The National Computer Security Center has issued guidance for trusted computer networks called the Trusted Network Interpretation (TNI) of the Trusted Computer System Evaluation Criteria (TCSEC). The TNI provides requirements for trusted computer networks that extend the guidance provided for traditional stand-alone computer systems by the TCSEC. It is expected that this Department of Defense (DOD) technical security guidance will be used as the basis for certification of DOD network system acquisitions. The author presents three major steps illustrating an application of the TNI. The steps are: formulating a TNI view; determining the appropriate TNI security requirements that will apply; and formulation of a network security architecture based on the allocation of the determined security requirements.>

Microcode compaction is an essential tool for the compilation of high-level language microprograms into microinstructions with parallel microoperations. The purpose of the research reported in this paper is to compare four microcode compaction methods reported in the literature: first-come first-served, critical path, branch and bound, and list scheduling. In order to do this a complete, machine independent method of representing the microoperations of real machines had to be developed; and the compaction algorithms had to be recast to use this representation. The compaction algorithms were then implemented and tested on microcode produced by a compiler for a high-level microprogramming language. The results of these experiments were that for all cases examined the first-come first-served and list scheduling algorithms produced microcode compacted into a minimal number of microinstructions in time that was a polynomial function of order two of the number of input microoperations.