In addition, file attributes such as ownership and rights can be lost by client backups. At some point it becomes impossible to pass enough data over the network in the time allotted for a full nightly backup. It is far faster to pass data between two devices on a SCSI bus than over a network. Unattended backups and scheduling. A server-based backup scheme can easily schedule backup and restore jobs for weeks and months in advance.
Client machines can suffer from network disconnections and are far less reliable.
While a mass-storage device can be many things, the usual device is a tape drive of some sort. The difference between storing information on a tape and storing it on a disk, though, can lead to some very common misconceptions. A disk is a random access device, while a tape drive is a sequential access device. Tape drives cannot immediately position to a particular block of data on the tape. Files, directories, and data are laid down on the medium one block after another.