Cloud Architecture: Availability Vs Durability
Availability refers to system uptime. Availability is achieved through hardware redundancy. If any component fails, hardware redudundacy helps in system uptime .
Durability refers to long-term data protection, i.e. the stored data does not suffer from bit rot, degradation or other corruption. Rather than focusing on hardware redundancy, it is concerned with data redundancy so that data is never lost or compromised.