21. In cryptography, what is cipher?

1. Encrypted message
2. Algorithm for performing encrption and decryption
3. Both (A) and (B)
4. Decrypted message

22. In public key encryption, if A wants to send an encrypted message

1. A encrypts message using B’s public key
2. A encrypts message using his private key
3. A encrypts message using B’s private key
4. A encrypts message using his public key

23. Symmetric-key cryptography started thousands of years ago when people needed to exchange

1. Files
2. Packets
3. Transmission
4. Secrets

24. Which of the following is not a type of symmetric-key cryptography technique?

1. Diffie hellman cipher
2. Caesar cipher
3. Data encryption standard (DES)
4. Playfair cipher

25. The man-in-the-middle attack can endanger the security of the Diffie-Hellman method if two parties are not

1. Joined
2. Authenticated
3. Submit
4. Separate

Software Engineering MCQ Questions and Answers

26.  In a/an ________ cipher, a pair of keys is used

1. Asymmetric-key
2. Symmetric-key
3. Both (A) and (B)
4. None of the above

27. Cryptanalysis is used

1. To increase the speed
2. To encrypt the data
3. To find some insecurity in a cryptographic scheme
4. To make new ciphers

28. In Cryptography, when text is treated at the bit level, each character is replaced by

1. 4 bits
2. 6 bits
3. 10 bits
4. 8 bits

29. Hashed message is signed by a sender using

1. His/her private key
2. His/her public key
3. Receiver’s public key
4. Receiver’s private key

30. The shift cipher is sometimes reffered to as a

1. Move cipher
2. Caesar cipher
3. Cipher
4. Cipher text