EC-Council EDRP key terms

A structured study that identifies critical business processes and quantifies how much outage, data loss, or degradation each can tolerate, producing recovery priorities and time objectives that drive the DR strategy.

A documented set of procedures, roles, and resources for restoring technology services and data at an alternate site or rebuilt primary site after a disruptive event, with defined activation criteria and testing cadence.

The broader organizational plan that keeps essential business functions operating during and after disruption, covering people, facilities, suppliers, and communications in addition to IT recovery.

The target elapsed time within which a process, system, or service must be restored after disruption before the impact becomes unacceptable. RTO is a design constraint, not a promise of actual performance.

The maximum amount of data, measured in time, that an organization can afford to lose. RPO sets backup frequency, replication lag tolerance, and journal or log retention requirements.

The total time a business process can be unavailable before the organization suffers unacceptable harm. MTD is set by the business and is always greater than or equal to the RTO plus work recovery time.

The period after systems are technically restored during which staff must validate data, catch up on backlog, and confirm the process is genuinely productive again. It consumes part of the MTD budget.

The average time required to restore a failed component or service to working order. MTTR is a reliability measure used to validate whether recovery capabilities can actually meet stated RTOs.

The measured time actually taken to restore a service in tests or real incidents. Comparing RTA against RTO reveals whether the recovery capability is credible or merely aspirational.

The formal, authorized decision to invoke the DR plan, naming the incident, the affected services, and the recovery tier to activate. Clear declaration authority prevents delayed or unauthorized failover.

A pre-arranged facility or cloud environment used to host critical systems when the primary site is unavailable. Types include hot, warm, cold, and reciprocal arrangements, differing in readiness and cost.

A fully equipped alternate facility with replicated data, configured hardware, and network connectivity ready to take over within minutes to hours. It carries the highest ongoing cost of the site options.

An alternate facility with power, connectivity, and some hardware in place but without current data or fully configured systems. Recovery requires restoring backups and installing or reconfiguring software.

A standby facility providing only basic infrastructure such as space, power, and cooling. Everything else, including hardware and data, must be procured and installed, making recovery slow but inexpensive.

An arrangement in which two organizations agree to host each other's critical operations at their respective sites during a disaster. It is low cost but risky if both parties are affected by the same event.

A formal contract among organizations, often in the same sector or region, to share resources, staff, or facilities during disruptions. Terms must specify priority, cost, and liability to be usable in a crisis.

A copy of data or system state retained so it can be restored after loss, corruption, or ransomware. Effectiveness depends on scope, frequency, integrity verification, and protection from the same threat that destroyed the original.

A resilience guideline requiring at least three copies of data, on two different media types, with one copy stored offsite or offline. It reduces the chance that a single incident destroys every recoverable copy.

A backup written to storage that cannot be altered or deleted for a defined retention period, even by administrators or compromised credentials. It is a primary defense against ransomware encryption or deletion of backups.

A copy stored on a system physically or logically isolated from production networks, reachable only through controlled processes. Isolation prevents malware from spreading to the backup during a network compromise.

The scheduled period during which backups run, chosen to limit performance impact on production. Window length constrains how much data can be captured and therefore influences achievable RPO.

A complete copy of all selected data regardless of prior backups. It simplifies restoration but consumes the most storage and time, and is usually combined with incremental or differential backups.

A backup that captures only data changed since the most recent backup of any type. It is fast and space-efficient but restoration requires the last full backup plus every subsequent incremental in sequence.

A backup that captures all data changed since the last full backup. Restores need only the full plus the latest differential, trading more storage per backup for simpler and faster recovery.

A full backup image assembled from an existing full backup plus subsequent incremental backups, without re-reading production data. It reduces backup window load while providing a consolidated recovery point.

A point-in-time image of a volume or virtual machine, typically fast and space-efficient through copy-on-write. Snapshots are not substitutes for backups because they usually reside on the same storage system.

Continuous or scheduled copying of data or virtual machines from one location to another to maintain a usable secondary copy. Synchronous replication gives near-zero data loss; asynchronous replication tolerates latency at some RPO cost.

A condition in replicated or clustered systems where two nodes both believe they are primary and accept writes, producing divergent data. Recovery requires manual reconciliation and risks data loss.

The process of shifting service from a failed primary component or site to a standby one. Automated failover is faster but needs safeguards against false triggers; manual failover is slower but more controlled.

The planned return of services from the standby environment to the restored primary. Failback is often more complex than failover and requires synchronization, validation, and a scheduled low-risk window.

Design that minimizes service interruption through redundancy, clustering, and automatic failover, typically targeting minutes or seconds of downtime. HA addresses component failure, not full-site disasters.

The ability of a system to continue operating correctly despite failure of a component, often through duplicated hardware and no service interruption. It is more costly than high availability but yields near-zero downtime.

Deliberate duplication of components, paths, power, or data so that no single failure causes loss of service. Redundancy can be active-active, active-passive, or standby, each with different cost and recovery characteristics.

Any component whose failure would halt a critical service because no alternative path or duplicate exists. Identifying and eliminating SPOFs is a core outcome of continuity and recovery planning.

The minimum number of cluster nodes that must agree before the cluster continues operating, used to prevent split-brain. Loss of quorum typically forces the cluster offline to protect data integrity.

Planned exercises that validate whether recovery plans and technology actually work, ranging from plan walkthroughs and tabletop exercises to partial and full failover tests with measured recovery times.

A discussion-based session in which participants walk through a simulated disaster scenario, testing decision-making, roles, and communications without touching production systems. It surfaces plan gaps cheaply.

A verification that backed-up data can actually be recovered and is usable, including integrity checks and application-level validation. Untested backups are commonly discovered to be unusable during real incidents.

The designated group responsible for incident command during a disruption, including decision authority, communications, and coordination with recovery teams. Clear membership and alternates prevent leadership vacuums.

A contract defining expected service levels, such as availability and recovery commitments, plus remedies for shortfalls. DR objectives must be consistent with SLAs promised to customers and partners.

The balance between how quickly an alternate site can resume operations and how much it costs to keep ready. Hot sites cost most and recover fastest; cold sites cost least and recover slowest.

The process of restoring operations after ransomware without paying, relying on isolated immutable backups, clean rebuilds, credential rotation, and validation that the threat is fully evicted before reconnection.