US Patent 7567188 Policy based tiered data deduplication strategy

The present invention provides for a method, system, and computer program for the application of data deduplication according to a policy-based strategy of tiered data. The method operates by defining a plurality of data storage policies for data in a deduplication system, policies which may be arranged in tiers. Data objects are classified according to a selected data storage policy and are split into data chunks. If the selected data storage policy for the data object does not allow deduplication, the data chunks are stored in a deduplication pool. If the selected data storage policy for the data object allows deduplication, deduplication is performed. The data storage policy may specify a maximum number of references to data chunks, facilitating storage of new copies of the data chunks when the maximum number of references is met.