01-02-2012, 02:46 PM
Cryptography simple report
[attachment=16985]
Main sources
Network Security Essential / Stallings
Applied Cryptography / Schneier
Handbook of Applied Cryptography / Menezes, van
Oorschot, Vanstone
Innovative Cryptography, N. Moldovyan , A.Moldovyan
Modern Cryptography: Theory and Practice, Wenbo Mao
Steganography
.Steganography
Steganos = “covered” in Greek, Graphein = “to write”
.Being able to communicate secretly has always been
considered an advantage
Secret messages were often not written down, but rather
memorized by sworn messengers
.Or hidden
Demaratus, a Greek immigrant to Persia, reveals Persia’s
intention to attack Athens. Writes the secret message on a
tablet, and covers it with wax.
Histaiaeus encourages Aristagoras of Miletus to revolt
against the Persian King. Writes message on shaved head
of the messenger, and sends him after his hair grew
Chinese wrote on silk, turned into wax-covered ball that was
swallowed by the messenger
The classical cryptographic task is to provide for
a reversible transformation of an understandable
plaintext (original text) to a seemingly random
character sequence called a ciphertext or a
cryptogram.
The security of modern cryptosystems is not
based on the secrecy of the algorithm, but on
the secrecy of a relatively small amount of
information, called a secret key.
Applications of Cryptography
Protection against unauthorized reading (or providing information privacy)
Protection against creating false messages (both intentional and
unpremeditated)
Valid user authentication
Information integrity control
Information authentication
Digital signatures
Computerized secret voting
Digital cash
Computerized coin-tossing
Protection against the repudiation of the receipt of a message
Simultaneous contract signing
Protection against document forgery
[attachment=16985]
Main sources
Network Security Essential / Stallings
Applied Cryptography / Schneier
Handbook of Applied Cryptography / Menezes, van
Oorschot, Vanstone
Innovative Cryptography, N. Moldovyan , A.Moldovyan
Modern Cryptography: Theory and Practice, Wenbo Mao
Steganography
.Steganography
Steganos = “covered” in Greek, Graphein = “to write”
.Being able to communicate secretly has always been
considered an advantage
Secret messages were often not written down, but rather
memorized by sworn messengers
.Or hidden
Demaratus, a Greek immigrant to Persia, reveals Persia’s
intention to attack Athens. Writes the secret message on a
tablet, and covers it with wax.
Histaiaeus encourages Aristagoras of Miletus to revolt
against the Persian King. Writes message on shaved head
of the messenger, and sends him after his hair grew
Chinese wrote on silk, turned into wax-covered ball that was
swallowed by the messenger
The classical cryptographic task is to provide for
a reversible transformation of an understandable
plaintext (original text) to a seemingly random
character sequence called a ciphertext or a
cryptogram.
The security of modern cryptosystems is not
based on the secrecy of the algorithm, but on
the secrecy of a relatively small amount of
information, called a secret key.
Applications of Cryptography
Protection against unauthorized reading (or providing information privacy)
Protection against creating false messages (both intentional and
unpremeditated)
Valid user authentication
Information integrity control
Information authentication
Digital signatures
Computerized secret voting
Digital cash
Computerized coin-tossing
Protection against the repudiation of the receipt of a message
Simultaneous contract signing
Protection against document forgery