Tiny whiskers make huge memory storage

2003-02-04 Thread Sunder
http://www.upi.com/print.cfm?StoryID=20030131-020248-9059r


Tiny whiskers make huge memory storage

UPI Science News
From the Science  Technology Desk
Published 1/31/2003 4:07 PM

BUFFALO, N.Y., Jan. 31 (UPI) -- New, tiny magnetic sensors could help
break a technical barrier to ushering in the next generation of computer
disk storage capacity, researchers reported Friday.

The sensors, filaments of nickel thinner than a wavelength of visible
light, are capable of detecting extremely weak magnetic fields.
SNIP


Yeah, yeah, yeah, lots of hype about storing terabytes and so on, not
worried about that at all.  The real question now is this: how effective
are these nickel whiskers are recovering erased data off existing
platters, or more precisely how many times do we need to overwrite a disk
now to wipe the data?

The Guttman technique is what, overwrite something 37x with various
patterns and random numbers, so how does this discovery change this
number?

Yes, yes, we've all discussed to death that the best way to wipe a hard
disk is to melt it down in a furnace, scatter the ashes in the ocean,
etc... but what if you want to reuse it?  (The 2nd obvious parallel is to
encrypt everything ahead of time too... also discussed to death, see the
archives, yadda, yadda)

My question is what's a reasonable order of magnitude of overwriting data
now, assuming you're not trying to hide data from, say the NSA.


--Kaos-Keraunos-Kybernetos---
 + ^ + :NSA got $20Bil/year |Passwords are like underwear. You don't /|\
  \|/  :and didn't stop 9-11|share them, you don't hang them on your/\|/\
--*--:Instead of rewarding|monitor, or under your keyboard, you   \/|\/
  /|\  :their failures, we  |don't email them, or put them on a web  \|/
 + v + :should get refunds! |site, and you must change them very often.
[EMAIL PROTECTED] http://www.sunder.net 




RE: Tiny whiskers make huge memory storage

2003-02-04 Thread Trei, Peter
 Sunder[SMTP:[EMAIL PROTECTED]] writes
[..]
 Yeah, yeah, yeah, lots of hype about storing terabytes and so on, not
 worried about that at all.  The real question now is this: how effective
 are these nickel whiskers are recovering erased data off existing
 platters, or more precisely how many times do we need to overwrite a disk
 now to wipe the data?
  [...]

Each time a more sensitive detector is discoverd, it's used  by
disk manufacturers to increase storage density. The tracks get finer,
the bits and the magnetic forces they generate smaller. I expect this at 
least partially cancels out the advantage that a more sensitive detector 
gives the spy.

Of course, some sensitive techniques (SQUIDs, etal) are not economic for
casual use.

Peter