CRYPTOLOGY

MATHS

1. SOURASHTRA COLLEGE CRYPTOLOGY BY L.S.KARNAN II YEAR B.Sc., Maths

2. 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

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4. Encryption : c = E e ( p ) Decryption : p = D d ( 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:

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6. MATHS E ncryption NZGSH Decryption MATHS Example: Plain text Cipher text Plain text NZGSH Cipher text

7. 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 - versa A - 26 - Z T - 07 - G H - 19 - S S - 08 - H B.N F.L For Decryption For En cryption CODING METHOD :

8. Cryptography is the art and science of creating secret codes. Cryptanalysis is the art and science of breaking those code. CRYPTANALYSIS:

9. 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:

10. -Takes a long time to figure out the code. - It takes long to create the code . - OVERALL CRYPTOLOGY IT'S A LONG PROCESS . LIMITATIONS:

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