Quality of service requirements for system wide information management (SWIM)

The ability of the National Airspace System (NAS) to provide safe separation is achieved by a skilled and dedicated work force operating with support from an automation infrastructure. Requirements for this infrastructure include measures of performance, availability, maintainability, accuracy, and security and are called quality of service (QoS) requirements. The value of the support provided by the infrastructure has been called system effectiveness. An algebraic approach to quantifying the QoS demands upon the SWIM infrastructure by the applications described in NAS Architecture 5 is being developed. An interface management system (IMS) collects this information while providing user support for creation of interface requirements documents, and is in a position to combine the various individual demands upon infrastructure resources to inform (and perform) calculations of aggregate demands upon infrastructure resources. Dynamic schedulability of system resources using Jensen utility functions, where system effectiveness is the utility measure, is anticipated to provide graceful degradation in the event of increased demands upon system capacity.