What is the difference between Confusion and Diffusion in information security?

Confusion

Confusion defines making the relationship between the key and the cipher as difficult and as included as possible. In other words, the technique provides that the ciphertext provides no clue about the plaintext.

In this regard, the relationship between the data of the cipher text and the value of the encryption has to remain as difficult as applicable. It is completed by spreading out the single plaintext digit over several Ciphertext digits, including when a single bit of the plaintext is changed.

In confusion, it should influence the complete cipher text or change should appear on the complete cipher text and the relationship between the data of the ciphertext and the value of the encryption key is made difficult. It is achieved by substitution.

The main goal of confusion is to create it very complex to find the key even if one has most of the plaintext-ciphertext pairs produced with the similar key and in this regard, each bit of the Ciphertext should be based on the complete key and in several ways on multiple bits of the key, changing one bit of the key must change the Ciphertext completely.

Diffusion

Diffusion can define to the property that the repetition in the statistics of the plaintext is “dissipated” in the statistics of the Ciphertext. In diffusion, the output bits should be based on the input bits in a difficult way so that in case one bit of the plaintext is modified, thus the Ciphertext should change completely in an unstable or pseudorandom manner.

In diffusion, the statistical mechanism of the plaintext is used up into a high-range data of the ciphertext. This is achieved by having each plaintext digit influence the value of some ciphertext digits. Frequently, this is similar to having each ciphertext digit be influenced by some plaintext digits.

Let us see the comparison between Confusion and Diffusion.