Which term describes keeping multiple copies of data across locations to improve reliability?

• A. Redundancy
• B. High Availability
• C. Replication
• D. Duplication

Answer: (C)

Keeping multiple copies of data across locations is called replication. This practice ensures reliability by providing alternate sources of data if one site fails, supports disaster recovery, and can reduce latency by serving users from the nearest copy. Replication can be done in different ways, such as synchronous replication, where updates are written to all copies in real time, or asynchronous replication, where updates are propagated with a slight delay.

Redundancy is a broader idea of having extra components or copies to prevent failure, but replication specifically describes the ongoing process of creating and maintaining those copies across sites. Duplication is simply making another copy, without necessarily addressing synchronization or distribution. High Availability is the outcome of designs that minimize downtime, often using replication as a key mechanism, but it isn’t the term for the act of keeping multiple data copies.