Abstract: Methods and apparatus for performing adaptive compression are disclosed. A data stream is divided into a plurality of data segments. When one of the plurality of data segments is compressed, it is determined whether the compression has been successful. When the compression has been successful, a data segment in proximity to the compressed segment (e.g., the next data segment in the plurality of data segments) is compressed. However, when the compression has been unsuccessful, one or more of the plurality of data segments are skipped (i.e., not compressed) before compression is attempted on another one of the plurality of data segments. When a data segment is compressed, the compression algorithm (and any associated parameter(s)) that is applied is selected based upon a variety of factors, such as the length of the data segment, CPU speed, CPU availability, and/or data throughput such as the network bandwidth or network availability (e.g., where data is to be transmitted via a network interface).

Abstract: Methods and apparatus for generating a secondary pool of data are disclosed. A primary pool of data is obtained or identified, where the primary pool of data includes a primary seed and one or more generations of data, wherein each of the generations of data in the primary pool of data includes one or more data blocks that have changed with reference to a safeset corresponding to a previous backup, the safeset corresponding to the previous backup including (e.g., referencing) the primary seed. A secondary pool of data is generated and at least a portion of the data in the primary pool of data is transferred to the secondary pool of data.

Abstract: A system and method for data backup over a network has been developed. The method includes creating a baseline copy of the data files that are to be archived. When the data is subsequently being backed up, the system checks for the presence of newly added files by comparing the sort order of the present data files with the sort order of the baseline copy. Any newly added files are then saved to the baseline copy. The system checks for any changes in existing files by comparing the hash numbers of the present data files with the hash numbers of the data files in the baseline copy. Any changed files are then merged into their corresponding data files in the baseline copy.