Cryptography introduction and its techniques

This presentation provides a clear explanation of cryptography and its techniques. It will also cover the various keys used in cryptography, the types of attacks that can occur, and explain hash functions with clear examples

1. CRYPTOGRAPHY SUBMITTED BY R.KARUNYA Aristo Programmers Team Mother Teresa Women’s University, Kodaikanal

2. INTERNET COMMUNICATION

3. WHAT IS CRYPTOGRAPHY? CRYPTO – HIDDEN/SECRET GRAPHY-WRITE Cryptography means secret writing. In cryptography the structure of the data is modified. cryptography uses mathematical algorithms to prevent data from unauthorized persons.

4. COMPONENTS Plaintext Original text. Ciphertext The encrypted, or unreadable, version of the plaintext information. Encryption algorithm  The mathematical algorithm that takes plaintext as the input and encrypts to ciphertext. It also produces the unique encryption key for that text. Decryption algorithm The mathematical algorithm that takes ciphertext as the input and decodes it into plaintext. It also uses the unique decryption key for that text. Encryption key The value known to the sender that is used to compute the ciphertext for the given plaintext. Decryption key.   The value known to the receiver that is used to decode the given ciphertext into plaintext.

5. CRYPTO SYSTEM

6. TYPES OF ATTACKS

7. KEYS

8. TYPES OF CRYPTOGRAPHY

9. SYMMETRIC ENCRYPTION

10. ASYMMETRIC ENCRYPTION

11. HASH FUNCTION A hash function is a mathematical function that converts a numerical input value into another compressed numerical value. It takes inputs of variable lengths to return output of a fixed lengths. APPLICATION: Password Hashing : A password is a secret series of character that one uses to gain access to a document, an application or a computer system.

12. CLASSICAL ENCRYPTION TECHNIQUES SUBSITUTION The identity changes while its position does not change. Simple process. Easy to crack the code. Unauthorized users can easily access the data. The time complexity of encryption and decryption is less. “JUMP” will be turned “MXPS” J K L M N O P Q R S T U V W X TRANSPOSITION It scrambles the character’s position. Complex process. Difficult to crack the code. Difficult for intruders to access the data. The time complexity of encryption and decryption is less.