On Tue, Jul 13, 2010 at 10:04 PM, Peter Gutmann <pgut001@cs.auckland.ac.nz> wrote:
... A very small entity that (in its analog form) requires custom manufacturing steps, is affected by every minor change to the material, the process, die shrinks, you name it, and that most customers don't even know exists. So you need to rework, re-evaluate, and re-test it every time anything changes, and your customer won't pay extra for it.
i agree completely on all of the sad realities related to the non-existence of pervasive hw crypto facilities. the power consumption argument is a strawman though. the VIA docs stated a power consumption difference when XSTORE is configured and polled frequently vs. explicitly disabled and unused. the details are fuzzy though, and i suspect it's the rest of the pipeline around actual use of HWRNG state and moving across cache/bus lines... i would be curious to know the power details on any of the hw entropy sources, if any are out there. best regards,