Before revision: Software level The Software Level, also known as the Design Assurance Level (DAL) or Item Development Assurance Level (IDAL) as defined in ARP4754 (DO-178C only mentions IDAL as synonymous with Software LevelRTCA/DO-178C "Software Considerations in Airborne Systems and Equipment Certification", p. 116.
After revision: Software level The Software Level, also known as the Development Assurance Level (DAL) or Item Development Assurance Level (IDAL) as defined in ARP4754 (DO-178C only mentions IDAL as synonymous with Software LevelRTCA/DO-178C "Software Considerations in Airborne Systems and Equipment Certification", p. 116.