Symmetric Encryption

  • Symmetric encryption is the oldest and best-known technique.
  • A secret key, which can be a number, a word, or just a string of random letters, is applied to the text of a message to change the content in a particular way.This might be as simple as shifting each letter by a number of places in the alphabet.
  • Symmetric encryption uses the identical key to both encrypt and decrypt the data. 
  • As long as both sender and recipient know the secret key, they can encrypt and decrypt all messages that use this key.

Examples of Symmetric Encryption includes: DES, Triple-DES (3DES), IDEA, CAST5, BLOWFISH, TWOFISH.

Asymmetric Encryption

  • This encryption technique is born from the disadvantage of Symmetric Encryption.
  • Asymmetric encryption, in which there are two related keys–a key pair(A public Key and a Private Key). 
  • A public key is made freely available to anyone who might want to send you a message. A second, private key is kept secret, so that only you know it. 
  • Any message (text, binary files, or documents) that are encrypted by using the public key can only be decrypted by applying the same algorithm, but by using the matching private key. 
  • Any message that is encrypted by using the private key can only be decrypted by using the matching public key.

Examples of Asymmetric Encryption includes: RSA, DSA.