Cyclic Redundancy Check-


Cyclic Redundancy Check-




  •  Unlike checksum scheme, which is based on addition, CRC is based on binary division. 
  •  In CRC, a sequence of redundant bits, called cyclic redundancy check bits, are appended to the end of data unit so that the resulting data unit becomes exactly divisible by a second, predetermined binary number. 
  •  At the destination, the incoming data unit is divided by the same number. If at this step there is no remainder, the data unit is assumed to be correct and is therefore accepted.
  •  A remainder indicates that the data unit has been damaged in transit and therefore must be rejected

Hamming Code in Computer Network

Hamming code is an error-correcting code used to ensure data accuracy during transmission or storage. Hamming code detects and corrects the errors that can occur when the data is moved or stored from the sender to the receiver.

What is Redundant Bits?


Redundant bits are extra binary bits that are generated and added to the information-carrying bits of data transfer to ensure that no bits were lost during the data transfer. The number of redundant bits can be calculated using the following formula:

2r ≥ m + r + 1

where,

  • m is the number of bits in input data
  • r is the number of redundant bits.
















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