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I'm reminded of the "I can't send email to anyone over 100 miles away" story. There is, of course, a perfectly rational explanation... but that doesn't change t

I'm reminded of the "I can't send email to anyone over 100 miles away" story. There is, of course, a perfectly rational explanation... but that doesn't change the spooky arbitrariness of it.. EDIT: Not sure why I forgot to link this, out of one of my all-time favorite presentations. I give you: The Mechanical Transmogrification of Diodes into Capacitors! https://c3.ndc.nasa.gov/dashlink/static/media/other/ObservedFailures4.html https://c3.ndc.nasa.gov/dashlink/static/media/other/Observed...

pfarrell 4y ago
For those that haven't see it yet. https://www.ibiblio.org/harris/500milemail.html https://www.ibiblio.org/harris/500milemail.html
- grantonthenet 4y ago
  That was a fun read
deathanatos 4y ago
And the "more magic" switch: http://www.catb.org/jargon/html/magic-story.html http://www.catb.org/jargon/html/magic-story.html
- yellowapple 4y ago
  And Tom Knight and the Lisp Machine: http://www.catb.org/jargon/html/koans.html#id3141171 http://www.catb.org/jargon/html/koans.html#id3141171 > A novice was trying to fix a broken Lisp machine by turning the power off and on. > Knight, seeing what the student was doing, spoke sternly: “You cannot fix a machine by just power-cycling it with no understanding of what is going wrong.” > Knight turned the machine off and on. > The machine worked.
hinkley 4y ago
I've mentioned before how loud an argument we got into with a guy who aspired to being a hacker, and yet didn't understand that the magnetic domains on a HDD were essentially analog. Even after we asked him why, if hard drives were truly binary, that secure disk erase tools were so complex and slow he still insisted that everything was binary, soup to nuts. Even the simplest things are a fiction. Or maybe I should say especially the simplest things are a fiction.
- coldtea 4y ago
  >Even after we asked him why, if hard drives were truly binary, that secure disk erase tools were so complex and slow he still insisted that everything was binary Well, the argument was bad though: whether hard drives are analog is orthogonal to why "secure disk erase tools are so complex and slow". I see what you meant ("if they were digital you could just tell them to flip to zero and that would be easy and fast"). Sure, but there are many other reasons why secure disk erase tools could be complex and slow even in an imagined all-digital disk (and of course the imaginary digital substrate operations could just be a slow tech, the way RAM is slower than Lx caches, etc.). And while for delete you just need to change some directory entries to mark as none, for "secure erase" you'd also want to "reset" every bit, so at least similar time to the work you do when you write a file of same size.
- charcircuit 4y ago
  >that secure disk erase tools were so complex It's security theater. All you have to do is write 0s to the entire HDD.
  - yellowapple 4y ago
    It depends on the value of your data. It's theoretically possible to use specialized equipment to find remnants of the data even after having been zero'd out (by taking out the platters and very carefully poring over the ever-so-slight analog-induced discrepancies in what "0" and "1" look like), but unless your attacker is the NSA you probably don't have to worry about that (and if your attacker is the NSA, you're probably already using full-disk encryption anyway, which largely renders disk erasure a moot point).
    - charcircuit 4y ago
      >It's theoretically possible to use specialized equipment to find remnants of the data even after having been zero'd out No, this is not possible neither in theory nor in practice. >by taking out the platters and very carefully poring over the ever-so-slight analog-induced discrepancies in what "0" and "1" look like Even doing this is not enough to recover the data. What 0 and 1 look like isn't even constant. There is variability in what the current value is set to and their is variability in what the previous value was set to. There is too much randomness to recover the original data. >which largely renders disk erasure a moot point Disk erasure in this case can still be useful. In this case you only have to overwrite the master key. The idea that overwritten data can be recovered is an urban legend that is not based off reality, and simply wastes people's time and contributes to ewaste from people destroying harddrives. For just wiping data overwriting it with anything is fine. If you plan on using the disk for FDE you should overwrite the drive with random bytes so that you don't leak the size of the used disk space.

pfarrell 4y ago

For those that haven't see it yet. https://www.ibiblio.org/harris/500milemail.html https://www.ibiblio.org/harris/500milemail.html

grantonthenet 4y ago
That was a fun read

deathanatos 4y ago

And the "more magic" switch: http://www.catb.org/jargon/html/magic-story.html http://www.catb.org/jargon/html/magic-story.html

yellowapple 4y ago
And Tom Knight and the Lisp Machine: http://www.catb.org/jargon/html/koans.html#id3141171 http://www.catb.org/jargon/html/koans.html#id3141171 > A novice was trying to fix a broken Lisp machine by turning the power off and on. > Knight, seeing what the student was doing, spoke sternly: “You cannot fix a machine by just power-cycling it with no understanding of what is going wrong.” > Knight turned the machine off and on. > The machine worked.

hinkley 4y ago

I've mentioned before how loud an argument we got into with a guy who aspired to being a hacker, and yet didn't understand that the magnetic domains on a HDD were essentially analog. Even after we asked him why, if hard drives were truly binary, that secure disk erase tools were so complex and slow he still insisted that everything was binary, soup to nuts. Even the simplest things are a fiction. Or maybe I should say especially the simplest things are a fiction.

coldtea 4y ago
>Even after we asked him why, if hard drives were truly binary, that secure disk erase tools were so complex and slow he still insisted that everything was binary Well, the argument was bad though: whether hard drives are analog is orthogonal to why "secure disk erase tools are so complex and slow". I see what you meant ("if they were digital you could just tell them to flip to zero and that would be easy and fast"). Sure, but there are many other reasons why secure disk erase tools could be complex and slow even in an imagined all-digital disk (and of course the imaginary digital substrate operations could just be a slow tech, the way RAM is slower than Lx caches, etc.). And while for delete you just need to change some directory entries to mark as none, for "secure erase" you'd also want to "reset" every bit, so at least similar time to the work you do when you write a file of same size.
charcircuit 4y ago
>that secure disk erase tools were so complex It's security theater. All you have to do is write 0s to the entire HDD.
- yellowapple 4y ago
  It depends on the value of your data. It's theoretically possible to use specialized equipment to find remnants of the data even after having been zero'd out (by taking out the platters and very carefully poring over the ever-so-slight analog-induced discrepancies in what "0" and "1" look like), but unless your attacker is the NSA you probably don't have to worry about that (and if your attacker is the NSA, you're probably already using full-disk encryption anyway, which largely renders disk erasure a moot point).
  - charcircuit 4y ago
    >It's theoretically possible to use specialized equipment to find remnants of the data even after having been zero'd out No, this is not possible neither in theory nor in practice. >by taking out the platters and very carefully poring over the ever-so-slight analog-induced discrepancies in what "0" and "1" look like Even doing this is not enough to recover the data. What 0 and 1 look like isn't even constant. There is variability in what the current value is set to and their is variability in what the previous value was set to. There is too much randomness to recover the original data. >which largely renders disk erasure a moot point Disk erasure in this case can still be useful. In this case you only have to overwrite the master key. The idea that overwritten data can be recovered is an urban legend that is not based off reality, and simply wastes people's time and contributes to ewaste from people destroying harddrives. For just wiping data overwriting it with anything is fine. If you plan on using the disk for FDE you should overwrite the drive with random bytes so that you don't leak the size of the used disk space.