EdgeCampus has 200 cameras (2 Mb/s each) streaming to three edge servers; detection runs at the edge; the university wants (a) 7 days of raw video on campus for security investigations, (b) detection results (≈ 1 KB per detection, 50 detections/s in total) kept for 5 years, and (c) the ability to survive the loss of one edge server without losing results.
- Compute the daily raw-video volume, the 7-day storage needed, and the yearly volume of detection results.
- Design the storage: devices (HDD/SSD), RAID or replication/erasure coding at the edge, what goes to the cloud (object storage) and when. Justify with numbers (capacity, IOPS/throughput, bandwidth to the cloud).
- Describe how you guarantee that detection results are not lost (write path, fsync/replication, acknowledgement).
- Discuss privacy: what must never leave the campus, and how retention (deleting video after 7 days) is enforced.