Cryptography
The course introduces the underlying the principles and design of cryptosystems. The course covers the basics concepts of cryptography including: traditional ciphers, block ciphers, stream ciphers, public and private key cryptosystems. The course also includes the theory of hash functions, authentication systems, network security protocols and malicious logic.
Tribhuvan University
Institute of Science and Technology
Cryptography Model Qn
Bachelor Level / fifth-semester / Science
Computer Science and Information Technology( CSC316 )
Cryptography
Full Marks: 60 + 20 + 20
Pass Marks: 24 + 8 + 8
Time: 3 Hours
Candidates are required to give their answers in their own words as far as practicable.
The figures in the margin indicate full marks.
SECTION A
Attempt any TWO question.
Define the CIA Triad and explain its components. List out the services of security. Differentiate between block ciphers and stream ciphers with examples.
Given p = 61, q = 53. Calculate the public key, private key, and encrypt the message “42”. Then, decrypt the ciphertext to retrieve the original message.
Explain the single round operation in DES. Describe the F function in DES.
SECTION B
Attempt any EIGHT question.
Explain the process of generating message digests using MD4.
Encrypt the message “INFORMATION” using the Playfair cipher with the keyword “SECURITY”.
Explain the concept of digital signatures and differentiate between direct and arbitrated digital signatures.
Define firewall and types of firewalls.
State Fermat’s theorem example. Write the algorithm forelse
Explain IP Security (IPSec) and its components.
Divide 3x2+x+6 by 5x + 3 over GF(9).
Explain the process of public key distribution and secret key distribution using public key cryptography.
Explain the concept of a denial of service attack and provide examples.