Cyclic Redundancy checking (CRC)循环冗余校验，又称多项式码。
在循环冗余校验中，不是通过将各比特位相加来得到期望的校验，而是通过在数据单元末尾加一串冗余比特，称作循环冗余校验码或循环冗余校验余数，使得整个数据单元可以被另一个预定的二进制数所整除(Cyclic, Redundancy, checking (CRC) cyclic redundancy check, also called polynomial code.In the cyclic redundancy check, not by checking each bit added to obtain the desired, but by the end of the data unit with a bunch of redundant bits, called cyclic redundancy checksum or cyclic redundancy check number, the data unit may be another predetermined number divisible by two hexadecimal)