# Backup Strategies (Full/Incremental/Differential/Synthetic) One-sentence definition: Methods to copy data for recovery with trade-offs in time and storage. ## Key Facts - Full: easiest restore, heaviest backup; Incremental: fastest backup; Differential: middle. - Synthetic fulls merge incrementals to reduce window. - Keep 3-2-1: 3 copies, 2 media, 1 offsite/immutable. - Encrypt at rest/in transit; test restores regularly. - **Verify:** check official (ISC)² CBK and current exam outline. ## Exam Relevance - Match method to RTO/RPO and bandwidth/storage constraints. **Mnemonic:** “**Full** easy restore, **incr** easy backup.” ## Mini Scenario Q: Limited backup window, aggressive RPO—pick? A: Incrementals with periodic synthetic fulls. ## Revision Checklist - Define three types. - 3-2-1 rule. - Encryption/test rule. ## Related [[Restore Testing and Recovery Procedures]] · [[Disaster Recovery Strategies (RTO RPO Hot Warm Cold)]] · [[Identity Resilience and DR]] · [[Ransomware Readiness Assessment]] · [[Business Continuity Operations and Crisis Communications]] · [[Domain 7 - Index]]