corresponding materials: lesson 1.1 - encryption algorithms discussion: confusion and diffusion are important properties of a secure cipher. confusion means that it is difficult to relate the key to the ciphertext, that the ciphertext should not reveal anything about the plaintext. diffusion means that the frequency of letter pairs, such as "th," in the plaintext is diffused over several characters in the ciphertext, thus making it difficult to decrypt through a letter frequency attack. in order for a cipher to be effective, it must possess both confusion and diffusion. exercise: read the following excerpt from the article "what is aes encryption and how does it work?". as you read, consider the following questions: 1. what are the parts or steps of the aes encryption algorithm? 2. what are the purposes of each of its parts or steps? 3. what are the complexities of the aes algorithm? how is it complicated in its parts and purposes, the relationship between the two, or in other ways?