processes. The digitized operational and business processes are leading the aircraft cabin systems to access information from different domains. The emerging need for digitalization, along with essential networking capabilities, has led to the development of an aircraft security domain model that groups functionalities based on system security considerations. For this domain model, partitioning, isolation, controlled communication, and security policies are specified. However, it lacks guidance on function allocation to specific domains. This paper addresses this gap by proposing assignment criteria for the allocation of functions to aircraft security domains, making the security domain standards easier to apply in daily aviation system development.