Requirements and Technical Trade-Offs for a Communication Standard in a Data-Driven and Interconnected Aircraft Cabin (SAE Paper 2021-01-0011)
Current communication architectures in the aircraft cabin are mostly proprietary and limited to the boundary of the system, i.e. existing cabin systems operate mostly isolated from each other. Modern system design, however, requires a shared communication platform in order to enable novel services by means of a contract-based data and information exchange. Data-driven predictive maintenance applications are one example for which the fundamentals are studied intensively, but its integration into a multi-system environment with respect to communication requirements is often neglected. As the aircraft cabin is a highly dynamic environment with changing air pressure, humidity, temperature, and flight attitude, context information is needed in order to get meaningful predictions for e.g. the Remaining Useful Life (RUL) of a system, component or item. Also, novel passenger-related services such as meal ordering from the seat with a passenger-, route- and inventory-specific menu require the exchange of information between multiple systems. These examples emphasize that the underlying communication protocol has to handle a wide range of data update rates, amount of exchanged data, and communication patterns such as fault-tolerant one-to-many and reliable one-to-one communication. In this paper, the requirements of a contract-based multi-system information exchange will be analyzed, detailed and transformed into requirements for the communication protocol under development. These requirements consider different paradigms for data exchange, access control, encoding, and addressing schemes. Addressing schemes need to be designed carefully as software is deployed on network nodes in different cabin configurations, but may always process the same type of information, e.g. the state of all ovens in all the galleys. For each set of derived requirements for the communication protocol, technical concepts are presented and their technical trade-offs are discussed.