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Entschlüsselt
Secret communication is a need not only for
military commanders and intelligence agents but
also of large commercial and industrial firm
relaying confidential information in to days
world probably at least ninety percent of
sensitive or secret information transmitted
electronically arises in the latter sector one
has only to think oft the flow of credit
information among various financial institutions
the tremendous quantities of such information
make it imperative that confidentiality be
guarantied by a system of encryption which is
both computationally feasible and yet very hard
to decrypt when information is intercepted
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Maria Stuart 1542-1587
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Zimmermann-Depeche im 1. Weltkrieg
Uneingeschränkter U-Bootkrieg
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Enigma 2. Weltkrieg
Al Turing1912-1954
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Einige Begriffe
Klartext (M) Chiffretext/Geheimtext (C) Schlüssel
(K) Klartextalphabet Geheimtextalphabet.
Verschlüsselung EK(M)C  Entschlüsselung
DK(C)M  Symmetrischer Algorithmus Public-Key-/As
ymmetrischer Algorithmus
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Für Profis auch nicht sicher
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Transposition
STAPILAOSLNMTIAESNNTDTEERINANKNFTSAPCOHSEIR
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ADFGVX-Teil 2
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