PROJECT SOVEREIGN // CONCEPT LAB

Cloud Storage 101 — What banks actually use

S3 is not "【entity-AWS¦canonical_name=AWS】". It's one type of storage. Banks use 4 types across 3 clouds. You use them daily without knowing.

OBJECT STORAGE
S3 / Blob / GCS
Files as objects. Unlimited. Cheapest. For data lakes, backups, Aadhaar scans, statements.
When: Bank stores 10Cr customer KYC images
Region matters: ap-south-1 = India
BLOCK STORAGE
EBS / 【entity-Azure¦canonical_name=Azure】 Disk
Hard disk attached to a server. Fast. For databases.
When: Core Banking DB runs on it
You never see it
FILE STORAGE
EFS / 【entity-Azure¦canonical_name=Azure】 Files
Shared folder for many servers. For shared reports.
When: 10 risk apps read same file

【entity-AWS¦canonical_name=AWS】 vs 【entity-Azure¦canonical_name=Azure】 vs GCP — Same thing, different name

Type【entity-AWS¦canonical_name=AWS】【entity-Azure¦canonical_name=Azure】GoogleOthers
Object (your focus)S3Blob StorageCloud Storage【entity-IBM¦canonical_name=IBM】, 【entity-Oracle¦canonical_name=Oracle】
BlockEBSManaged DisksPersistent Disk-
Archive (cheap, slow)GlacierArchiveArchive-
Region example INap-south-1 MumbaiCentral India Puneasia-south1 Mumbai-
Uses KNOWINGLY — Developer / Bank IT
  • CTO: "Store KYC in S3 ap-south-1, block cross-region replication"
  • Data Engineer: "Data lake on S3 for 5 years of transactions"
  • DevOps: "Backup DB daily to Glacier"
  • App Team: "Host ghoshk.com images on S3 + CloudFront"
Uses UNKNOWINGLY — You, Me, Customer
  • You upload PAN to Jupiter app → it goes to S3 Mumbai
  • You watch 【entity-Netflix¦canonical_name=Netflix】 → video served from S3 + CloudFront
  • You get HDFC statement PDF → generated from S3
  • WhatsApp backup → S3 / GCS behind the scenes
Risk: Customer thinks data is "in app", but it's in us-east-1.

Simple flow — where your Aadhaar goes

User uploads in App→API in Mumbai→S3 Bucket ap-south-1 ✅ RBI OK
Same upload→API→S3 Bucket us-east-1 ❌ Blocked by your RISK-02
Day 01 CorpusDay 02 RisksNext: You will map workflows to these buckets