Asymmetric key cryptography uses two keys: a public key and a private key. The public key can encrypt messages but only the private key can decrypt them. This allows for convenience, message authentication, detection of tampering, and non-repudiation. However, public keys need authentication, it is slower than symmetric key cryptography, uses more computer resources, a security compromise could affect many users, and loss of the private key would be irreparable.

1. Asymmetric
key

2. What is CRYPTOGRAPHY ?
• Cryptography is an art of protecting
information by transforming it
(encrypting it) in to an unreadable format
called cipher text. Only those who possess a
secret key can decipher (for decrypt) the
massage into plaintext.

3. ELEMENTS OF CRYPTOGRAPHY
• Plain text
• Cipher text
• Cipher
• Encryption
• Decryption

4. Encryption
Key 1
Decryption
Key 2
Plain text
Plain textCipher text
Cipher text

5. Cryptography algorithms are
divided into two groups and they
are:
• Symmetric key
• Asymmetric key

6. Asymmetric key
Two key:-
1) public key
2)private key

7. Advantages
 Convenience
 Provides for message authentication:
 Detection of tampering:
 Provide for non-repudiation:

8. Disadvantages
• Public keys should/must be authenticated:
• Slow:
• Uses up more computer resources:
• Widespread security compromise is
possible:
• Loss of private key may be irreparable: