Business continuity and disaster recovery planning professionals rely on well-known metrics that are used to drive planning of emergency operations procedures and continuity of operations procedures. These metrics are:
- Maximum Tolerable Downtime (MTD) – this is an arbitrary time value that represents the greatest period of time that an organization is able to tolerate the outage of a critical process or system without sustaining permanent damage to the organization’s ongoing viability. The units of measure are typically days, but can be smaller (hours, minutes) or larger (weeks, months).
- Recovery Point Objective (RPO) – this is a time value that represents the maximum potential data loss in a disaster situation. For example, if an organization backs up data for a key business process once per day, the RPO would be 24 hours. This should not be confused with recovery time objective.
- Recovery Time Objective (RTO) – this is a time value that represents the maximum period of time that a business process or system would be incapacitated in the event of a disaster. This is largely independent of recovery point objective, which is dependent on facilities that replicate key business data to another location, preserving it in case the primary location suffers a disaster that damages business data.
- Recovery Consistency Objective (RCO) – expressed as a percentage, this represents the maximum loss of data consistency during a disaster. In complex, distributed systems, it may not be possible to perfectly synchronize all business records. When a disaster occurs, often there is some inconsistency found on a recovery site where some data is “fresher” than other data. Different organizations and industries will have varying tolerances for data consistency in a disaster situation.
In my research on the topic of business continuity planning and disaster recovery planning, I have come across a standard metric that represents the capacity for a recovery system to process business transactions, as compared to the primary system. In professional dealings I have encountered this topic many times.
A new metric is proposed that is used to establish and communicate a recovery objective that represents the capacity of a recovery system:
- Recovery Capacity Objective (RCapO) – expressed as a percentage, this represents the capacity of a recovery process or system as compared to the primary process or system.
Arguments for this metric:
- Awareness. The question of recovery system capacity is not consistently addressed within an organization or to the users of a process or system.
- Consistency. The adoption of a standard metric on recovery system capacity will facilitate adoption of the metric.
- Planning. The users of a process or system can reasonably anticipate business conditions should a business process or system suffer a disaster that results in the implementation of emergency response procedures.