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Financial Audit

Cauchy Erasure Coding vs. 3x Replication Economics

Financial and operational TCO models demonstrating 54% to 58% cost reductions in petabyte-scale storage.

Last updated: Sep 20, 2026 Format: Markdown / GFM

Cauchy Erasure Coding vs. 3x Replication Economics

For enterprise storage architects and Chief Financial Officers, storage cost is dominated not by software licenses, but by the physical hardware footprint: drive acquisition, server chassis, rack space amortization, power, and datacenter cooling.


The True Cost of 1 Petabyte Usable

Assuming an enterprise blend of high-density SAS drives and NVMe cache amortized over 4 years at approximately $22 per raw TB per year (inclusive of power and cooling):

Metric 3x Full Replication Ahmodi Profile (4+2) Ahmodi Profile (8+3) Ahmodi Profile (16+4)
Storage Efficiency 33.3% 66.7% 72.7% 80.0%
Raw Capacity Required for 1 PB 3,000 TB 1,500 TB 1,375 TB 1,250 TB
Physical 24TB Drives Required 125 Drives 63 Drives 58 Drives 52 Drives
Simultaneous Failures Tolerated 2 Drives 2 Drives 3 Drives 4 Drives
Annual TCO per Usable PB $66,000 / yr $33,000 / yr $30,250 / yr $27,500 / yr
Net Savings vs. Replication Baseline (0%) 50.0% 54.2% 58.3%

10 Petabyte Fleet Multi-Year Financial Savings

For a 10 PB enterprise deployment (typical for banking archives, seismic surveys, or smart city telemetry):

3x Replication Cost:  $660,000 / year (2.475 Million SAR)
Ahmodi (8+3) Cost:    $302,500 / year (1.134 Million SAR)
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Net Annual Savings:   +$357,500 / year (+1.34 Million SAR / year)
4-Year Fleet Savings: +$1,430,000 (+5.36 Million SAR)

Important

Greater Durability at Lower Cost: Ahmodi Profile (8+3) survives 3 simultaneous drive or rack crashes compared to only 2 in 3x replication, meaning enterprises achieve higher durability and availability while spending less than half on hardware.