September 18-20, 2024 | DoubleTree by Hilton, San Jose, California

CPU Equivalency Working Group Panel Report and Discussion (G32b)

CPU Equivalency Working Group Panel Report and Discussion (G32b)

Over the last several years, both CMVP and NIAP have been reducing the number of similar CPUs covered by a single CAVS test. Historically, an ARM was an ARM, an x86 was an x86 and a CAVS test for one, covered all family variants. But recently that has been changing and both bodies have been narrowing the definition of equivalence, sometimes to a single part number. The result is that a vendor validating a module may have to do as many sets of CAVS tests as the number of processors they support and validate/certify. This has become a very significant burden with some vendors having to do hundreds of CAVS tests for each new release of a module. The question of ‘what exactly is an equivalent CPU,’ has become a serious topic of discussion. In the hope of developing a good technical way of determining that, a workgroup was formed with both CMVP and NIAP participation to examine the issue and to come up with a recommendation.

This panel will have representatives from the developer, lab and standards communities and will discuss the determining of equivalence which has proven to be a much more difficult question than originally thought. Since CPUs are now really systems on a chip (SOC), with different firmware and microcode levels, how is it possible to accurately determine equivalence? How can it be tested and confirmed, and how many CPUs in a family can really be deemed equivalent?

I am submitting this as the moderator of the working group and the moderator of the panel. Panel members are still being decided, but will likely include Ed Morris, Kelvin Desplanque, a representative from Apple and a representative from NIST.