Re: [dm-crypt] LUKS - SSD trim

[Arno Wagner <arno@wagner.name>]

On Sat, Apr 24, 2010 at 06:44:52PM +0200, Richard Zidlicky wrote:
[...]
> very offtopic, I would think there is certainly pressure from various
> agencies and companies not to erase anything. Given that printers are
> programmed to print secret identification patterns on every page there
> could be quite a few surprises lurking in copiers.

Only for color printers. It serves to identify a printer that was 
used in couterfiting currency. Storing everything in copiers is 
infeasible. Thstorage available is just about enough for the largest 
possible print-job, usually not more than 1000 or so different pages.
Given that this limit is routinely exceeded in a day, almost all
pages will not be stored.

> > That is way you use encryoption on top. However, it is higly unlikely
> > current HDDs/SSDs store a lot of information of this type. The storage
> > space is just not there.
> 
> most will do clever traffic analysis trying to predict access patterns at
> the very least.  Most likely not store everything to survive reboots but
> there can be exceptions.

Sorry, but I openend my SSD. There are just no bits in there for this.
My 30GB SSD has 2GB extra storage, most used for spares for broken
cells. The rest cannot store a lot. In addition, the SSD does not have a
clock that would be essential for adding timestamps to a data access
pattern log.

Here is a story from my country some years back. The federal prolice 
wanted to have all emails copied and archived. The ISPs responded
with the query where the cubic-meter of DAT tapes per day should
go? After this (and after realizing the cost, which the police would 
have had to pay), the proposal was off the table.

-- 
Arno Wagner, Dr. sc. techn., Dipl. Inform., CISSP -- Email: arno@wagner.name 
GnuPG:  ID: 1E25338F  FP: 0C30 5782 9D93 F785 E79C  0296 797F 6B50 1E25 338F
----
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