ECES EXAM TOP POSSIBLE QUESTIONS AND CORRECT ANSWERS 2024

Which of the following is generally true about key sizes? a. Larger key sizes increase security b. Smaller key sizes increase security c. Key size is irrelevant to security d. Key sizes must be more than 256 bits to be secure - a. Larger key sizes increase security How did the ATBASH cipher work? a. By shifting each letter a certain number of spaces b. By Multi alphabet substitution c. By rotating text a given number of spaces d. By substituting each letter for the letter from the opposite end of the alphabet (i.e. A becomes Z, B becomes Y, etc.) - d. By substituting each letter for the letter from the opposite end of the alphabet (i.e. A becomes Z, B becomes Y, etc.) DES has a key space of what? a. 2^128 b. 2^192 c. 2^56 d. 2^64 - c. 2^56 Which of the following are valid key sizes for AES (choose three)? a. 56 b. 64 c. 128 d. 192 e. 256 f. 512 - c. 128 d. 192 e. 256 Which of the following algorithms uses three different keys to encrypt the plain text? a. AES b. 3DES c. Blowfish d. Skipjack - b. 3DES Which of the following is a block cipher? a. AES b. RC4 c. DH d. RSA - a. AES Which of the following is a type of encryption that has two different keys. One key can encrypt the message and the other key can only decrypt it? a. Symmetric b. Asymmetric c. Block cipher d. Stream cipher - b. Asymmetric