Cryptography Reference
In-Depth Information
Atomic Funny
This signals super-duper funniness. The atomic bomb
of humor. Not to be confused with humor that just bombs. To
be used sparingly, no more than twice per episode.
21.2 Hiding in the Open
In the middle of Michael Crichton's
Jurassic Park
, when the charac-
ters are coming to realize the depth of their predicament, the math-
ematician in the bunch, Ian Malcolm, asks the dinosaur curators to
reprogram their computers. The original software began with an ex-
pected count of dinosaurs and then scanned the park looking to ac-
count for all of the dinosaurs on the list. If one was missing, it raised
an alarm and triggered a search. It all seemed bullet-proof.
But when Malcolm asked them to raise the expected count, the
computer came back and found even more dinosaurs than it did in
the original count.
“Now you see the flaw in your procedures,” Malcolm said. “You
only tracked the expected number of dinosaurs. You were worried
about losing animals, and your procedures were designed to advise
you instantly if you had less than the expected number. But that
wasn't the problem. The problem was, you had more than the ex-
pected number.”[Cri90]
The dinosaurs were breeding and the elaborate control system
couldn't account for them. Malcolm saw this weakness in the system
as an example of a larger truth about the universe.
“[S]traight linearity, which we have come to take for granted in
everything from physics to fiction, simply does not exist. Linearity
is an artificial way of viewing the world. Real life isn't a series of
interconnected events occurring one after another like beads strung
on a necklace. Life is actually a series of encounters in which one
event may change those that follow in a wholly unpredictable, even
devastating way.” he explained.
All data formats for computers begin with expectations. While
the formats may not be linear in the strictest sense of the word, they
are still well defined and the strength of this definition leads to its
weakness.
Much of this topic involves tweaking the actual data stored in a
file by introducing small changes like adding a bit more red to a pixel.
These solutions are useful, but they can introduce distortions that
can lead to detection. As Chapter 17 shows, many of the simplest al-
gorithms distort the statistical profile of the files in subtle but often
detectable ways. Tomake matters worse, the approach is in constant
competition with compression algorithms that try to squeeze out all
