Patent attributes
An efficient data deduplication method for use in a dispersed storage network (DSN). After a data object is received for storage in the DSN, it is determined whether a substantially identical data object has previously been encrypted and stored. The determination may be made, for example, by comparing an encryption key reference value relating to the data object to key reference information stored in DSN memory. If not detected, the data object is encrypted using an encryption key based on the data object. The encrypted data object is then compressed and stored. The encryption key and a key reference value are also stored as encoded key slices in DSN memory. If the data object was previously stored, it is encrypted using a retrieved encryption key that is substantially identical to the data object. The data object may then be compressed for storage using a pattern based data compression function.
