Monday, 12 March 2018

Cyclic Redundancy check

CRC (Cyclic Redundancy check)

CRC is error detecting technique which is used to detect an error occurred during transmission. CRC technique used in networking, cd, dvd and many other types of memory devices. CHKDSK check disk error using CRC algorithms to find any error. 

A pattern of 0s and 1s can be represented as a polynomial with coefficient of 0 and 1. The power of each term shows the value of the bit. 


  • Take Bit stream for transfer. 
  • Divide your bit stream with a divisor which used both sender and receiver. Divisor may have any bit stream 0 or 1 but used the same for both end. 
  • Divisor can also be represent using polynomial series as following rule.

  • Divide bit stream by selected divisor and apply remainder as CRC bit at the end of transmitted bit. 
  • On the receiver end received bits will be divided by divisor as used by sender. If remainder is zero then data is received correctly otherwise an error has been detected.