Error Checking

Question 1

Parity bit how does it detect for errors?

Answer 1

A parity bit is set, even or odd.
After transmission, the amount of ones are counted and if it doesn’t follow the parity bit, we know there was an error during transmission.

Question 2

Why might parity bit not detect a transmission error?

Answer 2

If bits are interchanged, it won’t detect an error since the amount of ones would technically remain the same after transmission.

Question 3

Check sum what is it?

Answer 3

An additional piece of data added onto the data being transmitted which is also derived from that data.

Question 4

What is check digit?

Answer 4

An extra digit added to the end of some numeric data. It is calculated from the other digits in a way that can be replicated, which allows it to be checked after transmission.

Question 5

Echo check steps

Answer 5

• Data is transmitted from A to B
• B transmits a copy of the received data back to A
• A checks data received matches original data sent
• If data matches, A sends acknowledgement to B
• If data does not match, A resends original data