CYBER SECURITY :CRYPTOGRAPHY

CRYPTOGRAPHY

Crypto means Secret and Graphy means writing so cryptography means secret-writing 

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Cryptography is an art of transforming Plain-text (meaningful message) into Cipher-text (not meaningful message) and then re-transforming that message back to protect it from third party that can be hacker, cracker anyone.

As it is possible that encrypted message can sometimes be broken by Crypt-analysis, on the other hand cryptography techniques are virtually unbreakable. 

Some Basic concepts which are useful for Cryptography are:-

1. Cryptanalysis - Code-breaking but without knowledge of key.
2. Cipher - An Algo used to transform plain-text to cipher-text by transposition or substitution.
3. Key - Secret information known to the sender and receiver only.
4. Encode - Process of converting plain-text to cipher-text.
5. Decode - Process of converting cipher-text to plain-text.
6. Cryptology - Cryptography + Cryptanalysis.

As the use of Internet and other forms of electronic communication becoming handy day-by-day so the security of such communication is also becoming more important. Cryptography is used to protect e-mails, credit card information bank transactions corporate data governmental information. one of the most popular cryptography system used on the internet is Pretty Good Privacy because of its effectiveness.

Modern Cryptography concerns with following main objectives :-

• Authentication of legitimate entities 

• Confidentiality

• Integrity

• Non Repudiation(denial of service)