Explain Redundancy check in short.

Introduction to Redundancy Check

Definition of Redundancy Check

Redundancy check is a method used in computer networks to check for errors that might have occurred during the transmission of data. It involves adding extra bits of data to the original data being sent, which helps in detecting errors when the data is received at the other end.

Importance of Redundancy Check in Data Communication

Redundancy check is crucial in data communication as it ensures the integrity of data during transmission. It helps in detecting errors that might occur due to various reasons such as noise, interference, or signal degradation during transmission.

Types of Redundancy Check

Parity Check

Explanation of Parity Check

Parity check is a simple form of error detecting code where an extra bit, known as a parity bit, is added to the data to make the total number of 1-bits either even (even parity) or odd (odd parity).

Example of Parity Check

For instance, consider the data bit sequence 1001101. In even parity check, the parity bit would be '1' to make the total number of 1-bits even. So, the transmitted data would be 10011011.

Formula used in Parity Check

There is no specific formula used in parity check. It is a simple count of the number of 1-bits in the data.

Checksum

Explanation of Checksum

Checksum is a method where the data is divided into equal segments, and the binary sum of these segments is calculated and sent along with the data.

Example of Checksum

For example, consider the data 1010101 and 1100110. The binary sum of these two segments is 10111011. This sum is sent along with the data.

Formula used in Checksum

The formula used in checksum is simple binary addition of the data segments.

Cyclic Redundancy Check (CRC)

Explanation of CRC

CRC is a more complex method of error detection where the data is divided by a predetermined divisor, and the remainder of this division is sent along with the data.

Example of CRC

For instance, consider the data 1010101 and the divisor 1101. The remainder of the division is 101, which is sent along with the data.

Formula used in CRC

The formula used in CRC is a simple binary division of the data by the divisor.

Detailed Process of Redundancy Check

Data Division

Explanation of Data Division

In redundancy check, the data is divided into equal segments. This division depends on the type of redundancy check being used.

Diagram showing Data Division

A diagram is not necessary for this part as it is a simple explanation of how data is divided.

Addition of Redundant Bits

Explanation of the Addition of Redundant Bits

Redundant bits are added to the data based on the type of redundancy check. In parity check, a parity bit is added. In checksum, the binary sum of the data segments is added. In CRC, the remainder of the division is added.

Diagram showing the Addition of Redundant Bits

A diagram is not necessary for this part as it is a simple explanation of how redundant bits are added.

Transmission of Data

Explanation of the Transmission of Data

The data, along with the redundant bits, is then transmitted over the network.

Diagram showing the Transmission of Data

A diagram is not necessary for this part as it is a simple explanation of how data is transmitted.

Checking at Receiver's End

Explanation of the Checking at Receiver's End

At the receiver's end, the received data is checked for errors using the redundant bits. If the check reveals an error, the data is requested again.

Diagram showing the Checking at Receiver's End

A diagram is not necessary for this part as it is a simple explanation of how data is checked at the receiver's end.

Importance of Redundancy Check in Error Detection

Explanation of how Redundancy Check helps in Error Detection

Redundancy check helps in error detection by adding extra bits of data to the original data. These extra bits help in detecting if any error has occurred during transmission.

Example showing the role of Redundancy Check in Error Detection

For instance, in parity check, if the received data has an odd number of 1-bits in even parity check, it indicates that an error has occurred during transmission.

Conclusion

Recap of the importance and process of Redundancy Check

Redundancy check is a crucial method used in data communication to ensure the integrity of data during transmission. It involves adding extra bits of data to the original data, which helps in detecting errors when the data is received at the other end.

Final thoughts on the role of Redundancy Check in Data Communication

In conclusion, redundancy check plays a vital role in data communication. It not only ensures the integrity of data but also helps in maintaining the reliability of the communication system.

Summary

Redundancy check is a method used in computer networks to check for errors that might have occurred during the transmission of data. It involves adding extra bits of data to the original data being sent, which helps in detecting errors when the data is received at the other end. There are three types of redundancy check: parity check, checksum, and cyclic redundancy check (CRC). Parity check involves adding a parity bit to make the total number of 1-bits either even or odd. Checksum involves dividing the data into segments and calculating the binary sum of these segments. CRC involves dividing the data by a predetermined divisor and sending the remainder of the division along with the data. The process of redundancy check includes data division, addition of redundant bits, transmission of data, and checking at the receiver's end. Redundancy check is important in error detection as it helps in detecting errors that might occur due to noise, interference, or signal degradation during transmission.

Analogy

Redundancy check is like adding an extra layer of protection to a package before sending it through the mail. Just like the extra layer helps in detecting any damage or tampering during transit, redundancy check helps in detecting errors that might have occurred during the transmission of data.