# NPTEL Cryptography And Network Security Assignment 4 Answers 2022

Cryptography And Network Security Assignment 4 Answers 2022:- In this post, We have provided answers of NPTEL Cryptography And Network Security Assignment 4 . We provided answers here only for reference. Plz, do your assignment at your own knowledge.

## About Cryptography And Network Security

The aim of this course is to introduce the student to the areas of cryptography and cryptanalysis. This course develops a basic understanding of the algorithms used to protect users online and to understand some of the design choices behind these algorithms. Our aim is to develop a workable knowledge of the mathematics used in cryptology in this course. The course emphasizes giving a basic understanding of previous attacks on cryptosystems with the aim of preventing future attacks. A wide variety of basic cryptographic primitives will be discussed along with recent developments in some advanced topics like identity-based encryption, attribute-based encryption, functional encryption, two-party/multi-party computation, bitcoin and crypto-currency and postquantum cryptography. The cryptanalysis part will help us understand challenges for cybersecurity that includes network security, data security, mobile security, cloud security and endpoint security.

CRITERIA TO GET A CERTIFICATE

Average assignment score = 25% of the average of the best 8 assignments out of the total 12 assignments given in the course.
Exam score = 75% of the proctored certification exam score out of 100

Final score = Average assignment score + Exam score

YOU WILL BE ELIGIBLE FOR A CERTIFICATE ONLY IF AVERAGE ASSIGNMENT SCORE >=10/25 AND EXAM SCORE >= 30/75. If one of the 2 criteria is not met, you will not get the certificate even if the Final score >= 40/100.

## Cryptography And Network Security Assignment 4 Answers 2022

1. x3+x+1 over R is a ………

(a) reducible polynomial
(b) irreducible polynomial
(c) both(a) and (b)
(d) neither (a) nor (b)

`Answer:- b`

2. Let f{x)= 2x2+3x+3 and g(x) = 3x2+2x+1. Then the degree of f(x) + g{x) over Z5 is

(a) 3
(b) 2
(c) 1
(d) 0

`Answer:- b`

3. What is the remainder when 3444 + 4333 is divided by 5?

(a) 0
(b) 1
(c) 2
(d) 3

`Answer:- a`

4. If p is an odd prime, then there are ……. quadratic residues.

(a) p
(b) p-1
(c) (p-1)/2
(d) (p+1)/2

`Answer:- c`

5. The quadratic residues mod 11 are ….

(a) 1,3,4,5,9
(b) 1,2,3,4
(c) 1,3,5,7,8,9
(d) None of these

`Answer:- a`

6. What is the remainder when 666 is divided by 7?

(a) 1
(b) 2
(c) 4
(d) 6

`Answer:- a`

7. Let p = 8 and q = 19. Then ó(Pg)= ..

(a) 70
(b) 57
(c) 38
(d) 72

`Answer:- d`

8. Last digit of 32022 …

(a) 3
(b) 5
(c) 7
(d) 9

`Answer:- d`

9. If ged(a, n) = 1, then aon) = 1 (mod n), where o(n) is Euler’s totient function. The above statement is ..

(a) True
(b) False

`Answer:- a`

10. Let f(x) = 3x3 +2x +1 and g(x) = x2+4x +1. Then the degree of f(x) * g(x) over Zs is

(a) 3
(b) 2
(c) 4
(d) 5

`Answer:- d`

COURSE LAYOUT

• Week 1: Introduction to cryptography, Classical Cryptosystem, Block Cipher.
• Week 2: Data Encryption Standard (DES), Triple DES, Modes of Operation, Stream Cipher.
• Week 3: LFSR based Stream Cipher, Mathematical background, Abstract algebra, Number Theory.
• Week 4: Modular Inverse, Extended Euclid Algorithm, Fermat’s Little Theorem, Euler Phi-Function, Euler’s theorem.
• Week 5: Advanced Encryption Standard (AES), Introduction to Public Key Cryptosystem, Diffie-Hellman Key Exchange, Knapsack Cryptosystem, RSA Cryptosystem.
• Week 6: Primarily Testing, ElGamal Cryptosystem, Elliptic Curve over the Reals, Elliptic curve Modulo a Prime.
• Week 7: Generalized ElGamal Public Key Cryptosystem, Rabin Cryptosystem.
• Week 8 : Message Authentication, Digital Signature, Key Management, Key Exchange, Hash Function.
• Week 9 : Cryptographic Hash Function, Secure Hash Algorithm (SHA), Digital Signature Standard (DSS).
• Week 10: Cryptanalysis, Time-Memory Trade-off Attack, Differential and Linear Cryptanalysis.
• Week 11: Cryptanalysis on Stream Cipher, Modern Stream Ciphers, Shamir’s secret sharing and BE, Identity-based Encryption (IBE), Attribute-based Encryption (ABE).
• Week 12: Side-channel attack, The Secure Sockets Layer (SSL), Pretty Good Privacy (PGP), Introduction to Quantum Cryptography, Blockchain, Bitcoin and Cryptocurrency.