Ciphertext

The cipher is a part of cryptography. In the cipher, the original message, which is plaintext, is changed into a ciphertext with the use of an algorithm. The ciphertext is the secure form of the plaintext message with the help of using a cipher.

• Decryption: Decryption is the process of turning the ciphertext into the original message. In this process, a specific key is used for decoding the ciphertext.
• Encryption: Encryption is making a text unreadable to the outside of the specific group with an algorithm. This is the part of turning plaintext into ciphertext. The only people who have the key can solve the ciphertext.

Learn More: What is Cipher?

Methods for Creating Ciphertext

There are both classical and modern methods to applicate when transforming plaintext into ciphertext. Modern methods use computational power to create secure cipher for the users.

The classical methods consist of substitution cipher technique and transposition cipher technique. These methods complete themselves.

In the substitution cipher, only the characters of the ciphertext change. Their position remains the same. In contrast, characters change their positions in the transposition, but they are the same characters from plaintext.

There consists of two types of cryptography depending on the key of the ciphertext:

• Private key cryptography: The private key, also known as a symmetric key, uses only one key to decrypt and encrypt data. Since there is one key for both operations, it is faster than the public key cryptography. The key of the ciphertext is private because it has both functions.
• Public key cryptography: In public key cryptography, also known as asymmetric-key, there are two individual keys for decrypting and encrypting the message. It is slower compared to the private key. For encrypting the message public key is used. In contrast, a private key is required to decrypt the message. Everyone can use the public key. However, the private key is for the shared individuals only.