A VMM Security Kernel for the VAX Architecture

This paper describes the development of a virtual-machine monitor (VMM) security kernel for the VAX architecture. The paper particularly focuses on how the system’s hard-ware, microcode, and soft ware are aimed at meeting Al-levcl security requirernents while maintaining the standard interfaces and applications of the VMS and ULTRIX–32 op-erating systems. The VAX security kernel supports multiple concurrent virtual machines on a single VAX system, provid-ing isolation and controlled sharing of sensitive data. Rigor-ous engineering standards were applied during development to comply with the assurance requirements for verification and crmfigurat ion management. The VAX security kernel has been developed with a heavy emphasis on performance and on system management tools. The kernel performs suf-ficiently well that all of its development is now carried out in virtual machines running on the kernel itself, rather than in a conventional time-sharing system.