| 摘要 |
<p>This invention concerns the checking of data in a systems where the security is an important issue. According to the invention a first reference value is calculated at least partly based on a first error check value calculated from the data and a first authentication value (202). When checking the data a second error check value is calculated from the data. As well, a second reference value is calculated at least partly based on a first and a second value from the set of the second error check value, a second authentication value and the first reference value. The second reference value is compared with a third value from the set of the second error check value, the second authentication value and the first reference value. The invention also comprises a transmitter and a receiver which are arranged to perform the described operations.</p> |
