Which statement best describes synchronous vs asynchronous replication with respect to RPO?

Which statement best describes synchronous vs asynchronous replication with respect to RPO?

• A. Synchronous replication yields zero RPO; asynchronous yields non-zero RPO.
• B. Synchronous replication yields near-zero RPO; asynchronous yields near-zero RPO.
• C. Synchronous replication yields near-zero RPO; asynchronous results in non-zero RPO with potential data loss in a failure.
• D. Synchronous replication yields non-zero RPO; asynchronous yields zero RPO.

Answer: (C)

The statement tests how replication mode affects the Recovery Point Objective (RPO). RPO measures how much data could be lost in a failure, expressed in time. With synchronous replication, a write is considered complete only after it has been durably written at both the primary site and the replica. That means data loss in a failure would be limited to the small window of time it takes to complete those synchronized writes—practically near-zero RPO, though in real systems it’s often described as near-zero due to network latency and other small delays. With asynchronous replication, the write is acknowledged at the primary before it is replicated to the remote site. If a failure occurs before the replication catches up, any data not yet copied to the replica could be lost. That makes the RPO non-zero and tied to the lag between the primary and the replica, with potential data loss corresponding to that lag. So the correct choice states that synchronous replication yields near-zero RPO, while asynchronous results in non-zero RPO with potential data loss in a failure. The other options misstate this relationship by implying zero RPO for asynchronous or by swapping which method yields higher RPO.

The statement tests how replication mode affects the Recovery Point Objective (RPO). RPO measures how much data could be lost in a failure, expressed in time. With synchronous replication, a write is considered complete only after it has been durably written at both the primary site and the replica. That means data loss in a failure would be limited to the small window of time it takes to complete those synchronized writes—practically near-zero RPO, though in real systems it’s often described as near-zero due to network latency and other small delays.

With asynchronous replication, the write is acknowledged at the primary before it is replicated to the remote site. If a failure occurs before the replication catches up, any data not yet copied to the replica could be lost. That makes the RPO non-zero and tied to the lag between the primary and the replica, with potential data loss corresponding to that lag.

So the correct choice states that synchronous replication yields near-zero RPO, while asynchronous results in non-zero RPO with potential data loss in a failure. The other options misstate this relationship by implying zero RPO for asynchronous or by swapping which method yields higher RPO.