| 摘要 |
A system for reducing the size of data stored on a computer uses checksum algorithms to create a data entry in a computer readable medium. In operation, first and second checksums are applied to block of data. The results are combined with details of the algorithms used and at least one attribute of the data block to create a data entry. The attribute for the block may be a name, size, length, hash type amongst others. The data entry may be written in a markup language, preferably XML or SGML. The checksum values may be a hashed value, a digest or a checksum number. The checksum value may be generated by MD2, MD4, SHA, CRC, RIPE, CRC16, CRC32 or CRC64 algorithms. In a further embodiment a recovery system is provided. In use the data entry is received and checksum algorithms are applied to the data block, the results being compared to the checksum values in the data entry in order to identify candidate blocks for recovery. The checksum algorithms may be applied to the data blocks by either a linear or non linear scan. The non linear scan can be either a skipping, modulus or exponential scan. |
