Introduction - Cryptology Unlocked - page 3

interfaces for a customer's cryptographic components, or they should at least
offer reproducible methods. But only a qualified customer can force vendors to
do this. This customer could be you, for example. The triumphant success of
the free PGP program shows one possible way toward 'cryptological justice'.

You will find reading this topic easier if you have some IT knowledge — people
who know the C programming language will have a home advantage — and if
you are not too hostile toward mathematics. But you don't have to be a profes-
sional programmer. Cryptology Unlocked is meant to be a book for practitioners
who want to get a rough idea of this fascinating field without having to delve
deeply into its theory. I'll spare you the nitty-gritty, like formulas, to the widest
possible extent. Many things can be explained verbally just as well. Sometimes,
however, there is no way around formulas. After all, cryptology is a field where
each side uses mathematical ingenuity to trick the other side. This is why not
everything can be explained without using some background knowledge. But
it's not a math book for sure.

You will find only a few ready-made programs on the Web site to this topic
( www.wileyeurope.com/go/cryptology ). Conversely, you will find plenty
of C source texts 'to play' with, and many documents that go far beyond the
things discussed here. The Web site to this topic, the list of references, and
information sources on the Internet will help you if you want to deal with
cryptology more deeply.

1.2 Why Busy Ourselves With Cryptology?

1.2.1 'I've Nothing to Hide'

I've heard this sentence over and again and think it's a big mistake. Almost
everybody is careful about their physical possessions: people lock their apart-
ment doors, don't leave their wallets lying around unattended, and lock their
cars. The fact that information represents an asset doesn't seem to have crossed
many people's minds. All right, you wouldn't write everything on postcards,
and you don't pass on the personal identification number (PIN) of your bank
card. But the problem begins when handling this PIN: people who write their
PIN on the card itself are simply unaware of the things unauthorized persons
can do with such information! Information often embodies a much greater value
than material things. Look at this example: back in the 1990s, Philip Morris
bought Kraft Foods for 12.9 billion dollars, including 1.3 billion for material
assets. The buyer deemed it worth paying 90 % for know-how, experienced
staff, brand name, customer base, and so on — all of this largely representing