How to Move 1,000 TB from Nanjing to Beijing: Network Math vs. Human Courier

Network Transfer Estimate

Typical bandwidth options in China (as reported by a telecom employee) are:

Residential broadband: up to 1 Gbps downstream, 300 Mbps upstream.

Enterprise data‑dedicated line: up to 100 Gbps, ≈ 350,000 CNY per month.

Enterprise internet line: up to 10 Gbps, ≈ 540,000 CNY per month.

Assuming the 100 Gbps data line, the usable data rate is: 100 Gbps ÷ 8 = 12.5 GB/s Data transferred in one hour:

12.5 GB/s × 3600 s = 45,000 GB ≈ 45 TB

To move 1,000 TB the theoretical time is: 1,000 TB ÷ 45 TB/h ≈ 22.2 hours Using the 10 Gbps internet line would require roughly 10 days, while residential broadband would take several months.

Physical Transfer (Human‑Courier) Method

The most time‑efficient and cost‑effective approach is to ship hard‑drive containers by high‑speed rail.

Each 16 TB hard drive costs about 63 CNY.

Number of drives needed: 1,000 TB ÷ 16 TB ≈ 62.5 → 63 drives.

Drive cost: 63 CNY × 63 ≈ 3,937 CNY.

Transport timeline:

High‑speed train travel (Nanjing → Beijing): ~5 hours.

Door‑to‑door handling (loading, unloading, local transport): ~2 hours.

Total elapsed time: ~7 hours, comparable to a short flight.

Logistics cost:

Round‑trip high‑speed rail ticket: 464 CNY each way → 928 CNY total.

Taxi / local transport: ≈ 200 CNY.

Overall cost: ≈ 1,100 CNY, far lower than the multi‑hundred‑thousand‑yuan monthly network fees.

Never underestimate the bandwidth of a train full of disks.