Patent ID: 7424111

Claim:
A system of applying parity bits to protect transmitting and receiving data, comprising: a transmitting-end device for transmitting data, including: a parity generator, which generates a parity bit in accordance with a data to be transmitted, wherein the data has a plurality of bits, a first parity location generator, which generates an inserting position N (positive integer) for the parity bit through a first function generator in accordance with a first key and a first counter, and a parity inserting unit, which inserts the parity bit in a position between (N−1)th- and Nth-bit of the data in accordance with the inserting position N generated by the first parity location generator, thereby generating an encrypted data; and a receiving-end device for receiving the data, including: a second parity location generator, which generates the inserting position N (positive integer) for the parity bit through a second function generator in accordance with a second key and a second counter, wherein the second key has the same value as the first key and the second counter is synchronous with the first counter, and a parity removing unit, which inputs the encrypted data and removes Nth bit of the encrypted data input in accordance with the inserting position N generated by the second parity location generator.