2080	 The Nucleus of a Multiprogramming System	 This paper describes the philosophy and structure of a multiprogramming system that can be extended with a hierarchy of operating systems to suit diverse requirements of program scheduling and resource allocation. The system nucleus simulates an environment in which program execution and input output are handled uniformly as parallel cooperating process es. A fundamental set of primitives allows the dynamic creation and control of a hierarchy of processes as well as the communication among them. multiprogramming operating systems parallel processes process concept process communication message buffering process hierarchy process creation process removal
