Before revision: ¹ An assembly level is defined as intermediate level when the subsystem contractor prefers to contract a group of units with complex interfaces to another contractor (for instance the operating system and subsystem application software can be an assembly of the data management subsystem) .
After revision: ¹ An assembly level is defined as intermediate level when the subsystem contractor prefers to contract a group of units with complex interfaces to another contractor (for instance the operating system and subsystem application software can be an assembly of the data management subsystem)