Re: Encrypted Swap

Nicholas Knight (tegeran@home.com)
Fri, 17 Aug 2001 11:51:08 -0700


On Friday 17 August 2001 10:36 am, Adrian Cox wrote:
> Richard B. Johnson wrote:
> > ** At this instant, you just killed everything in RAM with precharge
> > **
>
> I've done a bit more reading. The documentation I have here suggests
> the precharge doesn't erase all of memory. Precharge copies from the
> sense amplifiers back into the current row. The erasure is a result of
> the sense amplifiers losing their contents faster than the memory
> cells, but even so only one of the 2^12 rows gets erased.

Now that we've established that SDRAM doesn't neccisarily get erased from
rebooting, does anyone know how long it takes for SDRAM to clear after
losing power? It seems to me that the fact that the RAM isn't neccisarily
wiped by the BIOS at boot is less important than wether or not shutting
down the system and having it shut down for 10 minutes causes the RAM to
be cleared so that any intruder/thief would be unable to get the
information neccisary to decrypt the swap...
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