2632	 HYDRA The Kernel of a Multiprocessor Operating System	 This paper describes the design philosophy of HYDRA-the kernel of an operating system for C.mmp the Carnegie-Mellon Multi-Mini-Processor. This philosophy is realized through the introduction of a generalized notion of resource both physical and virtual called an object . Mechanisms are presented for dealing with objects including the creation of new types specification of new operations applicable to a given type sharing and protection of any reference to a given object against improper application of any of the operations defined with respect to that type of object. The mechanisms provide a coherent basis for extension of the system in two directions the introduction of new facilities and the creation of highly secure systems. operating system kernel nucleus protection security
