Non-authoritative restore is restore the domain CONTROLLER to its state at the time of backup, and allows normal replication to overwrite RESTORED domain controller with any CHANGES that have occurred after the backup.

After system state restore, domain controller QUERIES its replication partners and GET the changes after backup date, to ensure that the domain controller has an accurate and updated copy of the Active Directory database.

Non-authoritative restore is the default method for restoring Active Directory, just a restore of system state is non-authoritative restore and mostly we use this for Active Directory data loss or corruption.

Non-authoritative restore is restore the domain controller to its state at the time of backup, and allows normal replication to overwrite restored domain controller with any changes that have occurred after the backup.

After system state restore, domain controller queries its replication partners and get the changes after backup date, to ensure that the domain controller has an accurate and updated copy of the Active Directory database.

Non-authoritative restore is the default method for restoring Active Directory, just a restore of system state is non-authoritative restore and mostly we use this for Active Directory data loss or corruption.