Explanation
Why AWS Snowball is the correct answer:
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Data Volume and Time Constraints:
- 20 TB = 20,000 GB = 20,000,000 MB
- Network bandwidth: 15 Mbps = 1.875 MB/s (15 ÷ 8)
- Maximum utilization: 70% = 1.3125 MB/s
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Time Calculation:
- At maximum throughput: 20,000,000 MB ÷ 1.3125 MB/s = 15,238,095 seconds
- This equals approximately 176 days (15,238,095 ÷ 86,400 seconds/day)
- The requirement is 30 days, which is impossible with the given network constraints
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AWS Snowball Solution:
- AWS Snowball is a physical data transport solution that uses secure appliances to transfer large amounts of data
- You can order a Snowball device, load your data onto it, and ship it back to AWS
- This bypasses network limitations entirely
- Each Snowball device can handle up to 80 TB of data
- The transfer happens offline, so network bandwidth is not a constraint
Why other options are incorrect:
B. AWS DataSync:
- Designed for ongoing data synchronization over the network
- Still uses network bandwidth, so it would take ~176 days
- Not suitable for one-time migration with tight deadlines and bandwidth constraints
C. Secure VPN connection:
- Would use the same limited network bandwidth
- Would take ~176 days to complete
- Doesn't address the fundamental bandwidth limitation
D. Amazon S3 Transfer Acceleration:
- Uses Amazon CloudFront's globally distributed edge locations
- Optimizes for faster uploads but still uses network bandwidth
- Maximum improvement is limited by the source's upload capacity
- Would still take far longer than 30 days
Key Takeaway: When migrating large datasets with limited bandwidth and tight deadlines, AWS Snowball (or Snowmobile for petabyte-scale data) is the appropriate solution for offline data transfer.
