The Rsync Algorithm (2016)

See also: "The rsync algorithm" (1998) https://rsync.samba.org/tech_report/

(and also https://rsync.samba.org/how-rsync-works.html)

The great innovation with rsync was the idea of having a rolling checksum. It allows:

  - quickly identifying which parts of a file have changed
  - efficient computation (because the checksums are incremental / rolling)