Overview & Definitions
Cryptography is a greek word which literally means “secret writing”. Cryptography refers to the art of transforming data and messages to make them secure and immune to attacks.
Cryptography can also be defined as the art of protecting information by transforming it (encrypting it) into an unreadable format, called cipher text. Only those who possess a secret key can decipher (or decrypt) the message into plain text.
In data and telecommunications, cryptography is necessary when communicating over any untrusted medium, which includes just about any network, particularly the Internet.
Primary Reason of Cryptography
Cryptography, then, not only protects data from theft or alteration but can also be used for user authentication. The initial unencrypted data is referred to as plaintext. It is encrypted into ciphertext, which will in turn (usually) be decrypted into usable plaintext. Cryptography is used mainly to achieve the Security Goals and protect them from Cryptographic Attacks.
- Data Integrity
Types Of Cryptography Algorithms
There are several ways of classifying cryptographic algorithms. But in general they are classified into three categories:-
- Secret or Shared Key Cryptography (SKC)
- Public Key Cryptography (PKC)
- Hash Functions