METHOD AND SYSTEM FOR PRODUCING AND CHECKING A HASH TOTAL FOR DIGITAL DATA GROUPED IN SEVERAL DATA SEGMENTS

摘要

The invention relates to methods and systems for producing a hash total and checking a hash total for digital data, said data being grouped into data segments. According to this method, a hash total is produced for each data segment. The individual hash totals are combined to form a first commutative hash total using a commutative link. In order to check the first commutative hash total, another hash total is produced for each data segment and these hash totals are combined to form a second commutative hash total using a commutative link. The first commutative hash total and the second commutative hash total are then checked to make sure that they coincide.