Solution:

Error Detection:

When transmitting a bit stream over a transmission line or channel a scheme is normally incorporated into the transmission control circuit to enable the presence of bits or transmission error in the receiving block to be detected.

In general, this is done by the transmitter which computes a set of additional bits based on the contents of blocks of bits to be transmitted.

This is known as error detection which is based on a block of extra bits which is transmitted together with the original bits in the block.

The receiver uses the complete sets of received bits to determine whether the block contains any error to the high probability.

The different type of error detection scheme detects different type of errors. Also, the The number of bits used in some schemes determines the burst lengths that are detected.

The three most widely used schemes are parity, cyclic redundancy checks (CRC), and checksum.

Errors in the received frames are detected using a Parity Check and Cyclic Redundancy Check (CRC).

Parity Check:

A parity check is an error-correction process in network communication that ensures data transmissions between communication nodes are accurate.

In this process, the receiver agrees to use the same even parity bit or odd parity bit scheme as the sender.

Imagine a data transfer that looks like this: 1010001. This example has an odd number of 1s and an even number of 0s.

When an even parity checking is used, a parity bit with value 1 could be added to the data’s right side to make the number of 1s even -- and the transmission would look like this: 10100011.

If an odd parity check was used, the transmission would look like this: 10100010.

Cyclic Redundancy Check (CRC):

The cyclic redundancy check (CRC) is a technique used to detect errors in digital data. As a type of checksum, the CRC produces a fixed-length data set based on the build of a file or larger data set.

In terms of its use, CRC is a hash function that detects accidental changes to raw computer data commonly used in digital telecommunications networks and storage devices such as hard disk drives.