60,000 seconds was the amount of time it was tested for,
Surely if they already have a test setup, then having a test last for 600,000 seconds isn't very hard?
Things that look linear for a short period end up being exponential over longer periods. I don't think we can assume linear extrapolation here. There could be physics at play where exponential degeneration of the voltage occurs.
Its a good start of a test. But it seems weird in that a paper like this would have taken much more than ~1 week to write, so making a test last ~1 week for their calculations seems within the feasibility of this group. But its oddly missing data.
DRAM will also normally hold most of its data for 1000x longer than the rated (usually 60 ms) refresh time. This has sometimes been used to recover secrets from powered down computers. The rated refresh time is chosen to give near-zero errors over years of operation, accounting for worse-case leakage from any bit, but most bits leak much less than that.
I think older systems also tended to use a fixed refresh rate, rather than refreshing more often as the DRAM temperature rises. Temperature sensors on DRAM are more common now, so systems don't have to be so conservative with the refresh intervals.
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60,000 seconds was the amount of time it was tested for, they then extrapolate that out linearly. It doesn't need refreshing that often.
Surely if they already have a test setup, then having a test last for 600,000 seconds isn't very hard?
Things that look linear for a short period end up being exponential over longer periods. I don't think we can assume linear extrapolation here. There could be physics at play where exponential degeneration of the voltage occurs.
Its a good start of a test. But it seems weird in that a paper like this would have taken much more than ~1 week to write, so making a test last ~1 week for their calculations seems within the feasibility of this group. But its oddly missing data.
DRAM will also normally hold most of its data for 1000x longer than the rated (usually 60 ms) refresh time. This has sometimes been used to recover secrets from powered down computers. The rated refresh time is chosen to give near-zero errors over years of operation, accounting for worse-case leakage from any bit, but most bits leak much less than that.
I think older systems also tended to use a fixed refresh rate, rather than refreshing more often as the DRAM temperature rises. Temperature sensors on DRAM are more common now, so systems don't have to be so conservative with the refresh intervals.