What is the key difference between Amazon S3 Standard-Infrequent Access (S3 Standard-IA) and S3 One Zone-Infrequent Access (S3 One Zone-IA)?
Show answer and explanation
Answer: B
The meaningful distinction is redundancy: Standard-IA stores data across at least three Availability Zones, while One Zone-IA keeps it in exactly one. That single-AZ design makes One Zone-IA about 20% cheaper but exposes the data to total loss if that AZ is ever destroyed.
Both classes return data with millisecond access and the same retrieval performance, so speed is not the differentiator.
Why the other options are wrong
- A. It is the reverse — Standard-IA's multi-AZ storage makes it more expensive per gigabyte than One Zone-IA.
- C. Single-AZ storage mechanically cannot give higher durability or availability than data spread across three or more AZs.
- D. Both classes provide the same millisecond access; AZ redundancy is the difference, not retrieval speed.
Exam tip. One Zone-IA = cheaper but single AZ (AZ loss = data loss). Standard-IA = multi-AZ. Everything else about them is similar.