At the core of every effective data protection strategy lies a solid business continuity plan. All enterprises need an explicitly defined and routinely tested plan to minimize the potential impact to the workflow when a failure occurs or in the event of a natural disaster. There are several ways to address data protection and most enterprises adopt a combination of these methods, to varying degrees.
Among the primary approaches to data protection are fault tolerance, redundancy, snapshots, replication (local, geographically separate, or both), and backups to nearline storage, VTL, or tape.
Some of these methods are biased towards cost efficiency but have a higher risk associated with them, and others represent a higher cost but also offer an increased level of protection. Two ways to measure cost compared to risk from a data protection point of view are:
Recovery Time Objective (RTO): RTO is the allotted amount of time within a Service Level Agreement (SLA) to recover data. For example, an RTO of four hours means data must be restored and made available within four hours of an outage.
Recovery Point Objective (RPO): RPO is the acceptable amount of data loss that can be tolerated per an SLA. With an RPO of 30 minutes, this is the maximum amount of time that can elapse since the last backup or snapshot was taken.