Module 4 - Fundamentals of Network Communication

Practice Assessment - Error Control

Question 1 Given a 7-bit information frame (0, 1, 0, 1, 1, 0, 1), what is the even parity bit?

0

Question 2 Which of following statements are true for single-bit parity error detection?

It can detect all single bit errors in an information frame
It can detect all tripe bit errors in an information frame

Question 3 Which of following statements are true for two-dimensional parity error detection?

All of the above

Question 4 Assume bit errors occur at random. If each bit has 50% probability to be in error by transmission. What is the probability of a four-bit frame to be in error by transmission?

1/16

Question 5 What is the binary sequence that corresponds to polynomial code X^3 + x^2 + 1?

1101

Question 6 A cyclic code can be generated using __________.

Generator polynomial

Question 7 Which of the following is true for two-dimensional parity check

Arrange information in columns
More parity bit to improve coverage

Question 8 Polynomial codes are implemented using shift register circuits

True

Question 9 What is the binary equivalent of the following polynomial arithmetic x⁷ + x⁶ + x⁵ + x² + 1

11100101

Question 10 Using Euclidean Division, what will be the remainder of 70 by 999 where 70 is the divisor and 999 is the dividend

19

Graded Assessment - Error Control

Question 1 Given an information polynomial code I(x) = X^7 + x^6 + x^1 + 1, which is its corresponding per-bit information frame?

11000011

Question 2 What is the remainder obtained by dividing x^7 + x^5 + 1 by the generator polynomial x^3 + 1?

x^2 + x + 1

Question 3 Given a generator polynomial g(x) = x^3 + x + 1. Consider the information sequence 1001. By CRC method, what is the resulted codeword for transmission?

1001110

Question 4 Which of following generator polynomial can detect all single bit errors in an information frame?

g(x) = x + 1 

Question 5 Internet protocols use check bits to detect errors, instead of using CRC polynomial. The primary rationale is

Simplicity of implementation

Question 6 The two basic approaches in error control are error prevention and detection, and error correction and re-transmission

False

Question 7 Find parity bit for 1001011

0

Question 8 The divisor in a cyclic code is normally called the _________.

Generator

Question 9 The checksum of 0000 and 0000 is

1111

Question 10 In ASCII, a single parity bit code can detect ________ errors.

An odd number of