Error Detection and Correction

Question 1

Evaluate the use of parity bits in detecting transmission errors

Answer 1

∆ If an odd number have flipped am error will have been detected but the number of errors will not be detected
∆ If an even number of bits has flipped the error will not be detected

Question 2

Describe echo checking as a method of detecting data transmission errors

Answer 2

∆ The receiving device sends the data back to the transmitting device
∆ The transmitting device compares the data with the original data
∆ The transmitting device retransmits the data if there was an error

Question 3

01101010 includes a parity bit an error occurs when this byte is transmitted and is received as 01101110 describe how this error occurred and explain the consequences if the byte is received as 00001010

Answer 3

∆ Even parity is being used, the received bytes parity is odd
∆ The double error will not be detected as the bytes parity is still even.