PANIMALAR ENGINEERING COLLEGE

(An Autonomous Institution, Affiliated to Anna University Chennai)

QUESTION BANK
Details of the Course
Name of the Department :CSE
Name of the Course :CRYPTOGRAPHY AND NETWORK SECURITY
Course Code : 21CS1701
Semester :VII
Common To Programme(s) :-
Instructions
Blooms Level:Blooms Level 1 & 2 is Lower Order (LO) Cognitive type, Blooms Level 3 & 4 is
Intermediate Order Cognitive Type (IO) and Blooms Level 5 & 6 is Higher Order (HO) cognitive type.

2 Marks:For each unit five questions should be of lower order (LO) cognitive type and five
Questions should be of Intermediate order (IO) cognitive type.

13 /15 /16 Marks:For each Unit four questions should be of lower order (LO) cognitive type i.e.
remembrance type questions, five should be of intermediate order (IO) cognitive type i.e.
understanding type questions and One Question should be on Higher Order (HO) Application /
Design / Analysis / Evaluation / Creativity / Case study questions.
* HO Order is not applicable if the Question Pattern does not have Part C. In Such cases consider
HO as IO.
** If the Mark for Part B &C is less than the maximum mark of the Question, Sub Divisions shall be
added.
Course Outcome: (List the Course Outcomes of the Course)
CO1: Understand the fundamentals of network security, security architecture.
CO2: Apply the different cryptographic operations of symmetric cryptographic algorithms.
CO3: Apply the different cryptographic operations of public key cryptography.
CO4: Apply the various Authentication schemes to simulate different applications.
CO5: Understand various Security practices and System security standards.
CO6: Analyze various threats and vulnerabilities in systems.

Bloom’s Level: BL1 - Remembering, BL2 - Understanding, BL3 - Applying, BL4 - Analyzing, BL5–
Evaluating,BL6 - Creating.

Diagrams, Table Values, Equations must be legible and clear.

UNIT- I -INTRODUCTION
Bloom’s Course Marks
PART A ( 2 Marks)
Level Outcome Allotted
1. Compare passive and active attack. [BL2] [CO1] [2]

2. Why is asymmetric cryptography bad for huge data? Specify the [BL2] [CO1] [2]
reason.
3. Calculate the cipher text for the following using one time pad [BL2] [CO1] [2]
cipher. Plain text: ROCK & Keyword: BOTS.
4. What is avalanche effect? [BL3] [CO1] [2]
5. What is Cryptanalysis? [BL1] [CO1] [2]

Course Instructor Course Coordinator Head of the Department

Name & Designation Name & Designation
 6. Convert the given text “Anna University “into cipher text using rail [BL3] [CO1] [2]
fence technique?
7. What is avalanche effect? [BL1] [CO1] [2]
8. What is the main drawback of the One-Time Pad cipher? [BL2] [CO1] [2]
9. Distinguish between attack and threat. [BL3] [CO1] [2]
10. Define integrity and Non - repudiation? [BL3] [CO1] [2]

Descriptive Questions ( 13 /15/16 Marks)

1. Explain the OSI security architecture with an example? [BL2] [CO1] [13]
Describe the various security mechanisms.
2. Encrypt the following using play fair cipher using the keyword [BL3] [CO1] [13]
MONARCIIY."SWARAJ IS MY BIRTH RIGHT'. (Use X for blank
spaces)
3. Encrypt the message “ Pay more money” using hill cipher with [BL3] [CO1] [13]
the following key matrix.

4. Write a note on different types of Security Attacks and Services [BL2] [CO1] [13]
in Detail.
5. Elaborate on the following topics [BL3] [CO1] [13]
a. Perfect Security
b. Information Theory
c. Product Cryptosystem
6. What is mono alphabetic cipher/Examine how it differs from [BL4] [CO1] [13]
Cesar cipher.
7. Write a note on different types of Security Attacks and Services [BL2] [CO1] [13]
in Detail
8. Explain the substitution encryption techniques in detail? [BL3] [CO1] [13]

9. Explain the Transposition encryption techniques in detail? [BL3] [CO1] [13]

10. Encrypt and Decrypt the message “ Pay” using hill cipher with [BL6] [CO1] [15]
the following key matrix.

UNIT- II - SYMMETRIC KEY CRYPTOGRAPHY

Bloom’s Course Marks
PART A ( 2 Marks)
Level Outcome Allotted
1. Differentiate public key and conventional encryption? [BL1] [CO2] [2]

2. Find gcd (1970, 1066) using Euclid’s algorithm? [BL1] [CO2] [2]
3. Brief the strength of Triple DES [BL2] [CO2] [2]
4. Give the five modes of operations in block cipher. [BL2] [CO2] [2]
5. Difference between linear and differential cryptanalysis? [BL1] [CO2] [2]
6. Differentiate public key and conventional encryption [BL2] [CO2] [2]

Course Instructor Course Coordinator Head of the Department

Name & Designation Name & Designation
 7. Specify the applications of the public key cryptosystem? [BL2] [CO2] [2]
8. What are the disadvantages of double DES? [BL2] [CO2] [2]
9. List the uses of RC4. [BL2] [CO2] [2]
10. Define Modular exponentiation. [BL1] [CO2] [2]

Descriptive Questions ( 13 /15/16 Marks)

1. Apply the properties of Groups, Rings, and Fields to [BL3] [CO2] [13]
determine whether a given algebraic structure satisfies
the conditions of each.

2. Apply the steps of DES to demonstrate how data is transformed [BL3] [CO2] [13]
at each stage during encryption and decryption.

3. Analyze how AES handles key expansion and discuss its impact [BL4] [CO2] [13]
on the encryption process.
4. Apply the extended Euclidean algorithm to compute the [BL3] [CO2] [13]
GCD of 4864 and 3458
5. Evaluate the effectiveness of different block cipher modes of [BL5] [CO2] [13]
operation in securing data transmission over an insecure
network.
6. Analyze the structure and functioning of Blowfish rounds, and [BL4] [CO2] [13]
how they achieve confusion and diffusion
7. Analyze the impact of key distribution and algorithm choice on [BL4] [CO2] [13]
the overall effectiveness of the symmetric cipher model.
8. Evaluate the effectiveness of RC4 in terms of speed, simplicity, [BL5] [CO2] [13]
and susceptibility to cryptographic attacks
9. Evaluate the effectiveness of the SDES key generation process [BL5] [CO2] [13]
by computing K1 and K2 for the 10-bit key k = 1010000010
using the given P10 and P8 permutations.
10. Create a custom key expansion module for the AES algorithm [BL6] [CO2] [15]
that supports dynamic key sizes, and justify how your design
maintains the algorithm’s security requirements.

UNIT- III - PUBLIC KEY CRYPTOGRAPHY

Bloom’s Course Marks
PART A ( 2 Marks)
Level Outcome Allotted
1. Define replay attack [BL1] [CO3] [2]

2. Define Euler’s theorem and it’s application? [BL1] [CO3] [2]

3. What is Man in the Middle attack? [BL2] [CO3] [2]
4. Write the difference between public key and private key crypto [BL3] [CO3] [2]
systems?
5. List the Authentication requirements? [BL3] [CO3] [2]
6. What is the use of Fermat’s theorem? [BL2] [CO3] [2]

7. What is an elliptic curve? [BL1] [CO3] [2]

8. Mention any three Primality Testing Methods. [BL2] [CO3] [2]
9. Write the formula for Encryption and Decryption in RSA [BL3] [CO3] [2]

Course Instructor Course Coordinator Head of the Department

Name & Designation Name & Designation
 10. Define Euler’s totient function or phi function and their [BL2] [CO3] [2]
applications?

Descriptive Questions ( 13 /15/16 Marks)

1. State Chinese Remainder theorem and find X for the given set of [BL3] [CO3] [13]
congruent equations Using CRT.
X=2(mod 3)
X=3(mod 5)
X=2(mod 7)

2. Demonstrate Encryption and Decryption for the RSA algorithm [BL3] [CO3] [13]
parameters p=3, q=11, e=7, d=?, M=5
3. Users A and B use the Diffie-Hellman key exchange technique [BL4] [CO3] [13]
with a common prime q=71 and a primitive root a=7. If user A
has private key XA=5, what is A’s public key YA?.
4. Users Alice and Bob use the Diffie-Hellman key exchange [BL5] [CO3] [13]
technique with a common prime q = 83 and a primitive root=5.
a. If Alice has a private key Xa = 6, what is Alice's
public key?
b. If Bob has a private key Xs = 10, what is Bob's
public key?
c. What is the shared secret key?

5. Explain Elliptic Curve Cryptography encryption and decryption in [BL3] [CO3] [13]
detail.
6. Write short notes on Fermat’s theorem, Euler’s theorem and [BL2] [CO3] [13]
Chinese remainder theorem?

7. Find the secret key shared between user A & user B [BL5] [CO3] [13]
using Diffie Hellman algorithm for the following.
Q = 353, α (primitive root) = 3, XA = 45 & XB = 50
8. Consider the elliptic curve E11 (1, 6); that is the curve is defined [BL6] [CO3] [13]
by y2=x3+x+6with a module of P=11. Calculate all the points
inE11 (1, 6). Start by calculation by the right hand side of the
equation for all the values of n?
9. Find the primality test for the number 729 using Miller-Rabin [BL3] [CO3] [13]
Method.

10. State Chinese Remainder theorem and find X for the given set [BL5] [CO3] [15]
of congruent equations using CRT.
X=2(mod3)
X=1(mod5)
X=1(mod5)
X=3(mod9)
X=4(mod11)
UNIT- IV - MESSAGE AUTHENTICATION AND INTEGRITY
Bloom’s Course Marks
PART A ( 2 Marks)
Level Outcome Allotted
1. What are the functions used to produce an authenticator? [BL1] [CO4] [2]

2. What are birthday attacks? [BL1] [CO4] [2]

3. What do you mean by MAC? [BL2] [CO4] [2]

Course Instructor Course Coordinator Head of the Department

Name & Designation Name & Designation
 4. What is meant by Hash function? [BL3] [CO4] [2]
5. What is weak collision Resistance? [BL3] [CO4] [2]
6. What are the two approaches of digital signature? [BL2] [CO4] [2]

7. What is weak collision Resistance? [BL1] [CO4] [2]

8. What do you mean by one way property in hash function? [BL2] [CO4] [2]
9. Contrast various SHA algorithms. [BL1] [CO4] [2]
10. Define Kerberos. [BL2] [CO4] [2]

Descriptive Questions ( 13 /15/16 Marks)

1. Describe about hash functions? [BL3] [CO4] [13]
2. Illustrate about SHA algorithm and explain? [BL3] [CO4] [13]
3. Describe digital signature algorithm and show how signing and [BL4] [CO4] [13]
verification is done using DSS.
4. Elaborately explain Kerberos authentication mechanism with a [BL5] [CO4] [13]
suitable diagram
5. Explain briefly about X.509 certification mechanisms. [BL4] [CO4] [13]
6. i) Compare the uses of MAC and Hash function. Represent [BL2] [CO4] [13]
them using appropriate diagrams.
ii) List down the advantages of MD5 and SHA Algorithm
7. Explain Digital signature standard? [BL3] [CO4] [13]

8. Explain CMAC-HMAC algorithm in detail. [BL3] [CO4] [13]

9. What are the properties a hash function must satisfy? [BL3] [CO4] [13]
10. Explain briefly about the architecture and certification [BL5] [CO4] [15]
mechanisms in Kerberos andX.509.

UNIT- V - SECURITY PRACTICE AND SYSTEM SECURITY

Bloom’s Course Marks
PART A ( 2 Marks)
Level Outcome Allotted
1. Define S/MIME? [BL1] [CO5] [2]

2. Give the benefits of IP security? [BL1] [CO5] [2]

3. Differentiate Transport and Tunnel mode in IPsec? [BL2] [CO5] [2]
4. What are Zombies? [BL3] [CO6] [2]
5. What is an intruder? [BL3] [CO6] [2]
6. List the steps involved in SSL record protocol? [BL1] [CO5] [2]

7. What are the headers fields define in MIME? [BL2] [CO5] [2]
8. List the five principal services provided by PGP. [BL1] [CO5] [2]

Course Instructor Course Coordinator Head of the Department

Name & Designation Name & Designation
 9. Why E-mail compatibility function in PGP needed? [BL2] [CO5] [2]
10. List the limitations of SMTP/RFC 822? [BL1] [CO5] [2]

Descriptive Questions ( 13 /15/16 Marks)

1. Illustrate how PGP encryption is implemented through a suitable [BL3] [CO5] [13]
diagram
2. Explain S/MIME in detail. [BL2] [CO5] [13]

3. Explain the Architecture of IP security. [BL4] [CO5] [13]

4. Explain the characteristics and types of firewalls. [BL4] [CO6] [13]

5. Explain about SQL Injection in detail. [BL4] [CO6] [13]
6. Write short notes on Viruses & Firewalls. [BL3] [CO6] [13]
7. Define Intrusion Detection System (IDS). List all its types in [BL4] [CO6] [13]
detail with suitable diagram.
8. Explain the different types of cryptographic attacks and the [BL4] [CO6] [13]
countermeasures to prevent them
9. Explain details about web security. [BL2] [CO5] [13]
10. Evaluate the performance of PGP. Compare it with S/MIME. [BL5] [CO5] [15]

Course Instructor Course Coordinator Head of the Department

Name & Designation Name & Designation