Glossary A–ZLetter B
Backup
A backup is a copy of data kept in a second place, from which the data can be restored after a loss.
Losses are caused by hardware faults, operating errors, malware or a provider that fails. A backup only helps if it is stored separately from the original.
In a screen network, the valuable data is not on the players but in the management software: media, playlists, schedules, templates, users and device settings. With a cloud solution the provider usually takes the backups; with an in-house server it is the operator’s job. A widely used rule of thumb is 3-2-1: three copies on two different storage media, one of them off site.
A backup that has never been restored is a promise without proof; a regular test shows whether it is complete and how long restoring takes. Databases must be backed up during operation in such a way that the copy is consistent; a simple file copy is not always enough. Backups often contain personal data and credentials, so they should be encrypted and given a retention period. With cloud services it is worth asking whether the operator can obtain a copy of its own.