problem1. What sort of cryptographic attack made Double DES (2DES) not safe?
problem2. What is the chief hurdle preventing the widespread adoption of one-time pad cryptosystems to ensure data confidentiality?
problem3. Which Data Encryption Standard (DES) operating modes can be employed for large messages without the worry that an error early in the encryption or decryption process will spoil results during the communication? Describe your answer.
problem4. What are the major merits of symmetric encryption?
problem5. describe three demerits of symmetric encryption.