The primary benefit of CRC is that it can detect more types of data errors than the other two methods.
Error detection at data link level is achieved by using a Frame Check Sequence (FCS) method like Parity, Checksum Calculation or Cyclic Redundancy Check (CRC).
CRC is used for this purpose. The control field is HEC (header error control).
CRC is a method of checking one constant or value repeatedly to get the accurate answer(trial and error method), where as in the check sum it is not like the trial and error,since the answer got in CRC is more accurate when compared to check sum
Each Ethernet frame contains a trailer with a cyclic redundancy check (CRC) of the frame contents. After reception of a frame, the receiving node creates a CRC from the bits in the frame to compare to the CRC value in the frame trailer. If these two CRC calculations match, the frame can be trusted as being received without error. The trusted frame will then be processed. A frame received with bad, nonmatching CRC's will be discarded.
The Ethernet (II) frame uses the Frame Check Sequence (FCS) field for error detection. This field is a 4-byte cyclic redundancy check (CRC) value that is calculated based on the frame's contents before transmission. When the frame is received, the receiving device calculates the CRC again and compares it to the FCS value; if they do not match, an error is detected, indicating that the frame may have been corrupted during transmission.
crc
(a) simple parity check (b) two-dimensional parity check (c) crc (d) checksum
Error correction mechanisms are techniques used in computer systems to detect and correct errors that may occur during data transmission or storage. These mechanisms typically involve adding redundant bits to the data to enable error detection and correction. Common error correction techniques include parity checks, checksums, and cyclic redundancy checks (CRC).
Advantages: CRC is simple to implement in binary hardware, Mathematical analysis of CRC is very simple, and it is good at detecting common errors caused by noise in transmission. Disadvantages: CRC is not suitable for protecting against intentional alteration of data, and overflow of data is possible in CRC.
cyclic redundancy check .A cyclic redundancy check (CRC) is an error-detecting code designed to detect accidental changes to raw computer data, and is commonly used in digital networks and storage devices such as hard disk drives.
to represent the frames sequence numberI believe this is wrong in the 5th edition....Network+ Guide to Networks on page57 it states that protocols in the data link layer add a header to the front of each packet and a trailer to the end of each packet to make frames. (The trailer indicates where a frame ends.)paragraph 4
A cyclic redundancy check error or CRC error occurs when the data verification value is a redundancy. This is used in detecting common errors caused by noise in transmission channels.