Integrated modular avionics (IMA) are real-time computer network airborne systems.
This network consists of a number of computing modules capable of supporting numerous applications of differing criticality levels.
However, much complexity is added to the systems, which thus require novel design and verification approaches since applications with different criticality levels share hardware and software resources such as CPU and network schedules, memory, inputs and outputs.
Partitioning is generally used in order to help segregate mixed criticality applications and thus ease the verification process.
ARINC 653 contributes by providing a framework that enables each software building block (called a partition) of the overall Integrated modular avionics to be tested, validated, and qualified independently (up to a certain measure) by its supplier.