US Patent 9442806 Block-level deduplication

Various systems and methods can perform block-level deduplication. For example, one method involves sending a chunk of data to a deduplication server for storage in a deduplicated data store. The chunk of data includes multiple blocks. Subsequent to sending the chunk of data to the deduplication server, the method detects that at least one of the blocks has been modified. In response, the method sends associated information as well as the modified blocks, which include at least one but fewer than all of the blocks in the chunk, to the deduplication server. The associated information identifies a location of the included blocks within the chunk of data. The method can be performed by a computing device implementing a deduplication client.