Q3. Discuss the concept of redundancy in error detection and correction.
Ans- Error Detection and Correction:- In error detection, we are looking only
to see if any error has occurred or not. But in error correction, we need to know
the exact number of bits that are corrupted and their location in the message. The
number of the errors and the size of the message are important factors.
Concept of Redundancy in Error Detection and Correction:-
The central concept in detecting or correcting errors is redundancy. To be able to
detect or correct errors, we need to send some extra bits with our data. These
redundant bits are added by the sender and removed by the receiver. Their
presence allows the receiver to detect or correct corrupted bits. The concept of
including extra information in the transmission for error detection is a good one.
But instead of repeating the entire data stream, a shorter group of bits may be
appended to the end of each unit. This technique is called redundancy because
the extra bits are redundant to the information: they are discarded as soon as the
accuracy of the transmission has been determined. : Redundancy is achieved
through coding schemes. The sender adds redundant bits through a process that
creates a relationship between the redundant bits and the actual data bits. The
receiver checks the relationships between the two sets of bits to detect or correct
the errors.
