Symmetric Asymmetric Substitution Transposition in Cryptography

In this class, We discuss Symmetric Asymmetric Substitution Transposition in Cryptography.

The reader should have prior knowledge of additive cipher. Click Here.

Symmetric Key Cryptography:

If the encryption and decryption use the same key, then we say it is symmetric key cryptography.

Asymmetric Key Cryptography:

If the encryption and decryption use different keys, then we say asymmetric key cryptography.

Substitution method:

Replacing a character in place of another character is called the substitution method.

The additive cipher uses the substitution method.

the character “h” is replaced with “w”

Transposition method:

Changing the positions of characters is called the transposition method.

Example:

“hello” is changed to “olhel”.