Explore topic-wise MCQs in Digital Communications.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Communications knowledge and support exam preparation. Choose a topic below to get started.

1.

EXAMPLES_OF_HASH_FUNCTIONS_ARE?$

A. MD5
B. SHA-1
C. MD5 & SHA-1
D. None of the mentioned
Answer» D. None of the mentioned
2.

WHICH_ALGORITHM_CAN_BE_USED_TO_SIGN_A_MESSAGE??$

A. Public key algorithm
B. Private key algorithm
C. Public & Private key algorithm
D. None of the mentioned
Answer» B. Private key algorithm
3.

A set of numbers is called as super increasing if$

A. Each element is greater than previous element
B. Each element greater than sum of all the previous elements
C. Each element greater than the average of all elements
D. Each element lesser than the sum of all the elements
Answer» C. Each element greater than the average of all elements
4.

A cryptographic hash function has variable output length.$

A. True
B. False
Answer» C.
5.

In this Merkle Hellman method same key is used for encryption and decryption.

A. True
B. False
Answer» C.
6.

Merkle hellman is a symmetric cryptosystem.

A. True
B. False
Answer» C.
7.

Knapsack problem can be solved by

A. Public key cryptosystem
B. Private key cryptosystem
C. Public & Private key cryptosystem
D. None of the mentioned
Answer» B. Private key cryptosystem
8.

Which has a key length of 128 bits?

A. IDEA
B. Triple-DES
C. IDEA & Triple-DES
D. None of the mentioned
Answer» B. Triple-DES
9.

Which are called the block ciphers?

A. IDEA
B. CAST
C. Triple-DES
D. All of the mentioned
Answer» E.
10.

Private key algorithm is used for _____ encryption and public key algorithm is used for _____ encryption.

A. Messages, session key
B. Session key, messages
C. Can be used for both
D. None of the mentioned
Answer» B. Session key, messages
11.

PGP system uses

A. Private key system
B. Public key system
C. Private & Public key system
D. None of the mentioned
Answer» D. None of the mentioned
12.

Pretty good privacy program is used for

A. Electronic mails
B. File encryption
C. Electronic mails & File encryption
D. None of the mentioned
Answer» D. None of the mentioned
13.

In a trapdoor function, the functions are easy to go in

A. One direction
B. Two directions
C. All directions
D. None of the mentioned
Answer» B. Two directions
14.

In public key cryptosystem which is kept as public?

A. Encryption keys
B. Decryption keys
C. Encryption & Decryption keys
D. None of the mentioned
Answer» B. Decryption keys
15.

In public key cryptosystem _____ keys are used for encryption and decryption.

A. Same
B. Different
C. Encryption Keys
D. None of the mentioned
Answer» C. Encryption Keys