A computed value which depends on the contents of a block of data and which is transmitted or stored along with the data in order to detect corruption of the data. The receiving system recomputes the checksum based upon the received data and compares this value with the one sent with the data. If the two values are the same, the receiver has some confidence that the data was received correctly.
The checksum may be 8 bits (modulo 256 sum), 16, 32, or some other size. It is computed by summing the bytes or words of the data block ignoring overflow. The checksum may be negated so that the total of the data words plus the checksum is zero.
Internet packets use a 32-bit checksum.
See also digital signature, cyclic redundancy check.
- Check that
verb phrase Ignore that last remark; never mind: Salt and pepper. Check that
- Check the plumbing
verb phrase To go to the toilet; see a man about a dog (1940s+)
[chek-uhp] /ˈtʃɛkˌʌp/ noun 1. a comprehensive physical examination: He went to the doctor for a checkup. 2. an examination or close scrutiny, as for verification, accuracy, or comparison: They gave the motor a checkup. /ˈtʃɛkˌʌp/ noun 1. an examination to see if something is in order 2. (med) a medical examination, esp one taken at […]
noun 1. a valve permitting liquids or gases to flow in one direction only. noun 1. a valve that closes by fluid pressure to prevent return flow Also called nonreturn valve