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Comment by sweis | Hacker News Reader

Are you recommending DDR3 memory because you think it's resistant to cold boot or reset attacks?

That is not the case. DDR3 memory will not help you.

Certainly DDR3 memory (as a type of main memory) has less permanence than hard disks (i.e. secondary storage). It's a side effect not a desired goal.

Especially if you're bit-flipping sensitive stuff, there's probably a good hope for protection from recovery at normal temperature after what, 30-60 seconds? So reset is an issue, but "keep sensitive things in RAM vs. on disk" is still a reasonable security precaution.

maybe they meant ECC memory?

Is ECC more secure than regular consumer grade memory?

More "secure" from single bit errors, but not for recovery -- kind of the opposite goal. The big difference is DRAM (mostly the same, including DDR3) vs. SRAM (of several types -- relevant due to use in HSMs, cpu cache, etc.). DRAM has been getting worse/longer duration as it becomes lower power, so arguably DDR3 (being relatively new) would be worse than 1985 RAM.

CPU registers are the safest place against this attack (hence stuff like TRESOR where AES keys are held in CPU registers), but are by necessity limited (especially on x86; SPARC was better, and some of the new extensions to x86 help (SSE, etc.)

Most of this has been mitigated to some extent by periodic inversion of sensitive strings in main memory (keys, usually) -- this has been implemented in ~all crypto libraries.

SRAM's huge advantage is you can clear it faster than DRAM, but that doesn't help if you can somehow prevent the clearing from happening.

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