# Basic CS-Networks [TCS Placement]: Sample Questions 116 - 117 of 133

Get unlimited access to the best preparation resource for competitive exams : get questions, notes, tests, video lectures and more- for all subjects of your exam.

## Question 116

Networks

### Explanation

- The cyclic redundancy check (CRC) detects errors in digital data using hash function.
- Used in digital networks and storage devices such as hard disk drives.
- Invented by W. Wesley Peterson in 1961 and further developed by the CCITT (Comite Consultatif International Telegraphique et Telephonique) .
- Quite simple to implement in hardware and can be easily analyzed mathematically.
- Based on binary division
- Also called polynomial code checksum.
- Given a k-bit frame or message, the transmitter generates an n-bit sequence, known as a
*frame check sequence (FCS)*, so that the resulting frame, consisting of (k + n) bits, is exactly divisible by some predetermined number. - The receiver then divides the incoming frame by the same number and, if there is no remainder, assumes that there was no error.

## Question 117

Networks

### Explanation

Bit rate | Baud rate |

Number of bits transmitted during one second | Number of signal units per second that are required to represent the bit send in one second. |

Determines the number of bits traveled per second. | Determines how many times the state of a signal is changing. |

Emphasis is on computer efficiency. | Data transmission over the channel is primary concerned. |

Cannot determine the bandwidth. | Can determine how much bandwidth is required to send the signal. |

Baud rate = |