Cyclic Redundancy Code. A small integer value computed from a sequence of octets used to detect errors that result when the sequence of octets is transmitted from one machine to another. Typically, packet switching network hardware computes a CRC and appends it to a packet when transmitting. Upon reception, the hardware verifies the contents of the packet by recomputing the CRC and comparing it to the value sent. A CRC detects more errors that a checksum that uses additive methods. Basically, the errors occur when the calculation does not pass, indicating corrupted data.