scope:

This document discusses those aspects of approval that pertain to the production of software for CNS/ATM systems. In discussing those aspects, the system life cycle and its relationship with the software life cycle is described to aid in the understanding of the approval process. A complete description of the system life cycle processes, including the system safety assessment and validation processes, or the approval process is not intended.

The guidance contained in this document does not define or imply the level of involvement of an approval authority in an approval process. To understand approval authority involvement, the applicant should refer to applicable regulations and guidance material issued by the relevant approval authority.

This document does not attempt to define firmware. Firmware such as embedded microcode or libraries should be classified as hardware or software and addressed by the applicable processes. This document assumes that during the system definition, functions have been allocated to either software or hardware. Other documents exist that provide guidance for development assurance for functions that are allocated to implementation in hardware. This document provides guidance for functions that are allocated to software.

NOTE: This allows an efficient method of implementation and development assurance to be determined at the time the system is specified and functions allocated. All parties should agree with this system decision at the time the allocation is made.