Hi! > >sense of where the unpredictability might be coming from, and whether > >the unpredictability is coming from something which is fundamentally > >arising from something which is chaotic or quantum effect, or just > >because we don't have a good way of modelling the behavior of the > >L1/L2 cache (for example) and that is spoofing your entropy estimator. > > Please note: if the jitter really comes from the oscillator effect of > the RAM clock vs. the CPU clock (which I suspect), we will not be able > to alter the jitter software wise. Well... if it is really oscillator effect, there should be _no_ entropy when running with L1/L2 enabled (because DRAM will not be accessed at all at that case). There should be way to extract entropy more directly from various oscillator effects, no? For DRAM, just perform timing, have entropy. Plus we could for example measure PIT vs. other timer sources... (but I suspect that on PCs we already have enough entropy...) Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
