Answer the following questions:
1. Explain briefly how the following substitution ciphers can be broken: Caesar cipher, Simple substitution cipher, Vigenere cipher.
Answer
Caesar cipher can be broken through brute force. By simply running the possible shifts that the cipher could be executing, the message will come up eventually. Simple substitution can also be broken through brute force. This will take a long time though, so will cracking the Vigenere cipher unless you have a powerful computer that can quickly output possibilities.
2. Define symmetric encryption.
Answer
Symmetric encryption is an algorithm for cryptography that uses the same cryptographic keys for both the encryption of plaintext and decryption of ciphertext. The keys may be identical or there may be a simple transformation to go between the two keys.