Source deduplication is a data backup technique that eliminates multiple copies of repetitive information before transferring the data to the backup location or storage system.

The solution involves hashing blocks of data (fixed or variable) and, before sending the data block to storage, the backup solution queries the storage system to determine if the hash value of the block is already stored there; if so, only the hash value is sent.

By processing data directly on the server or the source system, this method significantly reduces the volume of data to be backed up, thereby optimizing the use of network bandwidth and storage space.