SOURASHTRA COLLEGE CRYPTOLOGY BY L.S.KARNAN
Cryptology is the Study of ‘’Secret Writings’’. Modern Cryptology combines the studies of Computer
Science and Mathematics for the purpose of Encoding information to ensure that data is secure.
It comes from the Greek words Kryptos, meaning hidden and Graphen, meaning to write.
Invisible ink is a good example.
CRYPTOLOGY
Encryption: c = Ee(p)
Decryption: p = Dd(c)
Here p is a block of plaintext,
c is a block of ciphertext,
E is the encryption function, e is the encryption key,
D is the decryption function and d is the decryption key.
CRYPTOGRAPHY:
A B C D E……………Y Z
26 25 24 23 22…………... 2 1
1 2 3 4 5……………25 26 FORWARD NUMBER
FORWARD LETTER
BACKWARD NUMBER
M - 14 - N vice - versaA - 26 - ZT - 07 - GH - 19 - SS - 08 - H
B.N F.L
For DecryptionFor Encryption
CODING METHOD :
Cryptography is the art and
science of creating secret
codes.
Cryptanalysis is the art and
science of breaking those
code.
CRYPTANALYSIS:
1.Now-a-days, internet is very insecure therefore cryptology method is followed to safeguard to transmit data.
2.It is used in ATM centre.
3.It is used in World War-II
USES:
-Takes a long time to figure out the code.
-It takes long to create the code.
-OVERALL CRYPTOLOGY IT'S A LONG PROCESS.
LIMITATIONS: