文档介绍：AStart
This book is about making information disappear. For somepeople,
this topic is a parlor trick, an amazing intellectual exercise that rattles
around about the foundations of knowledge. For others, the topic
has immense practical importance. An enemy can only control your
message if they can find it. If you hide data, you can protect your
thoughts from censorship and discovery.
The book describes a number of different techniques that people
can use to hide information. The sound files and images that float
about work today are great locations filled with possibilities.
Large messages can be hidden in the noise of these images or sound
files where no one can expect to find
image file can be used to hide information without any significant
change in the quality of the image.
Information can also be converted into something innocuous.
You can use the algorithmsfrom Chapter 7 to turn data into some-
thing entirely innocent like the voice-over to a baseball game. Bad
poetry is even easier to create.
If you want to broadcast information without revealing your lo-
cation, the algorithmsfrom Chapter 11 show how a group of peo-
ple municate without revealing who is talking. Completely
anonymous conversations can let people speak their mind without
endangering their lives.
The early chapters of the book are devoted to material that forms
the basic bag of tricks like private-key encryption, secret sharing,
and error-correcting codes. The later chapters describe how to apply
these techniques in various ways to hide information. Each of them
is designed to give you an introduction and enough information to
use the data if you want.
The informationineachchapterisroughlyarrangedinorder
of importance and difficulty. Each begins with a high-level sum-
mary for those who want to understand the concepts without wading
through technical details, and a introductory set of details, for those
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